1 files changed, 10 insertions, 1 deletions
diff --git a/src/fshader_test.glsl b/src/fshader_test.glsl
index 95458ee..9e41d92 100644
--- a/src/fshader_test.glsl
+++ b/src/fshader_test.glsl
@@ -3,6 +3,15 @@
 %COMMON%
 %SDF%
 
+IN vec2 pos;
+
+vec4 rand(vec2 coord) {
+	// this seems to give pretty good quality noise for |coord| < 2
+	vec4 a = sin((coord.xyyx + vec4(3.0)) * (coord.xyxy + vec4(4.0)) * 100.0 + 0.5832) * 1618.0;
+	vec4 b = sin((coord.xyyx + vec4(3.0)) * (coord.xyxy + vec4(4.0)) * 222.0 + 5.1339) * 2412.0;
+	return vec4(fract(a.xy + a.zw), fract(b.xy + b.zw));
+}
+
 void main() {
-	gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+	gl_FragColor = vec4(rand(pos));//sdf(8.0 * rand(pos).xyz - 4.0));
 }