/*
  pygame - Python Game Library
  Copyright (C) 2000-2001  Pete Shinners
  Copyright (C) 2006 Rene Dudfield
  Copyright (C) 2007 Marcus von Appen

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Library General Public
  License as published by the Free Software Foundation; either
  version 2 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Library General Public License for more details.

  You should have received a copy of the GNU Library General Public
  License along with this library; if not, write to the Free
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  Pete Shinners
  pete@shinners.org
*/

#define NO_PYGAME_C_API
#include "_surface.h"

/* The structure passed to the low level blit functions */
typedef struct
{
    int              width;
    int              height;
    Uint8           *s_pixels;
    int              s_pxskip;
    int              s_skip;
    Uint8           *d_pixels;
    int              d_pxskip;
    int              d_skip;
    SDL_PixelFormat *src;
    SDL_PixelFormat *dst;
    Uint32           src_flags;
    Uint32           dst_flags;
} SDL_BlitInfo;

static void alphablit_alpha (SDL_BlitInfo * info);
static void alphablit_colorkey (SDL_BlitInfo * info);
static void alphablit_solid (SDL_BlitInfo * info);
static void blit_blend_add (SDL_BlitInfo * info);
static void blit_blend_sub (SDL_BlitInfo * info);
static void blit_blend_mul (SDL_BlitInfo * info);
static void blit_blend_min (SDL_BlitInfo * info);
static void blit_blend_max (SDL_BlitInfo * info);

static void blit_blend_rgba_add (SDL_BlitInfo * info);
static void blit_blend_rgba_sub (SDL_BlitInfo * info);
static void blit_blend_rgba_mul (SDL_BlitInfo * info);
static void blit_blend_rgba_min (SDL_BlitInfo * info);
static void blit_blend_rgba_max (SDL_BlitInfo * info);

static void blit_blend_premultiplied (SDL_BlitInfo * info);


static int
SoftBlitPyGame (SDL_Surface * src, SDL_Rect * srcrect,
                SDL_Surface * dst, SDL_Rect * dstrect, int the_args);
extern int  SDL_RLESurface (SDL_Surface * surface);
extern void SDL_UnRLESurface (SDL_Surface * surface, int recode);

static int
SoftBlitPyGame (SDL_Surface * src, SDL_Rect * srcrect, SDL_Surface * dst,
                SDL_Rect * dstrect, int the_args)
{
    int okay;
    int src_locked;
    int dst_locked;

    /* Everything is okay at the beginning...  */
    okay = 1;

    /* Lock the destination if it's in hardware */
    dst_locked = 0;
    if (SDL_MUSTLOCK (dst))
    {
        if (SDL_LockSurface (dst) < 0)
            okay = 0;
        else
            dst_locked = 1;
    }
    /* Lock the source if it's in hardware */
    src_locked = 0;
    if (SDL_MUSTLOCK (src))
    {
        if (SDL_LockSurface (src) < 0)
            okay = 0;
        else
            src_locked = 1;
    }

    /* Set up source and destination buffer pointers, and BLIT! */
    if (okay && srcrect->w && srcrect->h)
    {
        SDL_BlitInfo    info;

        /* Set up the blit information */
        info.width = srcrect->w;
        info.height = srcrect->h;
        info.s_pixels = (Uint8 *) src->pixels + src->offset +
            (Uint16) srcrect->y * src->pitch +
            (Uint16) srcrect->x * src->format->BytesPerPixel;
        info.s_pxskip = src->format->BytesPerPixel;
        info.s_skip = src->pitch - info.width * src->format->BytesPerPixel;
        info.d_pixels = (Uint8 *) dst->pixels + dst->offset +
            (Uint16) dstrect->y * dst->pitch +
            (Uint16) dstrect->x * dst->format->BytesPerPixel;
        info.d_pxskip = dst->format->BytesPerPixel;
        info.d_skip = dst->pitch - info.width * dst->format->BytesPerPixel;
        info.src = src->format;
        info.dst = dst->format;
        info.src_flags = src->flags;
        info.dst_flags = dst->flags;

        if (info.d_pixels > info.s_pixels)
        {
            int span = info.width * info.src->BytesPerPixel;
            Uint8 *srcpixend =
                info.s_pixels + (info.height - 1) * src->pitch + span;

            if (info.d_pixels < srcpixend)
            {
                int dstoffset = (info.d_pixels - info.s_pixels) % src->pitch;

                if (dstoffset < span || dstoffset > src->pitch - span)
                {
                    /* Overlapping Self blit with positive destination offset.
                       Reverse direction of the blit.
                    */
                    info.s_pixels = srcpixend - info.s_pxskip;
                    info.s_pxskip = -info.s_pxskip;
                    info.s_skip = -info.s_skip;
                    info.d_pixels = (info.d_pixels +
                                     (info.height - 1) * dst->pitch +
                                     span - info.d_pxskip);
                    info.d_pxskip = -info.d_pxskip;
                    info.d_skip = -info.d_skip;
                }
            }
        }

        switch (the_args)
        {
        case 0:
        {
            if (src->flags & SDL_SRCALPHA && src->format->Amask)
                alphablit_alpha (&info);
            else if (src->flags & SDL_SRCCOLORKEY)
                alphablit_colorkey (&info);
            else
                alphablit_solid (&info);
            break;
        }
        case PYGAME_BLEND_ADD:
        {
            blit_blend_add (&info);
            break;
        }
        case PYGAME_BLEND_SUB:
        {
            blit_blend_sub (&info);
            break;
        }
        case PYGAME_BLEND_MULT:
        {
            blit_blend_mul (&info);
            break;
        }
        case PYGAME_BLEND_MIN:
        {
            blit_blend_min (&info);
            break;
        }
        case PYGAME_BLEND_MAX:
        {
            blit_blend_max (&info);
            break;
        }

        case PYGAME_BLEND_RGBA_ADD:
        {
        blit_blend_rgba_add (&info);
        break;
        }
        case PYGAME_BLEND_RGBA_SUB:
        {
            blit_blend_rgba_sub (&info);
            break;
        }
        case PYGAME_BLEND_RGBA_MULT:
        {
            blit_blend_rgba_mul (&info);
            break;
        }
        case PYGAME_BLEND_RGBA_MIN:
        {
            blit_blend_rgba_min (&info);
            break;
        }
        case PYGAME_BLEND_RGBA_MAX:
        {
            blit_blend_rgba_max (&info);
            break;
        }
        case PYGAME_BLEND_PREMULTIPLIED:
        {
            blit_blend_premultiplied (&info);
            break;
        }




        default:
        {
            SDL_SetError ("Invalid argument passed to blit.");
            okay = 0;
            break;
        }
        }
    }
    /* We need to unlock the surfaces if they're locked */
    if (dst_locked)
        SDL_UnlockSurface (dst);
    if (src_locked)
        SDL_UnlockSurface (src);
    /* Blit is done! */
    return (okay ? 0 : -1);
}








/* --------------------------------------------------------- */


static void
blit_blend_rgba_add (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    Uint32          tmp;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (!dstppa)
    {
        blit_blend_add (info);
        return;
    }

    if (srcbpp == 4 && dstbpp == 4 &&
        srcfmt->Rmask == dstfmt->Rmask &&
        srcfmt->Gmask == dstfmt->Gmask &&
        srcfmt->Bmask == dstfmt->Bmask &&
        srcfmt->Amask == dstfmt->Amask &&
        info->src_flags & SDL_SRCALPHA)
    {
        int incr = srcpxskip > 0 ? 1 : -1;
        if (incr < 0)
        {
            src += 3;
            dst += 3;
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                REPEAT_4(
                {
                    tmp = (*dst) + (*src);
                    (*dst) = (tmp <= 255 ? tmp : 255);
                    src += incr;
                    dst += incr;
                });
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_rgba_sub (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    Sint32          tmp2;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (!dstppa)
    {
        blit_blend_sub (info);
        return;
    }

    if (srcbpp == 4 && dstbpp == 4 &&
        srcfmt->Rmask == dstfmt->Rmask &&
        srcfmt->Gmask == dstfmt->Gmask &&
        srcfmt->Bmask == dstfmt->Bmask &&
        srcfmt->Amask == dstfmt->Amask &&
        info->src_flags & SDL_SRCALPHA)
    {
        int incr = srcpxskip > 0 ? 1 : -1;
        if (incr < 0)
        {
            src += 3;
            dst += 3;
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                REPEAT_4(
                {
                    tmp2 = (*dst) - (*src);
                    (*dst) = (tmp2 >= 0 ? tmp2 : 0);
                    src += incr;
                    dst += incr;
                });
                }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_rgba_mul (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    Uint32          tmp;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (!dstppa)
    {
        blit_blend_mul (info);
        return;
    }

    if (srcbpp == 4 && dstbpp == 4 &&
        srcfmt->Rmask == dstfmt->Rmask &&
        srcfmt->Gmask == dstfmt->Gmask &&
        srcfmt->Bmask == dstfmt->Bmask &&
        srcfmt->Amask == dstfmt->Amask &&
        info->src_flags & SDL_SRCALPHA)
    {
        int incr = srcpxskip > 0 ? 1 : -1;
        if (incr < 0)
        {
            src += 3;
            dst += 3;
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                REPEAT_4(
                {
                    tmp = ((*dst) && (*src)) ? ((*dst) * (*src)) >> 8 : 0;
                    (*dst) = (tmp <= 255 ? tmp : 255);
                    src += incr;
                    dst += incr;
                });
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_rgba_min (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (!dstppa)
    {
    blit_blend_min (info);
    return;
    }

    if (srcbpp == 4 && dstbpp == 4 &&
        srcfmt->Rmask == dstfmt->Rmask &&
        srcfmt->Gmask == dstfmt->Gmask &&
        srcfmt->Bmask == dstfmt->Bmask &&
        srcfmt->Amask == dstfmt->Amask &&
        info->src_flags & SDL_SRCALPHA)
    {
        int incr = srcpxskip > 0 ? 1 : -1;
        if (incr < 0)
        {
            src += 3;
            dst += 3;
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                REPEAT_4(
                {
                    if ((*src) < (*dst))
                    (*dst) = (*src);
                    src += incr;
                    dst += incr;
                });
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_rgba_max (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (!dstppa)
    {
        blit_blend_max (info);
        return;
    }

    if (srcbpp == 4 && dstbpp == 4 &&
        srcfmt->Rmask == dstfmt->Rmask &&
        srcfmt->Gmask == dstfmt->Gmask &&
        srcfmt->Bmask == dstfmt->Bmask &&
        srcfmt->Amask == dstfmt->Amask &&
        info->src_flags & SDL_SRCALPHA)
    {
        int incr = srcpxskip > 0 ? 1 : -1;
        if (incr < 0)
        {
            src += 3;
            dst += 3;
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                REPEAT_4(
                {
                    if ((*src) > (*dst))
                    (*dst) = (*src);
                    src += incr;
                    dst += incr;
                });
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_RGBA_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_RGBA_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_premultiplied (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);
    int tmp;

    /*
    printf ("Premultiplied alpha blit with %d and %d\n", srcbpp, dstbpp);
    */

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND_PREMULTIPLIED (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND_PREMULTIPLIED (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND_PREMULTIPLIED (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND_PREMULTIPLIED (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}













/* --------------------------------------------------------- */


static void
blit_blend_add (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    Uint32          tmp;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (srcbpp >= 3 && dstbpp >= 3 && !(info->src_flags & SDL_SRCALPHA))
    {
        size_t srcoffsetR, srcoffsetG, srcoffsetB;
        size_t dstoffsetR, dstoffsetG, dstoffsetB;
        if (srcbpp == 3)
        {
            SET_OFFSETS_24 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        else
        {
            SET_OFFSETS_32 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        if (dstbpp == 3)
        {
            SET_OFFSETS_24 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        else
        {
            SET_OFFSETS_32 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                tmp = dst[dstoffsetR] + src[srcoffsetR];
                dst[dstoffsetR] = (tmp <= 255 ? tmp : 255);
                tmp = dst[dstoffsetG] + src[srcoffsetG];
                dst[dstoffsetG] = (tmp <= 255 ? tmp : 255);
                tmp = dst[dstoffsetB] + src[srcoffsetB];
                dst[dstoffsetB] = (tmp <= 255 ? tmp : 255);
                src += srcpxskip;
                dst += dstpxskip;
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_ADD (tmp, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_sub (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    Sint32          tmp2;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (srcbpp >= 3 && dstbpp >= 3 && !(info->src_flags & SDL_SRCALPHA))
    {
        size_t srcoffsetR, srcoffsetG, srcoffsetB;
        size_t dstoffsetR, dstoffsetG, dstoffsetB;
        if (srcbpp == 3)
        {
            SET_OFFSETS_24 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        else
        {
            SET_OFFSETS_32 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        if (dstbpp == 3)
        {
            SET_OFFSETS_24 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        else
        {
            SET_OFFSETS_32 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                tmp2 = dst[dstoffsetR] - src[srcoffsetR];
                dst[dstoffsetR] = (tmp2 >= 0 ? tmp2 : 0);
                tmp2 = dst[dstoffsetG] - src[srcoffsetG];
                dst[dstoffsetG] = (tmp2 >= 0 ? tmp2 : 0);
                tmp2 = dst[dstoffsetB] - src[srcoffsetB];
                dst[dstoffsetB] = (tmp2 >= 0 ? tmp2 : 0);
                src += srcpxskip;
                dst += dstpxskip;
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstfmt);
                    BLEND_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_SUB (tmp2, sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_mul (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    Uint32          tmp;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (srcbpp >= 3 && dstbpp >= 3 && !(info->src_flags & SDL_SRCALPHA))
    {
        size_t srcoffsetR, srcoffsetG, srcoffsetB;
        size_t dstoffsetR, dstoffsetG, dstoffsetB;
        if (srcbpp == 3)
        {
            SET_OFFSETS_24 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        else
        {
            SET_OFFSETS_32 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        if (dstbpp == 3)
        {
            SET_OFFSETS_24 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        else
        {
            SET_OFFSETS_32 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                tmp = ((dst[dstoffsetR] && src[srcoffsetR]) ?
                       (dst[dstoffsetR] * src[srcoffsetR]) >> 8 : 0);
                dst[dstoffsetR] = (tmp <= 255 ? tmp : 255);
                tmp = ((dst[dstoffsetG] && src[srcoffsetG]) ?
                       (dst[dstoffsetG] * src[srcoffsetG]) >> 8 : 0);
                dst[dstoffsetG] = (tmp <= 255 ? tmp : 255);
                tmp = ((dst[dstoffsetB] && src[srcoffsetB]) ?
                       (dst[dstoffsetB] * src[srcoffsetB]) >> 8 : 0);
                dst[dstoffsetB] = (tmp <= 255 ? tmp : 255);
                src += srcpxskip;
                dst += dstpxskip;
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MULT (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_min (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (srcbpp >= 3 && dstbpp >= 3 && !(info->src_flags & SDL_SRCALPHA))
    {
        size_t srcoffsetR, srcoffsetG, srcoffsetB;
        size_t dstoffsetR, dstoffsetG, dstoffsetB;
        if (srcbpp == 3)
        {
            SET_OFFSETS_24 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        else
        {
            SET_OFFSETS_32 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        if (dstbpp == 3)
        {
            SET_OFFSETS_24 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        else
        {
            SET_OFFSETS_32 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                if (src[srcoffsetR] < dst[dstoffsetR])
                {
                    dst[dstoffsetR] = src[srcoffsetR];
                }
                if (src[srcoffsetG] < dst[dstoffsetG])
                {
                    dst[dstoffsetG] = src[srcoffsetG];
                }
                if (src[srcoffsetB] < dst[dstoffsetB])
                {
                    dst[dstoffsetB] = src[srcoffsetB];
                }
                src += srcpxskip;
                dst += dstpxskip;
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MIN (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
blit_blend_max (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    Uint8           dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    if (srcbpp >= 3 && dstbpp >= 3 && !(info->src_flags & SDL_SRCALPHA))
    {
        size_t srcoffsetR, srcoffsetG, srcoffsetB;
        size_t dstoffsetR, dstoffsetG, dstoffsetB;
        if (srcbpp == 3)
        {
            SET_OFFSETS_24 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        else
        {
            SET_OFFSETS_32 (srcoffsetR, srcoffsetG, srcoffsetB, srcfmt);
        }
        if (dstbpp == 3)
        {
            SET_OFFSETS_24 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        else
        {
            SET_OFFSETS_32 (dstoffsetR, dstoffsetG, dstoffsetB, dstfmt);
        }
        while (height--)
        {
            LOOP_UNROLLED4(
            {
                if (src[srcoffsetR] > dst[dstoffsetR])
                {
                    dst[dstoffsetR] = src[srcoffsetR];
                }
                if (src[srcoffsetG] > dst[dstoffsetG])
                {
                    dst[dstoffsetG] = src[srcoffsetG];
                }
                if (src[srcoffsetB] > dst[dstoffsetB])
                {
                    dst[dstoffsetB] = src[srcoffsetB];
                }
                src += srcpxskip;
                dst += dstpxskip;
            }, n, width);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    BLEND_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else if (dstbpp == 3)
        {
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    BLEND_MAX (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}





/* --------------------------------------------------------- */




























static void
alphablit_alpha (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    int             dR, dG, dB, dA, sR, sG, sB, sA;
    Uint32          pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    /*
       printf ("Alpha blit with %d and %d\n", srcbpp, dstbpp);
       */

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
alphablit_colorkey (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    int             dR, dG, dB, dA, sR, sG, sB, sA;
    int             alpha = srcfmt->alpha;
    Uint32          colorkey = srcfmt->colorkey;
    Uint32          pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    /*
       printf ("Colorkey blit with %d and %d\n", srcbpp, dstbpp);
       */

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    sA = (*src == colorkey) ? 0 : alpha;
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    sA = (*src == colorkey) ? 0 : alpha;
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    sA = (pixel == colorkey) ? 0 : alpha;
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else if (dstbpp == 3)
        {
            /* This is interim code until SDL can properly handle self
               blits of surfaces with blanket alpha.
               */
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    sA = (pixel == colorkey) ? 0 : alpha;
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    sA = (pixel == colorkey) ? 0 : alpha;
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, sA, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

static void
alphablit_solid (SDL_BlitInfo * info)
{
    int             n;
    int             width = info->width;
    int             height = info->height;
    Uint8          *src = info->s_pixels;
    int             srcpxskip = info->s_pxskip;
    int             srcskip = info->s_skip;
    Uint8          *dst = info->d_pixels;
    int             dstpxskip = info->d_pxskip;
    int             dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    int             srcbpp = srcfmt->BytesPerPixel;
    int             dstbpp = dstfmt->BytesPerPixel;
    int             dR, dG, dB, dA, sR, sG, sB, sA;
    int             alpha = srcfmt->alpha;
    int             pixel;
    int             srcppa = (info->src_flags & SDL_SRCALPHA && srcfmt->Amask);
    int             dstppa = (info->dst_flags & SDL_SRCALPHA && dstfmt->Amask);

    /*
       printf ("Solid blit with %d and %d\n", srcbpp, dstbpp);
       */

    if (srcbpp == 1)
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND (sR, sG, sB, alpha, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* dstbpp > 1 */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXELVALS_1(sR, sG, sB, sA, src, srcfmt);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, alpha, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
    else /* srcbpp > 1 */
    {
        if (dstbpp == 1)
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXELVALS_1(dR, dG, dB, dA, dst, dstfmt);
                    ALPHA_BLEND (sR, sG, sB, alpha, dR, dG, dB, dA);
                    *dst = (Uint8) SDL_MapRGB (dstfmt, dR, dG, dB);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }

        }
        else if (dstbpp == 3)
        {
            /* This is interim code until SDL can properly handle self
               blits of surfaces with blanket alpha.
               */
            size_t offsetR, offsetG, offsetB;
            SET_OFFSETS_24 (offsetR, offsetG, offsetB, dstfmt);
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, alpha, dR, dG, dB, dA);
                    dst[offsetR] = dR;
                    dst[offsetG] = dG;
                    dst[offsetB] = dB;
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n, width);
                src += srcskip;
                dst += dstskip;
            }
        }
        else /* even dstbpp */
        {
            while (height--)
            {
                LOOP_UNROLLED4(
                {
                    GET_PIXEL(pixel, srcbpp, src);
                    GET_PIXELVALS (sR, sG, sB, sA, pixel, srcfmt, srcppa);
                    GET_PIXEL (pixel, dstbpp, dst);
                    GET_PIXELVALS (dR, dG, dB, dA, pixel, dstfmt, dstppa);
                    ALPHA_BLEND (sR, sG, sB, alpha, dR, dG, dB, dA);
                    CREATE_PIXEL(dst, dR, dG, dB, dA, dstbpp, dstfmt);
                    src += srcpxskip;
                    dst += dstpxskip;
                }, n ,width);
                src += srcskip;
                dst += dstskip;
            }
        }
    }
}

/*we assume the "dst" has pixel alpha*/
int
pygame_Blit (SDL_Surface * src, SDL_Rect * srcrect,
             SDL_Surface * dst, SDL_Rect * dstrect, int the_args)
{
    SDL_Rect        fulldst;
    int             srcx, srcy, w, h;

    /* Make sure the surfaces aren't locked */
    if (!src || !dst)
    {
        SDL_SetError ("SDL_UpperBlit: passed a NULL surface");
        return (-1);
    }
    if (src->locked || dst->locked)
    {
        SDL_SetError ("Surfaces must not be locked during blit");
        return (-1);
    }

    /* If the destination rectangle is NULL, use the entire dest surface */
    if (dstrect == NULL)
    {
        fulldst.x = fulldst.y = 0;
        dstrect = &fulldst;
    }

    /* clip the source rectangle to the source surface */
    if (srcrect)
    {
        int             maxw, maxh;

        srcx = srcrect->x;
        w = srcrect->w;
        if (srcx < 0)
        {
            w += srcx;
            dstrect->x -= srcx;
            srcx = 0;
        }
        maxw = src->w - srcx;
        if (maxw < w)
            w = maxw;

        srcy = srcrect->y;
        h = srcrect->h;
        if (srcy < 0)
        {
            h += srcy;
            dstrect->y -= srcy;
            srcy = 0;
        }
        maxh = src->h - srcy;
        if (maxh < h)
            h = maxh;

    }
    else
    {
        srcx = srcy = 0;
        w = src->w;
        h = src->h;
    }

    /* clip the destination rectangle against the clip rectangle */
    {
        SDL_Rect       *clip = &dst->clip_rect;
        int             dx, dy;

        dx = clip->x - dstrect->x;
        if (dx > 0)
        {
            w -= dx;
            dstrect->x += dx;
            srcx += dx;
        }
        dx = dstrect->x + w - clip->x - clip->w;
        if (dx > 0)
            w -= dx;

        dy = clip->y - dstrect->y;
        if (dy > 0)
        {
            h -= dy;
            dstrect->y += dy;
            srcy += dy;
        }
        dy = dstrect->y + h - clip->y - clip->h;
        if (dy > 0)
            h -= dy;
    }

    if (w > 0 && h > 0)
    {
        SDL_Rect        sr;

        sr.x = srcx;
        sr.y = srcy;
        sr.w = dstrect->w = w;
        sr.h = dstrect->h = h;
        return SoftBlitPyGame (src, &sr, dst, dstrect, the_args);
    }
    dstrect->w = dstrect->h = 0;
    return 0;
}

int
pygame_AlphaBlit (SDL_Surface * src, SDL_Rect * srcrect,
                  SDL_Surface * dst, SDL_Rect * dstrect, int the_args)
{
    return pygame_Blit (src, srcrect, dst, dstrect, the_args);
}
