import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/canvas/WebGLExtensionColorBufferFloat.cpp

@@ -0,0 +1,57 @@
+/* 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"
+
+#ifdef FOO
+#error FOO is already defined! We use FOO() macros to keep things succinct in this file.
+#endif
+
+namespace mozilla {
+
+WebGLExtensionColorBufferFloat::WebGLExtensionColorBufferFloat(WebGLContext* webgl)
+    : WebGLExtensionBase(webgl)
+{
+    MOZ_ASSERT(IsSupported(webgl), "Don't construct extension if unsupported.");
+
+    auto& fua = webgl->mFormatUsage;
+
+    auto fnUpdateUsage = [&fua](GLenum sizedFormat, webgl::EffectiveFormat effFormat) {
+        auto usage = fua->EditUsage(effFormat);
+        usage->SetRenderable();
+        fua->AllowRBFormat(sizedFormat, usage);
+    };
+
+#define FOO(x) fnUpdateUsage(LOCAL_GL_ ## x, webgl::EffectiveFormat::x)
+
+    // The extension doesn't actually add RGB32F; only RGBA32F.
+    FOO(RGBA32F);
+
+#undef FOO
+}
+
+WebGLExtensionColorBufferFloat::~WebGLExtensionColorBufferFloat()
+{
+}
+
+bool
+WebGLExtensionColorBufferFloat::IsSupported(const WebGLContext* webgl)
+{
+    gl::GLContext* gl = webgl->GL();
+
+    // ANGLE supports this, but doesn't have a way to advertize its support,
+    // since it's compliant with WEBGL_color_buffer_float's clamping, but not
+    // EXT_color_buffer_float.
+    return gl->IsSupported(gl::GLFeature::renderbuffer_color_float) ||
+           gl->IsANGLE();
+}
+
+IMPL_WEBGL_EXTENSION_GOOP(WebGLExtensionColorBufferFloat, WEBGL_color_buffer_float)
+
+} // namespace mozilla