diff --git a/libs/gfx/source/effect/blur.cpp b/libs/gfx/source/effect/blur.cpp
index fff3d60f..2d00238a 100644
--- a/libs/gfx/source/effect/blur.cpp
+++ b/libs/gfx/source/effect/blur.cpp
@@ -55,9 +55,15 @@ void main()
 	vec4 result = vec4(0.0);
 	for (int i = -BLUR_SIZE; i <= BLUR_SIZE; ++i)
 	{
-		result += texture(u_texture, texcoord + float(i) * direction * u_inv_texture_size) * coeffs[i + BLUR_SIZE];
+		vec4 p = texture(u_texture, texcoord + float(i) * direction * u_inv_texture_size);
+		float c = coeffs[i + BLUR_SIZE];
+		result.rgb += p.rgb * p.a * c;
+		result.a += p.a * c;
 	}
-	out_color = result;
+	if (result.a == 0.0)
+		out_color = result;
+	else
+		out_color = vec4(result.rgb / result.a, result.a);
 }
 )";