Implement GLES2 glShaderBinary and glReleaseShaderCompiler functions as no-op stubs. Add a machinery for glGetError() to report errors generated by the library_gl.js interop layer.

1 files changed, 33 insertions, 10 deletions

diff --git a/src/library_gl.js b/src/library_gl.js
index 7074f844..15eb0d52 100644
--- a/src/library_gl.js
+++ b/src/library_gl.js
@@ -11,6 +11,7 @@ var LibraryGL = {
 #endif
 
     counter: 1, // 0 is reserved as 'null' in gl
+    lastError: 0,
     buffers: [],
     programs: [],
     framebuffers: [],
@@ -51,6 +52,13 @@ var LibraryGL = {
       Browser.moduleContextCreatedCallbacks.push(GL.initExtensions);
     },
 
+    // Records a GL error condition that occurred, stored until user calls glGetError() to fetch it. As per GLES2 spec, only the first error 
+    // is remembered, and subsequent errors are discarded until the user has cleared the stored error by a call to glGetError().
+    recordError: function recordError(errorCode) {
+      if (!GL.lastError) {
+        GL.lastError = errorCode;
+      }
+    },
     // Get a new ID for a texture/buffer/etc., while keeping the table dense and fast. Creation is farely rare so it is worth optimizing lookups later.
     getNewId: function(table) {
       var ret = GL.counter++;
@@ -2123,9 +2131,6 @@ var LibraryGL = {
   glGetShaderPrecisionFormat__sig: 'v',
   glGetShaderPrecisionFormat: function() { throw 'glGetShaderPrecisionFormat: TODO' },
 
-  glShaderBinary__sig: 'v',
-  glShaderBinary: function() { throw 'glShaderBinary: TODO' },
-
   glDeleteObject__sig: 'vi',
   glDeleteObject: function(id) {
     if (GL.programs[id]) {
@@ -2137,11 +2142,6 @@ var LibraryGL = {
     }
   },
 
-  glReleaseShaderCompiler__sig: 'v',
-  glReleaseShaderCompiler: function() {
-    // NOP (as allowed by GLES 2.0 spec)
-  },
-
   glGetObjectParameteriv__sig: 'viii',
   glGetObjectParameteriv: function(id, type, result) {
     if (GL.programs[id]) {
@@ -4618,6 +4618,30 @@ var LibraryGL = {
 #endif
   },
 
+  glShaderBinary__sig: 'v',
+  glShaderBinary: function() {
+    GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+    Module.printErr("GL_INVALID_ENUM in glShaderBinary: WebGL does not support binary shader formats! Calls to glShaderBinary always fail.");
+#endif    
+  },
+
+  glReleaseShaderCompiler__sig: 'v',
+  glReleaseShaderCompiler: function() {
+    // NOP (as allowed by GLES 2.0 spec)
+  },
+
+  glGetError__sig: 'i',
+  glGetError: function() {
+    // First return any GL error generated by the emscripten library_gl.js interop layer.
+    if (GL.lastError) {
+      var error = GL.lastError;
+      GL.lastError = 0/*GL_NO_ERROR*/;
+      return error;
+    } else { // If there were none, return the GL error from the browser GL context.
+      return Module.ctx.getError();
+    }
+  },
   // signatures of simple pass-through functions, see later
 
   glActiveTexture__sig: 'vi',
@@ -4651,14 +4675,13 @@ var LibraryGL = {
   glFlush__sig: 'v',
   glClearColor__sig: 'viiii',
   glIsEnabled__sig: 'ii',
-  glGetError__sig: 'i',
   glFrontFace__sig: 'vi',
   glSampleCoverage__sig: 'vi',
 };
 
 
 // Simple pass-through functions. Starred ones have return values. [X] ones have X in the C name but not in the JS name
-[[0, 'getError* finish flush'],
+[[0, 'finish flush'],
  [1, 'clearDepth clearDepth[f] depthFunc enable disable frontFace cullFace clear lineWidth clearStencil depthMask stencilMask checkFramebufferStatus* generateMipmap activeTexture blendEquation sampleCoverage isEnabled*'],
  [2, 'blendFunc blendEquationSeparate depthRange depthRange[f] stencilMaskSeparate hint polygonOffset vertexAttrib1f'],
  [3, 'texParameteri texParameterf vertexAttrib2f stencilFunc stencilOp'],