./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
Sylvain
Re-opening this issue.
It fixes the test-case, but it introduces a regression with another bug (bug #4313).
So here's a new patch that activate cropping of the source surface to solve the issue.
It also reverts the wrong changeset.
It prevents unneeded colorkey error message.
Olli-Samuli Lehmus
If one creates a window with the SDL_WINDOW_FULLSCREEN_DESKTOP flag, and creates a render target with SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "linear"), and afterwards sets SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "nearest"), after minimizing the window, the scale quality hint is lost on the render target. Textures however do keep their interpolation modes.
Daniel
SDL_RenderReadPixels with SDL_RENDERER_SOFTWARE reads pixels from wrong coordinates.
SW_RenderReadPixels adjusts the rect coordinates according to the viewport. But since this is already done by SDL_RenderReadPixels, the final rect has x2 bigger X and Y.
Simon Hug
The software renderer produces incorrect results when blending textures at an angle with certain blend modes. It seems that there were some edge cases that weren't considered when the SW_RenderCopyEx function was last changed. Or another bug possibly covered up the problem. (More on that in another bug report.)
Most of the issues come from the fact that the rotating function sets a black colorkey. This is problematic because black is most likely appearing in the surface and the final blit will ignore these pixels. Unless a colorkey is already set (the software renderer currently never sets one), it's very hard to find a free color. Of course it could scan over the whole image until one is found, but that seems inefficient.
The following blend modes have issues when drawn at an angle.
NONE: The black pixels get ignored, making them essentially transparent. This breaks the 'dstRGBA = srcRGBA' definition of the NONE blend mode.
MOD: Again, the black pixels get ignored. This also breaks the 'dstRGB = dstRGB * srcRGB' definition of the MOD blend mode, where black pixels would make the destination black as well. A white colorkey will work though, with some preparations.
BLEND: There are some issues when blending a texture with a translucent RGBA target texture. I - uh - forgot what the problem here exactly is.
This patch fixes the issues mentioned above. It mainly changes the code so it tries to do things without the colorkey and removes the automatic format conversion part from the SDLgfx_rotateSurface function. Getting the format right is something the caller has to do now and the required code has been added to the SW_RenderCopyEx function.
There's a small change to the SW_CreateTexture function. RLE encoding a surface with an alpha mask can be a lossy process. Depending on how the user uses the RGBA channels, this may be undesired. The change that surfaces with an alpha mask don't get encoded makes the software renderer consistent with the other renderers.
The SW_RenderCopyEx function now does these steps: Lock the source surface if necessary. Create a clone of the source by using the pixel buffer directly. Check the format and set a flag if a conversion is necessary. Check if scaling or cropping is necessary and set the flag for that as well. Check if color and alpha modulation has to be done before the rotate. Check if the source is an opaque surface. If not, it creates a mask surface that is necessary for the NONE blend mode. If any of the flags were set, a new surface is created and the source will be converted, scaled, cropped, and modulated. The rest of the function stays somewhat the same. The mask also needs to be rotated of course and then there is the NONE blend mode...
It's surprisingly hard to get the pixel from a rotated surface to the destination buffer without affecting the pixel outside the rotated area. I found a way to do this with three blits which is pretty hard on the performance. Perhaps someone has an idea how to do this faster?
As mentioned above, the SDLgfx_rotateSurface now only takes 8-bit paletted or 32-bit with alpha mask surfaces. It additionally sets the new surfaces up for the MOD blend mode.
I shortly tested the 8-bit path of SDLgfx_rotateSurface and it seemed to work so far. This path is not used by the software renderer anyway.
Adam M.
When doing a rotated texture copy with the software renderer, where the angle is a multiple of 90 degrees, one or two edges of the image get cut off. This is because of the following line in sw_rotate.c:
if ((unsigned)dx < (unsigned)sw && (unsigned)dy < (unsigned)sh) {
which is effectively saying:
if (dx >= 0 && dx < src->w-1 && dy >= 0 && dy < src->h-1) {
As a result, it doesn't process pixels in the right column or bottom row of the source image (except when they're accessed as part of the bilinear filtering for nearby pixels). This causes it to look like the edges are cut off, and it's especially obvious with an exact multiple of 90 degrees.
Adam M.
There are three problems in the code that I see.
1. SW_RenderCopyEx enables a color key on surface_scaled even if the source surface didn't have a color key.
2. SW_RenderCopyEx doesn't copy blend mode, color mod, or alpha mod from src to surface_scaled.
3. When SDL_BlitScaled(src, srcrect, surface_scaled, &tmp_rect) is called, it blends the src pixels into surface_scaled instead of overwriting them (if src has blending, etc. enabled).
I've attached a patch that 1) fixes the three problems that I mentioned, 2) adds the requested performance improvement of using the regular blit function if no rotation or flipping is needed, 3) avoids cloning the source surface if no stretching is required, and simplifies the rotation code slightly.
Damian Kaczmarek
Basically this bug is probably not a common use case. My goal is to allow rendering totally without a window, for example to a screenshot and I need to rely on SDL_SetRenderTarget to properly work for a purely software renderer created by SDL_CreateSoftwareRenderer.
This fixes an issue where an empty cliprect is treated the same as a NULL
cliprect, causing the render backends to disable clipping.
Also adds a new API, SDL_RenderIsClipEnabled(render) that allows you to
differentiate between:
- SDL_RenderSetClipRect(render, NULL)
- SDL_Rect r = {0,0,0,0}; SDL_RenderSetClipRect(render, &r);
Fixes https://bugzilla.libsdl.org/show_bug.cgi?id=2504
This lets us change things like this...
if (Failed) {
SDL_SetError("We failed");
return -1;
}
...into this...
if (Failed) {
return SDL_SetError("We failed");
}
Fixes Bugzilla #1778.
Dimitris Zenios Date: 2012-02-06 15:12:37 GMT
Hi gus there is a bug when using software renderer and the window
surface gets destroyed (Fullscreen and back).The solution is easy
The render viewport is automatically re-centered when the window changes size, so applications that don't care will not have to handle recalculating their rendering coordinates.
Fixed API for drawing and filling multiple rectangles - the parameter should be an array of rects, not an array of pointers to rects.
Fixed API for updating window rects for consistency with other APIs - the order is pointer to array followed by count in array.
