From c0d19f102ab0e09532ca2aec294c335491dad206 Mon Sep 17 00:00:00 2001
From: Emile Clark-Boman <eclarkboman@gmail.com>
Date: Sat, 31 Jan 2026 11:32:09 +1000
Subject: [PATCH] fix uTime uniform

---
 www/js/draw-scene.js      |  4 ++--
 www/shaders/segfault.glsl | 13 ++++++++-----
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/www/js/draw-scene.js b/www/js/draw-scene.js
index f407c6d..d325b87 100644
--- a/www/js/draw-scene.js
+++ b/www/js/draw-scene.js
@@ -5,7 +5,7 @@ function drawScene(gl, programInfo, buffers, time) {
 
   // NOTE: this is how width/height is taken
   // const aspect = gl.canvas.clientWidth / gl.canvas.clientHeight;
-  
+
   // Tell WebGL how to pull out the positions from the position
   // buffer into the vertexPosition attribute.
   setPositionAttribute(gl, buffers, programInfo);
@@ -17,7 +17,7 @@ function drawScene(gl, programInfo, buffers, time) {
   gl.uniform1f(
     programInfo.uniformLocations.time,
     time,
-  );  
+  );
 
   {
     const offset = 0;
diff --git a/www/shaders/segfault.glsl b/www/shaders/segfault.glsl
index 9448d14..cd0474d 100644
--- a/www/shaders/segfault.glsl
+++ b/www/shaders/segfault.glsl
@@ -4,8 +4,11 @@
  * View this shader on shadertoy: https://www.shadertoy.com/view/t3tSRj#
  */
 
+#ifdef GL_ES
 precision highp float;
+#endif
 
+uniform float uTime;
 /* ==== Text Colouring  ==== */
 #define PHOSPHOR_COL vec4(1, 1., 1., 1.)
 #define BG_COL vec4(0.2, 0.0, 0.2, 0.)
@@ -296,7 +299,7 @@ float vt220Font(vec2 p, float c) {
 //     https://www.shadertoy.com/view/MsdGWn
 //
 float textLines(vec2 uvG) {
-    float wt = 5. * (iTime + 0.5*sin(iTime*1.4) + 0.2*sin(iTime*2.9)); // wobbly time
+    float wt = 5. * (uTime + 0.5*sin(uTime*1.4) + 0.2*sin(uTime*2.9)); // wobbly time
     vec2 uvGt = uvG + vec2(0., floor(wt));
     float ll = rand(vec2(uvGt.y, - 1.)) * ROWCOLS.x; // line length
     
@@ -362,12 +365,12 @@ void mainImage(out vec4 fragColor, in vec2 fragCoord) {
     uvNoise = ceil(uvNoise * ROWCOLS) / ROWCOLS;
     
     float val;
-    if (iTime < 2.0)
+    if (uTime < 2.0)
         val = textLines(uvG);
-    else if (iTime < 2.3)
-        val = rand(uvG * iTime) * 17.;
+    else if (uTime < 2.3)
+        val = rand(uvG * uTime) * 17.;
     else {
-        float noise = smokeNoise(vec3(uvNoise * noiseScale, iTime * noiseTimeScale));
+        float noise = smokeNoise(vec3(uvNoise * noiseScale, uTime * noiseTimeScale));
         // Noise is fed through a sigmoid function, then quantised to integer range 0-17
         val = (exp(noise) / 2.71828);  // increase contrast (normalised 0.0 - 1.0)
         val = 1.0 / val;