Better Blur

Not required in 24w11a and above!

Note: This resource pack requires a full game restart to load correctly. A restart is also required after disabling the pack.

Improves the blur algorithm used in 24w09a's new GUI.

The vanilla blur algorithm uses an unweighted average of surrounding pixels, which produces a blocky appearance (especially look around the hotbar):

This resource pack slightly modifies the algorithm to reduce the weight of further away pixels, which produces a much nicer blur effect:

This is the entire patch to the vanilla blur shader:

--- vanilla/assets/minecraft/shaders/program/blur.fsh    2024-02-28 12:37:42.000000000 +0000
+++ betterblur/assets/minecraft/shaders/program/blur.fsh    2024-02-28 18:44:39.232389841 +0000
@@ -28,7 +28,7 @@
         // Accumulate smoothed blur
         float strength = 1.0 - abs(r / Radius);
         totalStrength = totalStrength + strength;
-        blurred = blurred + sampleValue;
+        blurred = blurred + (sampleValue * strength);
     }
-    fragColor = vec4(blurred.rgb / (Radius * 2.0 + 1.0), totalAlpha);
+    fragColor = vec4(blurred.rgb / totalStrength, totalAlpha);
 }

Given the strength and totalStrength variables are already in the vanilla shader but are unused, it seems possible that the blur algorithm was originally intended to be more similar to this resource pack.

I release this under CC0 1.0 Universal, although it probably isn't substantial enough to be eligible for copyright anyway.