fixed the issue with alpha blending - fixing blur remaining

Author: Piyushrathoree

src/core/filterShaders.js

@@ -102,11 +102,21 @@ export function makeFilterShader(renderer, operation, p5) {
             const sampleCoord = uv + p5.vec2(sample, sample) / inputs.canvasSize * direction;
             const weight = quadWeight(sample, (numSamples - 1.0) * 0.5 * spacing);
 
-            avg += weight * p5.getTexture(canvasContent, sampleCoord);
+            const texSample = p5.getTexture(canvasContent , sampleCoord);
+            avg += weight * (texSample * p5.vec4(
+              texSample.a, texSample.a, texSample.a, 1
+            ));
             total += weight;
           }
 
-          return avg / total;
+          const blended = avg / total;
+
+          return p5.vec4(
+            blended.r / blended.a,
+            blended.g / blended.a,
+            blended.b / blended.a,
+            blended.a
+          );
         });
       }, { p5 });