refactor: make the whole thing more generic

modules/home-manager/desktops/hyprland/hypr/shaders/blur.frag

@@ -0,0 +1,39 @@
+precision mediump float;
+varying vec2 v_texcoord; // is in 0-1
+uniform sampler2D tex;
+uniform float alpha;
+
+uniform vec2 topLeft;
+uniform vec2 fullSize;
+uniform float radius;
+
+uniform int discardOpaque;
+uniform int discardAlpha;
+uniform float discardAlphaValue;
+
+uniform int applyTint;
+uniform vec3 tint;
+
+uniform int primitiveMultisample;
+
+void main() {
+
+    vec4 pixColor = texture2D(tex, v_texcoord);
+
+    if (discardOpaque == 1 && pixColor[3] * alpha == 1.0)
+	    discard;
+    
+    if (discardAlpha == 1 && pixColor[3] <= discardAlphaValue)
+        discard;
+
+    if (applyTint == 1) {
+	    pixColor[0] = pixColor[0] * tint[0];
+	    pixColor[1] = pixColor[1] * tint[1];
+	    pixColor[2] = pixColor[2] * tint[2];
+    }
+
+    )#" +
+    ROUNDED_SHADER_FUNC("pixColor") + R"#(
+
+    gl_FragColor = pixColor * alpha;
+}