mirror of
https://github.com/kovidgoyal/kitty
synced 2026-07-16 21:45:03 +02:00
d52f2e7981
This was needed to fix various corner cases when doing blending of colors in linear space. The new architecture has the same performance as the old in the common case of opaque rendering with no UI layers or images. In the case of only positive z-index images there is a performance decrease as the OS Window is now rendered to a offscreen texture and then blitted to screen. However, in the future when we move to Vulkan or I can figure out how to get Wayland to accept buffers with colors in linear space, this performance penalty can be removed. The performance penalty was not significant on my system but this is highly GPU dependent. Modern GPUs are supposedly optimised for rendering to offscreen buffers, so we will see. The awrit project might be a good test case. Now either we have 1-shot rendering for the case of opaque with only ext or all the various pieces are rendered in successive draw calls into an offscreen buffer that is blitted to the output buffer after all drawing is done. Fixes #8869
30 lines
632 B
GLSL
30 lines
632 B
GLSL
#pragma kitty_include_shader <alpha_blend.glsl>
|
|
#pragma kitty_include_shader <utils.glsl>
|
|
#define ALPHA_TYPE
|
|
|
|
uniform sampler2D image;
|
|
#ifdef ALPHA_MASK
|
|
uniform vec3 amask_fg;
|
|
uniform vec4 amask_bg_premult;
|
|
#else
|
|
uniform float extra_alpha;
|
|
#endif
|
|
|
|
in vec2 texcoord;
|
|
out vec4 output_color;
|
|
|
|
void main() {
|
|
vec4 color = texture(image, texcoord);
|
|
#ifdef ALPHA_MASK
|
|
color = vec4(amask_fg, color.r);
|
|
color = vec4_premul(color);
|
|
color = alpha_blend_premul(color, amask_bg_premult);
|
|
#else
|
|
color.a *= extra_alpha;
|
|
#if TEXTURE_IS_NOT_PREMULTIPLIED
|
|
color = vec4_premul(color);
|
|
#endif
|
|
#endif
|
|
output_color = color;
|
|
}
|