From 25a26f353ba16cb91446fe27a3d7b43dad3983f0 Mon Sep 17 00:00:00 2001
From: Leonard Francis Coogan <leocoogan@mailfence.com>
Date: Wed, 27 Aug 2025 10:21:47 -0400
Subject: [PATCH] test shader

---
 shader_test/shader.frag |  6 ++++++
 shader_test/shader.vert | 23 +++++++++++++++++++++++
 shader_test/sketch.js   | 15 +++++++++++++++
 3 files changed, 44 insertions(+)
 create mode 100644 shader_test/shader.frag
 create mode 100644 shader_test/shader.vert
 create mode 100644 shader_test/sketch.js

diff --git a/shader_test/shader.frag b/shader_test/shader.frag
new file mode 100644
index 0000000..12a87ae
--- /dev/null
+++ b/shader_test/shader.frag
@@ -0,0 +1,6 @@
+precision highp float;
+
+void main() {
+  vec4 myColor = vec4(1.0, 0.0, 0.0, 1.0);
+  gl_FragColor = myColor;
+}
diff --git a/shader_test/shader.vert b/shader_test/shader.vert
new file mode 100644
index 0000000..d161189
--- /dev/null
+++ b/shader_test/shader.vert
@@ -0,0 +1,23 @@
+precision highp float;
+
+attribute vec3 aPosition;
+
+// The transform of the object being drawn
+uniform mat4 uModelViewMatrix;
+
+// Transforms 3D coordinates to 2D screen coordinates
+uniform mat4 uProjectionMatrix;
+
+// A custom uniform with the time in milliseconds
+uniform float time;
+
+void main() {
+  // Apply the camera transform
+  vec4 viewModelPosition = uModelViewMatrix * vec4(aPosition, 1.0);
+
+  // Use the time to adjust the position of the vertices
+  viewModelPosition.x += 10.0 * sin(time * 0.01 + viewModelPosition.y * 0.1);
+
+  // Tell WebGL where the vertex goes
+  gl_Position = uProjectionMatrix * viewModelPosition;  
+}
diff --git a/shader_test/sketch.js b/shader_test/sketch.js
new file mode 100644
index 0000000..bc60cbb
--- /dev/null
+++ b/shader_test/sketch.js
@@ -0,0 +1,15 @@
+let myShader;
+function preload() {
+  // load each shader file (don't worry, we will come back to these!)
+  myShader = loadShader('shader.vert', 'shader.frag');
+}
+function setup() {
+  // the canvas has to be created with WEBGL mode
+  createCanvas(windowWidth, windowHeight, WEBGL);
+}
+function draw() {
+  // shader() sets the active shader, which will be applied to what is drawn next
+  shader(myShader);
+  // apply the shader to a rectangle taking up the full canvas
+  plane(width, height);
+}