refactor: make the whole thing more generic

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

@@ -0,0 +1,24 @@
+// vim: set ft=glsl:
+
+precision highp float;
+varying highp vec2 v_texcoord;
+uniform highp sampler2D tex;
+
+#define STRENGTH 0.0027
+
+void main() {
+    vec2 center = vec2(0.5, 0.5);
+    vec2 offset = (v_texcoord - center) * STRENGTH;
+
+    float rSquared = dot(offset, offset);
+    float distortion = 1.0 + 1.0 * rSquared;
+    vec2 distortedOffset = offset * distortion;
+
+    vec2 redOffset = vec2(distortedOffset.x, distortedOffset.y);
+    vec2 blueOffset = vec2(distortedOffset.x, distortedOffset.y);
+
+    vec4 redColor = texture2D(tex, v_texcoord + redOffset);
+    vec4 blueColor = texture2D(tex, v_texcoord + blueOffset);
+
+    gl_FragColor = vec4(redColor.r, texture2D(tex, v_texcoord).g, blueColor.b, 1.0);
+}