1 files changed, 51 insertions, 0 deletions
diff --git a/dom/canvas/WebGLExtensionDepthTexture.cpp b/dom/canvas/WebGLExtensionDepthTexture.cpp
new file mode 100644
index 0000000000..f2ef06caf5
--- /dev/null
+++ b/dom/canvas/WebGLExtensionDepthTexture.cpp
@@ -0,0 +1,51 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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"
+
+namespace mozilla {
+
+WebGLExtensionDepthTexture::WebGLExtensionDepthTexture(
+    WebGLContext* const webgl)
+    : WebGLExtensionBase(webgl) {
+  auto& fua = webgl->mFormatUsage;
+
+  const auto fnAdd = [&fua](webgl::EffectiveFormat effFormat,
+                            GLenum unpackFormat, GLenum unpackType) {
+    auto usage = fua->EditUsage(effFormat);
+    MOZ_ASSERT(usage->isFilterable);
+    MOZ_ASSERT(usage->IsRenderable());
+
+    const webgl::PackingInfo pi = {unpackFormat, unpackType};
+    const webgl::DriverUnpackInfo dui = {unpackFormat, unpackFormat,
+                                         unpackType};
+    fua->AddTexUnpack(usage, pi, dui);
+    fua->AllowUnsizedTexFormat(pi, usage);
+  };
+
+  fnAdd(webgl::EffectiveFormat::DEPTH_COMPONENT16, LOCAL_GL_DEPTH_COMPONENT,
+        LOCAL_GL_UNSIGNED_SHORT);
+  fnAdd(webgl::EffectiveFormat::DEPTH_COMPONENT24, LOCAL_GL_DEPTH_COMPONENT,
+        LOCAL_GL_UNSIGNED_INT);
+  fnAdd(webgl::EffectiveFormat::DEPTH24_STENCIL8, LOCAL_GL_DEPTH_STENCIL,
+        LOCAL_GL_UNSIGNED_INT_24_8);
+}
+
+bool WebGLExtensionDepthTexture::IsSupported(const WebGLContext* const webgl) {
+  if (webgl->IsWebGL2()) return false;
+
+  // WEBGL_depth_texture supports DEPTH_STENCIL textures
+  const auto& gl = webgl->gl;
+  if (!gl->IsSupported(gl::GLFeature::packed_depth_stencil)) return false;
+
+  return gl->IsSupported(gl::GLFeature::depth_texture) ||
+         gl->IsExtensionSupported(gl::GLContext::ANGLE_depth_texture);
+}
+
+}  // namespace mozilla