texture example

Author: substack

webgl/tex.js

@@ -0,0 +1,135 @@
+var regl = require('regl')()
+var camera = require('regl-camera')(regl,
+  { distance: 5 })
+var icosphere = require('icosphere')
+var mesh = icosphere(3)
+var glsl = require('glslify')
+var anormals = require('angle-normals')
+var resl = require('resl')
+
+function createBlob () {
+  return regl({
+    frag: glsl`
+      precision highp float;
+      #pragma glslify: snoise = require('glsl-noise/simplex/4d')
+      #pragma glslify: hsl2rgb = require('glsl-hsl2rgb')
+      uniform float time;
+      varying vec3 vpos;
+      void main () {
+        float h = (snoise(vec4(vpos,time))*0.5+0.5)*0.4+0.5;
+        float s = 0.5;
+        float l = 0.5;
+        gl_FragColor = vec4(hsl2rgb(h,s,l),1);
+      }
+    `,
+    vert: glsl`
+      precision highp float;
+      #pragma glslify: snoise = require('glsl-noise/simplex/4d')
+      attribute vec3 position, normal;
+      uniform mat4 projection, view;
+      uniform float time, iblob;
+      uniform vec3 offset;
+      varying vec3 vpos;
+      void main () {
+        vec3 p = position + offset
+          + vec3(
+            sin(iblob*0.9+time*0.1)*20.0,
+            cos(iblob*0.7+time*0.1)*3.0,
+            sin(iblob*0.8+time*0.1)*23.0
+          );
+        float n = snoise(vec4(p,time*0.2));
+        vpos = p + normal * n * 0.8;
+        gl_Position = projection * view * vec4(vpos,1);
+      }
+    `,
+    uniforms: {
+      time: regl.context('time'),
+      offset: regl.prop('offset'),
+      iblob: regl.prop('iblob')
+    },
+    attributes: {
+      position: mesh.positions,
+      normal: anormals(mesh.cells, mesh.positions)
+    },
+    elements: mesh.cells
+  })
+}
+
+function createBG (imgdata) {
+  return regl({
+    frag: glsl`
+      precision highp float;
+      #pragma glslify: snoise = require('glsl-noise/simplex/3d')
+      #pragma glslify: hsl2rgb = require('glsl-hsl2rgb')
+      varying vec2 vpos;
+      uniform float time;
+      uniform sampler2D img;
+      void main () {
+        float n0 = snoise(vec3(vpos,time))*0.5+0.5;
+        float n1 = snoise(vec3(vpos,time+1.0));
+        float n2 = snoise(vec3(vpos,time+2.0));
+        float h = n0*0.4+0.4
+          + (snoise(vec3(vpos*4.0,time*2.0))*0.5+0.5)*0.2+0.2;
+        float s = n0*0.2+0.8;
+        float l = pow((snoise(vec3(vpos*8.0,time))*0.5+0.5),3.0);
+        vec2 uv = vec2(vpos.x,-vpos.y)*0.5+0.5;
+        vec3 px = texture2D(img,uv+0.1*vec2(n1,n2)).rgb;
+        gl_FragColor = vec4(hsl2rgb(h,s,l)+px,1);
+      }
+    `,
+    vert: glsl`
+      precision highp float;
+      attribute vec2 position;
+      varying vec2 vpos;
+      void main () {
+        vpos = position;
+        gl_Position = vec4(position,0,1);
+      }
+    `,
+    uniforms: {
+      time: regl.context('time'),
+      img: regl.texture(imgdata)
+    },
+    attributes: {
+      position: [-4,4,-4,-4,4,0]
+    },
+    elements: [[0,1,2]],
+    count: 3,
+    depth: {
+      enable: false,
+      mask: false
+    }
+  })
+}
+
+var blobs = []
+for (var i = 0; i < 100; i++) {
+  var x = (Math.random()*2-1) * 20
+  var y = (Math.random()*2-1) * 5
+  var z = (Math.random()*2-1) * 20
+  blobs.push({ offset: [x,y,z], iblob: i })
+}
+
+var draw = {
+  blob: createBlob()
+}
+resl({
+  manifest: {
+    cat: {
+      type: 'image',
+      src: 'cat.jpg'
+    }
+  },
+  onDone: ready
+})
+function ready (assets) {
+  draw.bg = createBG(assets.cat)
+}
+
+regl.frame(function () {
+  regl.clear({ color: [0,0,0,1], depth: true })
+  if (draw.bg) draw.bg()
+  camera(function () {
+    draw.blob(blobs)
+  })
+})