SDL_atarigl.c
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/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2004 Sam Lantinga
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Sam Lantinga
slouken@libsdl.org
*/
/* Atari OSMesa.ldg implementation of SDL OpenGL support */
/*--- Includes ---*/
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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
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#ifdef HAVE_OPENGL
#include <GL/osmesa.h>
#endif
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#include <mint/osbind.h>
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#include "SDL_video.h"
#include "SDL_error.h"
#include "SDL_endian.h"
#include "SDL_atarigl_c.h"
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#ifdef ENABLE_OSMESA_SHARED
#include "SDL_loadso.h"
#endif
/*--- Defines ---*/
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#define PATH_OSMESA_LDG "osmesa.ldg"
#define PATH_MESAGL_LDG "mesa_gl.ldg"
#define PATH_TINYGL_LDG "tiny_gl.ldg"
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/*--- Functions prototypes ---*/
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static void SDL_AtariGL_UnloadLibrary(_THIS);
static void CopyShadowNull(_THIS, SDL_Surface *surface);
static void CopyShadowDirect(_THIS, SDL_Surface *surface);
static void CopyShadow8888To555(_THIS, SDL_Surface *surface);
static void CopyShadow8888To565(_THIS, SDL_Surface *surface);
static void ConvertNull(_THIS, SDL_Surface *surface);
static void Convert565To555be(_THIS, SDL_Surface *surface);
static void Convert565To555le(_THIS, SDL_Surface *surface);
static void Convert565le(_THIS, SDL_Surface *surface);
static void ConvertBGRAToABGR(_THIS, SDL_Surface *surface);
static int InitNew(_THIS, SDL_Surface *current);
static int InitOld(_THIS, SDL_Surface *current);
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/*--- Public functions ---*/
int SDL_AtariGL_Init(_THIS, SDL_Surface *current)
{
#ifdef HAVE_OPENGL
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if (gl_oldmesa) {
gl_active = InitOld(this, current);
} else {
gl_active = InitNew(this, current);
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return (gl_active);
}
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void SDL_AtariGL_Quit(_THIS, SDL_bool unload)
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{
#ifdef HAVE_OPENGL
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if (gl_oldmesa) {
/* Old mesa implementations */
if (this->gl_data->OSMesaDestroyLDG) {
this->gl_data->OSMesaDestroyLDG();
}
if (gl_shadow) {
Mfree(gl_shadow);
gl_shadow = NULL;
}
} else {
/* New mesa implementation */
if (gl_ctx) {
if (this->gl_data->OSMesaDestroyContext) {
this->gl_data->OSMesaDestroyContext(gl_ctx);
}
gl_ctx = NULL;
}
}
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if (unload) {
SDL_AtariGL_UnloadLibrary(this);
}
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#endif /* HAVE_OPENGL */
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gl_active = 0;
}
int SDL_AtariGL_LoadLibrary(_THIS, const char *path)
{
#ifdef HAVE_OPENGL
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#ifdef ENABLE_OSMESA_SHARED
void *handle;
if (gl_active) {
SDL_SetError("OpenGL context already created");
return -1;
}
/* Unload previous driver */
SDL_AtariGL_UnloadLibrary(this);
/* Load library given by path */
handle = SDL_LoadObject(path);
if (handle == NULL) {
/* Try to load another one */
path = getenv("SDL_VIDEO_GL_DRIVER");
if ( path != NULL ) {
handle = SDL_LoadObject(path);
}
/* If it does not work, try some other */
if (handle == NULL) {
path = PATH_OSMESA_LDG;
handle = SDL_LoadObject(path);
}
if (handle == NULL) {
path = PATH_MESAGL_LDG;
handle = SDL_LoadObject(path);
}
if (handle == NULL) {
path = PATH_TINYGL_LDG;
handle = SDL_LoadObject(path);
}
}
if (handle == NULL) {
SDL_SetError("Could not load OpenGL library");
return -1;
}
/* Load functions pointers (osmesa.ldg) */
this->gl_data->OSMesaCreateContextExt = SDL_LoadFunction(handle, "OSMesaCreateContextExt");
this->gl_data->OSMesaDestroyContext = SDL_LoadFunction(handle, "OSMesaDestroyContext");
this->gl_data->OSMesaMakeCurrent = SDL_LoadFunction(handle, "OSMesaMakeCurrent");
this->gl_data->OSMesaPixelStore = SDL_LoadFunction(handle, "OSMesaPixelStore");
this->gl_data->OSMesaGetProcAddress = SDL_LoadFunction(handle, "OSMesaGetProcAddress");
this->gl_data->glGetIntegerv = SDL_LoadFunction(handle, "glGetIntegerv");
/* Load old functions pointers (mesa_gl.ldg, tiny_gl.ldg) */
this->gl_data->OSMesaCreateLDG = SDL_LoadFunction(handle, "OSMesaCreateLDG");
this->gl_data->OSMesaDestroyLDG = SDL_LoadFunction(handle, "OSMesaDestroyLDG");
gl_oldmesa = 0;
if ( (this->gl_data->OSMesaCreateContextExt == NULL) ||
(this->gl_data->OSMesaDestroyContext == NULL) ||
(this->gl_data->OSMesaMakeCurrent == NULL) ||
(this->gl_data->OSMesaPixelStore == NULL) ||
(this->gl_data->glGetIntegerv == NULL) ||
(this->gl_data->OSMesaGetProcAddress == NULL)) {
/* Hum, maybe old library ? */
if ( (this->gl_data->OSMesaCreateLDG == NULL) ||
(this->gl_data->OSMesaDestroyLDG == NULL)) {
SDL_SetError("Could not retrieve OpenGL functions");
return -1;
} else {
gl_oldmesa = 1;
}
}
this->gl_config.dll_handle = handle;
if ( path ) {
strncpy(this->gl_config.driver_path, path,
sizeof(this->gl_config.driver_path)-1);
} else {
strcpy(this->gl_config.driver_path, "");
}
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this->gl_config.driver_loaded = 1;
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return 0;
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#else
return -1;
#endif
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}
void *SDL_AtariGL_GetProcAddress(_THIS, const char *proc)
{
void *func = NULL;
#ifdef HAVE_OPENGL
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if (this->gl_config.dll_handle) {
func = SDL_LoadFunction(this->gl_config.dll_handle, (void *)proc);
} else if (this->gl_data->OSMesaGetProcAddress) {
func = this->gl_data->OSMesaGetProcAddress(proc);
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#endif
return func;
}
int SDL_AtariGL_GetAttribute(_THIS, SDL_GLattr attrib, int* value)
{
#ifdef HAVE_OPENGL
GLenum mesa_attrib;
SDL_Surface *surface;
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if (this->gl_config.dll_handle) {
if (this->gl_data->glGetIntegerv == NULL) {
return -1;
}
}
if (!gl_active) {
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return -1;
}
switch(attrib) {
case SDL_GL_RED_SIZE:
mesa_attrib = GL_RED_BITS;
break;
case SDL_GL_GREEN_SIZE:
mesa_attrib = GL_GREEN_BITS;
break;
case SDL_GL_BLUE_SIZE:
mesa_attrib = GL_BLUE_BITS;
break;
case SDL_GL_ALPHA_SIZE:
mesa_attrib = GL_ALPHA_BITS;
break;
case SDL_GL_DOUBLEBUFFER:
surface = this->screen;
*value = ((surface->flags & SDL_DOUBLEBUF)==SDL_DOUBLEBUF);
return 0;
case SDL_GL_DEPTH_SIZE:
mesa_attrib = GL_DEPTH_BITS;
break;
case SDL_GL_STENCIL_SIZE:
mesa_attrib = GL_STENCIL_BITS;
break;
case SDL_GL_ACCUM_RED_SIZE:
mesa_attrib = GL_ACCUM_RED_BITS;
break;
case SDL_GL_ACCUM_GREEN_SIZE:
mesa_attrib = GL_ACCUM_GREEN_BITS;
break;
case SDL_GL_ACCUM_BLUE_SIZE:
mesa_attrib = GL_ACCUM_BLUE_BITS;
break;
case SDL_GL_ACCUM_ALPHA_SIZE:
mesa_attrib = GL_ACCUM_ALPHA_BITS;
break;
default :
return -1;
}
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this->gl_data->glGetIntegerv(mesa_attrib, value);
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return 0;
#else
return -1;
#endif
}
int SDL_AtariGL_MakeCurrent(_THIS)
{
#ifdef HAVE_OPENGL
SDL_Surface *surface;
GLenum type;
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if (gl_oldmesa && gl_active) {
return 0;
}
if (this->gl_config.dll_handle) {
if ((this->gl_data->OSMesaMakeCurrent == NULL) ||
(this->gl_data->OSMesaPixelStore == NULL)) {
return -1;
}
}
if (!gl_active) {
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SDL_SetError("Invalid OpenGL context");
return -1;
}
surface = this->screen;
if ((surface->format->BitsPerPixel == 15) || (surface->format->BitsPerPixel == 16)) {
type = GL_UNSIGNED_SHORT_5_6_5;
} else {
type = GL_UNSIGNED_BYTE;
}
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if (!(this->gl_data->OSMesaMakeCurrent(gl_ctx, surface->pixels, type, surface->w, surface->h))) {
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SDL_SetError("Can not make OpenGL context current");
return -1;
}
/* OSMesa draws upside down */
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this->gl_data->OSMesaPixelStore(OSMESA_Y_UP, 0);
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return 0;
#else
return -1;
#endif
}
void SDL_AtariGL_SwapBuffers(_THIS)
{
#ifdef HAVE_OPENGL
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if (gl_active) {
gl_copyshadow(this, this->screen);
gl_convert(this, this->screen);
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void SDL_AtariGL_InitPointers(_THIS)
{
#if defined(HAVE_OPENGL)
this->gl_data->OSMesaCreateContextExt = OSMesaCreateContextExt;
this->gl_data->OSMesaDestroyContext = OSMesaDestroyContext;
this->gl_data->OSMesaMakeCurrent = OSMesaMakeCurrent;
this->gl_data->OSMesaPixelStore = OSMesaPixelStore;
this->gl_data->OSMesaGetProcAddress = OSMesaGetProcAddress;
this->gl_data->glGetIntegerv = glGetIntegerv;
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#endif
}
/*--- Private functions ---*/
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static void SDL_AtariGL_UnloadLibrary(_THIS)
{
#if defined(HAVE_OPENGL)
if (this->gl_config.dll_handle) {
SDL_UnloadObject(this->gl_config.dll_handle);
this->gl_config.dll_handle = NULL;
/* Restore pointers to static library */
this->gl_data->OSMesaCreateContextExt = OSMesaCreateContextExt;
this->gl_data->OSMesaDestroyContext = OSMesaDestroyContext;
this->gl_data->OSMesaMakeCurrent = OSMesaMakeCurrent;
this->gl_data->OSMesaPixelStore = OSMesaPixelStore;
this->gl_data->OSMesaGetProcAddress = OSMesaGetProcAddress;
this->gl_data->glGetIntegerv = glGetIntegerv;
this->gl_data->OSMesaCreateLDG = NULL;
this->gl_data->OSMesaDestroyLDG = NULL;
}
#endif
}
/*--- Creation of an OpenGL context using new/old functions ---*/
static int InitNew(_THIS, SDL_Surface *current)
{
GLenum osmesa_format;
SDL_PixelFormat *pixel_format;
Uint32 redmask;
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int recreatecontext;
GLint newaccumsize;
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if (this->gl_config.dll_handle) {
if (this->gl_data->OSMesaCreateContextExt == NULL) {
return 0;
}
}
/* Init OpenGL context using OSMesa */
gl_convert = ConvertNull;
gl_copyshadow = CopyShadowNull;
pixel_format = current->format;
redmask = pixel_format->Rmask;
switch (pixel_format->BitsPerPixel) {
case 15:
/* 1555, big and little endian, unsupported */
gl_pixelsize = 2;
osmesa_format = OSMESA_RGB_565;
if (redmask == 31<<10) {
gl_convert = Convert565To555be;
} else {
gl_convert = Convert565To555le;
}
break;
case 16:
gl_pixelsize = 2;
if (redmask == 31<<11) {
osmesa_format = OSMESA_RGB_565;
} else {
/* 565, little endian, unsupported */
osmesa_format = OSMESA_RGB_565;
gl_convert = Convert565le;
}
break;
case 24:
gl_pixelsize = 3;
if (redmask == 255<<16) {
osmesa_format = OSMESA_RGB;
} else {
osmesa_format = OSMESA_BGR;
}
break;
case 32:
gl_pixelsize = 4;
if (redmask == 255<<16) {
osmesa_format = OSMESA_ARGB;
} else if (redmask == 255<<8) {
osmesa_format = OSMESA_BGRA;
} else if (redmask == 255<<24) {
osmesa_format = OSMESA_RGBA;
} else {
/* ABGR format unsupported */
osmesa_format = OSMESA_BGRA;
gl_convert = ConvertBGRAToABGR;
}
break;
default:
gl_pixelsize = 1;
osmesa_format = OSMESA_COLOR_INDEX;
break;
}
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/* Try to keep current context if possible */
newaccumsize =
this->gl_config.accum_red_size +
this->gl_config.accum_green_size +
this->gl_config.accum_blue_size +
this->gl_config.accum_alpha_size;
recreatecontext=1;
if (gl_ctx &&
(gl_curformat == osmesa_format) &&
(gl_curdepth == this->gl_config.depth_size) &&
(gl_curstencil == this->gl_config.stencil_size) &&
(gl_curaccum == newaccumsize)) {
recreatecontext = 0;
}
if (recreatecontext) {
SDL_AtariGL_Quit(this, SDL_FALSE);
gl_ctx = this->gl_data->OSMesaCreateContextExt(
osmesa_format, this->gl_config.depth_size,
this->gl_config.stencil_size, newaccumsize, NULL );
if (gl_ctx) {
gl_curformat = osmesa_format;
gl_curdepth = this->gl_config.depth_size;
gl_curstencil = this->gl_config.stencil_size;
gl_curaccum = newaccumsize;
} else {
gl_curformat = 0;
gl_curdepth = 0;
gl_curstencil = 0;
gl_curaccum = 0;
}
}
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return (gl_ctx != NULL);
}
static int InitOld(_THIS, SDL_Surface *current)
{
GLenum osmesa_format;
SDL_PixelFormat *pixel_format;
Uint32 redmask;
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int recreatecontext;
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if (this->gl_config.dll_handle) {
if (this->gl_data->OSMesaCreateLDG == NULL) {
return 0;
}
}
/* Init OpenGL context using OSMesa */
gl_convert = ConvertNull;
gl_copyshadow = CopyShadowNull;
pixel_format = current->format;
redmask = pixel_format->Rmask;
switch (pixel_format->BitsPerPixel) {
case 15:
/* 15 bits unsupported */
gl_pixelsize = 2;
osmesa_format = OSMESA_ARGB;
if (redmask == 31<<10) {
gl_copyshadow = CopyShadow8888To555;
} else {
gl_copyshadow = CopyShadow8888To565;
gl_convert = Convert565To555le;
}
break;
case 16:
/* 16 bits unsupported */
gl_pixelsize = 2;
osmesa_format = OSMESA_ARGB;
gl_copyshadow = CopyShadow8888To565;
if (redmask != 31<<11) {
/* 565, little endian, unsupported */
gl_convert = Convert565le;
}
break;
case 24:
gl_pixelsize = 3;
gl_copyshadow = CopyShadowDirect;
if (redmask == 255<<16) {
osmesa_format = OSMESA_RGB;
} else {
osmesa_format = OSMESA_BGR;
}
break;
case 32:
gl_pixelsize = 4;
gl_copyshadow = CopyShadowDirect;
if (redmask == 255<<16) {
osmesa_format = OSMESA_ARGB;
} else if (redmask == 255<<8) {
osmesa_format = OSMESA_BGRA;
} else if (redmask == 255<<24) {
osmesa_format = OSMESA_RGBA;
} else {
/* ABGR format unsupported */
osmesa_format = OSMESA_BGRA;
gl_convert = ConvertBGRAToABGR;
}
break;
default:
gl_pixelsize = 1;
gl_copyshadow = CopyShadowDirect;
osmesa_format = OSMESA_COLOR_INDEX;
break;
}
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/* Try to keep current context if possible */
recreatecontext=1;
if (gl_shadow &&
(gl_curformat == osmesa_format) &&
(gl_curwidth == current->w) &&
(gl_curheight == current->h)) {
recreatecontext = 0;
}
if (recreatecontext) {
SDL_AtariGL_Quit(this, SDL_FALSE);
gl_shadow = this->gl_data->OSMesaCreateLDG(
osmesa_format, GL_UNSIGNED_BYTE, current->w, current->h
);
if (gl_shadow) {
gl_curformat = osmesa_format;
gl_curwidth = current->w;
gl_curheight = current->h;
} else {
gl_curformat = 0;
gl_curwidth = 0;
gl_curheight = 0;
}
}
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return (gl_shadow != NULL);
}
/*--- Conversions routines from shadow buffer to the screen ---*/
static void CopyShadowNull(_THIS, SDL_Surface *surface)
{
}
static void CopyShadowDirect(_THIS, SDL_Surface *surface)
{
int y, srcpitch, dstpitch;
Uint8 *srcline, *dstline;
srcline = gl_shadow;
srcpitch = surface->w * gl_pixelsize;
dstline = surface->pixels;
dstpitch = surface->pitch;
for (y=0; y<surface->h; y++) {
memcpy(dstline, srcline, srcpitch);
srcline += srcpitch;
dstline += dstpitch;
}
}
static void CopyShadow8888To555(_THIS, SDL_Surface *surface)
{
int x,y, srcpitch, dstpitch;
Uint16 *dstline, *dstcol;
Uint32 *srcline, *srccol;
srcline = (Uint32 *)gl_shadow;
srcpitch = surface->w;
dstline = surface->pixels;
dstpitch = surface->pitch >>1;
for (y=0; y<surface->h; y++) {
srccol = srcline;
dstcol = dstline;
for (x=0; x<surface->w; x++) {
Uint32 srccolor;
Uint16 dstcolor;
srccolor = *srccol++;
dstcolor = (srccolor>>9) & (31<<10);
dstcolor |= (srccolor>>6) & (31<<5);
dstcolor |= (srccolor>>3) & 31;
*dstcol++ = dstcolor;
}
srcline += srcpitch;
dstline += dstpitch;
}
}
static void CopyShadow8888To565(_THIS, SDL_Surface *surface)
{
int x,y, srcpitch, dstpitch;
Uint16 *dstline, *dstcol;
Uint32 *srcline, *srccol;
srcline = (Uint32 *)gl_shadow;
srcpitch = surface->w;
dstline = surface->pixels;
dstpitch = surface->pitch >>1;
for (y=0; y<surface->h; y++) {
srccol = srcline;
dstcol = dstline;
for (x=0; x<surface->w; x++) {
Uint32 srccolor;
Uint16 dstcolor;
srccolor = *srccol++;
dstcolor = (srccolor>>8) & (31<<11);
dstcolor |= (srccolor>>5) & (63<<5);
dstcolor |= (srccolor>>3) & 31;
*dstcol++ = dstcolor;
}
srcline += srcpitch;
dstline += dstpitch;
}
}
/*--- Conversions routines in the screen ---*/
static void ConvertNull(_THIS, SDL_Surface *surface)
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static void Convert565To555be(_THIS, SDL_Surface *surface)
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{
int x,y, pitch;
unsigned short *line, *pixel;
line = surface->pixels;
pitch = surface->pitch >> 1;
for (y=0; y<surface->h; y++) {
pixel = line;
for (x=0; x<surface->w; x++) {
unsigned short color = *pixel;
*pixel++ = (color & 0x1f)|((color>>1) & 0xffe0);
}
line += pitch;
}
}
691
static void Convert565To555le(_THIS, SDL_Surface *surface)
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{
int x,y, pitch;
unsigned short *line, *pixel;
line = surface->pixels;
pitch = surface->pitch >>1;
for (y=0; y<surface->h; y++) {
pixel = line;
for (x=0; x<surface->w; x++) {
unsigned short color = *pixel;
color = (color & 0x1f)|((color>>1) & 0xffe0);
*pixel++ = SDL_Swap16(color);
}
line += pitch;
}
}
711
static void Convert565le(_THIS, SDL_Surface *surface)
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{
int x,y, pitch;
unsigned short *line, *pixel;
line = surface->pixels;
pitch = surface->pitch >>1;
for (y=0; y<surface->h; y++) {
pixel = line;
for (x=0; x<surface->w; x++) {
unsigned short color = *pixel;
*pixel++ = SDL_Swap16(color);
}
line += pitch;
}
}
730
static void ConvertBGRAToABGR(_THIS, SDL_Surface *surface)
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{
int x,y, pitch;
unsigned long *line, *pixel;
line = surface->pixels;
pitch = surface->pitch >>2;
for (y=0; y<surface->h; y++) {
pixel = line;
for (x=0; x<surface->w; x++) {
unsigned long color = *pixel;
*pixel++ = (color<<24)|(color>>8);
}
line += pitch;
}
}