Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 565 insertions, 0 deletions

diff --git a/dom/canvas/WebGLContextExtensions.cpp b/dom/canvas/WebGLContextExtensions.cpp
new file mode 100644
index 0000000000..70548e62dc
--- /dev/null
+++ b/dom/canvas/WebGLContextExtensions.cpp
@@ -0,0 +1,565 @@
+/* -*- Mode: C++; tab-width: 4; 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 "WebGLContext.h"
+#include "ClientWebGLExtensions.h"
+#include "GLContext.h"
+#include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/dom/ToJSValue.h"
+#include "mozilla/EnumeratedRange.h"
+#include "mozilla/StaticPrefs_webgl.h"
+#include "nsString.h"
+#include "WebGLContextUtils.h"
+#include "WebGLExtensions.h"
+
+namespace mozilla {
+
+const char* GetExtensionName(const WebGLExtensionID ext) {
+  static EnumeratedArray<WebGLExtensionID, WebGLExtensionID::Max, const char*>
+      sExtensionNamesEnumeratedArray;
+  static bool initialized = false;
+
+  if (!initialized) {
+    initialized = true;
+
+#define WEBGL_EXTENSION_IDENTIFIER(x) \
+  sExtensionNamesEnumeratedArray[WebGLExtensionID::x] = #x;
+
+    WEBGL_EXTENSION_IDENTIFIER(ANGLE_instanced_arrays)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_blend_minmax)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_color_buffer_float)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_color_buffer_half_float)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_disjoint_timer_query)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_float_blend)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_frag_depth)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_shader_texture_lod)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_sRGB)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_texture_compression_bptc)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_texture_compression_rgtc)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_texture_filter_anisotropic)
+    WEBGL_EXTENSION_IDENTIFIER(EXT_texture_norm16)
+    WEBGL_EXTENSION_IDENTIFIER(MOZ_debug)
+    WEBGL_EXTENSION_IDENTIFIER(OES_draw_buffers_indexed)
+    WEBGL_EXTENSION_IDENTIFIER(OES_element_index_uint)
+    WEBGL_EXTENSION_IDENTIFIER(OES_fbo_render_mipmap)
+    WEBGL_EXTENSION_IDENTIFIER(OES_standard_derivatives)
+    WEBGL_EXTENSION_IDENTIFIER(OES_texture_float)
+    WEBGL_EXTENSION_IDENTIFIER(OES_texture_float_linear)
+    WEBGL_EXTENSION_IDENTIFIER(OES_texture_half_float)
+    WEBGL_EXTENSION_IDENTIFIER(OES_texture_half_float_linear)
+    WEBGL_EXTENSION_IDENTIFIER(OES_vertex_array_object)
+    WEBGL_EXTENSION_IDENTIFIER(OVR_multiview2)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_color_buffer_float)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_astc)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_etc)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_etc1)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_pvrtc)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_s3tc)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_compressed_texture_s3tc_srgb)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_debug_renderer_info)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_debug_shaders)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_depth_texture)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_draw_buffers)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_explicit_present)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_lose_context)
+    WEBGL_EXTENSION_IDENTIFIER(WEBGL_provoking_vertex)
+
+#undef WEBGL_EXTENSION_IDENTIFIER
+  }
+
+  return sExtensionNamesEnumeratedArray[ext];
+}
+
+// ----------------------------
+// ClientWebGLContext
+
+void ClientWebGLContext::GetExtension(JSContext* cx, const nsAString& wideName,
+                                      JS::MutableHandle<JSObject*> retval,
+                                      dom::CallerType callerType,
+                                      ErrorResult& rv) {
+  retval.set(nullptr);
+  const FuncScope funcScope(*this, "getExtension");
+  if (IsContextLost()) return;
+
+  const auto name = NS_ConvertUTF16toUTF8(wideName);
+
+  auto ext = WebGLExtensionID::Max;
+
+  // step 1: figure what extension is wanted
+  for (const auto extension : MakeEnumeratedRange(WebGLExtensionID::Max)) {
+    const auto& curName = GetExtensionName(extension);
+    if (name.Equals(curName, nsCaseInsensitiveCStringComparator)) {
+      ext = extension;
+      break;
+    }
+  }
+
+  if (ext == WebGLExtensionID::Max) return;
+
+  RefPtr<ClientWebGLExtensionBase> extObj;
+  if (ext == WebGLExtensionID::WEBGL_lose_context) {
+    extObj = mExtLoseContext;
+  } else {
+    extObj = GetExtension(ext, callerType);
+  }
+  if (!extObj) return;
+
+  // Ugh, this would be easier returning `any` than `object`.
+  JS::Rooted<JS::Value> v(cx);
+  MOZ_ALWAYS_TRUE(dom::ToJSValue(cx, extObj, &v));
+  if (v.isObject()) {
+    retval.set(&v.toObject());
+  }
+}
+
+RefPtr<ClientWebGLExtensionBase> ClientWebGLContext::GetExtension(
+    const WebGLExtensionID ext, const dom::CallerType callerType) {
+  if (ext == WebGLExtensionID::WEBGL_lose_context) {
+    // Always the same.
+    return mExtLoseContext;
+  }
+
+  if (!mNotLost) return nullptr;
+
+  if (!IsSupported(ext, callerType)) return nullptr;
+
+  auto& extSlot = mNotLost->extensions[UnderlyingValue(ext)];
+  if (MOZ_UNLIKELY(!extSlot)) {
+    extSlot = [&]() -> RefPtr<ClientWebGLExtensionBase> {
+      switch (ext) {
+        // ANGLE_
+        case WebGLExtensionID::ANGLE_instanced_arrays:
+          return new ClientWebGLExtensionInstancedArrays(*this);
+
+        // EXT_
+        case WebGLExtensionID::EXT_blend_minmax:
+          return new ClientWebGLExtensionBlendMinMax(*this);
+        case WebGLExtensionID::EXT_color_buffer_float:
+          return new ClientWebGLExtensionEXTColorBufferFloat(*this);
+        case WebGLExtensionID::EXT_color_buffer_half_float:
+          return new ClientWebGLExtensionColorBufferHalfFloat(*this);
+        case WebGLExtensionID::EXT_disjoint_timer_query:
+          return new ClientWebGLExtensionDisjointTimerQuery(*this);
+        case WebGLExtensionID::EXT_float_blend:
+          return new ClientWebGLExtensionFloatBlend(*this);
+        case WebGLExtensionID::EXT_frag_depth:
+          return new ClientWebGLExtensionFragDepth(*this);
+        case WebGLExtensionID::EXT_shader_texture_lod:
+          return new ClientWebGLExtensionShaderTextureLod(*this);
+        case WebGLExtensionID::EXT_sRGB:
+          return new ClientWebGLExtensionSRGB(*this);
+        case WebGLExtensionID::EXT_texture_compression_bptc:
+          return new ClientWebGLExtensionCompressedTextureBPTC(*this);
+        case WebGLExtensionID::EXT_texture_compression_rgtc:
+          return new ClientWebGLExtensionCompressedTextureRGTC(*this);
+        case WebGLExtensionID::EXT_texture_filter_anisotropic:
+          return new ClientWebGLExtensionTextureFilterAnisotropic(*this);
+        case WebGLExtensionID::EXT_texture_norm16:
+          return new ClientWebGLExtensionTextureNorm16(*this);
+
+        // MOZ_
+        case WebGLExtensionID::MOZ_debug:
+          return new ClientWebGLExtensionMOZDebug(*this);
+
+        // OES_
+        case WebGLExtensionID::OES_draw_buffers_indexed:
+          return new ClientWebGLExtensionDrawBuffersIndexed(*this);
+        case WebGLExtensionID::OES_element_index_uint:
+          return new ClientWebGLExtensionElementIndexUint(*this);
+        case WebGLExtensionID::OES_fbo_render_mipmap:
+          return new ClientWebGLExtensionFBORenderMipmap(*this);
+        case WebGLExtensionID::OES_standard_derivatives:
+          return new ClientWebGLExtensionStandardDerivatives(*this);
+        case WebGLExtensionID::OES_texture_float:
+          return new ClientWebGLExtensionTextureFloat(*this);
+        case WebGLExtensionID::OES_texture_float_linear:
+          return new ClientWebGLExtensionTextureFloatLinear(*this);
+        case WebGLExtensionID::OES_texture_half_float:
+          return new ClientWebGLExtensionTextureHalfFloat(*this);
+        case WebGLExtensionID::OES_texture_half_float_linear:
+          return new ClientWebGLExtensionTextureHalfFloatLinear(*this);
+        case WebGLExtensionID::OES_vertex_array_object:
+          return new ClientWebGLExtensionVertexArray(*this);
+
+        // OVR_
+        case WebGLExtensionID::OVR_multiview2:
+          return new ClientWebGLExtensionMultiview(*this);
+
+        // WEBGL_
+        case WebGLExtensionID::WEBGL_color_buffer_float:
+          return new ClientWebGLExtensionColorBufferFloat(*this);
+        case WebGLExtensionID::WEBGL_compressed_texture_astc:
+          return new ClientWebGLExtensionCompressedTextureASTC(*this);
+        case WebGLExtensionID::WEBGL_compressed_texture_etc:
+          return new ClientWebGLExtensionCompressedTextureES3(*this);
+        case WebGLExtensionID::WEBGL_compressed_texture_etc1:
+          return new ClientWebGLExtensionCompressedTextureETC1(*this);
+        case WebGLExtensionID::WEBGL_compressed_texture_pvrtc:
+          return new ClientWebGLExtensionCompressedTexturePVRTC(*this);
+        case WebGLExtensionID::WEBGL_compressed_texture_s3tc:
+          return new ClientWebGLExtensionCompressedTextureS3TC(*this);
+        case WebGLExtensionID::WEBGL_compressed_texture_s3tc_srgb:
+          return new ClientWebGLExtensionCompressedTextureS3TC_SRGB(*this);
+        case WebGLExtensionID::WEBGL_debug_renderer_info: {
+          if (callerType != dom::CallerType::System) {
+            JsWarning(
+                "WEBGL_debug_renderer_info is deprecated in Firefox and will "
+                "be removed. Please use RENDERER.");
+          }
+          return new ClientWebGLExtensionDebugRendererInfo(*this);
+        }
+        case WebGLExtensionID::WEBGL_debug_shaders:
+          return new ClientWebGLExtensionDebugShaders(*this);
+        case WebGLExtensionID::WEBGL_depth_texture:
+          return new ClientWebGLExtensionDepthTexture(*this);
+        case WebGLExtensionID::WEBGL_draw_buffers:
+          return new ClientWebGLExtensionDrawBuffers(*this);
+        case WebGLExtensionID::WEBGL_explicit_present:
+          return new ClientWebGLExtensionExplicitPresent(*this);
+        case WebGLExtensionID::WEBGL_provoking_vertex:
+          return new ClientWebGLExtensionProvokingVertex(*this);
+
+        case WebGLExtensionID::WEBGL_lose_context:
+        case WebGLExtensionID::Max:
+          break;
+      }
+      MOZ_CRASH("illegal extension enum");
+    }();
+    MOZ_ASSERT(extSlot);
+    RequestExtension(ext);
+  }
+
+  return extSlot;
+}
+
+// ----------------------------
+// WebGLContext
+
+bool WebGLContext::IsExtensionSupported(WebGLExtensionID ext) const {
+  switch (ext) {
+    case WebGLExtensionID::MOZ_debug:
+    case WebGLExtensionID::WEBGL_debug_renderer_info:
+    case WebGLExtensionID::WEBGL_debug_shaders:
+    case WebGLExtensionID::WEBGL_lose_context:
+      // Always supported.
+      return true;
+
+    // In alphabetical order
+    // ANGLE_
+    case WebGLExtensionID::ANGLE_instanced_arrays:
+      return WebGLExtensionInstancedArrays::IsSupported(this);
+
+    // EXT_
+    case WebGLExtensionID::EXT_blend_minmax:
+      return WebGLExtensionBlendMinMax::IsSupported(this);
+
+    case WebGLExtensionID::EXT_color_buffer_float:
+      return WebGLExtensionEXTColorBufferFloat::IsSupported(this);
+
+    case WebGLExtensionID::EXT_color_buffer_half_float:
+      return WebGLExtensionColorBufferHalfFloat::IsSupported(this);
+
+    case WebGLExtensionID::EXT_disjoint_timer_query:
+      return WebGLExtensionDisjointTimerQuery::IsSupported(this);
+
+    case WebGLExtensionID::EXT_float_blend:
+      return WebGLExtensionFloatBlend::IsSupported(this);
+
+    case WebGLExtensionID::EXT_frag_depth:
+      return WebGLExtensionFragDepth::IsSupported(this);
+
+    case WebGLExtensionID::EXT_shader_texture_lod:
+      return WebGLExtensionShaderTextureLod::IsSupported(this);
+
+    case WebGLExtensionID::EXT_sRGB:
+      return WebGLExtensionSRGB::IsSupported(this);
+
+    case WebGLExtensionID::EXT_texture_compression_bptc:
+      return WebGLExtensionCompressedTextureBPTC::IsSupported(this);
+
+    case WebGLExtensionID::EXT_texture_compression_rgtc:
+      return WebGLExtensionCompressedTextureRGTC::IsSupported(this);
+
+    case WebGLExtensionID::EXT_texture_filter_anisotropic:
+      return gl->IsExtensionSupported(
+          gl::GLContext::EXT_texture_filter_anisotropic);
+
+    case WebGLExtensionID::EXT_texture_norm16:
+      return WebGLExtensionTextureNorm16::IsSupported(this);
+
+    // OES_
+    case WebGLExtensionID::OES_draw_buffers_indexed:
+      if (!IsWebGL2()) return false;
+      return gl->IsSupported(gl::GLFeature::draw_buffers_indexed) &&
+             gl->IsSupported(gl::GLFeature::get_integer_indexed);
+
+    case WebGLExtensionID::OES_element_index_uint:
+      if (IsWebGL2()) return false;
+      return gl->IsSupported(gl::GLFeature::element_index_uint);
+
+    case WebGLExtensionID::OES_fbo_render_mipmap:
+      return WebGLExtensionFBORenderMipmap::IsSupported(this);
+
+    case WebGLExtensionID::OES_standard_derivatives:
+      if (IsWebGL2()) return false;
+      return gl->IsSupported(gl::GLFeature::standard_derivatives);
+
+    case WebGLExtensionID::OES_texture_float:
+      return WebGLExtensionTextureFloat::IsSupported(this);
+
+    case WebGLExtensionID::OES_texture_float_linear:
+      return gl->IsSupported(gl::GLFeature::texture_float_linear);
+
+    case WebGLExtensionID::OES_texture_half_float:
+      return WebGLExtensionTextureHalfFloat::IsSupported(this);
+
+    case WebGLExtensionID::OES_texture_half_float_linear:
+      if (IsWebGL2()) return false;
+      return gl->IsSupported(gl::GLFeature::texture_half_float_linear);
+
+    case WebGLExtensionID::OES_vertex_array_object:
+      return !IsWebGL2();  // Always supported in webgl1.
+
+    // OVR_
+    case WebGLExtensionID::OVR_multiview2:
+      return WebGLExtensionMultiview::IsSupported(this);
+
+    // WEBGL_
+    case WebGLExtensionID::WEBGL_color_buffer_float:
+      return WebGLExtensionColorBufferFloat::IsSupported(this);
+
+    case WebGLExtensionID::WEBGL_compressed_texture_astc:
+      return WebGLExtensionCompressedTextureASTC::IsSupported(this);
+
+    case WebGLExtensionID::WEBGL_compressed_texture_etc:
+      return gl->IsSupported(gl::GLFeature::ES3_compatibility) &&
+             !gl->IsANGLE();
+
+    case WebGLExtensionID::WEBGL_compressed_texture_etc1:
+      return gl->IsExtensionSupported(
+                 gl::GLContext::OES_compressed_ETC1_RGB8_texture) &&
+             !gl->IsANGLE();
+
+    case WebGLExtensionID::WEBGL_compressed_texture_pvrtc:
+      return gl->IsExtensionSupported(
+          gl::GLContext::IMG_texture_compression_pvrtc);
+
+    case WebGLExtensionID::WEBGL_compressed_texture_s3tc:
+      return WebGLExtensionCompressedTextureS3TC::IsSupported(this);
+
+    case WebGLExtensionID::WEBGL_compressed_texture_s3tc_srgb:
+      return WebGLExtensionCompressedTextureS3TC_SRGB::IsSupported(this);
+
+    case WebGLExtensionID::WEBGL_depth_texture:
+      return WebGLExtensionDepthTexture::IsSupported(this);
+
+    case WebGLExtensionID::WEBGL_draw_buffers:
+      return WebGLExtensionDrawBuffers::IsSupported(this);
+
+    case WebGLExtensionID::WEBGL_explicit_present:
+      return WebGLExtensionExplicitPresent::IsSupported(this);
+
+    case WebGLExtensionID::WEBGL_provoking_vertex:
+      if (!gl->IsSupported(gl::GLFeature::provoking_vertex)) return false;
+
+      // > Implementations SHOULD only expose this extension when
+      // > FIRST_VERTEX_CONVENTION is more efficient than the default behavior
+      // > of LAST_VERTEX_CONVENTION.
+      if (gl->IsANGLE()) return true;  // Better on D3D.
+      if (kIsMacOS) {
+        // Better on Metal, so probably Mac in general.
+        return true;
+      }
+      return false;  // Probably not better for Win+GL, Linux, or Android.
+
+    case WebGLExtensionID::Max:
+      break;
+  }
+
+  MOZ_CRASH();
+}
+
+bool WebGLContext::IsExtensionExplicit(const WebGLExtensionID ext) const {
+  return mExtensions[ext] && mExtensions[ext]->IsExplicit();
+}
+
+void WebGLContext::WarnIfImplicit(const WebGLExtensionID ext) const {
+  const auto& extension = mExtensions[ext];
+  if (!extension || extension->IsExplicit()) return;
+
+  GenerateWarning(
+      "Using format enabled by implicitly enabled extension: %s. "
+      "For maximal portability enable it explicitly.",
+      GetExtensionName(ext));
+}
+
+void WebGLContext::RequestExtension(const WebGLExtensionID ext,
+                                    const bool explicitly) {
+  const auto& limits = Limits();
+  if (!limits.supportedExtensions[ext]) return;
+
+  auto& slot = mExtensions[ext];
+  switch (ext) {
+    // ANGLE_
+    case WebGLExtensionID::ANGLE_instanced_arrays:
+      slot.reset(new WebGLExtensionInstancedArrays(this));
+      break;
+
+    // EXT_
+    case WebGLExtensionID::EXT_blend_minmax:
+      slot.reset(new WebGLExtensionBlendMinMax(this));
+      break;
+    case WebGLExtensionID::EXT_color_buffer_float:
+      slot.reset(new WebGLExtensionEXTColorBufferFloat(this));
+      break;
+    case WebGLExtensionID::EXT_color_buffer_half_float:
+      slot.reset(new WebGLExtensionColorBufferHalfFloat(this));
+      break;
+    case WebGLExtensionID::EXT_disjoint_timer_query:
+      slot.reset(new WebGLExtensionDisjointTimerQuery(this));
+      break;
+    case WebGLExtensionID::EXT_float_blend:
+      slot.reset(new WebGLExtensionFloatBlend(this));
+      break;
+    case WebGLExtensionID::EXT_frag_depth:
+      slot.reset(new WebGLExtensionFragDepth(this));
+      break;
+    case WebGLExtensionID::EXT_shader_texture_lod:
+      slot.reset(new WebGLExtensionShaderTextureLod(this));
+      break;
+    case WebGLExtensionID::EXT_sRGB:
+      slot.reset(new WebGLExtensionSRGB(this));
+      break;
+    case WebGLExtensionID::EXT_texture_compression_bptc:
+      slot.reset(new WebGLExtensionCompressedTextureBPTC(this));
+      break;
+    case WebGLExtensionID::EXT_texture_compression_rgtc:
+      slot.reset(new WebGLExtensionCompressedTextureRGTC(this));
+      break;
+    case WebGLExtensionID::EXT_texture_filter_anisotropic:
+      slot.reset(new WebGLExtensionTextureFilterAnisotropic(this));
+      break;
+    case WebGLExtensionID::EXT_texture_norm16:
+      slot.reset(new WebGLExtensionTextureNorm16(this));
+      break;
+
+    // MOZ_
+    case WebGLExtensionID::MOZ_debug:
+      slot.reset(new WebGLExtensionMOZDebug(this));
+      break;
+
+    // OES_
+    case WebGLExtensionID::OES_draw_buffers_indexed:
+      slot.reset(new WebGLExtensionDrawBuffersIndexed(this));
+      break;
+    case WebGLExtensionID::OES_element_index_uint:
+      slot.reset(new WebGLExtensionElementIndexUint(this));
+      break;
+    case WebGLExtensionID::OES_fbo_render_mipmap:
+      slot.reset(new WebGLExtensionFBORenderMipmap(this));
+      break;
+    case WebGLExtensionID::OES_standard_derivatives:
+      slot.reset(new WebGLExtensionStandardDerivatives(this));
+      break;
+    case WebGLExtensionID::OES_texture_float:
+      slot.reset(new WebGLExtensionTextureFloat(this));
+      break;
+    case WebGLExtensionID::OES_texture_float_linear:
+      slot.reset(new WebGLExtensionTextureFloatLinear(this));
+      break;
+    case WebGLExtensionID::OES_texture_half_float:
+      slot.reset(new WebGLExtensionTextureHalfFloat(this));
+      break;
+    case WebGLExtensionID::OES_texture_half_float_linear:
+      slot.reset(new WebGLExtensionTextureHalfFloatLinear(this));
+      break;
+    case WebGLExtensionID::OES_vertex_array_object:
+      slot.reset(new WebGLExtensionVertexArray(this));
+      break;
+
+    // WEBGL_
+    case WebGLExtensionID::OVR_multiview2:
+      slot.reset(new WebGLExtensionMultiview(this));
+      break;
+
+    // WEBGL_
+    case WebGLExtensionID::WEBGL_color_buffer_float:
+      slot.reset(new WebGLExtensionColorBufferFloat(this));
+      break;
+    case WebGLExtensionID::WEBGL_compressed_texture_astc:
+      slot.reset(new WebGLExtensionCompressedTextureASTC(this));
+      break;
+    case WebGLExtensionID::WEBGL_compressed_texture_etc:
+      slot.reset(new WebGLExtensionCompressedTextureES3(this));
+      break;
+    case WebGLExtensionID::WEBGL_compressed_texture_etc1:
+      slot.reset(new WebGLExtensionCompressedTextureETC1(this));
+      break;
+    case WebGLExtensionID::WEBGL_compressed_texture_pvrtc:
+      slot.reset(new WebGLExtensionCompressedTexturePVRTC(this));
+      break;
+    case WebGLExtensionID::WEBGL_compressed_texture_s3tc:
+      slot.reset(new WebGLExtensionCompressedTextureS3TC(this));
+      break;
+    case WebGLExtensionID::WEBGL_compressed_texture_s3tc_srgb:
+      slot.reset(new WebGLExtensionCompressedTextureS3TC_SRGB(this));
+      break;
+    case WebGLExtensionID::WEBGL_debug_renderer_info:
+      slot.reset(new WebGLExtensionDebugRendererInfo(this));
+      break;
+    case WebGLExtensionID::WEBGL_debug_shaders:
+      slot.reset(new WebGLExtensionDebugShaders(this));
+      break;
+    case WebGLExtensionID::WEBGL_depth_texture:
+      slot.reset(new WebGLExtensionDepthTexture(this));
+      break;
+    case WebGLExtensionID::WEBGL_draw_buffers:
+      slot.reset(new WebGLExtensionDrawBuffers(this));
+      break;
+    case WebGLExtensionID::WEBGL_explicit_present:
+      slot.reset(new WebGLExtensionExplicitPresent(this));
+      break;
+    case WebGLExtensionID::WEBGL_lose_context:
+      slot.reset(new WebGLExtensionLoseContext(this));
+      break;
+    case WebGLExtensionID::WEBGL_provoking_vertex:
+      slot.reset(new WebGLExtensionProvokingVertex(this));
+      break;
+
+    case WebGLExtensionID::Max:
+      MOZ_CRASH();
+  }
+  MOZ_ASSERT(slot);
+  const auto& obj = slot;
+
+  if (explicitly && !obj->IsExplicit()) {
+    obj->SetExplicit();
+  }
+
+  // Also enable implied extensions.
+  switch (ext) {
+    case WebGLExtensionID::EXT_color_buffer_float:
+      RequestExtension(WebGLExtensionID::EXT_float_blend, false);
+      break;
+
+    case WebGLExtensionID::OES_texture_float:
+      RequestExtension(WebGLExtensionID::EXT_float_blend, false);
+      RequestExtension(WebGLExtensionID::WEBGL_color_buffer_float, false);
+      break;
+
+    case WebGLExtensionID::OES_texture_half_float:
+      RequestExtension(WebGLExtensionID::EXT_color_buffer_half_float, false);
+      break;
+
+    case WebGLExtensionID::WEBGL_color_buffer_float:
+      RequestExtension(WebGLExtensionID::EXT_float_blend, false);
+      break;
+
+    default:
+      break;
+  }
+}
+
+}  // namespace mozilla