cc/output/program_binding.cc

   1 // Copyright 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "cc/output/program_binding.h"
   6
   7 #include "base/debug/trace_event.h"
   8 #include "cc/output/geometry_binding.h"
   9 #include "gpu/command_buffer/client/gles2_interface.h"
  10 #include "third_party/khronos/GLES2/gl2.h"
  11
  12 using gpu::gles2::GLES2Interface;
  13
  14 namespace cc {
  15
  16 ProgramBindingBase::ProgramBindingBase()
  17     : program_(0),
  18       vertex_shader_id_(0),
  19       fragment_shader_id_(0),
  20       initialized_(false) {}
  21
  22 ProgramBindingBase::~ProgramBindingBase() {
  23   // If you hit these asserts, you initialized but forgot to call Cleanup().
  24   DCHECK(!program_);
  25   DCHECK(!vertex_shader_id_);
  26   DCHECK(!fragment_shader_id_);
  27   DCHECK(!initialized_);
  28 }
  29
  30 bool ProgramBindingBase::Init(GLES2Interface* context,
  31                               const std::string& vertex_shader,
  32                               const std::string& fragment_shader) {
  33   TRACE_EVENT0("cc", "ProgramBindingBase::init");
  34   vertex_shader_id_ = LoadShader(context, GL_VERTEX_SHADER, vertex_shader);
  35   if (!vertex_shader_id_)
  36     return false;
  37
  38   fragment_shader_id_ =
  39       LoadShader(context, GL_FRAGMENT_SHADER, fragment_shader);
  40   if (!fragment_shader_id_) {
  41     context->DeleteShader(vertex_shader_id_);
  42     vertex_shader_id_ = 0;
  43     return false;
  44   }
  45
  46   program_ =
  47       CreateShaderProgram(context, vertex_shader_id_, fragment_shader_id_);
  48   return !!program_;
  49 }
  50
  51 bool ProgramBindingBase::Link(GLES2Interface* context) {
  52   context->LinkProgram(program_);
  53   CleanupShaders(context);
  54   if (!program_)
  55     return false;
  56 #ifndef NDEBUG
  57   int linked = 0;
  58   context->GetProgramiv(program_, GL_LINK_STATUS, &linked);
  59   if (!linked)
  60     return false;
  61 #endif
  62   return true;
  63 }
  64
  65 void ProgramBindingBase::Cleanup(GLES2Interface* context) {
  66   initialized_ = false;
  67   if (!program_)
  68     return;
  69
  70   DCHECK(context);
  71   context->DeleteProgram(program_);
  72   program_ = 0;
  73
  74   CleanupShaders(context);
  75 }
  76
  77 unsigned ProgramBindingBase::LoadShader(GLES2Interface* context,
  78                                         unsigned type,
  79                                         const std::string& shader_source) {
  80   unsigned shader = context->CreateShader(type);
  81   if (!shader)
  82     return 0u;
  83
  84   const char* shader_source_str[] = { shader_source.data() };
  85   int shader_length[] = { static_cast<int>(shader_source.length()) };
  86   context->ShaderSource(
  87       shader, 1,
  88       shader_source_str,
  89       shader_length);
  90   context->CompileShader(shader);
  91 #ifndef NDEBUG
  92   int compiled = 0;
  93   context->GetShaderiv(shader, GL_COMPILE_STATUS, &compiled);
  94   if (!compiled)
  95     return 0u;
  96 #endif
  97   return shader;
  98 }
  99
 100 unsigned ProgramBindingBase::CreateShaderProgram(GLES2Interface* context,
 101                                                  unsigned vertex_shader,
 102                                                  unsigned fragment_shader) {
 103   unsigned program_object = context->CreateProgram();
 104   if (!program_object)
 105     return 0;
 106
 107   context->AttachShader(program_object, vertex_shader);
 108   context->AttachShader(program_object, fragment_shader);
 109
 110   // Bind the common attrib locations.
 111   context->BindAttribLocation(
 112       program_object, GeometryBinding::PositionAttribLocation(), "a_position");
 113   context->BindAttribLocation(
 114       program_object, GeometryBinding::TexCoordAttribLocation(), "a_texCoord");
 115   context->BindAttribLocation(program_object,
 116                               GeometryBinding::TriangleIndexAttribLocation(),
 117                               "a_index");
 118
 119   return program_object;
 120 }
 121
 122 void ProgramBindingBase::CleanupShaders(GLES2Interface* context) {
 123   if (vertex_shader_id_) {
 124     context->DeleteShader(vertex_shader_id_);
 125     vertex_shader_id_ = 0;
 126   }
 127   if (fragment_shader_id_) {
 128     context->DeleteShader(fragment_shader_id_);
 129     fragment_shader_id_ = 0;
 130   }
 131 }
 132
 133 }  // namespace cc