From a6b47be34f8e00f5efb9b7530c9e2bd5d16e6f56 Mon Sep 17 00:00:00 2001
From: Simon Schneegans <code@simonschneegans.de>
Date: Mon, 14 Aug 2023 05:58:03 +0200
Subject: [PATCH] :beetle: Prevent GLSL from optimizing our uniforms on KWin

---
 resources/shaders/common.glsl | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/resources/shaders/common.glsl b/resources/shaders/common.glsl
index 988dbf3..cacdf4c 100644
--- a/resources/shaders/common.glsl
+++ b/resources/shaders/common.glsl
@@ -64,6 +64,15 @@ vec4 getInputColor(vec2 coords) {
 }
 
 void setOutputColor(vec4 outColor) {
+
+  // If a uniform is not used, it will be optimized away. This condition is always
+  // false, but it will prevent the compiler from optimizing away the uniforms uForOpening
+  // and uIsFullscreen. On KWin, we need to do this as we do not have a way to check if a
+  // uniform is used in the shader.
+  if (outColor.a > 10e42 && uForOpening && uIsFullscreen) {
+    outColor = vec4(0.0);
+  }
+
   fragColor = vec4(outColor.rgb * outColor.a, outColor.a);
 }
 
@@ -90,6 +99,14 @@ vec4 getInputColor(vec2 coords) {
 }
 
 void setOutputColor(vec4 outColor) {
+  // If a uniform is not used, it will be optimized away. This condition is always
+  // false, but it will prevent the compiler from optimizing away the uniforms uForOpening
+  // and uIsFullscreen. On KWin, we need to do this as we do not have a way to check if a
+  // uniform is used in the shader.
+  if (outColor.a > 10e42 && uForOpening && uIsFullscreen) {
+    outColor = vec4(0.0);
+  }
+
   gl_FragColor = vec4(outColor.rgb * outColor.a, outColor.a);
 }