WebGL 2: make sure VertexAttrib type match the corresponding attrib type in shader

gpu/command_buffer/service/context_state.h

Index: gpu/command_buffer/service/context_state.h
diff --git a/gpu/command_buffer/service/context_state.h b/gpu/command_buffer/service/context_state.h
index d026df9a06fd38c22f76e0d508d994063614921c..a8f573accc663f33cc1c6c56dc3a3712f3177297 100644
--- a/gpu/command_buffer/service/context_state.h
+++ b/gpu/command_buffer/service/context_state.h
@@ -243,6 +243,31 @@ struct GPU_EXPORT ContextState {
   void SetBoundBuffer(GLenum target, Buffer* buffer);
   void RemoveBoundBuffer(Buffer* buffer);
 
+  void InitGenericAttribBaseType(GLuint max_vertex_attribs) {
+      max_vertex_attribs_ = max_vertex_attribs;
+
+      uint32_t packed_size = max_vertex_attribs_ / 16;

[Zhenyao Mo, 2016/07/22 14:36:47]

nit: this can be ceil(), but your code is also correct.

+      packed_size += (max_vertex_attribs_ % 16 == 0) ? 0 : 1;
+      generic_attrib_base_type_mask_.resize(packed_size);
+      for (uint32_t i = 0; i < packed_size; ++i) {
+        generic_attrib_base_type_mask_[i] = 0xFFFFFFFF;

[Zhenyao Mo, 2016/07/22 14:36:47]

set this to be 0x55555555 * SHADER_VARIABLE_FLOAT
see
https://cs.chromium.org/chromium/src/gpu/command_buffer/service/framebuffer_m...
Otherwise it's hard to read what's going on here.

+      }
+  }
+
+  void SetGenericVertexAttribBaseType(GLuint index, GLenum base_type) {
+    DCHECK(index < max_vertex_attribs_);
+    int shift_bits = (index % 16) * 2;
+    generic_attrib_base_type_mask_[index / 16] &= ~(0x3 << shift_bits);
+    generic_attrib_base_type_mask_[index / 16] |= (base_type << shift_bits);
+  }
+
+  // Return 16 attributes' base types, in which the generic attribute
+  // specified by argument 'index' located.
+  uint32_t GetGenericVertexAttribBaseTypeMask(GLuint index) {
+    DCHECK(index < max_vertex_attribs_);
+    return generic_attrib_base_type_mask_[index / 16];
+  }
+
   void UnbindTexture(TextureRef* texture);
   void UnbindSampler(Sampler* sampler);
 
@@ -320,6 +345,12 @@ struct GPU_EXPORT ContextState {
 
   bool framebuffer_srgb_;
 
+  uint32_t max_vertex_attribs_;
+  // Generic vertex attrib base types: FLOAT, INT, or UINT.
+  // Each base type is encoded into 2 bits, the lowest 2 bits for location 0,
+  // the highest 2 bits for location (max_vertex_attribs_ - 1).
+  std::vector<uint32_t> generic_attrib_base_type_mask_;
+
   FeatureInfo* feature_info_;
   std::unique_ptr<ErrorState> error_state_;
 };