mirror of https://github.com/encounter/SDL.git
1231 lines
34 KiB
C
1231 lines
34 KiB
C
/*
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Simple DirectMedia Layer
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Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
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This software is provided 'as-is', without any express or implied
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warranty. In no event will the authors be held liable for any damages
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arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
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including commercial applications, and to alter it and redistribute it
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freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
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claim that you wrote the original software. If you use this software
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in a product, an acknowledgment in the product documentation would be
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appreciated but is not required.
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2. Altered source versions must be plainly marked as such, and must not be
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misrepresented as being the original software.
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3. This notice may not be removed or altered from any source distribution.
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*/
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#include "../SDL_internal.h"
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/* General (mostly internal) pixel/color manipulation routines for SDL */
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#include "SDL_endian.h"
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#include "SDL_video.h"
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#include "SDL_sysvideo.h"
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#include "SDL_blit.h"
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#include "SDL_pixels_c.h"
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#include "SDL_RLEaccel_c.h"
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/* Lookup tables to expand partial bytes to the full 0..255 range */
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static Uint8 lookup_0[] = {
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255
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};
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static Uint8 lookup_1[] = {
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0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 146, 148, 150, 152, 154, 156, 158, 160, 162, 164, 166, 168, 170, 172, 174, 176, 178, 180, 182, 184, 186, 188, 190, 192, 194, 196, 198, 200, 202, 204, 206, 208, 210, 212, 214, 216, 218, 220, 222, 224, 226, 228, 230, 232, 234, 236, 238, 240, 242, 244, 246, 248, 250, 252, 255
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};
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static Uint8 lookup_2[] = {
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0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 170, 174, 178, 182, 186, 190, 194, 198, 202, 206, 210, 214, 218, 222, 226, 230, 234, 238, 242, 246, 250, 255
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};
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static Uint8 lookup_3[] = {
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0, 8, 16, 24, 32, 41, 49, 57, 65, 74, 82, 90, 98, 106, 115, 123, 131, 139, 148, 156, 164, 172, 180, 189, 197, 205, 213, 222, 230, 238, 246, 255
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};
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static Uint8 lookup_4[] = {
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0, 17, 34, 51, 68, 85, 102, 119, 136, 153, 170, 187, 204, 221, 238, 255
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};
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static Uint8 lookup_5[] = {
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0, 36, 72, 109, 145, 182, 218, 255
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};
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static Uint8 lookup_6[] = {
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0, 85, 170, 255
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};
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static Uint8 lookup_7[] = {
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0, 255
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};
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static Uint8 lookup_8[] = {
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255
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};
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Uint8* SDL_expand_byte[9] = {
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lookup_0,
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lookup_1,
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lookup_2,
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lookup_3,
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lookup_4,
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lookup_5,
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lookup_6,
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lookup_7,
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lookup_8
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};
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/* Helper functions */
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const char*
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SDL_GetPixelFormatName(Uint32 format)
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{
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switch (format) {
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#define CASE(X) case X: return #X;
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CASE(SDL_PIXELFORMAT_INDEX1LSB)
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CASE(SDL_PIXELFORMAT_INDEX1MSB)
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CASE(SDL_PIXELFORMAT_INDEX4LSB)
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CASE(SDL_PIXELFORMAT_INDEX4MSB)
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CASE(SDL_PIXELFORMAT_INDEX8)
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CASE(SDL_PIXELFORMAT_RGB332)
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CASE(SDL_PIXELFORMAT_RGB444)
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CASE(SDL_PIXELFORMAT_BGR444)
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CASE(SDL_PIXELFORMAT_RGB555)
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CASE(SDL_PIXELFORMAT_BGR555)
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CASE(SDL_PIXELFORMAT_ARGB4444)
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CASE(SDL_PIXELFORMAT_RGBA4444)
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CASE(SDL_PIXELFORMAT_ABGR4444)
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CASE(SDL_PIXELFORMAT_BGRA4444)
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CASE(SDL_PIXELFORMAT_ARGB1555)
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CASE(SDL_PIXELFORMAT_RGBA5551)
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CASE(SDL_PIXELFORMAT_ABGR1555)
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CASE(SDL_PIXELFORMAT_BGRA5551)
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CASE(SDL_PIXELFORMAT_RGB565)
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CASE(SDL_PIXELFORMAT_BGR565)
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CASE(SDL_PIXELFORMAT_RGB24)
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CASE(SDL_PIXELFORMAT_BGR24)
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CASE(SDL_PIXELFORMAT_RGB888)
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CASE(SDL_PIXELFORMAT_RGBX8888)
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CASE(SDL_PIXELFORMAT_BGR888)
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CASE(SDL_PIXELFORMAT_BGRX8888)
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CASE(SDL_PIXELFORMAT_ARGB8888)
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CASE(SDL_PIXELFORMAT_RGBA8888)
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CASE(SDL_PIXELFORMAT_ABGR8888)
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CASE(SDL_PIXELFORMAT_BGRA8888)
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CASE(SDL_PIXELFORMAT_ARGB2101010)
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CASE(SDL_PIXELFORMAT_YV12)
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CASE(SDL_PIXELFORMAT_IYUV)
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CASE(SDL_PIXELFORMAT_YUY2)
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CASE(SDL_PIXELFORMAT_UYVY)
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CASE(SDL_PIXELFORMAT_YVYU)
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CASE(SDL_PIXELFORMAT_NV12)
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CASE(SDL_PIXELFORMAT_NV21)
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#undef CASE
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default:
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return "SDL_PIXELFORMAT_UNKNOWN";
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}
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}
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SDL_bool
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SDL_PixelFormatEnumToMasks(Uint32 format, int *bpp, Uint32 * Rmask,
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Uint32 * Gmask, Uint32 * Bmask, Uint32 * Amask)
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{
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Uint32 masks[4];
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/* This function doesn't work with FourCC pixel formats */
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if (SDL_ISPIXELFORMAT_FOURCC(format)) {
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SDL_SetError("FOURCC pixel formats are not supported");
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return SDL_FALSE;
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}
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/* Initialize the values here */
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if (SDL_BYTESPERPIXEL(format) <= 2) {
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*bpp = SDL_BITSPERPIXEL(format);
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} else {
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*bpp = SDL_BYTESPERPIXEL(format) * 8;
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}
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*Rmask = *Gmask = *Bmask = *Amask = 0;
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if (format == SDL_PIXELFORMAT_RGB24) {
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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*Rmask = 0x00FF0000;
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*Gmask = 0x0000FF00;
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*Bmask = 0x000000FF;
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#else
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*Rmask = 0x000000FF;
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*Gmask = 0x0000FF00;
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*Bmask = 0x00FF0000;
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#endif
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return SDL_TRUE;
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}
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if (format == SDL_PIXELFORMAT_BGR24) {
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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*Rmask = 0x000000FF;
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*Gmask = 0x0000FF00;
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*Bmask = 0x00FF0000;
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#else
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*Rmask = 0x00FF0000;
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*Gmask = 0x0000FF00;
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*Bmask = 0x000000FF;
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#endif
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return SDL_TRUE;
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}
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if (SDL_PIXELTYPE(format) != SDL_PIXELTYPE_PACKED8 &&
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SDL_PIXELTYPE(format) != SDL_PIXELTYPE_PACKED16 &&
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SDL_PIXELTYPE(format) != SDL_PIXELTYPE_PACKED32) {
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/* Not a format that uses masks */
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return SDL_TRUE;
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}
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switch (SDL_PIXELLAYOUT(format)) {
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case SDL_PACKEDLAYOUT_332:
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masks[0] = 0x00000000;
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masks[1] = 0x000000E0;
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masks[2] = 0x0000001C;
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masks[3] = 0x00000003;
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break;
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case SDL_PACKEDLAYOUT_4444:
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masks[0] = 0x0000F000;
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masks[1] = 0x00000F00;
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masks[2] = 0x000000F0;
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masks[3] = 0x0000000F;
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break;
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case SDL_PACKEDLAYOUT_1555:
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masks[0] = 0x00008000;
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masks[1] = 0x00007C00;
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masks[2] = 0x000003E0;
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masks[3] = 0x0000001F;
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break;
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case SDL_PACKEDLAYOUT_5551:
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masks[0] = 0x0000F800;
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masks[1] = 0x000007C0;
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masks[2] = 0x0000003E;
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masks[3] = 0x00000001;
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break;
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case SDL_PACKEDLAYOUT_565:
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masks[0] = 0x00000000;
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masks[1] = 0x0000F800;
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masks[2] = 0x000007E0;
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masks[3] = 0x0000001F;
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break;
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case SDL_PACKEDLAYOUT_8888:
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masks[0] = 0xFF000000;
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masks[1] = 0x00FF0000;
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masks[2] = 0x0000FF00;
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masks[3] = 0x000000FF;
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break;
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case SDL_PACKEDLAYOUT_2101010:
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masks[0] = 0xC0000000;
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masks[1] = 0x3FF00000;
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masks[2] = 0x000FFC00;
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masks[3] = 0x000003FF;
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break;
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case SDL_PACKEDLAYOUT_1010102:
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masks[0] = 0xFFC00000;
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masks[1] = 0x003FF000;
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masks[2] = 0x00000FFC;
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masks[3] = 0x00000003;
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break;
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default:
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SDL_SetError("Unknown pixel format");
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return SDL_FALSE;
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}
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switch (SDL_PIXELORDER(format)) {
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case SDL_PACKEDORDER_XRGB:
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*Rmask = masks[1];
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*Gmask = masks[2];
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*Bmask = masks[3];
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break;
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case SDL_PACKEDORDER_RGBX:
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*Rmask = masks[0];
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*Gmask = masks[1];
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*Bmask = masks[2];
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break;
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case SDL_PACKEDORDER_ARGB:
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*Amask = masks[0];
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*Rmask = masks[1];
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*Gmask = masks[2];
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*Bmask = masks[3];
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break;
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case SDL_PACKEDORDER_RGBA:
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*Rmask = masks[0];
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*Gmask = masks[1];
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*Bmask = masks[2];
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*Amask = masks[3];
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break;
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case SDL_PACKEDORDER_XBGR:
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*Bmask = masks[1];
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*Gmask = masks[2];
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*Rmask = masks[3];
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break;
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case SDL_PACKEDORDER_BGRX:
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*Bmask = masks[0];
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*Gmask = masks[1];
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*Rmask = masks[2];
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break;
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case SDL_PACKEDORDER_BGRA:
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*Bmask = masks[0];
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*Gmask = masks[1];
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*Rmask = masks[2];
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*Amask = masks[3];
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break;
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case SDL_PACKEDORDER_ABGR:
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*Amask = masks[0];
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*Bmask = masks[1];
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*Gmask = masks[2];
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*Rmask = masks[3];
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break;
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default:
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SDL_SetError("Unknown pixel format");
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return SDL_FALSE;
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}
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return SDL_TRUE;
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}
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Uint32
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SDL_MasksToPixelFormatEnum(int bpp, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask,
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Uint32 Amask)
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{
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switch (bpp) {
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case 1:
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/* SDL defaults to MSB ordering */
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return SDL_PIXELFORMAT_INDEX1MSB;
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case 4:
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/* SDL defaults to MSB ordering */
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return SDL_PIXELFORMAT_INDEX4MSB;
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case 8:
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if (Rmask == 0) {
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return SDL_PIXELFORMAT_INDEX8;
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}
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if (Rmask == 0xE0 &&
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Gmask == 0x1C &&
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Bmask == 0x03 &&
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Amask == 0x00) {
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return SDL_PIXELFORMAT_RGB332;
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}
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break;
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case 12:
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if (Rmask == 0) {
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return SDL_PIXELFORMAT_RGB444;
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}
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if (Rmask == 0x0F00 &&
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Gmask == 0x00F0 &&
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Bmask == 0x000F &&
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Amask == 0x0000) {
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return SDL_PIXELFORMAT_RGB444;
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}
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if (Rmask == 0x000F &&
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Gmask == 0x00F0 &&
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Bmask == 0x0F00 &&
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Amask == 0x0000) {
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return SDL_PIXELFORMAT_BGR444;
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}
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break;
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case 15:
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if (Rmask == 0) {
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return SDL_PIXELFORMAT_RGB555;
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}
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/* fallthrough */
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case 16:
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if (Rmask == 0) {
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return SDL_PIXELFORMAT_RGB565;
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}
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if (Rmask == 0x7C00 &&
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Gmask == 0x03E0 &&
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Bmask == 0x001F &&
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Amask == 0x0000) {
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return SDL_PIXELFORMAT_RGB555;
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}
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if (Rmask == 0x001F &&
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Gmask == 0x03E0 &&
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Bmask == 0x7C00 &&
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Amask == 0x0000) {
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return SDL_PIXELFORMAT_BGR555;
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}
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if (Rmask == 0x0F00 &&
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Gmask == 0x00F0 &&
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Bmask == 0x000F &&
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Amask == 0xF000) {
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return SDL_PIXELFORMAT_ARGB4444;
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}
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if (Rmask == 0xF000 &&
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Gmask == 0x0F00 &&
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Bmask == 0x00F0 &&
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Amask == 0x000F) {
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return SDL_PIXELFORMAT_RGBA4444;
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}
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if (Rmask == 0x000F &&
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Gmask == 0x00F0 &&
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Bmask == 0x0F00 &&
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Amask == 0xF000) {
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return SDL_PIXELFORMAT_ABGR4444;
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}
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if (Rmask == 0x00F0 &&
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Gmask == 0x0F00 &&
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Bmask == 0xF000 &&
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Amask == 0x000F) {
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return SDL_PIXELFORMAT_BGRA4444;
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}
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if (Rmask == 0x7C00 &&
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Gmask == 0x03E0 &&
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Bmask == 0x001F &&
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Amask == 0x8000) {
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return SDL_PIXELFORMAT_ARGB1555;
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}
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if (Rmask == 0xF800 &&
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Gmask == 0x07C0 &&
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Bmask == 0x003E &&
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Amask == 0x0001) {
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return SDL_PIXELFORMAT_RGBA5551;
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}
|
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if (Rmask == 0x001F &&
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Gmask == 0x03E0 &&
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Bmask == 0x7C00 &&
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Amask == 0x8000) {
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return SDL_PIXELFORMAT_ABGR1555;
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}
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if (Rmask == 0x003E &&
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Gmask == 0x07C0 &&
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Bmask == 0xF800 &&
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Amask == 0x0001) {
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return SDL_PIXELFORMAT_BGRA5551;
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}
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if (Rmask == 0xF800 &&
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Gmask == 0x07E0 &&
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Bmask == 0x001F &&
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Amask == 0x0000) {
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return SDL_PIXELFORMAT_RGB565;
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}
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if (Rmask == 0x001F &&
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Gmask == 0x07E0 &&
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Bmask == 0xF800 &&
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|
Amask == 0x0000) {
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return SDL_PIXELFORMAT_BGR565;
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}
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if (Rmask == 0x003F &&
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Gmask == 0x07C0 &&
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Bmask == 0xF800 &&
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Amask == 0x0000) {
|
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/* Technically this would be BGR556, but Witek says this works in bug 3158 */
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return SDL_PIXELFORMAT_RGB565;
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}
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break;
|
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case 24:
|
|
switch (Rmask) {
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case 0:
|
|
case 0x00FF0000:
|
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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return SDL_PIXELFORMAT_RGB24;
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#else
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return SDL_PIXELFORMAT_BGR24;
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#endif
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case 0x000000FF:
|
|
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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return SDL_PIXELFORMAT_BGR24;
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#else
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return SDL_PIXELFORMAT_RGB24;
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#endif
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}
|
|
case 32:
|
|
if (Rmask == 0) {
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return SDL_PIXELFORMAT_RGB888;
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|
}
|
|
if (Rmask == 0x00FF0000 &&
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Gmask == 0x0000FF00 &&
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Bmask == 0x000000FF &&
|
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Amask == 0x00000000) {
|
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return SDL_PIXELFORMAT_RGB888;
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}
|
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if (Rmask == 0xFF000000 &&
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Gmask == 0x00FF0000 &&
|
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Bmask == 0x0000FF00 &&
|
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Amask == 0x00000000) {
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return SDL_PIXELFORMAT_RGBX8888;
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|
}
|
|
if (Rmask == 0x000000FF &&
|
|
Gmask == 0x0000FF00 &&
|
|
Bmask == 0x00FF0000 &&
|
|
Amask == 0x00000000) {
|
|
return SDL_PIXELFORMAT_BGR888;
|
|
}
|
|
if (Rmask == 0x0000FF00 &&
|
|
Gmask == 0x00FF0000 &&
|
|
Bmask == 0xFF000000 &&
|
|
Amask == 0x00000000) {
|
|
return SDL_PIXELFORMAT_BGRX8888;
|
|
}
|
|
if (Rmask == 0x00FF0000 &&
|
|
Gmask == 0x0000FF00 &&
|
|
Bmask == 0x000000FF &&
|
|
Amask == 0xFF000000) {
|
|
return SDL_PIXELFORMAT_ARGB8888;
|
|
}
|
|
if (Rmask == 0xFF000000 &&
|
|
Gmask == 0x00FF0000 &&
|
|
Bmask == 0x0000FF00 &&
|
|
Amask == 0x000000FF) {
|
|
return SDL_PIXELFORMAT_RGBA8888;
|
|
}
|
|
if (Rmask == 0x000000FF &&
|
|
Gmask == 0x0000FF00 &&
|
|
Bmask == 0x00FF0000 &&
|
|
Amask == 0xFF000000) {
|
|
return SDL_PIXELFORMAT_ABGR8888;
|
|
}
|
|
if (Rmask == 0x0000FF00 &&
|
|
Gmask == 0x00FF0000 &&
|
|
Bmask == 0xFF000000 &&
|
|
Amask == 0x000000FF) {
|
|
return SDL_PIXELFORMAT_BGRA8888;
|
|
}
|
|
if (Rmask == 0x3FF00000 &&
|
|
Gmask == 0x000FFC00 &&
|
|
Bmask == 0x000003FF &&
|
|
Amask == 0xC0000000) {
|
|
return SDL_PIXELFORMAT_ARGB2101010;
|
|
}
|
|
}
|
|
return SDL_PIXELFORMAT_UNKNOWN;
|
|
}
|
|
|
|
static SDL_PixelFormat *formats;
|
|
static SDL_SpinLock formats_lock = 0;
|
|
|
|
SDL_PixelFormat *
|
|
SDL_AllocFormat(Uint32 pixel_format)
|
|
{
|
|
SDL_PixelFormat *format;
|
|
|
|
SDL_AtomicLock(&formats_lock);
|
|
|
|
/* Look it up in our list of previously allocated formats */
|
|
for (format = formats; format; format = format->next) {
|
|
if (pixel_format == format->format) {
|
|
++format->refcount;
|
|
SDL_AtomicUnlock(&formats_lock);
|
|
return format;
|
|
}
|
|
}
|
|
|
|
/* Allocate an empty pixel format structure, and initialize it */
|
|
format = SDL_malloc(sizeof(*format));
|
|
if (format == NULL) {
|
|
SDL_AtomicUnlock(&formats_lock);
|
|
SDL_OutOfMemory();
|
|
return NULL;
|
|
}
|
|
if (SDL_InitFormat(format, pixel_format) < 0) {
|
|
SDL_AtomicUnlock(&formats_lock);
|
|
SDL_free(format);
|
|
SDL_InvalidParamError("format");
|
|
return NULL;
|
|
}
|
|
|
|
if (!SDL_ISPIXELFORMAT_INDEXED(pixel_format)) {
|
|
/* Cache the RGB formats */
|
|
format->next = formats;
|
|
formats = format;
|
|
}
|
|
|
|
SDL_AtomicUnlock(&formats_lock);
|
|
|
|
return format;
|
|
}
|
|
|
|
int
|
|
SDL_InitFormat(SDL_PixelFormat * format, Uint32 pixel_format)
|
|
{
|
|
int bpp;
|
|
Uint32 Rmask, Gmask, Bmask, Amask;
|
|
Uint32 mask;
|
|
|
|
if (!SDL_PixelFormatEnumToMasks(pixel_format, &bpp,
|
|
&Rmask, &Gmask, &Bmask, &Amask)) {
|
|
return -1;
|
|
}
|
|
|
|
/* Set up the format */
|
|
SDL_zerop(format);
|
|
format->format = pixel_format;
|
|
format->BitsPerPixel = bpp;
|
|
format->BytesPerPixel = (bpp + 7) / 8;
|
|
|
|
format->Rmask = Rmask;
|
|
format->Rshift = 0;
|
|
format->Rloss = 8;
|
|
if (Rmask) {
|
|
for (mask = Rmask; !(mask & 0x01); mask >>= 1)
|
|
++format->Rshift;
|
|
for (; (mask & 0x01); mask >>= 1)
|
|
--format->Rloss;
|
|
}
|
|
|
|
format->Gmask = Gmask;
|
|
format->Gshift = 0;
|
|
format->Gloss = 8;
|
|
if (Gmask) {
|
|
for (mask = Gmask; !(mask & 0x01); mask >>= 1)
|
|
++format->Gshift;
|
|
for (; (mask & 0x01); mask >>= 1)
|
|
--format->Gloss;
|
|
}
|
|
|
|
format->Bmask = Bmask;
|
|
format->Bshift = 0;
|
|
format->Bloss = 8;
|
|
if (Bmask) {
|
|
for (mask = Bmask; !(mask & 0x01); mask >>= 1)
|
|
++format->Bshift;
|
|
for (; (mask & 0x01); mask >>= 1)
|
|
--format->Bloss;
|
|
}
|
|
|
|
format->Amask = Amask;
|
|
format->Ashift = 0;
|
|
format->Aloss = 8;
|
|
if (Amask) {
|
|
for (mask = Amask; !(mask & 0x01); mask >>= 1)
|
|
++format->Ashift;
|
|
for (; (mask & 0x01); mask >>= 1)
|
|
--format->Aloss;
|
|
}
|
|
|
|
format->palette = NULL;
|
|
format->refcount = 1;
|
|
format->next = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
SDL_FreeFormat(SDL_PixelFormat *format)
|
|
{
|
|
SDL_PixelFormat *prev;
|
|
|
|
if (!format) {
|
|
SDL_InvalidParamError("format");
|
|
return;
|
|
}
|
|
|
|
SDL_AtomicLock(&formats_lock);
|
|
|
|
if (--format->refcount > 0) {
|
|
SDL_AtomicUnlock(&formats_lock);
|
|
return;
|
|
}
|
|
|
|
/* Remove this format from our list */
|
|
if (format == formats) {
|
|
formats = format->next;
|
|
} else if (formats) {
|
|
for (prev = formats; prev->next; prev = prev->next) {
|
|
if (prev->next == format) {
|
|
prev->next = format->next;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
SDL_AtomicUnlock(&formats_lock);
|
|
|
|
if (format->palette) {
|
|
SDL_FreePalette(format->palette);
|
|
}
|
|
SDL_free(format);
|
|
}
|
|
|
|
SDL_Palette *
|
|
SDL_AllocPalette(int ncolors)
|
|
{
|
|
SDL_Palette *palette;
|
|
|
|
/* Input validation */
|
|
if (ncolors < 1) {
|
|
SDL_InvalidParamError("ncolors");
|
|
return NULL;
|
|
}
|
|
|
|
palette = (SDL_Palette *) SDL_malloc(sizeof(*palette));
|
|
if (!palette) {
|
|
SDL_OutOfMemory();
|
|
return NULL;
|
|
}
|
|
palette->colors =
|
|
(SDL_Color *) SDL_malloc(ncolors * sizeof(*palette->colors));
|
|
if (!palette->colors) {
|
|
SDL_free(palette);
|
|
return NULL;
|
|
}
|
|
palette->ncolors = ncolors;
|
|
palette->version = 1;
|
|
palette->refcount = 1;
|
|
|
|
SDL_memset(palette->colors, 0xFF, ncolors * sizeof(*palette->colors));
|
|
|
|
return palette;
|
|
}
|
|
|
|
int
|
|
SDL_SetPixelFormatPalette(SDL_PixelFormat * format, SDL_Palette *palette)
|
|
{
|
|
if (!format) {
|
|
return SDL_SetError("SDL_SetPixelFormatPalette() passed NULL format");
|
|
}
|
|
|
|
if (palette && palette->ncolors > (1 << format->BitsPerPixel)) {
|
|
return SDL_SetError("SDL_SetPixelFormatPalette() passed a palette that doesn't match the format");
|
|
}
|
|
|
|
if (format->palette == palette) {
|
|
return 0;
|
|
}
|
|
|
|
if (format->palette) {
|
|
SDL_FreePalette(format->palette);
|
|
}
|
|
|
|
format->palette = palette;
|
|
|
|
if (format->palette) {
|
|
++format->palette->refcount;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
SDL_SetPaletteColors(SDL_Palette * palette, const SDL_Color * colors,
|
|
int firstcolor, int ncolors)
|
|
{
|
|
int status = 0;
|
|
|
|
/* Verify the parameters */
|
|
if (!palette) {
|
|
return -1;
|
|
}
|
|
if (ncolors > (palette->ncolors - firstcolor)) {
|
|
ncolors = (palette->ncolors - firstcolor);
|
|
status = -1;
|
|
}
|
|
|
|
if (colors != (palette->colors + firstcolor)) {
|
|
SDL_memcpy(palette->colors + firstcolor, colors,
|
|
ncolors * sizeof(*colors));
|
|
}
|
|
++palette->version;
|
|
if (!palette->version) {
|
|
palette->version = 1;
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
void
|
|
SDL_FreePalette(SDL_Palette * palette)
|
|
{
|
|
if (!palette) {
|
|
SDL_InvalidParamError("palette");
|
|
return;
|
|
}
|
|
if (--palette->refcount > 0) {
|
|
return;
|
|
}
|
|
SDL_free(palette->colors);
|
|
SDL_free(palette);
|
|
}
|
|
|
|
/*
|
|
* Calculate an 8-bit (3 red, 3 green, 2 blue) dithered palette of colors
|
|
*/
|
|
void
|
|
SDL_DitherColors(SDL_Color * colors, int bpp)
|
|
{
|
|
int i;
|
|
if (bpp != 8)
|
|
return; /* only 8bpp supported right now */
|
|
|
|
for (i = 0; i < 256; i++) {
|
|
int r, g, b;
|
|
/* map each bit field to the full [0, 255] interval,
|
|
so 0 is mapped to (0, 0, 0) and 255 to (255, 255, 255) */
|
|
r = i & 0xe0;
|
|
r |= r >> 3 | r >> 6;
|
|
colors[i].r = r;
|
|
g = (i << 3) & 0xe0;
|
|
g |= g >> 3 | g >> 6;
|
|
colors[i].g = g;
|
|
b = i & 0x3;
|
|
b |= b << 2;
|
|
b |= b << 4;
|
|
colors[i].b = b;
|
|
colors[i].a = SDL_ALPHA_OPAQUE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Match an RGB value to a particular palette index
|
|
*/
|
|
Uint8
|
|
SDL_FindColor(SDL_Palette * pal, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
|
|
{
|
|
/* Do colorspace distance matching */
|
|
unsigned int smallest;
|
|
unsigned int distance;
|
|
int rd, gd, bd, ad;
|
|
int i;
|
|
Uint8 pixel = 0;
|
|
|
|
smallest = ~0;
|
|
for (i = 0; i < pal->ncolors; ++i) {
|
|
rd = pal->colors[i].r - r;
|
|
gd = pal->colors[i].g - g;
|
|
bd = pal->colors[i].b - b;
|
|
ad = pal->colors[i].a - a;
|
|
distance = (rd * rd) + (gd * gd) + (bd * bd) + (ad * ad);
|
|
if (distance < smallest) {
|
|
pixel = i;
|
|
if (distance == 0) { /* Perfect match! */
|
|
break;
|
|
}
|
|
smallest = distance;
|
|
}
|
|
}
|
|
return (pixel);
|
|
}
|
|
|
|
/* Tell whether palette is opaque, and if it has an alpha_channel */
|
|
void
|
|
SDL_DetectPalette(SDL_Palette *pal, SDL_bool *is_opaque, SDL_bool *has_alpha_channel)
|
|
{
|
|
int i;
|
|
|
|
{
|
|
SDL_bool all_opaque = SDL_TRUE;
|
|
for (i = 0; i < pal->ncolors; i++) {
|
|
Uint8 alpha_value = pal->colors[i].a;
|
|
if (alpha_value != SDL_ALPHA_OPAQUE) {
|
|
all_opaque = SDL_FALSE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (all_opaque) {
|
|
/* Palette is opaque, with an alpha channel */
|
|
*is_opaque = SDL_TRUE;
|
|
*has_alpha_channel = SDL_TRUE;
|
|
return;
|
|
}
|
|
}
|
|
|
|
{
|
|
SDL_bool all_transparent = SDL_TRUE;
|
|
for (i = 0; i < pal->ncolors; i++) {
|
|
Uint8 alpha_value = pal->colors[i].a;
|
|
if (alpha_value != SDL_ALPHA_TRANSPARENT) {
|
|
all_transparent = SDL_FALSE;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (all_transparent) {
|
|
/* Palette is opaque, without an alpha channel */
|
|
*is_opaque = SDL_TRUE;
|
|
*has_alpha_channel = SDL_FALSE;
|
|
return;
|
|
}
|
|
}
|
|
|
|
/* Palette has alpha values */
|
|
*is_opaque = SDL_FALSE;
|
|
*has_alpha_channel = SDL_TRUE;
|
|
}
|
|
|
|
|
|
/* Find the opaque pixel value corresponding to an RGB triple */
|
|
Uint32
|
|
SDL_MapRGB(const SDL_PixelFormat * format, Uint8 r, Uint8 g, Uint8 b)
|
|
{
|
|
if (format->palette == NULL) {
|
|
return (r >> format->Rloss) << format->Rshift
|
|
| (g >> format->Gloss) << format->Gshift
|
|
| (b >> format->Bloss) << format->Bshift | format->Amask;
|
|
} else {
|
|
return SDL_FindColor(format->palette, r, g, b, SDL_ALPHA_OPAQUE);
|
|
}
|
|
}
|
|
|
|
/* Find the pixel value corresponding to an RGBA quadruple */
|
|
Uint32
|
|
SDL_MapRGBA(const SDL_PixelFormat * format, Uint8 r, Uint8 g, Uint8 b,
|
|
Uint8 a)
|
|
{
|
|
if (format->palette == NULL) {
|
|
return (r >> format->Rloss) << format->Rshift
|
|
| (g >> format->Gloss) << format->Gshift
|
|
| (b >> format->Bloss) << format->Bshift
|
|
| ((a >> format->Aloss) << format->Ashift & format->Amask);
|
|
} else {
|
|
return SDL_FindColor(format->palette, r, g, b, a);
|
|
}
|
|
}
|
|
|
|
void
|
|
SDL_GetRGB(Uint32 pixel, const SDL_PixelFormat * format, Uint8 * r, Uint8 * g,
|
|
Uint8 * b)
|
|
{
|
|
if (format->palette == NULL) {
|
|
unsigned v;
|
|
v = (pixel & format->Rmask) >> format->Rshift;
|
|
*r = SDL_expand_byte[format->Rloss][v];
|
|
v = (pixel & format->Gmask) >> format->Gshift;
|
|
*g = SDL_expand_byte[format->Gloss][v];
|
|
v = (pixel & format->Bmask) >> format->Bshift;
|
|
*b = SDL_expand_byte[format->Bloss][v];
|
|
} else {
|
|
if (pixel < (unsigned)format->palette->ncolors) {
|
|
*r = format->palette->colors[pixel].r;
|
|
*g = format->palette->colors[pixel].g;
|
|
*b = format->palette->colors[pixel].b;
|
|
} else {
|
|
*r = *g = *b = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
SDL_GetRGBA(Uint32 pixel, const SDL_PixelFormat * format,
|
|
Uint8 * r, Uint8 * g, Uint8 * b, Uint8 * a)
|
|
{
|
|
if (format->palette == NULL) {
|
|
unsigned v;
|
|
v = (pixel & format->Rmask) >> format->Rshift;
|
|
*r = SDL_expand_byte[format->Rloss][v];
|
|
v = (pixel & format->Gmask) >> format->Gshift;
|
|
*g = SDL_expand_byte[format->Gloss][v];
|
|
v = (pixel & format->Bmask) >> format->Bshift;
|
|
*b = SDL_expand_byte[format->Bloss][v];
|
|
v = (pixel & format->Amask) >> format->Ashift;
|
|
*a = SDL_expand_byte[format->Aloss][v];
|
|
} else {
|
|
if (pixel < (unsigned)format->palette->ncolors) {
|
|
*r = format->palette->colors[pixel].r;
|
|
*g = format->palette->colors[pixel].g;
|
|
*b = format->palette->colors[pixel].b;
|
|
*a = format->palette->colors[pixel].a;
|
|
} else {
|
|
*r = *g = *b = *a = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Map from Palette to Palette */
|
|
static Uint8 *
|
|
Map1to1(SDL_Palette * src, SDL_Palette * dst, int *identical)
|
|
{
|
|
Uint8 *map;
|
|
int i;
|
|
|
|
if (identical) {
|
|
if (src->ncolors <= dst->ncolors) {
|
|
/* If an identical palette, no need to map */
|
|
if (src == dst
|
|
||
|
|
(SDL_memcmp
|
|
(src->colors, dst->colors,
|
|
src->ncolors * sizeof(SDL_Color)) == 0)) {
|
|
*identical = 1;
|
|
return (NULL);
|
|
}
|
|
}
|
|
*identical = 0;
|
|
}
|
|
map = (Uint8 *) SDL_malloc(src->ncolors);
|
|
if (map == NULL) {
|
|
SDL_OutOfMemory();
|
|
return (NULL);
|
|
}
|
|
for (i = 0; i < src->ncolors; ++i) {
|
|
map[i] = SDL_FindColor(dst,
|
|
src->colors[i].r, src->colors[i].g,
|
|
src->colors[i].b, src->colors[i].a);
|
|
}
|
|
return (map);
|
|
}
|
|
|
|
/* Map from Palette to BitField */
|
|
static Uint8 *
|
|
Map1toN(SDL_PixelFormat * src, Uint8 Rmod, Uint8 Gmod, Uint8 Bmod, Uint8 Amod,
|
|
SDL_PixelFormat * dst)
|
|
{
|
|
Uint8 *map;
|
|
int i;
|
|
int bpp;
|
|
SDL_Palette *pal = src->palette;
|
|
|
|
bpp = ((dst->BytesPerPixel == 3) ? 4 : dst->BytesPerPixel);
|
|
map = (Uint8 *) SDL_malloc(pal->ncolors * bpp);
|
|
if (map == NULL) {
|
|
SDL_OutOfMemory();
|
|
return (NULL);
|
|
}
|
|
|
|
/* We memory copy to the pixel map so the endianness is preserved */
|
|
for (i = 0; i < pal->ncolors; ++i) {
|
|
Uint8 R = (Uint8) ((pal->colors[i].r * Rmod) / 255);
|
|
Uint8 G = (Uint8) ((pal->colors[i].g * Gmod) / 255);
|
|
Uint8 B = (Uint8) ((pal->colors[i].b * Bmod) / 255);
|
|
Uint8 A = (Uint8) ((pal->colors[i].a * Amod) / 255);
|
|
ASSEMBLE_RGBA(&map[i * bpp], dst->BytesPerPixel, dst, R, G, B, A);
|
|
}
|
|
return (map);
|
|
}
|
|
|
|
/* Map from BitField to Dithered-Palette to Palette */
|
|
static Uint8 *
|
|
MapNto1(SDL_PixelFormat * src, SDL_PixelFormat * dst, int *identical)
|
|
{
|
|
/* Generate a 256 color dither palette */
|
|
SDL_Palette dithered;
|
|
SDL_Color colors[256];
|
|
SDL_Palette *pal = dst->palette;
|
|
|
|
dithered.ncolors = 256;
|
|
SDL_DitherColors(colors, 8);
|
|
dithered.colors = colors;
|
|
return (Map1to1(&dithered, pal, identical));
|
|
}
|
|
|
|
SDL_BlitMap *
|
|
SDL_AllocBlitMap(void)
|
|
{
|
|
SDL_BlitMap *map;
|
|
|
|
/* Allocate the empty map */
|
|
map = (SDL_BlitMap *) SDL_calloc(1, sizeof(*map));
|
|
if (map == NULL) {
|
|
SDL_OutOfMemory();
|
|
return (NULL);
|
|
}
|
|
map->info.r = 0xFF;
|
|
map->info.g = 0xFF;
|
|
map->info.b = 0xFF;
|
|
map->info.a = 0xFF;
|
|
|
|
/* It's ready to go */
|
|
return (map);
|
|
}
|
|
|
|
|
|
typedef struct SDL_ListNode
|
|
{
|
|
void *entry;
|
|
struct SDL_ListNode *next;
|
|
} SDL_ListNode;
|
|
|
|
void
|
|
SDL_InvalidateAllBlitMap(SDL_Surface *surface)
|
|
{
|
|
SDL_ListNode *l = surface->list_blitmap;
|
|
|
|
surface->list_blitmap = NULL;
|
|
|
|
while (l) {
|
|
SDL_ListNode *tmp = l;
|
|
SDL_InvalidateMap((SDL_BlitMap *)l->entry);
|
|
l = l->next;
|
|
SDL_free(tmp);
|
|
}
|
|
}
|
|
|
|
static void SDL_ListAdd(SDL_ListNode **head, void *ent);
|
|
static void SDL_ListRemove(SDL_ListNode **head, void *ent);
|
|
|
|
void
|
|
SDL_ListAdd(SDL_ListNode **head, void *ent)
|
|
{
|
|
SDL_ListNode *node = SDL_malloc(sizeof (*node));
|
|
|
|
if (node == NULL) {
|
|
SDL_OutOfMemory();
|
|
return;
|
|
}
|
|
|
|
node->entry = ent;
|
|
node->next = *head;
|
|
*head = node;
|
|
}
|
|
|
|
void
|
|
SDL_ListRemove(SDL_ListNode **head, void *ent)
|
|
{
|
|
SDL_ListNode **ptr = head;
|
|
|
|
while (*ptr) {
|
|
if ((*ptr)->entry == ent) {
|
|
SDL_ListNode *tmp = *ptr;
|
|
*ptr = (*ptr)->next;
|
|
SDL_free(tmp);
|
|
return;
|
|
}
|
|
ptr = &(*ptr)->next;
|
|
}
|
|
}
|
|
|
|
void
|
|
SDL_InvalidateMap(SDL_BlitMap * map)
|
|
{
|
|
if (!map) {
|
|
return;
|
|
}
|
|
if (map->dst) {
|
|
/* Un-register from the destination surface */
|
|
SDL_ListRemove((SDL_ListNode **)&(map->dst->list_blitmap), map);
|
|
}
|
|
map->dst = NULL;
|
|
map->src_palette_version = 0;
|
|
map->dst_palette_version = 0;
|
|
SDL_free(map->info.table);
|
|
map->info.table = NULL;
|
|
}
|
|
|
|
int
|
|
SDL_MapSurface(SDL_Surface * src, SDL_Surface * dst)
|
|
{
|
|
SDL_PixelFormat *srcfmt;
|
|
SDL_PixelFormat *dstfmt;
|
|
SDL_BlitMap *map;
|
|
|
|
/* Clear out any previous mapping */
|
|
map = src->map;
|
|
#if SDL_HAVE_RLE
|
|
if ((src->flags & SDL_RLEACCEL) == SDL_RLEACCEL) {
|
|
SDL_UnRLESurface(src, 1);
|
|
}
|
|
#endif
|
|
SDL_InvalidateMap(map);
|
|
|
|
/* Figure out what kind of mapping we're doing */
|
|
map->identity = 0;
|
|
srcfmt = src->format;
|
|
dstfmt = dst->format;
|
|
if (SDL_ISPIXELFORMAT_INDEXED(srcfmt->format)) {
|
|
if (SDL_ISPIXELFORMAT_INDEXED(dstfmt->format)) {
|
|
/* Palette --> Palette */
|
|
map->info.table =
|
|
Map1to1(srcfmt->palette, dstfmt->palette, &map->identity);
|
|
if (!map->identity) {
|
|
if (map->info.table == NULL) {
|
|
return (-1);
|
|
}
|
|
}
|
|
if (srcfmt->BitsPerPixel != dstfmt->BitsPerPixel)
|
|
map->identity = 0;
|
|
} else {
|
|
/* Palette --> BitField */
|
|
map->info.table =
|
|
Map1toN(srcfmt, src->map->info.r, src->map->info.g,
|
|
src->map->info.b, src->map->info.a, dstfmt);
|
|
if (map->info.table == NULL) {
|
|
return (-1);
|
|
}
|
|
}
|
|
} else {
|
|
if (SDL_ISPIXELFORMAT_INDEXED(dstfmt->format)) {
|
|
/* BitField --> Palette */
|
|
map->info.table = MapNto1(srcfmt, dstfmt, &map->identity);
|
|
if (!map->identity) {
|
|
if (map->info.table == NULL) {
|
|
return (-1);
|
|
}
|
|
}
|
|
map->identity = 0; /* Don't optimize to copy */
|
|
} else {
|
|
/* BitField --> BitField */
|
|
if (srcfmt == dstfmt) {
|
|
map->identity = 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
map->dst = dst;
|
|
|
|
if (map->dst) {
|
|
/* Register BlitMap to the destination surface, to be invalidated when needed */
|
|
SDL_ListAdd((SDL_ListNode **)&(map->dst->list_blitmap), map);
|
|
}
|
|
|
|
if (dstfmt->palette) {
|
|
map->dst_palette_version = dstfmt->palette->version;
|
|
} else {
|
|
map->dst_palette_version = 0;
|
|
}
|
|
|
|
if (srcfmt->palette) {
|
|
map->src_palette_version = srcfmt->palette->version;
|
|
} else {
|
|
map->src_palette_version = 0;
|
|
}
|
|
|
|
/* Choose your blitters wisely */
|
|
return (SDL_CalculateBlit(src));
|
|
}
|
|
|
|
void
|
|
SDL_FreeBlitMap(SDL_BlitMap * map)
|
|
{
|
|
if (map) {
|
|
SDL_InvalidateMap(map);
|
|
SDL_free(map);
|
|
}
|
|
}
|
|
|
|
void
|
|
SDL_CalculateGammaRamp(float gamma, Uint16 * ramp)
|
|
{
|
|
int i;
|
|
|
|
/* Input validation */
|
|
if (gamma < 0.0f ) {
|
|
SDL_InvalidParamError("gamma");
|
|
return;
|
|
}
|
|
if (ramp == NULL) {
|
|
SDL_InvalidParamError("ramp");
|
|
return;
|
|
}
|
|
|
|
/* 0.0 gamma is all black */
|
|
if (gamma == 0.0f) {
|
|
SDL_memset(ramp, 0, 256 * sizeof(Uint16));
|
|
return;
|
|
} else if (gamma == 1.0f) {
|
|
/* 1.0 gamma is identity */
|
|
for (i = 0; i < 256; ++i) {
|
|
ramp[i] = (i << 8) | i;
|
|
}
|
|
return;
|
|
} else {
|
|
/* Calculate a real gamma ramp */
|
|
int value;
|
|
gamma = 1.0f / gamma;
|
|
for (i = 0; i < 256; ++i) {
|
|
value =
|
|
(int) (SDL_pow((double) i / 256.0, gamma) * 65535.0 + 0.5);
|
|
if (value > 65535) {
|
|
value = 65535;
|
|
}
|
|
ramp[i] = (Uint16) value;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* vi: set ts=4 sw=4 expandtab: */
|