Sylvain
Currently SDL_CreateTextureFromSurface picks first valid format, and do a conversion.
format = renderer->info.texture_formats[0];
for (i = 0; i < renderer->info.num_texture_formats; ++i) {
if (!SDL_ISPIXELFORMAT_FOURCC(renderer->info.texture_formats[i]) &&
SDL_ISPIXELFORMAT_ALPHA(renderer->info.texture_formats[i]) == needAlpha) {
format = renderer->info.texture_formats[i];
break;
It could try to find a better format, for instance :
if SDL_Surface has no Amask, but a colorkey :
if surface fmt is RGB888, try to pick ARGB8888 renderer fmt
if surface fmt is BGR888, try to pick ABGR8888 renderer fmt
else
try to pick the same renderer format as surface fmt
if no format has been picked, use the fallback.
I think it goes with bug 4290 fastpath BlitNtoN
when you expand a surface with pixel format of size 24 to 32, there is a fast path possible.
So with this issue:
- if you have a surface with colorkey (RGB or BGR, not palette), it takes a renderer format where the conversion is faster.
(it avoids, if possible, RGB -> ABGR which means switching RGB to BGR)
- if you have a surface ABGR format, it try to take the ABGR from the renderer.
(it avoids, if possible, ABGR -> ARGB, which means switch RGB to BGR)
Sylvain
OpenGLES2 SDL renderer has support for textures ARGB, ABGR, RGB and BGR, whereas OpenGL SDL renderer only had ARGB.
If you think it's worth adding it, here's a patch. I quickly tried and it worked, but there may be missing things or corner case.
This is the best option for macOS and iOS, the only platforms with Metal.
Pre-Metal versions of these platforms will fall back to OpenGL (ES), as
appropriate.
Huge thanks to Alexander Szpakowski, who worked incredibly hard to get the
Metal renderer to such a high-quality state!
./src/render/SDL_render.c(2168): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2168): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2175): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2175): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2322): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2322): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2322): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2322): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2329): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2329): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2329): Error! E1054: Expression must be constant
./src/render/SDL_render.c(2329): Error! E1054: Expression must be constant
./src/render/software/SDL_render_sw.c(602): Error! E1054: Expression must be constant
./src/render/software/SDL_render_sw.c(602): Error! E1054: Expression must be constant
./src/render/software/SDL_render_sw.c(602): Error! E1054: Expression must be constant
./src/render/software/SDL_render_sw.c(602): Error! E1054: Expression must be constant
https://bugzilla.libsdl.org/show_bug.cgi?id=4350
We can't safely call GL_DestroyRenderer() until GL_LoadFunctions()
succeeds because we will be missing functions that we try to use
when activating the renderer for destruction if we have an GL context.
