|  | /* | 
|  | Simple DirectMedia Layer | 
|  | Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org> | 
|  |  | 
|  | This software is provided 'as-is', without any express or implied | 
|  | warranty.  In no event will the authors be held liable for any damages | 
|  | arising from the use of this software. | 
|  |  | 
|  | Permission is granted to anyone to use this software for any purpose, | 
|  | including commercial applications, and to alter it and redistribute it | 
|  | freely, subject to the following restrictions: | 
|  |  | 
|  | 1. The origin of this software must not be misrepresented; you must not | 
|  | claim that you wrote the original software. If you use this software | 
|  | in a product, an acknowledgment in the product documentation would be | 
|  | appreciated but is not required. | 
|  | 2. Altered source versions must be plainly marked as such, and must not be | 
|  | misrepresented as being the original software. | 
|  | 3. This notice may not be removed or altered from any source distribution. | 
|  | */ | 
|  | #include "../SDL_internal.h" | 
|  |  | 
|  | #ifndef SDL_blit_h_ | 
|  | #define SDL_blit_h_ | 
|  |  | 
|  | #include "SDL_cpuinfo.h" | 
|  | #include "SDL_endian.h" | 
|  | #include "SDL_surface.h" | 
|  |  | 
|  | /* Table to do pixel byte expansion */ | 
|  | extern Uint8* SDL_expand_byte[9]; | 
|  |  | 
|  | /* SDL blit copy flags */ | 
|  | #define SDL_COPY_MODULATE_COLOR     0x00000001 | 
|  | #define SDL_COPY_MODULATE_ALPHA     0x00000002 | 
|  | #define SDL_COPY_BLEND              0x00000010 | 
|  | #define SDL_COPY_ADD                0x00000020 | 
|  | #define SDL_COPY_MOD                0x00000040 | 
|  | #define SDL_COPY_MUL                0x00000080 | 
|  | #define SDL_COPY_COLORKEY           0x00000100 | 
|  | #define SDL_COPY_NEAREST            0x00000200 | 
|  | #define SDL_COPY_RLE_DESIRED        0x00001000 | 
|  | #define SDL_COPY_RLE_COLORKEY       0x00002000 | 
|  | #define SDL_COPY_RLE_ALPHAKEY       0x00004000 | 
|  | #define SDL_COPY_RLE_MASK           (SDL_COPY_RLE_DESIRED|SDL_COPY_RLE_COLORKEY|SDL_COPY_RLE_ALPHAKEY) | 
|  |  | 
|  | /* SDL blit CPU flags */ | 
|  | #define SDL_CPU_ANY                 0x00000000 | 
|  | #define SDL_CPU_MMX                 0x00000001 | 
|  | #define SDL_CPU_3DNOW               0x00000002 | 
|  | #define SDL_CPU_SSE                 0x00000004 | 
|  | #define SDL_CPU_SSE2                0x00000008 | 
|  | #define SDL_CPU_ALTIVEC_PREFETCH    0x00000010 | 
|  | #define SDL_CPU_ALTIVEC_NOPREFETCH  0x00000020 | 
|  |  | 
|  | typedef struct | 
|  | { | 
|  | Uint8 *src; | 
|  | int src_w, src_h; | 
|  | int src_pitch; | 
|  | int src_skip; | 
|  | Uint8 *dst; | 
|  | int dst_w, dst_h; | 
|  | int dst_pitch; | 
|  | int dst_skip; | 
|  | SDL_PixelFormat *src_fmt; | 
|  | SDL_PixelFormat *dst_fmt; | 
|  | Uint8 *table; | 
|  | int flags; | 
|  | Uint32 colorkey; | 
|  | Uint8 r, g, b, a; | 
|  | } SDL_BlitInfo; | 
|  |  | 
|  | typedef void (*SDL_BlitFunc) (SDL_BlitInfo *info); | 
|  |  | 
|  |  | 
|  | typedef struct | 
|  | { | 
|  | Uint32 src_format; | 
|  | Uint32 dst_format; | 
|  | int flags; | 
|  | int cpu; | 
|  | SDL_BlitFunc func; | 
|  | } SDL_BlitFuncEntry; | 
|  |  | 
|  | /* Blit mapping definition */ | 
|  | typedef struct SDL_BlitMap | 
|  | { | 
|  | SDL_Surface *dst; | 
|  | int identity; | 
|  | SDL_blit blit; | 
|  | void *data; | 
|  | SDL_BlitInfo info; | 
|  |  | 
|  | /* the version count matches the destination; mismatch indicates | 
|  | an invalid mapping */ | 
|  | Uint32 dst_palette_version; | 
|  | Uint32 src_palette_version; | 
|  | } SDL_BlitMap; | 
|  |  | 
|  | /* Functions found in SDL_blit.c */ | 
|  | extern int SDL_CalculateBlit(SDL_Surface * surface); | 
|  |  | 
|  | /* Functions found in SDL_blit_*.c */ | 
|  | extern SDL_BlitFunc SDL_CalculateBlit0(SDL_Surface * surface); | 
|  | extern SDL_BlitFunc SDL_CalculateBlit1(SDL_Surface * surface); | 
|  | extern SDL_BlitFunc SDL_CalculateBlitN(SDL_Surface * surface); | 
|  | extern SDL_BlitFunc SDL_CalculateBlitA(SDL_Surface * surface); | 
|  |  | 
|  | /* | 
|  | * Useful macros for blitting routines | 
|  | */ | 
|  |  | 
|  | #if defined(__GNUC__) | 
|  | #define DECLARE_ALIGNED(t,v,a)  t __attribute__((aligned(a))) v | 
|  | #elif defined(_MSC_VER) | 
|  | #define DECLARE_ALIGNED(t,v,a)  __declspec(align(a)) t v | 
|  | #else | 
|  | #define DECLARE_ALIGNED(t,v,a)  t v | 
|  | #endif | 
|  |  | 
|  | /* Load pixel of the specified format from a buffer and get its R-G-B values */ | 
|  | #define RGB_FROM_PIXEL(Pixel, fmt, r, g, b)                             \ | 
|  | {                                                                       \ | 
|  | r = SDL_expand_byte[fmt->Rloss][((Pixel&fmt->Rmask)>>fmt->Rshift)]; \ | 
|  | g = SDL_expand_byte[fmt->Gloss][((Pixel&fmt->Gmask)>>fmt->Gshift)]; \ | 
|  | b = SDL_expand_byte[fmt->Bloss][((Pixel&fmt->Bmask)>>fmt->Bshift)]; \ | 
|  | } | 
|  | #define RGB_FROM_RGB565(Pixel, r, g, b)                                 \ | 
|  | {                                                                       \ | 
|  | r = SDL_expand_byte[3][((Pixel&0xF800)>>11)];                       \ | 
|  | g = SDL_expand_byte[2][((Pixel&0x07E0)>>5)];                        \ | 
|  | b = SDL_expand_byte[3][(Pixel&0x001F)];                             \ | 
|  | } | 
|  | #define RGB_FROM_RGB555(Pixel, r, g, b)                                 \ | 
|  | {                                                                       \ | 
|  | r = SDL_expand_byte[3][((Pixel&0x7C00)>>10)];                       \ | 
|  | g = SDL_expand_byte[3][((Pixel&0x03E0)>>5)];                        \ | 
|  | b = SDL_expand_byte[3][(Pixel&0x001F)];                             \ | 
|  | } | 
|  | #define RGB_FROM_RGB888(Pixel, r, g, b)                                 \ | 
|  | {                                                                       \ | 
|  | r = ((Pixel&0xFF0000)>>16);                                         \ | 
|  | g = ((Pixel&0xFF00)>>8);                                            \ | 
|  | b = (Pixel&0xFF);                                                   \ | 
|  | } | 
|  | #define RETRIEVE_RGB_PIXEL(buf, bpp, Pixel)                             \ | 
|  | do {                                                                    \ | 
|  | switch (bpp) {                                                      \ | 
|  | case 1:                                                         \ | 
|  | Pixel = *((Uint8 *)(buf));                                  \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 2:                                                         \ | 
|  | Pixel = *((Uint16 *)(buf));                                 \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 3: {                                                       \ | 
|  | Uint8 *B = (Uint8 *)(buf);                                  \ | 
|  | if (SDL_BYTEORDER == SDL_LIL_ENDIAN) {                      \ | 
|  | Pixel = B[0] + (B[1] << 8) + (B[2] << 16);              \ | 
|  | } else {                                                    \ | 
|  | Pixel = (B[0] << 16) + (B[1] << 8) + B[2];              \ | 
|  | }                                                           \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 4:                                                         \ | 
|  | Pixel = *((Uint32 *)(buf));                                 \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | default:                                                        \ | 
|  | Pixel = 0; /* stop gcc complaints */                    \ | 
|  | break;                                                          \ | 
|  | }                                                                   \ | 
|  | } while (0) | 
|  |  | 
|  | #define DISEMBLE_RGB(buf, bpp, fmt, Pixel, r, g, b)                     \ | 
|  | do {                                                                    \ | 
|  | switch (bpp) {                                                      \ | 
|  | case 1:                                                         \ | 
|  | Pixel = *((Uint8 *)(buf));                                  \ | 
|  | RGB_FROM_PIXEL(Pixel, fmt, r, g, b);                        \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 2:                                                         \ | 
|  | Pixel = *((Uint16 *)(buf));                                 \ | 
|  | RGB_FROM_PIXEL(Pixel, fmt, r, g, b);                        \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 3: {                                                       \ | 
|  | Pixel = 0;                                                  \ | 
|  | if (SDL_BYTEORDER == SDL_LIL_ENDIAN) {                      \ | 
|  | r = *((buf)+fmt->Rshift/8);                             \ | 
|  | g = *((buf)+fmt->Gshift/8);                             \ | 
|  | b = *((buf)+fmt->Bshift/8);                             \ | 
|  | } else {                                                    \ | 
|  | r = *((buf)+2-fmt->Rshift/8);                           \ | 
|  | g = *((buf)+2-fmt->Gshift/8);                           \ | 
|  | b = *((buf)+2-fmt->Bshift/8);                           \ | 
|  | }                                                           \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 4:                                                         \ | 
|  | Pixel = *((Uint32 *)(buf));                                 \ | 
|  | RGB_FROM_PIXEL(Pixel, fmt, r, g, b);                        \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | default:                                                        \ | 
|  | /* stop gcc complaints */                               \ | 
|  | Pixel = 0;                                              \ | 
|  | r = g = b = 0;                                          \ | 
|  | break;                                                          \ | 
|  | }                                                                   \ | 
|  | } while (0) | 
|  |  | 
|  | /* Assemble R-G-B values into a specified pixel format and store them */ | 
|  | #define PIXEL_FROM_RGB(Pixel, fmt, r, g, b)                             \ | 
|  | {                                                                       \ | 
|  | Pixel = ((r>>fmt->Rloss)<<fmt->Rshift)|                             \ | 
|  | ((g>>fmt->Gloss)<<fmt->Gshift)|                                 \ | 
|  | ((b>>fmt->Bloss)<<fmt->Bshift)|                                 \ | 
|  | fmt->Amask;                                                     \ | 
|  | } | 
|  | #define RGB565_FROM_RGB(Pixel, r, g, b)                                 \ | 
|  | {                                                                       \ | 
|  | Pixel = ((r>>3)<<11)|((g>>2)<<5)|(b>>3);                            \ | 
|  | } | 
|  | #define RGB555_FROM_RGB(Pixel, r, g, b)                                 \ | 
|  | {                                                                       \ | 
|  | Pixel = ((r>>3)<<10)|((g>>3)<<5)|(b>>3);                            \ | 
|  | } | 
|  | #define RGB888_FROM_RGB(Pixel, r, g, b)                                 \ | 
|  | {                                                                       \ | 
|  | Pixel = (r<<16)|(g<<8)|b;                                           \ | 
|  | } | 
|  | #define ARGB8888_FROM_RGBA(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | Pixel = (a<<24)|(r<<16)|(g<<8)|b;                                   \ | 
|  | } | 
|  | #define RGBA8888_FROM_RGBA(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | Pixel = (r<<24)|(g<<16)|(b<<8)|a;                                   \ | 
|  | } | 
|  | #define ABGR8888_FROM_RGBA(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | Pixel = (a<<24)|(b<<16)|(g<<8)|r;                                   \ | 
|  | } | 
|  | #define BGRA8888_FROM_RGBA(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | Pixel = (b<<24)|(g<<16)|(r<<8)|a;                                   \ | 
|  | } | 
|  | #define ARGB2101010_FROM_RGBA(Pixel, r, g, b, a)                        \ | 
|  | {                                                                       \ | 
|  | r = r ? ((r << 2) | 0x3) : 0;                                       \ | 
|  | g = g ? ((g << 2) | 0x3) : 0;                                       \ | 
|  | b = b ? ((b << 2) | 0x3) : 0;                                       \ | 
|  | a = (a * 3) / 255;                                                  \ | 
|  | Pixel = (a<<30)|(r<<20)|(g<<10)|b;                                  \ | 
|  | } | 
|  | #define ASSEMBLE_RGB(buf, bpp, fmt, r, g, b)                            \ | 
|  | {                                                                       \ | 
|  | switch (bpp) {                                                      \ | 
|  | case 1: {                                                       \ | 
|  | Uint8 _Pixel;                                               \ | 
|  | \ | 
|  | PIXEL_FROM_RGB(_Pixel, fmt, r, g, b);                       \ | 
|  | *((Uint8 *)(buf)) = _Pixel;                                 \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 2: {                                                       \ | 
|  | Uint16 _Pixel;                                              \ | 
|  | \ | 
|  | PIXEL_FROM_RGB(_Pixel, fmt, r, g, b);                       \ | 
|  | *((Uint16 *)(buf)) = _Pixel;                                \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 3: {                                                       \ | 
|  | if (SDL_BYTEORDER == SDL_LIL_ENDIAN) {                      \ | 
|  | *((buf)+fmt->Rshift/8) = r;                             \ | 
|  | *((buf)+fmt->Gshift/8) = g;                             \ | 
|  | *((buf)+fmt->Bshift/8) = b;                             \ | 
|  | } else {                                                    \ | 
|  | *((buf)+2-fmt->Rshift/8) = r;                           \ | 
|  | *((buf)+2-fmt->Gshift/8) = g;                           \ | 
|  | *((buf)+2-fmt->Bshift/8) = b;                           \ | 
|  | }                                                           \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 4: {                                                       \ | 
|  | Uint32 _Pixel;                                              \ | 
|  | \ | 
|  | PIXEL_FROM_RGB(_Pixel, fmt, r, g, b);                       \ | 
|  | *((Uint32 *)(buf)) = _Pixel;                                \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | }                                                                   \ | 
|  | } | 
|  |  | 
|  | /* FIXME: Should we rescale alpha into 0..255 here? */ | 
|  | #define RGBA_FROM_PIXEL(Pixel, fmt, r, g, b, a)                         \ | 
|  | {                                                                       \ | 
|  | r = SDL_expand_byte[fmt->Rloss][((Pixel&fmt->Rmask)>>fmt->Rshift)]; \ | 
|  | g = SDL_expand_byte[fmt->Gloss][((Pixel&fmt->Gmask)>>fmt->Gshift)]; \ | 
|  | b = SDL_expand_byte[fmt->Bloss][((Pixel&fmt->Bmask)>>fmt->Bshift)]; \ | 
|  | a = SDL_expand_byte[fmt->Aloss][((Pixel&fmt->Amask)>>fmt->Ashift)]; \ | 
|  | } | 
|  | #define RGBA_FROM_8888(Pixel, fmt, r, g, b, a)                          \ | 
|  | {                                                                       \ | 
|  | r = (Pixel&fmt->Rmask)>>fmt->Rshift;                                \ | 
|  | g = (Pixel&fmt->Gmask)>>fmt->Gshift;                                \ | 
|  | b = (Pixel&fmt->Bmask)>>fmt->Bshift;                                \ | 
|  | a = (Pixel&fmt->Amask)>>fmt->Ashift;                                \ | 
|  | } | 
|  | #define RGBA_FROM_RGBA8888(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | r = (Pixel>>24);                                                    \ | 
|  | g = ((Pixel>>16)&0xFF);                                             \ | 
|  | b = ((Pixel>>8)&0xFF);                                              \ | 
|  | a = (Pixel&0xFF);                                                   \ | 
|  | } | 
|  | #define RGBA_FROM_ARGB8888(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | r = ((Pixel>>16)&0xFF);                                             \ | 
|  | g = ((Pixel>>8)&0xFF);                                              \ | 
|  | b = (Pixel&0xFF);                                                   \ | 
|  | a = (Pixel>>24);                                                    \ | 
|  | } | 
|  | #define RGBA_FROM_ABGR8888(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | r = (Pixel&0xFF);                                                   \ | 
|  | g = ((Pixel>>8)&0xFF);                                              \ | 
|  | b = ((Pixel>>16)&0xFF);                                             \ | 
|  | a = (Pixel>>24);                                                    \ | 
|  | } | 
|  | #define RGBA_FROM_BGRA8888(Pixel, r, g, b, a)                           \ | 
|  | {                                                                       \ | 
|  | r = ((Pixel>>8)&0xFF);                                              \ | 
|  | g = ((Pixel>>16)&0xFF);                                             \ | 
|  | b = (Pixel>>24);                                                    \ | 
|  | a = (Pixel&0xFF);                                                   \ | 
|  | } | 
|  | #define RGBA_FROM_ARGB2101010(Pixel, r, g, b, a)                        \ | 
|  | {                                                                       \ | 
|  | r = ((Pixel>>22)&0xFF);                                             \ | 
|  | g = ((Pixel>>12)&0xFF);                                             \ | 
|  | b = ((Pixel>>2)&0xFF);                                              \ | 
|  | a = SDL_expand_byte[6][(Pixel>>30)];                                \ | 
|  | } | 
|  | #define DISEMBLE_RGBA(buf, bpp, fmt, Pixel, r, g, b, a)                 \ | 
|  | do {                                                                    \ | 
|  | switch (bpp) {                                                      \ | 
|  | case 1:                                                         \ | 
|  | Pixel = *((Uint8 *)(buf));                                  \ | 
|  | RGBA_FROM_PIXEL(Pixel, fmt, r, g, b, a);                    \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 2:                                                         \ | 
|  | Pixel = *((Uint16 *)(buf));                                 \ | 
|  | RGBA_FROM_PIXEL(Pixel, fmt, r, g, b, a);                    \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 3: {                                                       \ | 
|  | Pixel = 0;                                                  \ | 
|  | if (SDL_BYTEORDER == SDL_LIL_ENDIAN) {                      \ | 
|  | r = *((buf)+fmt->Rshift/8);                             \ | 
|  | g = *((buf)+fmt->Gshift/8);                             \ | 
|  | b = *((buf)+fmt->Bshift/8);                             \ | 
|  | } else {                                                    \ | 
|  | r = *((buf)+2-fmt->Rshift/8);                           \ | 
|  | g = *((buf)+2-fmt->Gshift/8);                           \ | 
|  | b = *((buf)+2-fmt->Bshift/8);                           \ | 
|  | }                                                           \ | 
|  | a = 0xFF;                                                   \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 4:                                                         \ | 
|  | Pixel = *((Uint32 *)(buf));                                 \ | 
|  | RGBA_FROM_PIXEL(Pixel, fmt, r, g, b, a);                    \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | default:                                                        \ | 
|  | /* stop gcc complaints */                                   \ | 
|  | Pixel = 0;                                                  \ | 
|  | r = g = b = a = 0;                                          \ | 
|  | break;                                                          \ | 
|  | }                                                                   \ | 
|  | } while (0) | 
|  |  | 
|  | /* FIXME: this isn't correct, especially for Alpha (maximum != 255) */ | 
|  | #define PIXEL_FROM_RGBA(Pixel, fmt, r, g, b, a)                         \ | 
|  | {                                                                       \ | 
|  | Pixel = ((r>>fmt->Rloss)<<fmt->Rshift)|                             \ | 
|  | ((g>>fmt->Gloss)<<fmt->Gshift)|                                 \ | 
|  | ((b>>fmt->Bloss)<<fmt->Bshift)|                                 \ | 
|  | ((a>>fmt->Aloss)<<fmt->Ashift);                                 \ | 
|  | } | 
|  | #define ASSEMBLE_RGBA(buf, bpp, fmt, r, g, b, a)                        \ | 
|  | {                                                                       \ | 
|  | switch (bpp) {                                                      \ | 
|  | case 1: {                                                       \ | 
|  | Uint8 _pixel;                                               \ | 
|  | \ | 
|  | PIXEL_FROM_RGBA(_pixel, fmt, r, g, b, a);                   \ | 
|  | *((Uint8 *)(buf)) = _pixel;                                 \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 2: {                                                       \ | 
|  | Uint16 _pixel;                                              \ | 
|  | \ | 
|  | PIXEL_FROM_RGBA(_pixel, fmt, r, g, b, a);                   \ | 
|  | *((Uint16 *)(buf)) = _pixel;                                \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 3: {                                                       \ | 
|  | if (SDL_BYTEORDER == SDL_LIL_ENDIAN) {                      \ | 
|  | *((buf)+fmt->Rshift/8) = r;                             \ | 
|  | *((buf)+fmt->Gshift/8) = g;                             \ | 
|  | *((buf)+fmt->Bshift/8) = b;                             \ | 
|  | } else {                                                    \ | 
|  | *((buf)+2-fmt->Rshift/8) = r;                           \ | 
|  | *((buf)+2-fmt->Gshift/8) = g;                           \ | 
|  | *((buf)+2-fmt->Bshift/8) = b;                           \ | 
|  | }                                                           \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | \ | 
|  | case 4: {                                                       \ | 
|  | Uint32 _pixel;                                              \ | 
|  | \ | 
|  | PIXEL_FROM_RGBA(_pixel, fmt, r, g, b, a);                   \ | 
|  | *((Uint32 *)(buf)) = _pixel;                                \ | 
|  | }                                                               \ | 
|  | break;                                                          \ | 
|  | }                                                                   \ | 
|  | } | 
|  |  | 
|  | /* Blend the RGB values of two pixels with an alpha value */ | 
|  | #define ALPHA_BLEND_RGB(sR, sG, sB, A, dR, dG, dB)                      \ | 
|  | do {                                                                    \ | 
|  | dR = (Uint8)((((int)(sR-dR)*(int)A)/255)+dR);                       \ | 
|  | dG = (Uint8)((((int)(sG-dG)*(int)A)/255)+dG);                       \ | 
|  | dB = (Uint8)((((int)(sB-dB)*(int)A)/255)+dB);                       \ | 
|  | } while(0) | 
|  |  | 
|  |  | 
|  | /* Blend the RGBA values of two pixels */ | 
|  | #define ALPHA_BLEND_RGBA(sR, sG, sB, sA, dR, dG, dB, dA)                \ | 
|  | do {                                                                    \ | 
|  | dR = (Uint8)((((int)(sR-dR)*(int)sA)/255)+dR);                      \ | 
|  | dG = (Uint8)((((int)(sG-dG)*(int)sA)/255)+dG);                      \ | 
|  | dB = (Uint8)((((int)(sB-dB)*(int)sA)/255)+dB);                      \ | 
|  | dA = (Uint8)((int)sA+dA-((int)sA*dA)/255);                          \ | 
|  | } while(0) | 
|  |  | 
|  |  | 
|  | /* This is a very useful loop for optimizing blitters */ | 
|  | #if defined(_MSC_VER) && (_MSC_VER == 1300) | 
|  | /* There's a bug in the Visual C++ 7 optimizer when compiling this code */ | 
|  | #else | 
|  | #define USE_DUFFS_LOOP | 
|  | #endif | 
|  | #ifdef USE_DUFFS_LOOP | 
|  |  | 
|  | /* 8-times unrolled loop */ | 
|  | #define DUFFS_LOOP8(pixel_copy_increment, width)                        \ | 
|  | { int n = (width+7)/8;                                                  \ | 
|  | switch (width & 7) {                                                \ | 
|  | case 0: do {    pixel_copy_increment; /* fallthrough */             \ | 
|  | case 7:     pixel_copy_increment;     /* fallthrough */             \ | 
|  | case 6:     pixel_copy_increment;     /* fallthrough */             \ | 
|  | case 5:     pixel_copy_increment;     /* fallthrough */             \ | 
|  | case 4:     pixel_copy_increment;     /* fallthrough */             \ | 
|  | case 3:     pixel_copy_increment;     /* fallthrough */             \ | 
|  | case 2:     pixel_copy_increment;     /* fallthrough */             \ | 
|  | case 1:     pixel_copy_increment;     /* fallthrough */             \ | 
|  | } while ( --n > 0 );                                            \ | 
|  | }                                                                   \ | 
|  | } | 
|  |  | 
|  | /* 4-times unrolled loop */ | 
|  | #define DUFFS_LOOP4(pixel_copy_increment, width)                        \ | 
|  | { int n = (width+3)/4;                                                  \ | 
|  | switch (width & 3) {                                                \ | 
|  | case 0: do {    pixel_copy_increment;   /* fallthrough */           \ | 
|  | case 3:     pixel_copy_increment;       /* fallthrough */           \ | 
|  | case 2:     pixel_copy_increment;       /* fallthrough */           \ | 
|  | case 1:     pixel_copy_increment;       /* fallthrough */           \ | 
|  | } while (--n > 0);                                              \ | 
|  | }                                                                   \ | 
|  | } | 
|  |  | 
|  | /* Use the 8-times version of the loop by default */ | 
|  | #define DUFFS_LOOP(pixel_copy_increment, width)                         \ | 
|  | DUFFS_LOOP8(pixel_copy_increment, width) | 
|  |  | 
|  | /* Special version of Duff's device for even more optimization */ | 
|  | #define DUFFS_LOOP_124(pixel_copy_increment1,                           \ | 
|  | pixel_copy_increment2,                           \ | 
|  | pixel_copy_increment4, width)                    \ | 
|  | { int n = width;                                                        \ | 
|  | if (n & 1) {                                                        \ | 
|  | pixel_copy_increment1; n -= 1;                                  \ | 
|  | }                                                                   \ | 
|  | if (n & 2) {                                                        \ | 
|  | pixel_copy_increment2; n -= 2;                                  \ | 
|  | }                                                                   \ | 
|  | if (n & 4) {                                                        \ | 
|  | pixel_copy_increment4; n -= 4;                                  \ | 
|  | }                                                                   \ | 
|  | if (n) {                                                            \ | 
|  | n /= 8;                                                         \ | 
|  | do {                                                            \ | 
|  | pixel_copy_increment4;                                      \ | 
|  | pixel_copy_increment4;                                      \ | 
|  | } while (--n > 0);                                              \ | 
|  | }                                                                   \ | 
|  | } | 
|  |  | 
|  | #else | 
|  |  | 
|  | /* Don't use Duff's device to unroll loops */ | 
|  | #define DUFFS_LOOP(pixel_copy_increment, width)                         \ | 
|  | { int n;                                                                \ | 
|  | for ( n=width; n > 0; --n ) {                                       \ | 
|  | pixel_copy_increment;                                           \ | 
|  | }                                                                   \ | 
|  | } | 
|  | #define DUFFS_LOOP8(pixel_copy_increment, width)                        \ | 
|  | DUFFS_LOOP(pixel_copy_increment, width) | 
|  | #define DUFFS_LOOP4(pixel_copy_increment, width)                        \ | 
|  | DUFFS_LOOP(pixel_copy_increment, width) | 
|  | #define DUFFS_LOOP_124(pixel_copy_increment1,                           \ | 
|  | pixel_copy_increment2,                           \ | 
|  | pixel_copy_increment4, width)                    \ | 
|  | DUFFS_LOOP(pixel_copy_increment1, width) | 
|  |  | 
|  | #endif /* USE_DUFFS_LOOP */ | 
|  |  | 
|  | /* Prevent Visual C++ 6.0 from printing out stupid warnings */ | 
|  | #if defined(_MSC_VER) && (_MSC_VER >= 600) | 
|  | #pragma warning(disable: 4550) | 
|  | #endif | 
|  |  | 
|  | #endif /* SDL_blit_h_ */ | 
|  |  | 
|  | /* vi: set ts=4 sw=4 expandtab: */ |