Use client side arrays for GL_STREAM_DRAW attributes

gpu/command_buffer/service/feature_info.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/feature_info.h"
 
 #include <set>
 
 #include "base/command_line.h"
 #include "base/string_number_conversions.h"
@@ skipping 76 matching lines @@
 FeatureInfo::Workarounds::Workarounds()
     : clear_alpha_in_readpixels(false),
       needs_glsl_built_in_function_emulation(false),
       needs_offscreen_buffer_workaround(false),
       reverse_point_sprite_coord_origin(false),
       set_texture_filter_before_generating_mipmap(false),
       use_current_program_after_successful_link(false),
       restore_scissor_on_fbo_change(false),
       flush_on_context_switch(false),
       delete_instead_of_resize_fbo(false),
+      use_client_side_arrays_for_stream_buffers(false),
       max_texture_size(0),
       max_cube_map_texture_size(0) {
 }
 
 FeatureInfo::FeatureInfo() {
   static const GLenum kAlphaTypes[] = {
       GL_UNSIGNED_BYTE,
   };
   static const GLenum kRGBTypes[] = {
       GL_UNSIGNED_BYTE,
@@ skipping 54 matching lines @@
   static GLenum string_ids[] = {
     GL_VENDOR,
     GL_RENDERER,
   };
   bool is_intel = false;
   bool is_nvidia = false;
   bool is_amd = false;
   bool is_mesa = false;
   bool is_qualcomm = false;
   bool is_imagination = false;
+  bool is_arm = false;
   for (size_t ii = 0; ii < arraysize(string_ids); ++ii) {
     const char* str = reinterpret_cast<const char*>(
           glGetString(string_ids[ii]));
     if (str) {
       std::string lstr(StringToLowerASCII(std::string(str)));
       StringSet string_set(lstr);
       is_intel |= string_set.Contains("intel");
       is_nvidia |= string_set.Contains("nvidia");
       is_amd |= string_set.Contains("amd") || string_set.Contains("ati");
       is_mesa |= string_set.Contains("mesa");
       is_qualcomm |= string_set.Contains("qualcomm");
       is_imagination |= string_set.Contains("imagination");
+      is_arm |= string_set.Contains("arm");
     }
   }
 
   feature_flags_.disable_workarounds =
       CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kDisableGpuDriverBugWorkarounds);
 
   feature_flags_.enable_shader_name_hashing =
       !CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kDisableShaderNameHashing);
 
-
   bool npot_ok = false;
 
   AddExtensionString("GL_ANGLE_translated_shader_source");
   AddExtensionString("GL_CHROMIUM_async_pixel_transfers");
   AddExtensionString("GL_CHROMIUM_bind_uniform_location");
   AddExtensionString("GL_CHROMIUM_command_buffer_query");
   AddExtensionString("GL_CHROMIUM_command_buffer_latency_query");
   AddExtensionString("GL_CHROMIUM_copy_texture");
   AddExtensionString("GL_CHROMIUM_discard_backbuffer");
   AddExtensionString("GL_CHROMIUM_get_error_query");
@@ skipping 125 matching lines @@
     }
     validators_.render_buffer_format.AddValue(GL_DEPTH24_STENCIL8);
   }
 
   if (extensions.Contains("GL_OES_vertex_array_object") ||
       extensions.Contains("GL_ARB_vertex_array_object") ||
       extensions.Contains("GL_APPLE_vertex_array_object")) {
     feature_flags_.native_vertex_array_object = true;
   }
 
+  // If the driver doesn't like uploading lots of buffer data constantly
+  // work around it by using client side arrays.
+  if (is_arm || is_imagination) {
+    workarounds_.use_client_side_arrays_for_stream_buffers = true;
+  }
+
+  // If we're using client_side_arrays we have to emulate
+  // vertex array objects since vertex array objects do not work
+  // with client side arrays.
+  if (workarounds_.use_client_side_arrays_for_stream_buffers) {
+    feature_flags_.native_vertex_array_object = false;
+  }
+
   if (extensions.Contains("GL_OES_element_index_uint") ||
       gfx::HasDesktopGLFeatures()) {
     AddExtensionString("GL_OES_element_index_uint");
     validators_.index_type.AddValue(GL_UNSIGNED_INT);
   }
 
   bool enable_texture_format_bgra8888 = false;
   bool enable_read_format_bgra = false;
   // Check if we should allow GL_EXT_texture_format_BGRA8888
   if (extensions.Contains("GL_EXT_texture_format_BGRA8888") ||
@@ skipping 304 matching lines @@
   if (extensions_.find(str) == std::string::npos) {
     extensions_ += (extensions_.empty() ? "" : " ") + str;
   }
 }
 
 FeatureInfo::~FeatureInfo() {
 }
 
 }  // namespace gles2
 }  // namespace gpu