view src/video/SDL_blit_copy.c @ 3468:789b97008d8a

My first OpenGL shader! Momma will be so proud! This shader implements the software renderer mask semantics where the source pixel is multiplied by the color and alpha modulation values and then any pixel with non-zero alpha is fully opaque. The OpenGL renderer on Mac OS X now passes all the automated render tests! :)
author Sam Lantinga <slouken@libsdl.org>
date Sat, 21 Nov 2009 05:29:31 +0000
parents 99210400e8b9
children 72024425b437
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 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"
#include "SDL_blit_copy.h"


#ifdef __SSE__
/* This assumes 16-byte aligned src and dst */
static __inline__ void
SDL_memcpySSE(Uint8 * dst, const Uint8 * src, int len)
{
    int i;

    __m128 values[4];
    for (i = len / 64; i--;) {
        _mm_prefetch(src, _MM_HINT_NTA);
        values[0] = *(__m128 *) (src + 0);
        values[1] = *(__m128 *) (src + 16);
        values[2] = *(__m128 *) (src + 32);
        values[3] = *(__m128 *) (src + 48);
        _mm_stream_ps((float *) (dst + 0), values[0]);
        _mm_stream_ps((float *) (dst + 16), values[1]);
        _mm_stream_ps((float *) (dst + 32), values[2]);
        _mm_stream_ps((float *) (dst + 48), values[3]);
        src += 64;
        dst += 64;
    }

    if (len & 63)
        SDL_memcpy(dst, src, len & 63);
}
#endif /* __SSE__ */

#ifdef __MMX__
#ifdef _MSC_VER
#pragma warning(disable:4799)
#endif
/* This assumes 8-byte aligned src and dst */
static __inline__ void
SDL_memcpyMMX(Uint8 * dst, const Uint8 * src, int len)
{
    int i;

    __m64 values[8];
    for (i = len / 64; i--;) {
        _mm_prefetch(src, _MM_HINT_NTA);
        values[0] = *(__m64 *) (src + 0);
        values[1] = *(__m64 *) (src + 8);
        values[2] = *(__m64 *) (src + 16);
        values[3] = *(__m64 *) (src + 24);
        values[4] = *(__m64 *) (src + 32);
        values[5] = *(__m64 *) (src + 40);
        values[6] = *(__m64 *) (src + 48);
        values[7] = *(__m64 *) (src + 56);
        _mm_stream_pi((__m64 *) (dst + 0), values[0]);
        _mm_stream_pi((__m64 *) (dst + 8), values[1]);
        _mm_stream_pi((__m64 *) (dst + 16), values[2]);
        _mm_stream_pi((__m64 *) (dst + 24), values[3]);
        _mm_stream_pi((__m64 *) (dst + 32), values[4]);
        _mm_stream_pi((__m64 *) (dst + 40), values[5]);
        _mm_stream_pi((__m64 *) (dst + 48), values[6]);
        _mm_stream_pi((__m64 *) (dst + 56), values[7]);
        src += 64;
        dst += 64;
    }

    if (len & 63)
        SDL_memcpy(dst, src, len & 63);
}
#endif /* __MMX__ */

void
SDL_BlitCopy(SDL_BlitInfo * info)
{
    Uint8 *src, *dst;
    int w, h;
    int srcskip, dstskip;

    w = info->dst_w * info->dst_fmt->BytesPerPixel;
    h = info->dst_h;
    src = info->src;
    dst = info->dst;
    srcskip = info->src_pitch;
    dstskip = info->dst_pitch;

#ifdef __SSE__
    if (SDL_HasSSE() &&
        !((uintptr_t) src & 15) && !(srcskip & 15) &&
        !((uintptr_t) dst & 15) && !(dstskip & 15)) {
        while (h--) {
            SDL_memcpySSE(dst, src, w);
            src += srcskip;
            dst += dstskip;
        }
        return;
    }
#endif

#ifdef __MMX__
    if (SDL_HasMMX() &&
        !((uintptr_t) src & 7) && !(srcskip & 7) &&
        !((uintptr_t) dst & 7) && !(dstskip & 7)) {
        while (h--) {
            SDL_memcpyMMX(dst, src, w);
            src += srcskip;
            dst += dstskip;
        }
        _mm_empty();
        return;
    }
#endif

    while (h--) {
        SDL_memcpy(dst, src, w);
        src += srcskip;
        dst += dstskip;
    }
}

void
SDL_BlitCopyOverlap(SDL_BlitInfo * info)
{
    Uint8 *src, *dst;
    int w, h;
    int skip;

    w = info->dst_w * info->dst_fmt->BytesPerPixel;
    h = info->dst_h;
    src = info->src;
    dst = info->dst;
    skip = info->src_pitch;
    if ((dst < src) || (dst >= (src + h * skip))) {
        SDL_BlitCopy(info);
    } else {
        src += ((h - 1) * skip);
        dst += ((h - 1) * skip);
        while (h--) {
            SDL_revcpy(dst, src, w);
            src -= skip;
            dst -= skip;
        }
    }
}

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