Add grayscale filter

.config/hypr/hyprland.conf

@@ -69,6 +69,8 @@ general {
 decoration {
     # See https://wiki.hyprland.org/Configuring/Variables/ for more
 
+		screen_shader = /home/daniele/.config/hypr/shaders/grayscale.frag
+
     rounding = 5
     
     blur {

.config/hypr/shaders/grayscale.frag

@@ -0,0 +1,33 @@
+//
+// Example blue light filter shader.
+// 
+
+//precision mediump float;
+//varying vec2 v_texcoord;
+//uniform sampler2D tex;
+//
+//void main() {
+//
+//    vec4 pixColor = texture2D(tex, v_texcoord);
+//
+//    pixColor[2] *= 0.;
+//
+//    gl_FragColor = pixColor;
+//}
+// Example grayscale shader.
+
+precision mediump float; // Set the precision for floating-point calculations.
+varying vec2 v_texcoord; // Varying texture coordinate passed from the vertex shader.
+uniform sampler2D tex;   // The texture sampler.
+
+void main() {
+    // Sample the texture at the given coordinates.
+    vec4 pixColor = texture2D(tex, v_texcoord);
+
+    // Compute the grayscale value using standard luminance weights.
+    float gray = 0.299 * pixColor.r + 0.587 * pixColor.g + 0.114 * pixColor.b;
+
+    // Set the fragment color to the grayscale value, keeping the original alpha.
+    gl_FragColor = vec4(vec3(gray), pixColor.a);
+}
+