gpu: support immutable texture on Linux Mesa driver and GLES3.

Mesa GL driver supports GL_ARB_texture_storage extensions, not
GL_EXT_texture_storage. GLES3 supports glTexStroage2D by default.

GLES3 doesn't support BGRA format for immutable texture without
GL_APPLE_texture_format_bgra8888 extension. We prefer BGRA support
to immutable texture support, so GLES3 enables immutable texture
only if it supports GL_APPLE_texture_format_bgra8888.

In addition, currently the compositor blindly uses BGRA on glTexStorage2D.
It can cause a potential bug so this CL checks BGRA format support
to use BGRA on glTexStorage2D.

This CL makes Intel GPU (e.g. Intel Chromebook) and GLES3 devices with
GL_APPLE_texture_format_bgra8888 extension take advantage of immutable
texture.

BUG=407034

Review URL: https://codereview.chromium.org/499283002

Cr-Commit-Position: refs/heads/master@{#292175}

2 files changed, 196 insertions, 2 deletions

diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index de3eb56..968f2e4 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -396,10 +396,12 @@ void FeatureInfo::InitializeFeatures() {
   bool enable_texture_format_bgra8888 = false;
   bool enable_read_format_bgra = false;
   bool enable_render_buffer_bgra = false;
+  bool enable_immutable_texture_format_bgra_on_es3 =
+      extensions.Contains("GL_APPLE_texture_format_BGRA8888");
 
   // Check if we should allow GL_EXT_texture_format_BGRA8888
   if (extensions.Contains("GL_EXT_texture_format_BGRA8888") ||
-      extensions.Contains("GL_APPLE_texture_format_BGRA8888") ||
+      enable_immutable_texture_format_bgra_on_es3 ||
       extensions.Contains("GL_EXT_bgra")) {
     enable_texture_format_bgra8888 = true;
   }
@@ -692,7 +694,18 @@ void FeatureInfo::InitializeFeatures() {
     validators_.texture_parameter.AddValue(GL_TEXTURE_USAGE_ANGLE);
   }
 
-  if (extensions.Contains("GL_EXT_texture_storage")) {
+  // Note: Only APPLE_texture_format_BGRA8888 extension allows BGRA8_EXT in
+  // ES3's glTexStorage2D. We prefer support BGRA to texture storage.
+  // So we don't expose GL_EXT_texture_storage when ES3 +
+  // GL_EXT_texture_format_BGRA8888 because we fail the GL_BGRA8 requirement.
+  // However we expose GL_EXT_texture_storage when just ES3 because we don't
+  // claim to handle GL_BGRA8.
+  bool support_texture_storage_on_es3 =
+      (is_es3 && enable_immutable_texture_format_bgra_on_es3) ||
+      (is_es3 && !enable_texture_format_bgra8888);
+  if (extensions.Contains("GL_EXT_texture_storage") ||
+      extensions.Contains("GL_ARB_texture_storage") ||
+      support_texture_storage_on_es3) {
     feature_flags_.ext_texture_storage = true;
     AddExtensionString("GL_EXT_texture_storage");
     validators_.texture_parameter.AddValue(GL_TEXTURE_IMMUTABLE_FORMAT_EXT);
diff --git a/gpu/command_buffer/service/feature_info_unittest.cc b/gpu/command_buffer/service/feature_info_unittest.cc
index 1010f99..6e2cb46 100644
--- a/gpu/command_buffer/service/feature_info_unittest.cc
+++ b/gpu/command_buffer/service/feature_info_unittest.cc
@@ -433,6 +433,187 @@ TEST_F(FeatureInfoTest, InitializeEXT_read_format_bgra) {
       GL_BGRA8_EXT));
 }
 
+TEST_F(FeatureInfoTest, InitializeEXT_texture_storage) {
+  SetupInitExpectations("GL_EXT_texture_storage");
+  EXPECT_TRUE(info_->feature_flags().ext_texture_storage);
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_TRUE(info_->validators()->texture_parameter.IsValid(
+      GL_TEXTURE_IMMUTABLE_FORMAT_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_BGRA8_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGBA32F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGB32F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_ALPHA32F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE32F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE_ALPHA32F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGBA16F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGB16F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_ALPHA16F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE16F_EXT));
+  EXPECT_FALSE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE_ALPHA16F_EXT));
+}
+
+TEST_F(FeatureInfoTest, InitializeARB_texture_storage) {
+  SetupInitExpectations("GL_ARB_texture_storage");
+  EXPECT_TRUE(info_->feature_flags().ext_texture_storage);
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_TRUE(info_->validators()->texture_parameter.IsValid(
+      GL_TEXTURE_IMMUTABLE_FORMAT_EXT));
+}
+
+TEST_F(FeatureInfoTest, InitializeEXT_texture_storage_BGRA) {
+  SetupInitExpectations("GL_EXT_texture_storage GL_EXT_bgra");
+  EXPECT_TRUE(info_->feature_flags().ext_texture_storage);
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_BGRA8_EXT));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+TEST_F(FeatureInfoTest, InitializeARB_texture_storage_BGRA) {
+  SetupInitExpectations("GL_ARB_texture_storage GL_EXT_bgra");
+  EXPECT_TRUE(info_->feature_flags().ext_texture_storage);
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_BGRA8_EXT));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+TEST_F(FeatureInfoTest, InitializeEXT_texture_storage_BGRA8888) {
+  SetupInitExpectations(
+      "GL_EXT_texture_storage GL_EXT_texture_format_BGRA8888");
+  EXPECT_TRUE(info_->feature_flags().ext_texture_storage);
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_BGRA8_EXT));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+TEST_F(FeatureInfoTest, InitializeEXT_texture_storage_float) {
+  SetupInitExpectations("GL_EXT_texture_storage GL_OES_texture_float");
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_OES_texture_float"));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGBA32F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGB32F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_ALPHA32F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE32F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE_ALPHA32F_EXT));
+}
+
+TEST_F(FeatureInfoTest, InitializeEXT_texture_storage_half_float) {
+  SetupInitExpectations("GL_EXT_texture_storage GL_OES_texture_half_float");
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_OES_texture_half_float"));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGBA16F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_RGB16F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_ALPHA16F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE16F_EXT));
+  EXPECT_TRUE(info_->validators()->texture_internal_format_storage.IsValid(
+      GL_LUMINANCE_ALPHA16F_EXT));
+}
+
+// Check how to handle ES, texture_storage and BGRA combination; 8 tests.
+
+// 1- ES2 + GL_EXT_texture_storage -> GL_EXT_texture_storage (and no
+// GL_EXT_texture_format_BGRA8888 - we don't claim to handle GL_BGRA8 in
+// glTexStorage2DEXT)
+TEST_F(FeatureInfoTest, InitializeGLES2_texture_storage) {
+  SetupInitExpectationsWithGLVersion(
+      "GL_EXT_texture_storage", "", "OpenGL ES 2.0");
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(),
+              Not(HasSubstr("GL_EXT_texture_format_BGRA8888")));
+}
+
+// 2- ES2 + GL_EXT_texture_storage + (GL_EXT_texture_format_BGRA8888 or
+// GL_APPLE_texture_format_bgra8888)
+TEST_F(FeatureInfoTest, InitializeGLES2_texture_storage_BGRA) {
+  SetupInitExpectationsWithGLVersion(
+      "GL_EXT_texture_storage GL_EXT_texture_format_BGRA8888",
+      "",
+      "OpenGL ES 2.0");
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+// 3- ES2 + GL_EXT_texture_format_BGRA8888 or GL_APPLE_texture_format_bgra8888
+TEST_F(FeatureInfoTest, InitializeGLES2_texture_format_BGRA) {
+  SetupInitExpectationsWithGLVersion(
+      "GL_EXT_texture_format_BGRA8888", "", "OpenGL ES 2.0");
+  EXPECT_THAT(info_->extensions(), Not(HasSubstr("GL_EXT_texture_storage")));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+// 4- ES2 (neither GL_EXT_texture_storage nor GL_EXT_texture_format_BGRA8888) ->
+// nothing
+TEST_F(FeatureInfoTest, InitializeGLES2_neither_texture_storage_nor_BGRA) {
+  SetupInitExpectationsWithGLVersion("", "", "OpenGL ES 2.0");
+  EXPECT_THAT(info_->extensions(), Not(HasSubstr("GL_EXT_texture_storage")));
+  EXPECT_THAT(info_->extensions(),
+              Not(HasSubstr("GL_EXT_texture_format_BGRA8888")));
+}
+
+// 5- ES3 + GL_EXT_texture_format_BGRA8888 -> GL_EXT_texture_format_BGRA8888
+// (we can't expose GL_EXT_texture_storage because we fail the GL_BGRA8
+// requirement)
+TEST_F(FeatureInfoTest, InitializeGLES3_texture_storage_EXT_BGRA) {
+  SetupInitExpectationsWithGLVersion(
+      "GL_EXT_texture_format_BGRA8888", "", "OpenGL ES 3.0");
+  EXPECT_THAT(info_->extensions(), Not(HasSubstr("GL_EXT_texture_storage")));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+// 6- ES3 + GL_APPLE_texture_format_bgra8888 -> GL_EXT_texture_storage +
+// GL_EXT_texture_format_BGRA8888 (driver promises to handle GL_BGRA8 by
+// exposing GL_APPLE_texture_format_bgra8888)
+TEST_F(FeatureInfoTest, InitializeGLES3_texture_storage_APPLE_BGRA) {
+  SetupInitExpectationsWithGLVersion(
+      "GL_APPLE_texture_format_BGRA8888", "", "OpenGL ES 3.0");
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+// 7- ES3 + GL_EXT_texture_storage + GL_EXT_texture_format_BGRA8888 ->
+// GL_EXT_texture_storage + GL_EXT_texture_format_BGRA8888  (driver promises to
+// handle GL_BGRA8 by exposing GL_EXT_texture_storage)
+TEST_F(FeatureInfoTest, InitializeGLES3_EXT_texture_storage_EXT_BGRA) {
+  SetupInitExpectationsWithGLVersion(
+      "GL_EXT_texture_storage GL_EXT_texture_format_BGRA8888",
+      "",
+      "OpenGL ES 3.0");
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_format_BGRA8888"));
+}
+
+// 8- ES3 + none of the above -> GL_EXT_texture_storage (and no
+// GL_EXT_texture_format_BGRA8888 - we don't claim to handle GL_BGRA8)
+TEST_F(FeatureInfoTest, InitializeGLES3_texture_storage) {
+  SetupInitExpectationsWithGLVersion("", "", "OpenGL ES 3.0");
+  EXPECT_THAT(info_->extensions(), HasSubstr("GL_EXT_texture_storage"));
+  EXPECT_THAT(info_->extensions(),
+              Not(HasSubstr("GL_EXT_texture_format_BGRA8888")));
+}
+
 TEST_F(FeatureInfoTest, InitializeARB_texture_float) {
   SetupInitExpectations("GL_ARB_texture_float");
   EXPECT_TRUE(info_->feature_flags().chromium_color_buffer_float_rgba);