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view src/video/SDL_blit_0.c @ 2247:93994f65c74c

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Removed hermes since it's LGPL and not compatible with a commercial license. Prepping for using MMX and SSE intrinsics instead of inline assembly. .. except for memcpy equivalents which only get faster if they can exploit the parallelism of loading into multiple SIMD registers. :)
author Sam Lantinga <slouken@libsdl.org>
date Wed, 15 Aug 2007 08:21:10 +0000
parents c121d94672cb
children 340942cfda48
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

#include "SDL_video.h"
#include "SDL_blit.h"

/* Functions to blit from bitmaps to other surfaces */

static void
BlitBto1(SDL_BlitInfo * info)
{
    int c;
    int width, height;
    Uint8 *src, *map, *dst;
    int srcskip, dstskip;

    /* Set up some basic variables */
    width = info->d_width;
    height = info->d_height;
    src = info->s_pixels;
    srcskip = info->s_skip;
    dst = info->d_pixels;
    dstskip = info->d_skip;
    map = info->table;
    srcskip += width - (width + 7) / 8;

    if (map) {
        while (height--) {
            Uint8 byte = 0, bit;
            for (c = 0; c < width; ++c) {
                if ((c & 7) == 0) {
                    byte = *src++;
                }
                bit = (byte & 0x80) >> 7;
                if (1) {
                    *dst = map[bit];
                }
                dst++;
                byte <<= 1;
            }
            src += srcskip;
            dst += dstskip;
        }
    } else {
        while (height--) {
            Uint8 byte = 0, bit;
            for (c = 0; c < width; ++c) {
                if ((c & 7) == 0) {
                    byte = *src++;
                }
                bit = (byte & 0x80) >> 7;
                if (1) {
                    *dst = bit;
                }
                dst++;
                byte <<= 1;
            }
            src += srcskip;
            dst += dstskip;
        }
    }
}
static void
BlitBto2(SDL_BlitInfo * info)
{
    int c;
    int width, height;
    Uint8 *src;
    Uint16 *map, *dst;
    int srcskip, dstskip;

    /* Set up some basic variables */
    width = info->d_width;
    height = info->d_height;
    src = info->s_pixels;
    srcskip = info->s_skip;
    dst = (Uint16 *) info->d_pixels;
    dstskip = info->d_skip / 2;
    map = (Uint16 *) info->table;
    srcskip += width - (width + 7) / 8;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (1) {
                *dst = map[bit];
            }
            byte <<= 1;
            dst++;
        }
        src += srcskip;
        dst += dstskip;
    }
}
static void
BlitBto3(SDL_BlitInfo * info)
{
    int c, o;
    int width, height;
    Uint8 *src, *map, *dst;
    int srcskip, dstskip;

    /* Set up some basic variables */
    width = info->d_width;
    height = info->d_height;
    src = info->s_pixels;
    srcskip = info->s_skip;
    dst = info->d_pixels;
    dstskip = info->d_skip;
    map = info->table;
    srcskip += width - (width + 7) / 8;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (1) {
                o = bit * 4;
                dst[0] = map[o++];
                dst[1] = map[o++];
                dst[2] = map[o++];
            }
            byte <<= 1;
            dst += 3;
        }
        src += srcskip;
        dst += dstskip;
    }
}
static void
BlitBto4(SDL_BlitInfo * info)
{
    int width, height;
    Uint8 *src;
    Uint32 *map, *dst;
    int srcskip, dstskip;
    int c;

    /* Set up some basic variables */
    width = info->d_width;
    height = info->d_height;
    src = info->s_pixels;
    srcskip = info->s_skip;
    dst = (Uint32 *) info->d_pixels;
    dstskip = info->d_skip / 4;
    map = (Uint32 *) info->table;
    srcskip += width - (width + 7) / 8;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (1) {
                *dst = map[bit];
            }
            byte <<= 1;
            dst++;
        }
        src += srcskip;
        dst += dstskip;
    }
}

static void
BlitBto1Key(SDL_BlitInfo * info)
{
    int width = info->d_width;
    int height = info->d_height;
    Uint8 *src = info->s_pixels;
    Uint8 *dst = info->d_pixels;
    int srcskip = info->s_skip;
    int dstskip = info->d_skip;
    Uint32 ckey = info->src->colorkey;
    Uint8 *palmap = info->table;
    int c;

    /* Set up some basic variables */
    srcskip += width - (width + 7) / 8;

    if (palmap) {
        while (height--) {
            Uint8 byte = 0, bit;
            for (c = 0; c < width; ++c) {
                if ((c & 7) == 0) {
                    byte = *src++;
                }
                bit = (byte & 0x80) >> 7;
                if (bit != ckey) {
                    *dst = palmap[bit];
                }
                dst++;
                byte <<= 1;
            }
            src += srcskip;
            dst += dstskip;
        }
    } else {
        while (height--) {
            Uint8 byte = 0, bit;
            for (c = 0; c < width; ++c) {
                if ((c & 7) == 0) {
                    byte = *src++;
                }
                bit = (byte & 0x80) >> 7;
                if (bit != ckey) {
                    *dst = bit;
                }
                dst++;
                byte <<= 1;
            }
            src += srcskip;
            dst += dstskip;
        }
    }
}

static void
BlitBto2Key(SDL_BlitInfo * info)
{
    int width = info->d_width;
    int height = info->d_height;
    Uint8 *src = info->s_pixels;
    Uint16 *dstp = (Uint16 *) info->d_pixels;
    int srcskip = info->s_skip;
    int dstskip = info->d_skip;
    Uint32 ckey = info->src->colorkey;
    Uint8 *palmap = info->table;
    int c;

    /* Set up some basic variables */
    srcskip += width - (width + 7) / 8;
    dstskip /= 2;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (bit != ckey) {
                *dstp = ((Uint16 *) palmap)[bit];
            }
            byte <<= 1;
            dstp++;
        }
        src += srcskip;
        dstp += dstskip;
    }
}

static void
BlitBto3Key(SDL_BlitInfo * info)
{
    int width = info->d_width;
    int height = info->d_height;
    Uint8 *src = info->s_pixels;
    Uint8 *dst = info->d_pixels;
    int srcskip = info->s_skip;
    int dstskip = info->d_skip;
    Uint32 ckey = info->src->colorkey;
    Uint8 *palmap = info->table;
    int c;

    /* Set up some basic variables */
    srcskip += width - (width + 7) / 8;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (bit != ckey) {
                SDL_memcpy(dst, &palmap[bit * 4], 3);
            }
            byte <<= 1;
            dst += 3;
        }
        src += srcskip;
        dst += dstskip;
    }
}

static void
BlitBto4Key(SDL_BlitInfo * info)
{
    int width = info->d_width;
    int height = info->d_height;
    Uint8 *src = info->s_pixels;
    Uint32 *dstp = (Uint32 *) info->d_pixels;
    int srcskip = info->s_skip;
    int dstskip = info->d_skip;
    Uint32 ckey = info->src->colorkey;
    Uint8 *palmap = info->table;
    int c;

    /* Set up some basic variables */
    srcskip += width - (width + 7) / 8;
    dstskip /= 4;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (bit != ckey) {
                *dstp = ((Uint32 *) palmap)[bit];
            }
            byte <<= 1;
            dstp++;
        }
        src += srcskip;
        dstp += dstskip;
    }
}

static void
BlitBtoNAlpha(SDL_BlitInfo * info)
{
    int width = info->d_width;
    int height = info->d_height;
    Uint8 *src = info->s_pixels;
    Uint8 *dst = info->d_pixels;
    int srcskip = info->s_skip;
    int dstskip = info->d_skip;
    const SDL_Color *srcpal = info->src->palette->colors;
    SDL_PixelFormat *dstfmt = info->dst;
    int dstbpp;
    int c;
    const int A = info->src->alpha;

    /* Set up some basic variables */
    dstbpp = dstfmt->BytesPerPixel;
    srcskip += width - (width + 7) / 8;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (1) {
                Uint32 pixel;
                unsigned sR, sG, sB;
                unsigned dR, dG, dB;
                sR = srcpal[bit].r;
                sG = srcpal[bit].g;
                sB = srcpal[bit].b;
                DISEMBLE_RGB(dst, dstbpp, dstfmt, pixel, dR, dG, dB);
                ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
                ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
            }
            byte <<= 1;
            dst += dstbpp;
        }
        src += srcskip;
        dst += dstskip;
    }
}

static void
BlitBtoNAlphaKey(SDL_BlitInfo * info)
{
    int width = info->d_width;
    int height = info->d_height;
    Uint8 *src = info->s_pixels;
    Uint8 *dst = info->d_pixels;
    int srcskip = info->s_skip;
    int dstskip = info->d_skip;
    SDL_PixelFormat *srcfmt = info->src;
    SDL_PixelFormat *dstfmt = info->dst;
    const SDL_Color *srcpal = srcfmt->palette->colors;
    int dstbpp;
    int c;
    const int A = srcfmt->alpha;
    Uint32 ckey = srcfmt->colorkey;

    /* Set up some basic variables */
    dstbpp = dstfmt->BytesPerPixel;
    srcskip += width - (width + 7) / 8;

    while (height--) {
        Uint8 byte = 0, bit;
        for (c = 0; c < width; ++c) {
            if ((c & 7) == 0) {
                byte = *src++;
            }
            bit = (byte & 0x80) >> 7;
            if (bit != ckey) {
                int sR, sG, sB;
                int dR, dG, dB;
                Uint32 pixel;
                sR = srcpal[bit].r;
                sG = srcpal[bit].g;
                sB = srcpal[bit].b;
                DISEMBLE_RGB(dst, dstbpp, dstfmt, pixel, dR, dG, dB);
                ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
                ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
            }
            byte <<= 1;
            dst += dstbpp;
        }
        src += srcskip;
        dst += dstskip;
    }
}

static SDL_loblit bitmap_blit[] = {
    NULL, BlitBto1, BlitBto2, BlitBto3, BlitBto4
};

static SDL_loblit colorkey_blit[] = {
    NULL, BlitBto1Key, BlitBto2Key, BlitBto3Key, BlitBto4Key
};

SDL_loblit
SDL_CalculateBlit0(SDL_Surface * surface, int blit_index)
{
    int which;

    if (surface->format->BitsPerPixel != 1) {
        /* We don't support sub 8-bit packed pixel modes */
        return NULL;
    }
    if (surface->map->dst->format->BitsPerPixel < 8) {
        which = 0;
    } else {
        which = surface->map->dst->format->BytesPerPixel;
    }
    switch (blit_index) {
    case 0:                    /* copy */
        return bitmap_blit[which];

    case 1:                    /* colorkey */
        return colorkey_blit[which];

    case 2:                    /* alpha */
        return which >= 2 ? BlitBtoNAlpha : NULL;

    case 4:                    /* alpha + colorkey */
        return which >= 2 ? BlitBtoNAlphaKey : NULL;
    }
    return NULL;
}

/* vi: set ts=4 sw=4 expandtab: */