Add subscribeUniform extension pipeline

gpu/command_buffer/service/program_manager.cc

Index: gpu/command_buffer/service/program_manager.cc
diff --git a/gpu/command_buffer/service/program_manager.cc b/gpu/command_buffer/service/program_manager.cc
index ac7021ad7f752a2ecd4bf312378e6df77f5f2416..cd1b74a141acbd080634223f1648d23127a0d5b8 100644
--- a/gpu/command_buffer/service/program_manager.cc
+++ b/gpu/command_buffer/service/program_manager.cc
@@ -193,8 +193,7 @@ bool ProgramManager::IsInvalidPrefix(const char* name, size_t length) {
       memcmp(name, kInvalidPrefix, sizeof(kInvalidPrefix)) == 0);
 }
 
-Program::Program(
-    ProgramManager* manager, GLuint service_id)
+Program::Program(ProgramManager* manager, GLuint service_id)
     : manager_(manager),
       use_count_(0),
       max_attrib_name_length_(0),
@@ -204,6 +203,7 @@ Program::Program(
       valid_(false),
       link_status_(false),
       uniforms_cleared_(false),
+      needs_update_subscriptions_(true),
       num_uniforms_(0) {
   manager_->StartTracking(this);
 }
@@ -211,6 +211,7 @@ Program::Program(
 void Program::Reset() {
   valid_ = false;
   link_status_ = false;
+  needs_update_subscriptions_ = true;
   num_uniforms_ = 0;
   max_uniform_name_length_ = 0;
   max_attrib_name_length_ = 0;
@@ -635,6 +636,10 @@ void Program::Validate() {
   UpdateLogInfo();
 }
 
+void Program::SetNeedsUpdateSubscriptions() {
+  needs_update_subscriptions_ = true;

[piman, 2014/10/23 02:30:48]

When will that be reset to false? In
GLES2DecoderImpl::PopulateSubscribedUniforms when implemented? Should it be done
now?

+}
+
 GLint Program::GetUniformFakeLocation(
     const std::string& name) const {
   bool getting_array_location = false;
@@ -1198,6 +1203,14 @@ bool Program::CheckVaryingsPacking(
       combined_map.size()) == 1;
 }
 
+void Program::AddSubscription(GLint location, GLenum target) {
+  subscription_map_[location] = target;
+}
+
+void Program::RemoveSubscription(GLint location) {
+  subscription_map_.erase(location);
+}
+
 static uint32 ComputeOffset(const void* start, const void* position) {
   return static_cast<const uint8*>(position) -
          static_cast<const uint8*>(start);
@@ -1364,6 +1377,15 @@ bool ProgramManager::IsOwned(Program* program) {
   return false;
 }
 
+void ProgramManager::ActivateUniformSubscriptionState() {

[brianderson, 2014/10/24 00:28:34]

It looks like ProgramManager has a 1:1 relationship with a ContextGroup, however
we'll likely want activations to only apply to a single context and not all
contexts within the group. Should this be a method on ContextState instead?

Ditto for other state like the subscription_map_.

+  // TODO(orglofch): Make active_state = pending_state
+  // only set needs update subscriptions if !pending_state.empty()
+  for (ProgramMap::iterator it = programs_.begin(); it != programs_.end();
+       ++it) {

[piman, 2014/10/23 02:30:48]

Maybe make it a TODO, but it would be nice not to have to iterate over all the
programs, given that it's likely that only a few have subscriptions.

Hence the idea to use a generation number.

+    it->second.get()->SetNeedsUpdateSubscriptions();
+  }
+}
+
 void ProgramManager::RemoveProgramInfoIfUnused(
     ShaderManager* shader_manager, Program* program) {
   DCHECK(shader_manager);
@@ -1417,5 +1439,15 @@ int32 ProgramManager::MakeFakeLocation(int32 index, int32 element) {
   return index + element * 0x10000;
 }
 
+Program::UniformApiType ProgramManager::ApiTypeForSubscriptionTarget(
+    GLenum target) {
+  switch (target) {
+    case GL_MOUSE_POSITION_CHROMIUM:
+      return Program::kUniform2i;
+  }
+  NOTREACHED() << "Unhandled uniform subscription target " << target;
+  return Program::kUniformNone;
+}
+
 }  // namespace gles2
 }  // namespace gpu