gpu: Render to a framebuffer object instead of an offscreen surface in gpu_perftests.

gpu/perftests/texture_upload_perftest.cc

 // Copyright 2015 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 <algorithm>
 #include <vector>
 
 #include "base/containers/small_map.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 78 matching lines @@
 // PerfTest to check costs of texture upload at different stages
 // on different platforms.
 class TextureUploadPerfTest : public testing::Test {
  public:
   TextureUploadPerfTest() : size_(512, 512) {}
 
   // Overridden from testing::Test
   void SetUp() override {
     // Initialize an offscreen surface and a gl context.
     gfx::GLSurface::InitializeOneOff();
-    surface_ = gfx::GLSurface::CreateOffscreenGLSurface(size_);
+    surface_ = gfx::GLSurface::CreateOffscreenGLSurface(gfx::Size(4, 4));
     gl_context_ = gfx::GLContext::CreateGLContext(NULL,  // share_group
                                                   surface_.get(),
                                                   gfx::PreferIntegratedGpu);
+    ui::ScopedMakeCurrent smc(gl_context_.get(), surface_.get());
+    glGenTextures(1, &color_texture_);
+    glBindTexture(GL_TEXTURE_2D, color_texture_);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, size_.width(), size_.height(), 0,
+                 GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
 
-    ui::ScopedMakeCurrent smc(gl_context_.get(), surface_.get());
+    glGenFramebuffersEXT(1, &framebuffer_object_);
+    glBindFramebufferEXT(GL_FRAMEBUFFER, framebuffer_object_);
+
+    glFramebufferTexture2DEXT(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+                              GL_TEXTURE_2D, color_texture_, 0);
+    DCHECK_EQ(static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE),
+              glCheckFramebufferStatusEXT(GL_FRAMEBUFFER));
+
+    glViewport(0, 0, size_.width(), size_.height());
+
     if (gpu_timing_.Initialize(gl_context_.get())) {
       LOG(INFO) << "Gpu timing initialized with timer type: "
                 << gpu_timing_.GetTimerTypeName();
       gpu_timing_.CheckAndResetTimerErrors();
       gpu_timing_.InvalidateTimerOffset();
     } else {
       LOG(WARNING) << "Can't initialize gpu timing";
     }
-
     // Prepare a simple program and a vertex buffer that will be
     // used to draw a quad on the offscreen surface.
     vertex_shader_ = LoadShader(GL_VERTEX_SHADER, kVertexShader);
     fragment_shader_ = LoadShader(GL_FRAGMENT_SHADER, kFragmentShader);
     program_object_ = glCreateProgram();
     CHECK_NE(0u, program_object_);
 
     glAttachShader(program_object_, vertex_shader_);
     glAttachShader(program_object_, fragment_shader_);
     glBindAttribLocation(program_object_, 0, "a_position");
@@ skipping 23 matching lines @@
     }
     if (vertex_shader_ != 0) {
       glDeleteShader(vertex_shader_);
     }
     if (fragment_shader_ != 0) {
       glDeleteShader(fragment_shader_);
     }
     if (vertex_buffer_ != 0) {
       glDeleteShader(vertex_buffer_);
     }
+    if (framebuffer_object_ != 0) {

[reveman, 2015/02/18 16:21:33]

nit: I think just "if (framebuffer_object_)" is preferred but I can see "!= 0"
being used in this file already so you can keep this for consistency if you
like.

btw, do we really need all these "if" statements in TearDown? When is it OK for
framebuffer_object_ to be 0?

[Daniele Castagna, 2015/02/18 18:47:07]

We don't need them. I checked the documentation for all those functions and a
value of 0 is always ignored.

+      glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
+      glDeleteFramebuffersEXT(1, &framebuffer_object_);
+    }
+    if (color_texture_ != 0) {

[reveman, 2015/02/18 16:21:33]

nit: maybe remove "!= 0"

[Daniele Castagna, 2015/02/18 18:47:07]

Removed all the if (blabla_ != 0)

+      glDeleteTextures(1, &color_texture_);
+    }
 
     gl_context_ = nullptr;
     surface_ = nullptr;
   }
 
  protected:
   // Upload and draw on the offscren surface.
   // Return a list of pair. Each pair describe a gl operation and the wall
   // time elapsed in milliseconds.
   std::vector<Measurement> UploadAndDraw(const std::vector<uint8>& pixels,
                                          const GLenum format,
                                          const GLenum type) {
     ui::ScopedMakeCurrent smc(gl_context_.get(), surface_.get());
+    DCHECK_GT(framebuffer_object_, 0u);

[reveman, 2015/02/18 16:21:33]

nit: DCHECK_NE as less than 0 is not possible

[Daniele Castagna, 2015/02/18 18:47:07]

Done.

+    glBindFramebufferEXT(GL_FRAMEBUFFER, framebuffer_object_);
 
     MeasurementTimers total_timers(&gpu_timing_);
     GLuint texture_id = 0;
 
     MeasurementTimers tex_timers(&gpu_timing_);
     glActiveTexture(GL_TEXTURE0);
     glGenTextures(1, &texture_id);
     glBindTexture(GL_TEXTURE_2D, texture_id);
 
     glTexImage2D(GL_TEXTURE_2D, 0, format, size_.width(), size_.height(), 0,
                  format, type, &pixels[0]);
-    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     CheckNoGlError();
     tex_timers.Record();
 
     MeasurementTimers draw_timers(&gpu_timing_);
     glUseProgram(program_object_);
     glUniform1i(sampler_location_, 0);
 
     glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer_);
@@ skipping 22 matching lines @@
     EXPECT_EQ(pixels, pixels_rendered);
 
     std::vector<Measurement> measurements;
     measurements.push_back(total_timers.GetAsMeasurement("total"));
     measurements.push_back(tex_timers.GetAsMeasurement("teximage2d"));
     measurements.push_back(draw_timers.GetAsMeasurement("drawarrays"));
     measurements.push_back(finish_timers.GetAsMeasurement("finish"));
     return measurements;
   }
 
-  const gfx::Size size_;  // for the offscreen surface and the texture
+  const gfx::Size size_;  // for the fbo and the texture
   scoped_refptr<gfx::GLContext> gl_context_;
   scoped_refptr<gfx::GLSurface> surface_;
   GPUTiming gpu_timing_;
 
+  GLuint color_texture_ = 0;
+  GLuint framebuffer_object_ = 0;
   GLuint vertex_shader_ = 0;
   GLuint fragment_shader_ = 0;
   GLuint program_object_ = 0;
   GLint sampler_location_ = -1;
   GLuint vertex_buffer_ = 0;
 };
 
 // Perf test that generates, uploads and draws a texture on a surface repeatedly
 // and prints out aggregated measurements for all the runs.
 TEST_F(TextureUploadPerfTest, glTexImage2d) {
@@ skipping 13 matching lines @@
   }
 
   for (const auto& entry : aggregates) {
     const auto m = entry.second.Divide(kUploadPerfTestRuns);
     m.PrintResult();
   }
 }
 
 }  // namespace
 }  // namespace gpu