You can specify the format for pixel data in SDL_RenderReadPixels() and SDL_RenderWritePixels()
This code still doesn't quite work yet. :)
--- a/include/SDL_video.h Sun Nov 15 09:21:46 2009 +0000
+++ b/include/SDL_video.h Mon Nov 16 07:13:07 2009 +0000
@@ -1173,8 +1173,9 @@
*
* \param rect A pointer to the rectangle to read, or NULL for the entire
* render target.
- * \param pixels A pointer to be filled in with the pixel data in the rendering
- * target format.
+ * \param format The desired format of the pixel data, or 0 to use the format
+ * of the rendering target
+ * \param pixels A pointer to be filled in with the pixel data
* \param pitch The pitch of the pixels parameter.
*
* \return 0 on success, or -1 if pixel reading is not supported.
@@ -1182,6 +1183,7 @@
* \warning This is a very slow operation, and should not be used frequently.
*/
extern DECLSPEC int SDLCALL SDL_RenderReadPixels(const SDL_Rect * rect,
+ Uint32 format,
void *pixels, int pitch);
/**
@@ -1189,6 +1191,8 @@
*
* \param rect A pointer to the rectangle to write, or NULL for the entire
* render target.
+ * \param format The format of the pixel data, or 0 to use the format
+ * of the rendering target
* \param pixels A pointer to the pixel data to write.
* \param pitch The pitch of the pixels parameter.
*
@@ -1197,6 +1201,7 @@
* \warning This is a very slow operation, and should not be used frequently.
*/
extern DECLSPEC int SDLCALL SDL_RenderWritePixels(const SDL_Rect * rect,
+ Uint32 format,
const void *pixels,
int pitch);
--- a/src/video/SDL_renderer_gl.c Sun Nov 15 09:21:46 2009 +0000
+++ b/src/video/SDL_renderer_gl.c Mon Nov 16 07:13:07 2009 +0000
@@ -103,9 +103,9 @@
static int GL_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
const SDL_Rect * srcrect, const SDL_Rect * dstrect);
static int GL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- void * pixels, int pitch);
+ Uint32 pixel_format, void * pixels, int pitch);
static int GL_RenderWritePixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- const void * pixels, int pitch);
+ Uint32 pixel_format, const void * pixels, int pitch);
static void GL_RenderPresent(SDL_Renderer * renderer);
static void GL_DestroyTexture(SDL_Renderer * renderer, SDL_Texture * texture);
static void GL_DestroyRenderer(SDL_Renderer * renderer);
@@ -1254,16 +1254,16 @@
static int
GL_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- void * pixels, int pitch)
+ Uint32 pixel_format, void * pixels, int pitch)
{
GL_RenderData *data = (GL_RenderData *) renderer->driverdata;
- SDL_Window *window = SDL_GetWindowFromID(renderer->window);
- SDL_VideoDisplay *display = SDL_GetDisplayFromWindow(window);
- Uint32 pixel_format = display->current_mode.format;
GLint internalFormat;
GLenum format, type;
+ Uint8 *src, *dst, *tmp;
+ int length, rows;
if (!convert_format(data, pixel_format, &internalFormat, &format, &type)) {
+ /* FIXME: Do a temp copy to a format that is supported */
SDL_SetError("Unsupported pixel format");
return -1;
}
@@ -1275,16 +1275,52 @@
}
data->glPixelStorei(GL_PACK_ALIGNMENT, 1);
data->glPixelStorei(GL_PACK_ROW_LENGTH,
- -2 * (pitch / bytes_per_pixel(pixel_format)));
+ (pitch / bytes_per_pixel(pixel_format)));
data->glReadPixels(rect->x, rect->y+rect->h-1, rect->w, rect->h,
- format, type, pixels + (rect->h-1)*pitch);
+ format, type, pixels);
+
+ /* Flip the rows to be top-down */
+ length = rect->w * bytes_per_pixel(pixel_format);
+ src = (Uint8*)pixels + (rect->h-1)*pitch;
+ dst = (Uint8*)pixels;
+ tmp = SDL_stack_alloc(Uint8, length);
+ rows = rect->h / 2;
+ while (rows--) {
+ SDL_memcpy(tmp, dst, length);
+ SDL_memcpy(dst, src, length);
+ SDL_memcpy(src, tmp, length);
+ }
+ SDL_stack_free(tmp);
}
static int
GL_RenderWritePixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- const void * pixels, int pitch)
+ Uint32 pixel_format, const void * pixels, int pitch)
{
+ GL_RenderData *data = (GL_RenderData *) renderer->driverdata;
+ GLint internalFormat;
+ GLenum format, type;
+
+ if (!convert_format(data, pixel_format, &internalFormat, &format, &type)) {
+ /* FIXME: Do a temp copy to a format that is supported */
+ SDL_SetError("Unsupported pixel format");
+ return -1;
+ }
+
+ /* FIXME: We need to copy the data and flip it */
+
+ if (pixel_format == SDL_PIXELFORMAT_INDEX1LSB) {
+ data->glPixelStorei(GL_UNPACK_LSB_FIRST, 1);
+ } else if (pixel_format == SDL_PIXELFORMAT_INDEX1MSB) {
+ data->glPixelStorei(GL_UNPACK_LSB_FIRST, 0);
+ }
+ data->glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ data->glPixelStorei(GL_UNPACK_ROW_LENGTH,
+ (pitch / bytes_per_pixel(pixel_format)));
+
+ data->glReadPixels(rect->x, rect->y+rect->h-1, rect->w, rect->h,
+ format, type, pixels);
}
static void
--- a/src/video/SDL_renderer_sw.c Sun Nov 15 09:21:46 2009 +0000
+++ b/src/video/SDL_renderer_sw.c Mon Nov 16 07:13:07 2009 +0000
@@ -66,9 +66,9 @@
static int SW_RenderCopy(SDL_Renderer * renderer, SDL_Texture * texture,
const SDL_Rect * srcrect, const SDL_Rect * dstrect);
static int SW_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- void * pixels, int pitch);
+ Uint32 format, void * pixels, int pitch);
static int SW_RenderWritePixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- const void * pixels, int pitch);
+ Uint32 format, const void * pixels, int pitch);
static void SW_RenderPresent(SDL_Renderer * renderer);
static void SW_DestroyTexture(SDL_Renderer * renderer, SDL_Texture * texture);
static void SW_DestroyRenderer(SDL_Renderer * renderer);
@@ -736,12 +736,9 @@
static int
SW_RenderReadPixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- void * pixels, int pitch)
+ Uint32 format, void * pixels, int pitch)
{
SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
- const Uint8 *src;
- Uint8 *dst;
- int src_pitch, dst_pitch, w, h;
if (data->renderer->LockTexture(data->renderer,
data->texture[data->current_texture],
@@ -750,17 +747,9 @@
return -1;
}
- src = data->surface.pixels;
- src_pitch = data->surface.pitch;
- dst = pixels;
- dst_pitch = pitch;
- h = rect->h;
- w = rect->w * data->surface.format->BytesPerPixel;
- while (h--) {
- SDL_memcpy(dst, src, w);
- src += src_pitch;
- dst += dst_pitch;
- }
+ SDL_ConvertPixels(rect->w, rect->h,
+ data->format, data->surface.pixels, data->surface.pitch,
+ format, pixels, pitch);
data->renderer->UnlockTexture(data->renderer,
data->texture[data->current_texture]);
@@ -769,12 +758,9 @@
static int
SW_RenderWritePixels(SDL_Renderer * renderer, const SDL_Rect * rect,
- const void * pixels, int pitch)
+ Uint32 format, const void * pixels, int pitch)
{
SW_RenderData *data = (SW_RenderData *) renderer->driverdata;
- const Uint8 *src;
- Uint8 *dst;
- int src_pitch, dst_pitch, w, h;
if (data->renderer->info.flags & SDL_RENDERER_PRESENTCOPY) {
SDL_AddDirtyRect(&data->dirty, rect);
@@ -787,17 +773,8 @@
return -1;
}
- src = pixels;
- src_pitch = pitch;
- dst = data->surface.pixels;
- dst_pitch = data->surface.pitch;
- h = rect->h;
- w = rect->w * data->surface.format->BytesPerPixel;
- while (h--) {
- SDL_memcpy(dst, src, w);
- src += src_pitch;
- dst += dst_pitch;
- }
+ SDL_ConvertPixels(rect->w, rect->h, format, pixels, pitch,
+ data->format, data->surface.pixels, data->surface.pitch);
data->renderer->UnlockTexture(data->renderer,
data->texture[data->current_texture]);
--- a/src/video/SDL_sysvideo.h Sun Nov 15 09:21:46 2009 +0000
+++ b/src/video/SDL_sysvideo.h Mon Nov 16 07:13:07 2009 +0000
@@ -97,9 +97,9 @@
int (*RenderCopy) (SDL_Renderer * renderer, SDL_Texture * texture,
const SDL_Rect * srcrect, const SDL_Rect * dstrect);
int (*RenderReadPixels) (SDL_Renderer * renderer, const SDL_Rect * rect,
- void * pixels, int pitch);
+ Uint32 format, void * pixels, int pitch);
int (*RenderWritePixels) (SDL_Renderer * renderer, const SDL_Rect * rect,
- const void * pixels, int pitch);
+ Uint32 format, const void * pixels, int pitch);
void (*RenderPresent) (SDL_Renderer * renderer);
void (*DestroyTexture) (SDL_Renderer * renderer, SDL_Texture * texture);
--- a/src/video/SDL_video.c Sun Nov 15 09:21:46 2009 +0000
+++ b/src/video/SDL_video.c Mon Nov 16 07:13:07 2009 +0000
@@ -2487,7 +2487,8 @@
}
int
-SDL_RenderReadPixels(const SDL_Rect * rect, void * pixels, int pitch)
+SDL_RenderReadPixels(const SDL_Rect * rect, Uint32 format,
+ void * pixels, int pitch)
{
SDL_Renderer *renderer;
SDL_Window *window;
@@ -2503,6 +2504,10 @@
}
window = SDL_GetWindowFromID(renderer->window);
+ if (!format) {
+ format = SDL_GetDisplayFromWindow(window)->current_mode.format;
+ }
+
real_rect.x = 0;
real_rect.y = 0;
real_rect.w = window->w;
@@ -2521,11 +2526,13 @@
}
}
- return renderer->RenderReadPixels(renderer, &real_rect, pixels, pitch);
+ return renderer->RenderReadPixels(renderer, &real_rect,
+ format, pixels, pitch);
}
int
-SDL_RenderWritePixels(const SDL_Rect * rect, const void * pixels, int pitch)
+SDL_RenderWritePixels(const SDL_Rect * rect, Uint32 format,
+ const void * pixels, int pitch)
{
SDL_Renderer *renderer;
SDL_Window *window;
@@ -2541,6 +2548,10 @@
}
window = SDL_GetWindowFromID(renderer->window);
+ if (!format) {
+ format = SDL_GetDisplayFromWindow(window)->current_mode.format;
+ }
+
real_rect.x = 0;
real_rect.y = 0;
real_rect.w = window->w;
@@ -2559,7 +2570,8 @@
}
}
- return renderer->RenderWritePixels(renderer, &real_rect, pixels, pitch);
+ return renderer->RenderWritePixels(renderer, &real_rect,
+ format, pixels, pitch);
}
void
--- a/test/automated/common/common.h Sun Nov 15 09:21:46 2009 +0000
+++ b/test/automated/common/common.h Mon Nov 16 07:13:07 2009 +0000
@@ -12,11 +12,13 @@
#if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
+# define FORMAT SDL_PIXELFORMAT_RGBA8888
# define RMASK 0xff000000 /**< Red bit mask. */
# define GMASK 0x00ff0000 /**< Green bit mask. */
# define BMASK 0x0000ff00 /**< Blue bit mask. */
# define AMASK 0x000000ff /**< Alpha bit mask. */
#else
+# define FORMAT SDL_PIXELFORMAT_ABGR8888
# define RMASK 0x000000ff /**< Red bit mask. */
# define GMASK 0x0000ff00 /**< Green bit mask. */
# define BMASK 0x00ff0000 /**< Blue bit mask. */
--- a/test/automated/render/render.c Sun Nov 15 09:21:46 2009 +0000
+++ b/test/automated/render/render.c Mon Nov 16 07:13:07 2009 +0000
@@ -67,7 +67,7 @@
return 1;
/* Read pixels. */
- ret = SDL_RenderReadPixels( NULL, pix, 80*4 );
+ ret = SDL_RenderReadPixels( NULL, FORMAT, pix, 80*4 );
if (SDL_ATassert( "SDL_RenderReadPixels", ret==0) )
return 1;