Check if drivers support GL_OES_texture_float even with GLES3 context.

GLES3 adds support for Float type but doesn't specify support for
all formats with FLOAT as GL_OES_texture_float
(i.e. LUMINANCE_ALPHA,LUMINANCE and Alpha). Hence, we need to
explicitly check for support of this extension even with GLES3.

Review URL: https://codereview.chromium.org/696603002

Cr-Commit-Position: refs/heads/master@{#303391}

2 files changed, 27 insertions, 1 deletions

diff --git a/gpu/command_buffer/service/feature_info.cc b/gpu/command_buffer/service/feature_info.cc
index 9be747d..24e1f92 100644
--- a/gpu/command_buffer/service/feature_info.cc
+++ b/gpu/command_buffer/service/feature_info.cc
@@ -477,16 +477,22 @@ void FeatureInfo::InitializeFeatures() {
     enable_texture_half_float_linear = true;
     may_enable_chromium_color_buffer_float = true;
   } else {
-    if (is_es3 || extensions.Contains("GL_OES_texture_float")) {
+    // GLES3 adds support for Float type by default but it doesn't support all
+    // formats as GL_OES_texture_float(i.e.LUMINANCE_ALPHA,LUMINANCE and Alpha)
+    if (extensions.Contains("GL_OES_texture_float")) {
       enable_texture_float = true;
       if (extensions.Contains("GL_OES_texture_float_linear")) {
         enable_texture_float_linear = true;
       }
+      // This extension allows a variety of floating point formats to be
+      // rendered to via framebuffer objects. Enable it's usage only if
+      // support for Floating textures is enabled.
       if ((is_es3 && extensions.Contains("GL_EXT_color_buffer_float")) ||
           feature_flags_.is_angle) {
         may_enable_chromium_color_buffer_float = true;
       }
     }
+
     // TODO(dshwang): GLES3 supports half float by default but GL_HALF_FLOAT_OES
     // isn't equal to GL_HALF_FLOAT.
     if (extensions.Contains("GL_OES_texture_half_float")) {
diff --git a/gpu/command_buffer/service/feature_info_unittest.cc b/gpu/command_buffer/service/feature_info_unittest.cc
index 69bd4d3..88a0a37 100644
--- a/gpu/command_buffer/service/feature_info_unittest.cc
+++ b/gpu/command_buffer/service/feature_info_unittest.cc
@@ -669,6 +669,26 @@ TEST_F(FeatureInfoTest, InitializeARB_texture_float) {
       GL_RGB32F));
 }
 
+TEST_F(FeatureInfoTest, Initialize_texture_floatGLES3) {
+  SetupInitExpectationsWithGLVersion("", "", "OpenGL ES 3.0");
+  EXPECT_THAT(info_->extensions(), Not(HasSubstr("GL_OES_texture_float")));
+  EXPECT_THAT(info_->extensions(), Not(HasSubstr("GL_OES_texture_half_float")));
+  EXPECT_THAT(info_->extensions(),
+              Not(HasSubstr("GL_OES_texture_float_linear")));
+  EXPECT_THAT(info_->extensions(),
+              Not(HasSubstr("GL_OES_texture_half_float_linear")));
+  EXPECT_FALSE(info_->GetTextureFormatValidator(GL_RGB).IsValid(
+      GL_FLOAT));
+  EXPECT_FALSE(info_->GetTextureFormatValidator(GL_RGBA).IsValid(
+      GL_FLOAT));
+  EXPECT_FALSE(info_->GetTextureFormatValidator(GL_LUMINANCE).IsValid(
+      GL_FLOAT));
+  EXPECT_FALSE(info_->GetTextureFormatValidator(GL_LUMINANCE_ALPHA).IsValid(
+      GL_FLOAT));
+  EXPECT_FALSE(info_->GetTextureFormatValidator(GL_ALPHA).IsValid(
+      GL_FLOAT));
+}
+
 TEST_F(FeatureInfoTest, InitializeOES_texture_floatGLES2) {
   SetupInitExpectations("GL_OES_texture_float");
   EXPECT_FALSE(info_->feature_flags().enable_texture_float_linear);