1 files changed, 51 insertions, 0 deletions
diff --git a/dom/canvas/WebGLExtensionCompressedTextureS3TC.cpp b/dom/canvas/WebGLExtensionCompressedTextureS3TC.cpp
new file mode 100644
index 0000000000..35e87bed2a
--- /dev/null
+++ b/dom/canvas/WebGLExtensionCompressedTextureS3TC.cpp
@@ -0,0 +1,51 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "WebGLExtensions.h"
+
+#include "GLContext.h"
+#include "mozilla/dom/WebGLRenderingContextBinding.h"
+#include "WebGLContext.h"
+#include "WebGLFormats.h"
+
+namespace mozilla {
+
+WebGLExtensionCompressedTextureS3TC::WebGLExtensionCompressedTextureS3TC(
+    WebGLContext* webgl)
+    : WebGLExtensionBase(webgl) {
+  RefPtr<WebGLContext> webgl_ = webgl;  // Bug 1201275
+  const auto fnAdd = [&webgl_](GLenum sizedFormat,
+                               webgl::EffectiveFormat effFormat) {
+    auto& fua = webgl_->mFormatUsage;
+
+    auto usage = fua->EditUsage(effFormat);
+    usage->isFilterable = true;
+    fua->AllowSizedTexFormat(sizedFormat, usage);
+  };
+
+#define FOO(x) LOCAL_GL_##x, webgl::EffectiveFormat::x
+
+  fnAdd(FOO(COMPRESSED_RGB_S3TC_DXT1_EXT));
+  fnAdd(FOO(COMPRESSED_RGBA_S3TC_DXT1_EXT));
+  fnAdd(FOO(COMPRESSED_RGBA_S3TC_DXT3_EXT));
+  fnAdd(FOO(COMPRESSED_RGBA_S3TC_DXT5_EXT));
+
+#undef FOO
+}
+
+bool WebGLExtensionCompressedTextureS3TC::IsSupported(
+    const WebGLContext* webgl) {
+  gl::GLContext* gl = webgl->GL();
+  if (gl->IsExtensionSupported(gl::GLContext::EXT_texture_compression_s3tc))
+    return true;
+
+  return gl->IsExtensionSupported(
+             gl::GLContext::EXT_texture_compression_dxt1) &&
+         gl->IsExtensionSupported(
+             gl::GLContext::ANGLE_texture_compression_dxt3) &&
+         gl->IsExtensionSupported(
+             gl::GLContext::ANGLE_texture_compression_dxt5);
+}
+
+}  // namespace mozilla