1 files changed, 58 insertions, 0 deletions
diff --git a/config/picom/shaders/terminal_vignette.glsl b/config/picom/shaders/terminal_vignette.glsl
new file mode 100644
index 0000000..4e5aa21
--- /dev/null
+++ b/config/picom/shaders/terminal_vignette.glsl
@@ -0,0 +1,58 @@
+#version 330
+in vec2 texcoord;             // texture coordinate of the fragment
+
+uniform sampler2D tex;        // texture of the window
+
+ivec2 window_size = textureSize(tex, 0); // Size of the window
+ivec2 window_center = ivec2(window_size.x/2, window_size.y/2);
+uniform float shadow_cutoff = 1; // How "early" the shadow starts affecting 
+                                 // pixels close to the edges
+                                 // I'd keep this value very close to 1
+uniform int shadow_intensity = 3; // Intensity level of the shadow effect (from 1 to 5)
+
+
+// Default window post-processing:
+// 1) invert color
+// 2) opacity / transparency
+// 3) max-brightness clamping
+// 4) rounded corners
+vec4 default_post_processing(vec4 c);
+
+// Darkens a pixels near the edges
+vec4 calc_opacity(vec4 color, vec2 coords)
+{
+    // If shadow intensity is 0, change nothing
+    if (shadow_intensity == 0)
+    {
+        return color;
+    }
+
+    // Get how far the coords are from the center
+    vec2 distances_from_center = abs(window_center - coords);
+
+    // Darken pixels close to the edges of the screen in a polynomial fashion
+    float opacity = 1;
+    opacity *= -pow((distances_from_center.y/window_center.y)*shadow_cutoff, 
+                       (5/shadow_intensity)*2)+1;
+    opacity *= -pow((distances_from_center.x/window_center.x)*shadow_cutoff, 
+                       (5/shadow_intensity)*2)+1;
+    color.w *= opacity;
+    color.w = max(1 - color.w, 0.8);
+
+    return color;
+}
+
+
+// Default window shader:
+// 1) fetch the specified pixel
+// 2) apply default post-processing
+vec4 window_shader() {
+    vec4 c = texelFetch(tex, ivec2(texcoord), 0);
+    if (c.x +c.y + c.z < 0.6)
+    {
+        c.w = 1;
+        c = calc_opacity(c,texcoord);
+    }
+
+    return default_post_processing(c);
+}