Adds automatic precision qualifier

Author: stephomi

src/render/shaders/ShaderBackground.js

@@ -20,7 +20,6 @@ ShaderBackground.vertex = [
 ].join('\n');
 
 ShaderBackground.fragment = [
-  'precision mediump float;',
   'uniform sampler2D uTexture0;',
   'varying vec2 vTexCoord;',
   ShaderBase.strings.colorSpaceGLSL,

src/render/shaders/ShaderBase.js

@@ -62,22 +62,35 @@ ShaderBase.strings.fragColorFunction = [
   '}'
 ].join('\n');
 
-var moveExtension = function (str) {
+var processShader = function (str) {
   // move extension enable/require to the top of file
+  var extensions = '';
   var matches = str.match(/^\s*(#extension).*/gm);
-  if (!matches) return str;
-  var extMap = {};
-  var exts = '';
-
-  for (var i = 0, nb = matches.length; i < nb; ++i) {
-    var ext = matches[i].substr(matches[i].indexOf('#extension'));
-    str = str.replace(matches[i], '');
-    if (extMap[ext])
-      continue;
-    extMap[ext] = true;
-    exts += ext + '\n';
+  if (matches) {
+    var extMap = {};
+
+    for (var i = 0, nb = matches.length; i < nb; ++i) {
+      var ext = matches[i].substr(matches[i].indexOf('#extension'));
+      str = str.replace(matches[i], '');
+      if (extMap[ext])
+        continue;
+      extMap[ext] = true;
+      extensions += ext + '\n';
+    }
   }
-  str = exts + str;
+
+  var version = '';
+  if (str.indexOf('#version') === -1) {
+    version += '#version 100\n';
+  }
+
+  var precision = '';
+  var regPrecision = /precision\s+(high|low|medium)p\s+float/;
+  if (!regPrecision.test(str)) {
+    precision += '#ifdef GL_FRAGMENT_PRECISION_HIGH\n  precision highp float;\n#else\n  precision mediump float;\n#endif\n';
+  }
+
+  str = version + extensions + precision + str;
   return str;
 };
 
@@ -89,11 +102,11 @@ ShaderBase.getOrCreate = function (gl) {
   var fname = '\n#define SHADER_NAME ' + this.fragmentName + '\n';
 
   var vShader = gl.createShader(gl.VERTEX_SHADER);
-  gl.shaderSource(vShader, moveExtension(this.vertex + vname));
+  gl.shaderSource(vShader, processShader(this.vertex + vname));
   gl.compileShader(vShader);
 
   var fShader = gl.createShader(gl.FRAGMENT_SHADER);
-  gl.shaderSource(fShader, moveExtension(this.fragment + fname));
+  gl.shaderSource(fShader, processShader(this.fragment + fname));
   gl.compileShader(fShader);
 
   var program = this.program = gl.createProgram();

src/render/shaders/ShaderContour.js

@@ -23,7 +23,6 @@ ShaderContour.vertex = [
 
 ShaderContour.fragment = [
   '#extension GL_OES_standard_derivatives : enable',
-  'precision mediump float;',
   'uniform sampler2D uTexture0;',
   'uniform vec4 uColor;',
   'varying vec2 vTexCoord;',

src/render/shaders/ShaderFlat.js

@@ -14,7 +14,6 @@ ShaderFlat.uniformNames = ['uColor'];
 Array.prototype.push.apply(ShaderFlat.uniformNames, ShaderBase.uniformNames.commonUniforms);
 
 ShaderFlat.vertex = [
-  'precision mediump float;',
   'attribute vec3 aVertex;',
   'attribute vec3 aMaterial;',
   ShaderBase.strings.vertUniforms,
@@ -26,7 +25,6 @@ ShaderFlat.vertex = [
 ].join('\n');
 
 ShaderFlat.fragment = [
-  'precision mediump float;',
   'uniform vec3 uColor;',
   'void main() {',
   '  gl_FragColor = vec4(uColor, 1.0);',

src/render/shaders/ShaderFxaa.js

@@ -14,7 +14,6 @@ ShaderFxaa.attributes = {};
 ShaderFxaa.uniformNames = ['uTexture0', 'uInvSize'];
 
 ShaderFxaa.vertex = [
-  'precision mediump float;',
   'attribute vec2 aVertex;',
   'uniform vec2 uInvSize;',
   'varying vec2 vUVNW;',
@@ -33,7 +32,6 @@ ShaderFxaa.vertex = [
 ].join('\n');
 
 ShaderFxaa.fragment = [
-  'precision mediump float;',
   'uniform sampler2D uTexture0;',
   'uniform vec2 uInvSize;',
   'varying vec2 vUVNW;',

src/render/shaders/ShaderMatcap.js

@@ -52,7 +52,6 @@ ShaderMatcap.uniformNames = ['uTexture0', 'uAlbedo'];
 Array.prototype.push.apply(ShaderMatcap.uniformNames, ShaderBase.uniformNames.commonUniforms);
 
 ShaderMatcap.vertex = [
-  'precision mediump float;',
   'attribute vec3 aVertex;',
   'attribute vec3 aNormal;',
   'attribute vec3 aColor;',
@@ -83,7 +82,6 @@ ShaderMatcap.vertex = [
 ].join('\n');
 
 ShaderMatcap.fragment = [
-  'precision mediump float;',
   'uniform sampler2D uTexture0;',
   'varying vec3 vVertex;',
   'varying vec3 vVertexPres;',

src/render/shaders/ShaderMerge.js

@@ -13,7 +13,6 @@ ShaderMerge.attributes = {};
 ShaderMerge.uniformNames = ['uTexture0', 'uTexture1', 'uFilmic'];
 
 ShaderMerge.vertex = [
-  'precision mediump float;',
   'attribute vec2 aVertex;',
   'varying vec2 vTexCoord;',
   'void main() {',
@@ -23,7 +22,6 @@ ShaderMerge.vertex = [
 ].join('\n');
 
 ShaderMerge.fragment = [
-  'precision mediump float;',
   'uniform sampler2D uTexture0;',
   'uniform sampler2D uTexture1;',
   'uniform int uFilmic;',

src/render/shaders/ShaderNormal.js

@@ -15,7 +15,6 @@ ShaderNormal.uniformNames = [];
 Array.prototype.push.apply(ShaderNormal.uniformNames, ShaderBase.uniformNames.commonUniforms);
 
 ShaderNormal.vertex = [
-  'precision mediump float;',
   'attribute vec3 aVertex;',
   'attribute vec3 aNormal;',
   'attribute vec3 aMaterial;',
@@ -35,7 +34,6 @@ ShaderNormal.vertex = [
 ].join('\n');
 
 ShaderNormal.fragment = [
-  'precision mediump float;',
   'varying vec3 vVertex;',
   'varying vec3 vNormal;',
   'uniform float uAlpha;',

src/render/shaders/ShaderPBR.js

@@ -43,7 +43,6 @@ ShaderPBR.uniformNames = ['uIblTransform', 'uTexture0', 'uAlbedo', 'uRoughness',
 Array.prototype.push.apply(ShaderPBR.uniformNames, ShaderBase.uniformNames.commonUniforms);
 
 ShaderPBR.vertex = [
-  'precision mediump float;',
   'attribute vec3 aVertex;',
   'attribute vec3 aNormal;',
   'attribute vec3 aColor;',
@@ -73,7 +72,6 @@ ShaderPBR.vertex = [
 ].join('\n');
 
 ShaderPBR.fragment = [
-  'precision mediump float;',
   'varying vec3 vVertex;',
   'varying vec3 vNormal;',
   'varying vec3 vAlbedo;',

src/render/shaders/ShaderSelection.js

@@ -20,7 +20,6 @@ ShaderSelection.vertex = [
 ].join('\n');
 
 ShaderSelection.fragment = [
-  'precision mediump float;',
   'uniform vec3 uColor;',
   'void main() {',
   '  gl_FragColor = vec4(uColor, 1.0);',

src/render/shaders/ShaderUV.js

@@ -13,7 +13,6 @@ ShaderUV.uniformNames = ['uTexture0', 'uAlbedo'];
 Array.prototype.push.apply(ShaderUV.uniformNames, ShaderBase.uniformNames.commonUniforms);
 
 ShaderUV.vertex = [
-  'precision mediump float;',
   'attribute vec3 aVertex;',
   'attribute vec3 aNormal;',
   'attribute vec3 aColor;',
@@ -40,7 +39,6 @@ ShaderUV.vertex = [
 ].join('\n');
 
 ShaderUV.fragment = [
-  'precision mediump float;',
   'uniform sampler2D uTexture0;',
   'varying vec3 vVertex;',
   'varying vec3 vNormal;',

src/render/shaders/ShaderWireframe.js

@@ -26,7 +26,6 @@ ShaderWireframe.vertex = [
 ].join('\n');
 
 ShaderWireframe.fragment = [
-  'precision mediump float;',
   'void main() {',
   '  gl_FragColor = vec4(0.0, 0.0, 0.0, 0.4);',
   '}'