gpu: workaround force_cube_map_positive_x_allocation fixes Android crash.

gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc

Index: gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc
diff --git a/gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc b/gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..2f052ac4e9fbf88d39afc691e3ffe2558e73f87b
--- /dev/null
+++ b/gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc
@@ -0,0 +1,138 @@
+// 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 <GLES2/gl2.h>
+
+#include "gpu/command_buffer/tests/gl_manager.h"
+#include "gpu/command_buffer/tests/gl_test_utils.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace gpu {
+
+namespace {
+const GLenum kCubeMapTextureTargets[] = {
+    GL_TEXTURE_CUBE_MAP_POSITIVE_X, GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
+    GL_TEXTURE_CUBE_MAP_POSITIVE_Y, GL_TEXTURE_CUBE_MAP_NEGATIVE_Y,
+    GL_TEXTURE_CUBE_MAP_POSITIVE_Z, GL_TEXTURE_CUBE_MAP_NEGATIVE_Z,
+};
+}  // namespace
+
+// A collection of tests that exercise the cube map texture.
+class GLCubeMapTextureTest : public testing::TestWithParam<GLenum> {
+ protected:
+  void SetUp() override {
+    gl_.Initialize(GLManager::Options());
+    for (int i = 0; i < 256; i++) {
+      pixels_[i * 4] = 255u;
+      pixels_[(i * 4) + 1] = 0;
+      pixels_[(i * 4) + 2] = 0;
+      pixels_[(i * 4) + 3] = 255u;
+    }
+
+    glGenTextures(1, &texture_);
+    glBindTexture(GL_TEXTURE_CUBE_MAP, texture_);
+    EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+
+    glTexParameterf(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameterf(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+
+    glGenFramebuffers(1, &framebuffer_id_);
+  }
+
+  void TearDown() override {
+    glDeleteTextures(1, &texture_);
+    glDeleteFramebuffers(1, &framebuffer_id_);
+    gl_.Destroy();
+  }
+
+  GLManager gl_;
+  uint8 pixels_[256 * 4];
+  const int width_ = 16;
+  GLuint texture_;
+  GLuint framebuffer_id_;
+};
+
+INSTANTIATE_TEST_CASE_P(GLCubeMapTextureTests,
+                        GLCubeMapTextureTest,
+                        ::testing::ValuesIn(kCubeMapTextureTargets));
+
+TEST_P(GLCubeMapTextureTest, TexImage2DAfterFBOBinding) {
+  GLenum cube_map_target = GetParam();
+
+  glBindFramebuffer(GL_FRAMEBUFFER, framebuffer_id_);
+  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, cube_map_target,
+                         texture_, 0);
+  EXPECT_TRUE(glGetError() == GL_NO_ERROR);

[no sievers, 2015/08/13 18:56:38]

nit: EXPECT_EQ(static_cast<GLenum>(GL_NO_ERROR), glGetError())
here and everywhere below

[dshwang, 2015/08/14 06:22:56]

Done.

+
+  glBindTexture(GL_TEXTURE_CUBE_MAP, texture_);
+  // force_gl_finish_after_compositing workaround prevents Nexus 5 crash.
+  // TODO(dshwang): remove the workaround when it's fixed. crbug.com/518889
+  glTexImage2D(cube_map_target, 0, GL_RGBA, width_, width_, 0, GL_RGBA,
+               GL_UNSIGNED_BYTE, pixels_);
+  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+}
+
+TEST_P(GLCubeMapTextureTest, ReadPixels) {
+  GLenum cube_map_target = GetParam();
+
+  glBindTexture(GL_TEXTURE_CUBE_MAP, texture_);
+  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+
+  // Make a cube texture complete
+  for (unsigned i = 0; i < arraysize(kCubeMapTextureTargets); i++) {
+    glTexImage2D(kCubeMapTextureTargets[i], 0, GL_RGBA, width_, width_, 0,
+                 GL_RGBA, GL_UNSIGNED_BYTE, pixels_);
+    EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+  }
+
+  glBindFramebuffer(GL_FRAMEBUFFER, framebuffer_id_);
+  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, cube_map_target,
+                         texture_, 0);
+  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+
+  // Check that FB is complete.
+  EXPECT_EQ(static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE),
+            glCheckFramebufferStatus(GL_FRAMEBUFFER));
+
+  GLTestHelper::CheckPixels(0, 0, width_, width_, 0, pixels_);
+  EXPECT_TRUE(GL_NO_ERROR == glGetError());
+}
+
+#if defined(OS_WIN)
+// TODO(dshwang): ANGLE crashes. crbug.com/518889
+TEST_P(GLCubeMapTextureTest, DISABLED_ReadPixelsFromIncompleteFBO) {
+#else
+TEST_P(GLCubeMapTextureTest, ReadPixelsFromIncompleteFBO) {
+#endif
+  GLenum cube_map_target = GetParam();
+
+  glBindTexture(GL_TEXTURE_CUBE_MAP, texture_);
+  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+
+  glTexImage2D(cube_map_target, 0, GL_RGBA, width_, width_, 0, GL_RGBA,
+               GL_UNSIGNED_BYTE, pixels_);
+  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+
+  glBindFramebuffer(GL_FRAMEBUFFER, framebuffer_id_);
+  glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, cube_map_target,
+                         texture_, 0);
+
+  // force_gl_finish_after_compositing workaround prevents Nexus 5 crash.
+  // TODO(dshwang): remove the workaround when it's fixed. crbug.com/518889
+  EXPECT_TRUE(glGetError() == GL_NO_ERROR);
+
+  GLsizei size = width_ * width_ * 4;
+  scoped_ptr<uint8[]> pixels(new uint8[size]);
+  // ANGLE crashes on glReadPixels() from incomplete FBO.
+  glReadPixels(0, 0, width_, width_, GL_RGBA, GL_UNSIGNED_BYTE, pixels.get());
+  // According to spec, above glReadPixels() should fail and glGetError()

[no sievers, 2015/08/13 18:56:38]

Sorry for missing this earlier, but on second thought I'm confused: isn't
framebuffer completeness something we already check in HandleReadPixels()? (see
CheckBoundFramebuffersValid call.) Either way I'm wondering if this isn't
something we should catch so the behavior is consistent.

[dshwang, 2015/08/14 06:22:56]

HandleReadPixels() already check FBO completeness, but doesn't check cube
complete.
I submitted another CL to fix it; https://codereview.chromium.org/1283303002/

+  // should report an error, but some drivers are fine to bind incomplete cube
+  // map texture to FBO.
+  glGetError();
+}
+
+}  // namespace gpu