Add m-esr52 at 52.6.0

1 files changed, 1952 insertions, 0 deletions

diff --git a/dom/canvas/WebGLFramebuffer.cpp b/dom/canvas/WebGLFramebuffer.cpp
new file mode 100644
index 000000000..35efa4f16
--- /dev/null
+++ b/dom/canvas/WebGLFramebuffer.cpp
@@ -0,0 +1,1952 @@
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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 "WebGLFramebuffer.h"
+
+// You know it's going to be fun when these two show up:
+#include <algorithm>
+#include <iterator>
+
+#include "GLContext.h"
+#include "GLScreenBuffer.h"
+#include "mozilla/dom/WebGLRenderingContextBinding.h"
+#include "nsPrintfCString.h"
+#include "WebGLContext.h"
+#include "WebGLContextUtils.h"
+#include "WebGLExtensions.h"
+#include "WebGLRenderbuffer.h"
+#include "WebGLTexture.h"
+
+namespace mozilla {
+
+WebGLFBAttachPoint::WebGLFBAttachPoint()
+    : mFB(nullptr)
+    , mAttachmentPoint(0)
+    , mTexImageTarget(LOCAL_GL_NONE)
+    , mTexImageLayer(0)
+    , mTexImageLevel(0)
+{ }
+
+WebGLFBAttachPoint::WebGLFBAttachPoint(WebGLFramebuffer* fb, GLenum attachmentPoint)
+    : mFB(fb)
+    , mAttachmentPoint(attachmentPoint)
+    , mTexImageTarget(LOCAL_GL_NONE)
+    , mTexImageLayer(0)
+    , mTexImageLevel(0)
+{ }
+
+WebGLFBAttachPoint::~WebGLFBAttachPoint()
+{
+    MOZ_ASSERT(mFB, "Should have been Init'd.");
+    MOZ_ASSERT(!mRenderbufferPtr);
+    MOZ_ASSERT(!mTexturePtr);
+}
+
+void
+WebGLFBAttachPoint::Unlink()
+{
+    Clear();
+}
+
+bool
+WebGLFBAttachPoint::IsDeleteRequested() const
+{
+    return Texture() ? Texture()->IsDeleteRequested()
+         : Renderbuffer() ? Renderbuffer()->IsDeleteRequested()
+         : false;
+}
+
+bool
+WebGLFBAttachPoint::IsDefined() const
+{
+    /*
+    return (Renderbuffer() && Renderbuffer()->IsDefined()) ||
+           (Texture() && Texture()->ImageInfoAt(mTexImageTarget,
+                                                mTexImageLevel).IsDefined());
+    */
+    return (Renderbuffer() || Texture());
+}
+
+const webgl::FormatUsageInfo*
+WebGLFBAttachPoint::Format() const
+{
+    MOZ_ASSERT(IsDefined());
+
+    if (Texture())
+        return Texture()->ImageInfoAt(mTexImageTarget, mTexImageLevel).mFormat;
+
+    if (Renderbuffer())
+        return Renderbuffer()->Format();
+
+    return nullptr;
+}
+
+uint32_t
+WebGLFBAttachPoint::Samples() const
+{
+    MOZ_ASSERT(IsDefined());
+
+    if (mRenderbufferPtr)
+        return mRenderbufferPtr->Samples();
+
+    return 0;
+}
+
+bool
+WebGLFBAttachPoint::HasAlpha() const
+{
+    return Format()->format->a;
+}
+
+bool
+WebGLFBAttachPoint::IsReadableFloat() const
+{
+    auto formatUsage = Format();
+    MOZ_ASSERT(formatUsage);
+
+    auto format = formatUsage->format;
+    if (!format->IsColorFormat())
+        return false;
+
+    return format->componentType == webgl::ComponentType::Float;
+}
+
+void
+WebGLFBAttachPoint::Clear()
+{
+    if (mRenderbufferPtr) {
+        MOZ_ASSERT(!mTexturePtr);
+        mRenderbufferPtr->UnmarkAttachment(*this);
+    } else if (mTexturePtr) {
+        mTexturePtr->ImageInfoAt(mTexImageTarget, mTexImageLevel).RemoveAttachPoint(this);
+    }
+
+    mTexturePtr = nullptr;
+    mRenderbufferPtr = nullptr;
+
+    OnBackingStoreRespecified();
+}
+
+void
+WebGLFBAttachPoint::SetTexImage(WebGLTexture* tex, TexImageTarget target, GLint level,
+                                GLint layer)
+{
+    Clear();
+
+    mTexturePtr = tex;
+    mTexImageTarget = target;
+    mTexImageLevel = level;
+    mTexImageLayer = layer;
+
+    if (mTexturePtr) {
+        mTexturePtr->ImageInfoAt(mTexImageTarget, mTexImageLevel).AddAttachPoint(this);
+    }
+}
+
+void
+WebGLFBAttachPoint::SetRenderbuffer(WebGLRenderbuffer* rb)
+{
+    Clear();
+
+    mRenderbufferPtr = rb;
+
+    if (mRenderbufferPtr) {
+        mRenderbufferPtr->MarkAttachment(*this);
+    }
+}
+
+bool
+WebGLFBAttachPoint::HasUninitializedImageData() const
+{
+    if (!HasImage())
+        return false;
+
+    if (mRenderbufferPtr)
+        return mRenderbufferPtr->HasUninitializedImageData();
+
+    MOZ_ASSERT(mTexturePtr);
+
+    auto& imageInfo = mTexturePtr->ImageInfoAt(mTexImageTarget, mTexImageLevel);
+    MOZ_ASSERT(imageInfo.IsDefined());
+
+    return !imageInfo.IsDataInitialized();
+}
+
+void
+WebGLFBAttachPoint::SetImageDataStatus(WebGLImageDataStatus newStatus) const
+{
+    if (!HasImage())
+        return;
+
+    if (mRenderbufferPtr) {
+        mRenderbufferPtr->mImageDataStatus = newStatus;
+        return;
+    }
+
+    MOZ_ASSERT(mTexturePtr);
+
+    auto& imageInfo = mTexturePtr->ImageInfoAt(mTexImageTarget, mTexImageLevel);
+    MOZ_ASSERT(imageInfo.IsDefined());
+
+    const bool isDataInitialized = (newStatus == WebGLImageDataStatus::InitializedImageData);
+    imageInfo.SetIsDataInitialized(isDataInitialized, mTexturePtr);
+}
+
+bool
+WebGLFBAttachPoint::HasImage() const
+{
+    if (Texture() && Texture()->ImageInfoAt(mTexImageTarget, mTexImageLevel).IsDefined())
+        return true;
+
+    if (Renderbuffer() && Renderbuffer()->IsDefined())
+        return true;
+
+    return false;
+}
+
+void
+WebGLFBAttachPoint::Size(uint32_t* const out_width, uint32_t* const out_height) const
+{
+    MOZ_ASSERT(HasImage());
+
+    if (Renderbuffer()) {
+        *out_width = Renderbuffer()->Width();
+        *out_height = Renderbuffer()->Height();
+        return;
+    }
+
+    MOZ_ASSERT(Texture());
+    MOZ_ASSERT(Texture()->ImageInfoAt(mTexImageTarget, mTexImageLevel).IsDefined());
+    const auto& imageInfo = Texture()->ImageInfoAt(mTexImageTarget, mTexImageLevel);
+
+    *out_width = imageInfo.mWidth;
+    *out_height = imageInfo.mHeight;
+}
+
+void
+WebGLFBAttachPoint::OnBackingStoreRespecified() const
+{
+    mFB->InvalidateFramebufferStatus();
+}
+
+void
+WebGLFBAttachPoint::AttachmentName(nsCString* out) const
+{
+    switch (mAttachmentPoint) {
+    case LOCAL_GL_DEPTH_ATTACHMENT:
+        out->AssignLiteral("DEPTH_ATTACHMENT");
+        return;
+
+    case LOCAL_GL_STENCIL_ATTACHMENT:
+        out->AssignLiteral("STENCIL_ATTACHMENT");
+        return;
+
+    case LOCAL_GL_DEPTH_STENCIL_ATTACHMENT:
+        out->AssignLiteral("DEPTH_STENCIL_ATTACHMENT");
+        return;
+
+    default:
+        MOZ_ASSERT(mAttachmentPoint >= LOCAL_GL_COLOR_ATTACHMENT0);
+        out->AssignLiteral("COLOR_ATTACHMENT");
+        const uint32_t n = mAttachmentPoint - LOCAL_GL_COLOR_ATTACHMENT0;
+        out->AppendInt(n);
+        return;
+    }
+}
+
+bool
+WebGLFBAttachPoint::IsComplete(WebGLContext* webgl, nsCString* const out_info) const
+{
+    MOZ_ASSERT(IsDefined());
+
+    if (!HasImage()) {
+        AttachmentName(out_info);
+        out_info->AppendLiteral("'s image is not defined");
+        return false;
+    }
+
+    uint32_t width;
+    uint32_t height;
+    Size(&width, &height);
+    if (!width || !height) {
+        AttachmentName(out_info);
+        out_info->AppendLiteral(" has no width or height");
+        return false;
+    }
+
+    const auto formatUsage = Format();
+    if (!formatUsage->IsRenderable()) {
+        nsAutoCString attachName;
+        AttachmentName(&attachName);
+
+        *out_info = nsPrintfCString("%s has an effective format of %s, which is not"
+                                    " renderable",
+                                    attachName.BeginReading(), formatUsage->format->name);
+        return false;
+    }
+
+    if (webgl->IsWebGL2() && Texture() &&
+        Texture()->IsCubeMap() && !Texture()->IsCubeComplete())
+    {
+        AttachmentName(out_info);
+        out_info->AppendLiteral(" is not cube complete");
+        return false;
+    }
+
+    const auto format = formatUsage->format;
+
+    bool hasRequiredBits;
+
+    switch (mAttachmentPoint) {
+    case LOCAL_GL_DEPTH_ATTACHMENT:
+        hasRequiredBits = format->d;
+        break;
+
+    case LOCAL_GL_STENCIL_ATTACHMENT:
+        hasRequiredBits = format->s;
+        break;
+
+    case LOCAL_GL_DEPTH_STENCIL_ATTACHMENT:
+        MOZ_ASSERT(!webgl->IsWebGL2());
+        hasRequiredBits = (format->d && format->s);
+        break;
+
+    default:
+        MOZ_ASSERT(mAttachmentPoint >= LOCAL_GL_COLOR_ATTACHMENT0);
+        hasRequiredBits = format->IsColorFormat();
+        break;
+    }
+
+    if (!hasRequiredBits) {
+        AttachmentName(out_info);
+        out_info->AppendLiteral("'s format is missing required color/depth/stencil bits");
+        return false;
+    }
+
+    if (!webgl->IsWebGL2()) {
+        bool hasSurplusPlanes = false;
+
+        switch (mAttachmentPoint) {
+        case LOCAL_GL_DEPTH_ATTACHMENT:
+            hasSurplusPlanes = format->s;
+            break;
+
+        case LOCAL_GL_STENCIL_ATTACHMENT:
+            hasSurplusPlanes = format->d;
+            break;
+        }
+
+        if (hasSurplusPlanes) {
+            AttachmentName(out_info);
+            out_info->AppendLiteral("'s format has depth or stencil bits when it"
+                                    " shouldn't");
+            return false;
+        }
+    }
+
+    return true;
+}
+
+void
+WebGLFBAttachPoint::Resolve(gl::GLContext* gl) const
+{
+    if (!HasImage())
+        return;
+
+    if (Renderbuffer()) {
+        Renderbuffer()->DoFramebufferRenderbuffer(LOCAL_GL_FRAMEBUFFER, mAttachmentPoint);
+        return;
+    }
+    MOZ_ASSERT(Texture());
+
+    MOZ_ASSERT(gl == Texture()->mContext->GL());
+
+    const auto& texName = Texture()->mGLName;
+
+    ////
+
+    const auto fnAttach2D = [&](GLenum attachmentPoint) {
+        gl->fFramebufferTexture2D(LOCAL_GL_FRAMEBUFFER, attachmentPoint,
+                                  mTexImageTarget.get(), texName, mTexImageLevel);
+    };
+
+    ////
+
+    switch (mTexImageTarget.get()) {
+    case LOCAL_GL_TEXTURE_2D:
+    case LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_X:
+    case LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_X:
+    case LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_Y:
+    case LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_Y:
+    case LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_Z:
+    case LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_Z:
+        if (mAttachmentPoint == LOCAL_GL_DEPTH_STENCIL_ATTACHMENT) {
+            fnAttach2D(LOCAL_GL_DEPTH_ATTACHMENT);
+            fnAttach2D(LOCAL_GL_STENCIL_ATTACHMENT);
+        } else {
+            fnAttach2D(mAttachmentPoint);
+        }
+        break;
+
+    case LOCAL_GL_TEXTURE_2D_ARRAY:
+    case LOCAL_GL_TEXTURE_3D:
+        // If we have fFramebufferTextureLayer, we can rely on having
+        // DEPTH_STENCIL_ATTACHMENT.
+        gl->fFramebufferTextureLayer(LOCAL_GL_FRAMEBUFFER, mAttachmentPoint, texName,
+                                     mTexImageLevel, mTexImageLayer);
+        break;
+    }
+}
+
+JS::Value
+WebGLFBAttachPoint::GetParameter(const char* funcName, WebGLContext* webgl, JSContext* cx,
+                                 GLenum target, GLenum attachment, GLenum pname,
+                                 ErrorResult* const out_error) const
+{
+    const bool hasAttachment = (mTexturePtr || mRenderbufferPtr);
+    if (!hasAttachment) {
+        // Divergent between GLES 3 and 2.
+
+        // GLES 2.0.25 p127:
+        // "If the value of FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is NONE, then querying any
+        //  other pname will generate INVALID_ENUM."
+
+        // GLES 3.0.4 p240:
+        // "If the value of FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE is NONE, no framebuffer is
+        //  bound to target. In this case querying pname
+        //  FRAMEBUFFER_ATTACHMENT_OBJECT_NAME will return zero, and all other queries
+        //  will generate an INVALID_OPERATION error."
+        switch (pname) {
+        case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE:
+            return JS::Int32Value(LOCAL_GL_NONE);
+
+        case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME:
+            if (webgl->IsWebGL2())
+                return JS::NullValue();
+
+            break;
+
+        default:
+            break;
+        }
+        nsCString attachmentName;
+        WebGLContext::EnumName(attachment, &attachmentName);
+        if (webgl->IsWebGL2()) {
+            webgl->ErrorInvalidOperation("%s: No attachment at %s.", funcName,
+                                         attachmentName.BeginReading());
+        } else {
+            webgl->ErrorInvalidEnum("%s: No attachment at %s.", funcName,
+                                    attachmentName.BeginReading());
+        }
+        return JS::NullValue();
+    }
+
+    bool isPNameValid = false;
+    switch (pname) {
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE:
+        return JS::Int32Value(mTexturePtr ? LOCAL_GL_TEXTURE
+                                          : LOCAL_GL_RENDERBUFFER);
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME:
+        return (mTexturePtr ? webgl->WebGLObjectAsJSValue(cx, mTexturePtr.get(),
+                                                          *out_error)
+                            : webgl->WebGLObjectAsJSValue(cx, mRenderbufferPtr.get(),
+                                                          *out_error));
+
+        //////
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL:
+        if (mTexturePtr)
+            return JS::Int32Value(MipLevel());
+        break;
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE:
+        if (mTexturePtr) {
+            GLenum face = 0;
+            if (mTexturePtr->Target() == LOCAL_GL_TEXTURE_CUBE_MAP) {
+                face = ImageTarget().get();
+            }
+            return JS::Int32Value(face);
+        }
+        break;
+
+        //////
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER:
+        if (webgl->IsWebGL2() && mTexturePtr) {
+            int32_t layer = 0;
+            if (ImageTarget() == LOCAL_GL_TEXTURE_2D_ARRAY ||
+                ImageTarget() == LOCAL_GL_TEXTURE_3D)
+            {
+                layer = Layer();
+            }
+            return JS::Int32Value(layer);
+        }
+        break;
+
+        //////
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE:
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE:
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE:
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE:
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE:
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE:
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE:
+        isPNameValid = webgl->IsWebGL2();
+        break;
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING:
+        isPNameValid = (webgl->IsWebGL2() ||
+                        webgl->IsExtensionEnabled(WebGLExtensionID::EXT_sRGB));
+        break;
+    }
+
+    if (!isPNameValid) {
+        webgl->ErrorInvalidEnum("%s: Invalid pname: 0x%04x", funcName, pname);
+        return JS::NullValue();
+    }
+
+    const auto usage = Format();
+    if (!usage) {
+        if (pname == LOCAL_GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING)
+            return JS::NumberValue(LOCAL_GL_LINEAR);
+
+        return JS::NullValue();
+    }
+
+    auto format = usage->format;
+
+    GLint ret = 0;
+    switch (pname) {
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE:
+        ret = format->r;
+        break;
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE:
+        ret = format->g;
+        break;
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE:
+        ret = format->b;
+        break;
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE:
+        ret = format->a;
+        break;
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE:
+        ret = format->d;
+        break;
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE:
+        ret = format->s;
+        break;
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING:
+        ret = (format->isSRGB ? LOCAL_GL_SRGB
+                              : LOCAL_GL_LINEAR);
+        break;
+
+    case LOCAL_GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE:
+        MOZ_ASSERT(attachment != LOCAL_GL_DEPTH_STENCIL_ATTACHMENT);
+
+        if (format->componentType == webgl::ComponentType::Special) {
+            // Special format is used for DS mixed format(e.g. D24S8 and D32FS8).
+            MOZ_ASSERT(format->unsizedFormat == webgl::UnsizedFormat::DEPTH_STENCIL);
+            MOZ_ASSERT(attachment == LOCAL_GL_DEPTH_ATTACHMENT ||
+                       attachment == LOCAL_GL_STENCIL_ATTACHMENT);
+
+            if (attachment == LOCAL_GL_DEPTH_ATTACHMENT) {
+                switch (format->effectiveFormat) {
+                case webgl::EffectiveFormat::DEPTH24_STENCIL8:
+                    format = webgl::GetFormat(webgl::EffectiveFormat::DEPTH_COMPONENT24);
+                    break;
+                case webgl::EffectiveFormat::DEPTH32F_STENCIL8:
+                    format = webgl::GetFormat(webgl::EffectiveFormat::DEPTH_COMPONENT32F);
+                    break;
+                default:
+                    MOZ_ASSERT(false, "no matched DS format");
+                    break;
+                }
+            } else if (attachment == LOCAL_GL_STENCIL_ATTACHMENT) {
+                switch (format->effectiveFormat) {
+                case webgl::EffectiveFormat::DEPTH24_STENCIL8:
+                case webgl::EffectiveFormat::DEPTH32F_STENCIL8:
+                    format = webgl::GetFormat(webgl::EffectiveFormat::STENCIL_INDEX8);
+                    break;
+                default:
+                    MOZ_ASSERT(false, "no matched DS format");
+                    break;
+                }
+            }
+        }
+
+        switch (format->componentType) {
+        case webgl::ComponentType::None:
+            ret = LOCAL_GL_NONE;
+            break;
+        case webgl::ComponentType::Int:
+            ret = LOCAL_GL_INT;
+            break;
+        case webgl::ComponentType::UInt:
+            ret = LOCAL_GL_UNSIGNED_INT;
+            break;
+        case webgl::ComponentType::NormInt:
+            ret = LOCAL_GL_SIGNED_NORMALIZED;
+            break;
+        case webgl::ComponentType::NormUInt:
+            ret = LOCAL_GL_UNSIGNED_NORMALIZED;
+            break;
+        case webgl::ComponentType::Float:
+            ret = LOCAL_GL_FLOAT;
+            break;
+        default:
+            MOZ_ASSERT(false, "No matched component type");
+            break;
+        }
+        break;
+
+    default:
+        MOZ_ASSERT(false, "Missing case.");
+        break;
+    }
+
+    return JS::Int32Value(ret);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////////
+// WebGLFramebuffer
+
+WebGLFramebuffer::WebGLFramebuffer(WebGLContext* webgl, GLuint fbo)
+    : WebGLRefCountedObject(webgl)
+    , mGLName(fbo)
+#ifdef ANDROID
+    , mIsFB(false)
+#endif
+    , mDepthAttachment(this, LOCAL_GL_DEPTH_ATTACHMENT)
+    , mStencilAttachment(this, LOCAL_GL_STENCIL_ATTACHMENT)
+    , mDepthStencilAttachment(this, LOCAL_GL_DEPTH_STENCIL_ATTACHMENT)
+{
+    mContext->mFramebuffers.insertBack(this);
+
+    size_t i = 0;
+    for (auto& cur : mColorAttachments) {
+        new (&cur) WebGLFBAttachPoint(this, LOCAL_GL_COLOR_ATTACHMENT0 + i);
+        i++;
+    }
+
+    mColorDrawBuffers.push_back(&mColorAttachments[0]);
+    mColorReadBuffer = &mColorAttachments[0];
+}
+
+void
+WebGLFramebuffer::Delete()
+{
+    InvalidateFramebufferStatus();
+
+    mDepthAttachment.Clear();
+    mStencilAttachment.Clear();
+    mDepthStencilAttachment.Clear();
+
+    for (auto& cur : mColorAttachments) {
+        cur.Clear();
+    }
+
+    mContext->MakeContextCurrent();
+    mContext->gl->fDeleteFramebuffers(1, &mGLName);
+
+    LinkedListElement<WebGLFramebuffer>::removeFrom(mContext->mFramebuffers);
+
+#ifdef ANDROID
+    mIsFB = false;
+#endif
+}
+
+////
+
+Maybe<WebGLFBAttachPoint*>
+WebGLFramebuffer::GetColorAttachPoint(GLenum attachPoint)
+{
+    if (attachPoint == LOCAL_GL_NONE)
+        return Some<WebGLFBAttachPoint*>(nullptr);
+
+    if (attachPoint < LOCAL_GL_COLOR_ATTACHMENT0)
+        return Nothing();
+
+    const size_t colorId = attachPoint - LOCAL_GL_COLOR_ATTACHMENT0;
+
+    MOZ_ASSERT(mContext->mImplMaxColorAttachments <= kMaxColorAttachments);
+    if (colorId >= mContext->mImplMaxColorAttachments)
+        return Nothing();
+
+    return Some(&mColorAttachments[colorId]);
+}
+
+Maybe<WebGLFBAttachPoint*>
+WebGLFramebuffer::GetAttachPoint(GLenum attachPoint)
+{
+    switch (attachPoint) {
+    case LOCAL_GL_DEPTH_STENCIL_ATTACHMENT:
+        return Some(&mDepthStencilAttachment);
+
+    case LOCAL_GL_DEPTH_ATTACHMENT:
+        return Some(&mDepthAttachment);
+
+    case LOCAL_GL_STENCIL_ATTACHMENT:
+        return Some(&mStencilAttachment);
+
+    default:
+        return GetColorAttachPoint(attachPoint);
+    }
+}
+
+#define FOR_EACH_ATTACHMENT(X)            \
+    X(mDepthAttachment);                  \
+    X(mStencilAttachment);                \
+    X(mDepthStencilAttachment);           \
+                                          \
+    for (auto& cur : mColorAttachments) { \
+        X(cur);                           \
+    }
+
+void
+WebGLFramebuffer::DetachTexture(const WebGLTexture* tex)
+{
+    const auto fnDetach = [&](WebGLFBAttachPoint& attach) {
+        if (attach.Texture() == tex) {
+            attach.Clear();
+        }
+    };
+
+    FOR_EACH_ATTACHMENT(fnDetach)
+}
+
+void
+WebGLFramebuffer::DetachRenderbuffer(const WebGLRenderbuffer* rb)
+{
+    const auto fnDetach = [&](WebGLFBAttachPoint& attach) {
+        if (attach.Renderbuffer() == rb) {
+            attach.Clear();
+        }
+    };
+
+    FOR_EACH_ATTACHMENT(fnDetach)
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Completeness
+
+bool
+WebGLFramebuffer::HasDefinedAttachments() const
+{
+    bool hasAttachments = false;
+    const auto func = [&](const WebGLFBAttachPoint& attach) {
+        hasAttachments |= attach.IsDefined();
+    };
+
+    FOR_EACH_ATTACHMENT(func)
+    return hasAttachments;
+}
+
+bool
+WebGLFramebuffer::HasIncompleteAttachments(nsCString* const out_info) const
+{
+    bool hasIncomplete = false;
+    const auto func = [&](const WebGLFBAttachPoint& cur) {
+        if (!cur.IsDefined())
+            return; // Not defined, so can't count as incomplete.
+
+        hasIncomplete |= !cur.IsComplete(mContext, out_info);
+    };
+
+    FOR_EACH_ATTACHMENT(func)
+    return hasIncomplete;
+}
+
+bool
+WebGLFramebuffer::AllImageRectsMatch() const
+{
+    MOZ_ASSERT(HasDefinedAttachments());
+    DebugOnly<nsCString> fbStatusInfo;
+    MOZ_ASSERT(!HasIncompleteAttachments(&fbStatusInfo));
+
+    bool needsInit = true;
+    uint32_t width = 0;
+    uint32_t height = 0;
+
+    bool hasMismatch = false;
+    const auto func = [&](const WebGLFBAttachPoint& attach) {
+        if (!attach.HasImage())
+            return;
+
+        uint32_t curWidth;
+        uint32_t curHeight;
+        attach.Size(&curWidth, &curHeight);
+
+        if (needsInit) {
+            needsInit = false;
+            width = curWidth;
+            height = curHeight;
+            return;
+        }
+
+        hasMismatch |= (curWidth != width ||
+                        curHeight != height);
+    };
+
+    FOR_EACH_ATTACHMENT(func)
+    return !hasMismatch;
+}
+
+bool
+WebGLFramebuffer::AllImageSamplesMatch() const
+{
+    MOZ_ASSERT(HasDefinedAttachments());
+    DebugOnly<nsCString> fbStatusInfo;
+    MOZ_ASSERT(!HasIncompleteAttachments(&fbStatusInfo));
+
+    bool needsInit = true;
+    uint32_t samples = 0;
+
+    bool hasMismatch = false;
+    const auto func = [&](const WebGLFBAttachPoint& attach) {
+        if (!attach.HasImage())
+          return;
+
+        const uint32_t curSamples = attach.Samples();
+
+        if (needsInit) {
+            needsInit = false;
+            samples = curSamples;
+            return;
+        }
+
+        hasMismatch |= (curSamples != samples);
+    };
+
+    FOR_EACH_ATTACHMENT(func)
+    return !hasMismatch;
+}
+
+#undef FOR_EACH_ATTACHMENT
+
+FBStatus
+WebGLFramebuffer::PrecheckFramebufferStatus(nsCString* const out_info) const
+{
+    MOZ_ASSERT(mContext->mBoundDrawFramebuffer == this ||
+               mContext->mBoundReadFramebuffer == this);
+
+    if (!HasDefinedAttachments())
+        return LOCAL_GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT; // No attachments
+
+    if (HasIncompleteAttachments(out_info))
+        return LOCAL_GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT;
+
+    if (!AllImageRectsMatch())
+        return LOCAL_GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS; // Inconsistent sizes
+
+    if (!AllImageSamplesMatch())
+        return LOCAL_GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE; // Inconsistent samples
+
+    if (mContext->IsWebGL2()) {
+        MOZ_ASSERT(!mDepthStencilAttachment.IsDefined());
+    } else {
+        const auto depthOrStencilCount = int(mDepthAttachment.IsDefined()) +
+                                         int(mStencilAttachment.IsDefined()) +
+                                         int(mDepthStencilAttachment.IsDefined());
+        if (depthOrStencilCount > 1)
+            return LOCAL_GL_FRAMEBUFFER_UNSUPPORTED;
+    }
+
+    return LOCAL_GL_FRAMEBUFFER_COMPLETE;
+}
+
+////////////////////////////////////////
+// Validation
+
+bool
+WebGLFramebuffer::ValidateAndInitAttachments(const char* funcName)
+{
+    MOZ_ASSERT(mContext->mBoundDrawFramebuffer == this ||
+               mContext->mBoundReadFramebuffer == this);
+
+    const auto fbStatus = CheckFramebufferStatus(funcName);
+    if (fbStatus == LOCAL_GL_FRAMEBUFFER_COMPLETE)
+        return true;
+
+    mContext->ErrorInvalidFramebufferOperation("%s: Framebuffer must be"
+                                               " complete.",
+                                               funcName);
+    return false;
+}
+
+bool
+WebGLFramebuffer::ValidateClearBufferType(const char* funcName, GLenum buffer,
+                                          uint32_t drawBuffer, GLenum funcType) const
+{
+    if (buffer != LOCAL_GL_COLOR)
+        return true;
+
+    const auto& attach = mColorAttachments[drawBuffer];
+    if (!attach.IsDefined())
+        return true;
+
+    if (!count(mColorDrawBuffers.begin(), mColorDrawBuffers.end(), &attach))
+        return true; // DRAW_BUFFERi set to NONE.
+
+    GLenum attachType;
+    switch (attach.Format()->format->componentType) {
+    case webgl::ComponentType::Int:
+        attachType = LOCAL_GL_INT;
+        break;
+    case webgl::ComponentType::UInt:
+        attachType = LOCAL_GL_UNSIGNED_INT;
+        break;
+    default:
+        attachType = LOCAL_GL_FLOAT;
+        break;
+    }
+
+    if (attachType != funcType) {
+        mContext->ErrorInvalidOperation("%s: This attachment is of type 0x%04x, but"
+                                        " this function is of type 0x%04x.",
+                                        funcName, attachType, funcType);
+        return false;
+    }
+
+    return true;
+}
+
+bool
+WebGLFramebuffer::ValidateForRead(const char* funcName,
+                                  const webgl::FormatUsageInfo** const out_format,
+                                  uint32_t* const out_width, uint32_t* const out_height)
+{
+    if (!ValidateAndInitAttachments(funcName))
+        return false;
+
+    if (!mColorReadBuffer) {
+        mContext->ErrorInvalidOperation("%s: READ_BUFFER must not be NONE.", funcName);
+        return false;
+    }
+
+    if (!mColorReadBuffer->IsDefined()) {
+        mContext->ErrorInvalidOperation("%s: The READ_BUFFER attachment is not defined.",
+                                        funcName);
+        return false;
+    }
+
+    if (mColorReadBuffer->Samples()) {
+        mContext->ErrorInvalidOperation("%s: The READ_BUFFER attachment is multisampled.",
+                                        funcName);
+        return false;
+    }
+
+    *out_format = mColorReadBuffer->Format();
+    mColorReadBuffer->Size(out_width, out_height);
+    return true;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Resolution and caching
+
+void
+WebGLFramebuffer::ResolveAttachments() const
+{
+    const auto& gl = mContext->gl;
+
+    ////
+    // Nuke attachment points.
+
+    for (uint32_t i = 0; i < mContext->mImplMaxColorAttachments; i++) {
+        const GLenum attachEnum = LOCAL_GL_COLOR_ATTACHMENT0 + i;
+        gl->fFramebufferRenderbuffer(LOCAL_GL_FRAMEBUFFER, attachEnum,
+                                     LOCAL_GL_RENDERBUFFER, 0);
+    }
+
+    gl->fFramebufferRenderbuffer(LOCAL_GL_FRAMEBUFFER, LOCAL_GL_DEPTH_ATTACHMENT,
+                                 LOCAL_GL_RENDERBUFFER, 0);
+    gl->fFramebufferRenderbuffer(LOCAL_GL_FRAMEBUFFER, LOCAL_GL_STENCIL_ATTACHMENT,
+                                 LOCAL_GL_RENDERBUFFER, 0);
+
+    ////
+
+    for (const auto& attach : mColorAttachments) {
+        attach.Resolve(gl);
+    }
+
+    mDepthAttachment.Resolve(gl);
+    mStencilAttachment.Resolve(gl);
+    mDepthStencilAttachment.Resolve(gl);
+}
+
+bool
+WebGLFramebuffer::ResolveAttachmentData(const char* funcName) const
+{
+    //////
+    // Check if we need to initialize anything
+
+    const auto fnIs3D = [&](const WebGLFBAttachPoint& attach) {
+        const auto& tex = attach.Texture();
+        if (!tex)
+            return false;
+
+        const auto& info = tex->ImageInfoAt(attach.ImageTarget(), attach.MipLevel());
+        if (info.mDepth == 1)
+            return false;
+
+        return true;
+    };
+
+    uint32_t clearBits = 0;
+    std::vector<const WebGLFBAttachPoint*> attachmentsToClear;
+    std::vector<const WebGLFBAttachPoint*> colorAttachmentsToClear;
+    std::vector<const WebGLFBAttachPoint*> tex3DAttachmentsToInit;
+
+    const auto fnGather = [&](const WebGLFBAttachPoint& attach, GLenum attachClearBits) {
+        if (!attach.HasUninitializedImageData())
+            return false;
+
+        if (fnIs3D(attach)) {
+            tex3DAttachmentsToInit.push_back(&attach);
+            return false;
+        }
+
+        clearBits |= attachClearBits;
+        attachmentsToClear.push_back(&attach);
+        return true;
+    };
+
+    //////
+
+    for (auto& cur : mColorDrawBuffers) {
+        if (fnGather(*cur, LOCAL_GL_COLOR_BUFFER_BIT)) {
+            colorAttachmentsToClear.push_back(cur);
+        }
+    }
+
+    fnGather(mDepthAttachment, LOCAL_GL_DEPTH_BUFFER_BIT);
+    fnGather(mStencilAttachment, LOCAL_GL_STENCIL_BUFFER_BIT);
+    fnGather(mDepthStencilAttachment, LOCAL_GL_DEPTH_BUFFER_BIT |
+                                      LOCAL_GL_STENCIL_BUFFER_BIT);
+
+    //////
+
+    for (const auto& attach : tex3DAttachmentsToInit) {
+        const auto& tex = attach->Texture();
+        if (!tex->InitializeImageData(funcName, attach->ImageTarget(),
+                                      attach->MipLevel()))
+        {
+            return false;
+        }
+    }
+
+    if (clearBits) {
+        const auto fnDrawBuffers = [&](const std::vector<const WebGLFBAttachPoint*>& src)
+        {
+            std::vector<GLenum> enumList;
+
+            for (const auto& cur : src) {
+                const auto& attachEnum = cur->mAttachmentPoint;
+                const GLenum attachId = attachEnum - LOCAL_GL_COLOR_ATTACHMENT0;
+
+                while (enumList.size() < attachId) {
+                    enumList.push_back(LOCAL_GL_NONE);
+                }
+                enumList.push_back(attachEnum);
+            }
+
+            mContext->gl->fDrawBuffers(enumList.size(), enumList.data());
+        };
+
+        ////
+        // Clear
+
+        mContext->MakeContextCurrent();
+
+        const bool hasDrawBuffers = mContext->HasDrawBuffers();
+        if (hasDrawBuffers) {
+            fnDrawBuffers(colorAttachmentsToClear);
+        }
+
+        {
+            gl::ScopedBindFramebuffer autoBind(mContext->gl, mGLName);
+
+            mContext->ForceClearFramebufferWithDefaultValues(clearBits, false);
+        }
+
+        if (hasDrawBuffers) {
+            RefreshDrawBuffers();
+        }
+
+        // Mark initialized.
+        for (const auto& cur : attachmentsToClear) {
+            cur->SetImageDataStatus(WebGLImageDataStatus::InitializedImageData);
+        }
+    }
+
+    return true;
+}
+
+WebGLFramebuffer::ResolvedData::ResolvedData(const WebGLFramebuffer& parent)
+{
+
+    texDrawBuffers.reserve(parent.mColorDrawBuffers.size() + 2); // +2 for depth+stencil.
+
+    const auto fnCommon = [&](const WebGLFBAttachPoint& attach) {
+        if (!attach.IsDefined())
+            return false;
+
+        if (attach.Texture()) {
+            texDrawBuffers.push_back(&attach);
+        }
+        return true;
+    };
+
+    ////
+
+    const auto fnDepthStencil = [&](const WebGLFBAttachPoint& attach) {
+        if (!fnCommon(attach))
+            return;
+
+        drawSet.insert(WebGLFBAttachPoint::Ordered(attach));
+        readSet.insert(WebGLFBAttachPoint::Ordered(attach));
+    };
+
+    fnDepthStencil(parent.mDepthAttachment);
+    fnDepthStencil(parent.mStencilAttachment);
+    fnDepthStencil(parent.mDepthStencilAttachment);
+
+    ////
+
+    for (const auto& pAttach : parent.mColorDrawBuffers) {
+        const auto& attach = *pAttach;
+        if (!fnCommon(attach))
+            return;
+
+        drawSet.insert(WebGLFBAttachPoint::Ordered(attach));
+    }
+
+    if (parent.mColorReadBuffer) {
+        const auto& attach = *parent.mColorReadBuffer;
+        if (!fnCommon(attach))
+            return;
+
+        readSet.insert(WebGLFBAttachPoint::Ordered(attach));
+    }
+}
+
+void
+WebGLFramebuffer::RefreshResolvedData()
+{
+    if (mResolvedCompleteData) {
+        mResolvedCompleteData.reset(new ResolvedData(*this));
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Entrypoints
+
+FBStatus
+WebGLFramebuffer::CheckFramebufferStatus(const char* funcName)
+{
+    if (IsResolvedComplete())
+        return LOCAL_GL_FRAMEBUFFER_COMPLETE;
+
+    // Ok, let's try to resolve it!
+
+    nsCString statusInfo;
+    FBStatus ret = PrecheckFramebufferStatus(&statusInfo);
+    do {
+        if (ret != LOCAL_GL_FRAMEBUFFER_COMPLETE)
+            break;
+
+        // Looks good on our end. Let's ask the driver.
+        gl::GLContext* const gl = mContext->gl;
+        gl->MakeCurrent();
+
+        const ScopedFBRebinder autoFB(mContext);
+        gl->fBindFramebuffer(LOCAL_GL_FRAMEBUFFER, mGLName);
+
+        ////
+
+        ResolveAttachments(); // OK, attach everything properly!
+        RefreshDrawBuffers();
+        RefreshReadBuffer();
+
+        ret = gl->fCheckFramebufferStatus(LOCAL_GL_FRAMEBUFFER);
+
+        ////
+
+        if (ret != LOCAL_GL_FRAMEBUFFER_COMPLETE) {
+            const nsPrintfCString text("Bad status according to the driver: 0x%04x",
+                                       ret.get());
+            statusInfo = text;
+            break;
+        }
+
+        if (!ResolveAttachmentData(funcName)) {
+            ret = LOCAL_GL_FRAMEBUFFER_UNSUPPORTED;
+            statusInfo.AssignLiteral("Failed to lazily-initialize attachment data.");
+            break;
+        }
+
+        mResolvedCompleteData.reset(new ResolvedData(*this));
+        return LOCAL_GL_FRAMEBUFFER_COMPLETE;
+    } while (false);
+
+    MOZ_ASSERT(ret != LOCAL_GL_FRAMEBUFFER_COMPLETE);
+    mContext->GenerateWarning("%s: Framebuffer not complete. (status: 0x%04x) %s",
+                              funcName, ret.get(), statusInfo.BeginReading());
+    return ret;
+}
+
+////
+
+void
+WebGLFramebuffer::RefreshDrawBuffers() const
+{
+    const auto& gl = mContext->gl;
+    if (!gl->IsSupported(gl::GLFeature::draw_buffers))
+        return;
+
+    // Prior to GL4.1, having a no-image FB attachment that's selected by DrawBuffers
+    // yields a framebuffer status of FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER.
+    // We could workaround this only on affected versions, but it's easier be
+    // unconditional.
+    std::vector<GLenum> driverBuffers(mContext->mImplMaxDrawBuffers, LOCAL_GL_NONE);
+    for (const auto& attach : mColorDrawBuffers) {
+        if (attach->HasImage()) {
+            const uint32_t index = attach->mAttachmentPoint - LOCAL_GL_COLOR_ATTACHMENT0;
+            driverBuffers[index] = attach->mAttachmentPoint;
+        }
+    }
+
+    gl->fDrawBuffers(driverBuffers.size(), driverBuffers.data());
+}
+
+void
+WebGLFramebuffer::RefreshReadBuffer() const
+{
+    const auto& gl = mContext->gl;
+    if (!gl->IsSupported(gl::GLFeature::read_buffer))
+        return;
+
+    // Prior to GL4.1, having a no-image FB attachment that's selected by ReadBuffer
+    // yields a framebuffer status of FRAMEBUFFER_INCOMPLETE_READ_BUFFER.
+    // We could workaround this only on affected versions, but it's easier be
+    // unconditional.
+    GLenum driverBuffer = LOCAL_GL_NONE;
+    if (mColorReadBuffer && mColorReadBuffer->HasImage()) {
+        driverBuffer = mColorReadBuffer->mAttachmentPoint;
+    }
+
+    gl->fReadBuffer(driverBuffer);
+}
+
+////
+
+void
+WebGLFramebuffer::DrawBuffers(const char* funcName, const dom::Sequence<GLenum>& buffers)
+{
+    if (buffers.Length() > mContext->mImplMaxDrawBuffers) {
+        // "An INVALID_VALUE error is generated if `n` is greater than MAX_DRAW_BUFFERS."
+        mContext->ErrorInvalidValue("%s: `buffers` must have a length <="
+                                    " MAX_DRAW_BUFFERS.", funcName);
+        return;
+    }
+
+    std::vector<const WebGLFBAttachPoint*> newColorDrawBuffers;
+    newColorDrawBuffers.reserve(buffers.Length());
+
+    for (size_t i = 0; i < buffers.Length(); i++) {
+        // "If the GL is bound to a draw framebuffer object, the `i`th buffer listed in
+        //  bufs must be COLOR_ATTACHMENTi or NONE. Specifying a buffer out of order,
+        //  BACK, or COLOR_ATTACHMENTm where `m` is greater than or equal to the value of
+        // MAX_COLOR_ATTACHMENTS, will generate the error INVALID_OPERATION.
+
+        // WEBGL_draw_buffers:
+        // "The value of the MAX_COLOR_ATTACHMENTS_WEBGL parameter must be greater than or
+        //  equal to that of the MAX_DRAW_BUFFERS_WEBGL parameter."
+        // This means that if buffers.Length() isn't larger than MaxDrawBuffers, it won't
+        // be larger than MaxColorAttachments.
+        const auto& cur = buffers[i];
+        if (cur == LOCAL_GL_COLOR_ATTACHMENT0 + i) {
+            const auto& attach = mColorAttachments[i];
+            newColorDrawBuffers.push_back(&attach);
+        } else if (cur != LOCAL_GL_NONE) {
+            const bool isColorEnum = (cur >= LOCAL_GL_COLOR_ATTACHMENT0 &&
+                                      cur < mContext->LastColorAttachmentEnum());
+            if (cur != LOCAL_GL_BACK &&
+                !isColorEnum)
+            {
+                mContext->ErrorInvalidEnum("%s: Unexpected enum in buffers.", funcName);
+                return;
+            }
+
+            mContext->ErrorInvalidOperation("%s: `buffers[i]` must be NONE or"
+                                            " COLOR_ATTACHMENTi.",
+                                            funcName);
+            return;
+        }
+    }
+
+    ////
+
+    mContext->MakeContextCurrent();
+
+    mColorDrawBuffers.swap(newColorDrawBuffers);
+    RefreshDrawBuffers(); // Calls glDrawBuffers.
+    RefreshResolvedData();
+}
+
+void
+WebGLFramebuffer::ReadBuffer(const char* funcName, GLenum attachPoint)
+{
+    const auto& maybeAttach = GetColorAttachPoint(attachPoint);
+    if (!maybeAttach) {
+        const char text[] = "%s: `mode` must be a COLOR_ATTACHMENTi, for 0 <= i <"
+                            " MAX_DRAW_BUFFERS.";
+        if (attachPoint == LOCAL_GL_BACK) {
+            mContext->ErrorInvalidOperation(text, funcName);
+        } else {
+            mContext->ErrorInvalidEnum(text, funcName);
+        }
+        return;
+    }
+    const auto& attach = maybeAttach.value(); // Might be nullptr.
+
+    ////
+
+    mContext->MakeContextCurrent();
+
+    mColorReadBuffer = attach;
+    RefreshReadBuffer(); // Calls glReadBuffer.
+    RefreshResolvedData();
+}
+
+////
+
+void
+WebGLFramebuffer::FramebufferRenderbuffer(const char* funcName, GLenum attachEnum,
+                                          GLenum rbtarget, WebGLRenderbuffer* rb)
+{
+    MOZ_ASSERT(mContext->mBoundDrawFramebuffer == this ||
+               mContext->mBoundReadFramebuffer == this);
+
+    // `attachment`
+    const auto maybeAttach = GetAttachPoint(attachEnum);
+    if (!maybeAttach || !maybeAttach.value()) {
+        mContext->ErrorInvalidEnum("%s: Bad `attachment`: 0x%x.", funcName, attachEnum);
+        return;
+    }
+    const auto& attach = maybeAttach.value();
+
+    // `rbTarget`
+    if (rbtarget != LOCAL_GL_RENDERBUFFER) {
+        mContext->ErrorInvalidEnumInfo("framebufferRenderbuffer: rbtarget:", rbtarget);
+        return;
+    }
+
+    // `rb`
+    if (rb && !mContext->ValidateObject("framebufferRenderbuffer: rb", *rb))
+        return;
+
+    // End of validation.
+
+    if (mContext->IsWebGL2() && attachEnum == LOCAL_GL_DEPTH_STENCIL_ATTACHMENT) {
+        mDepthAttachment.SetRenderbuffer(rb);
+        mStencilAttachment.SetRenderbuffer(rb);
+    } else {
+        attach->SetRenderbuffer(rb);
+    }
+
+    InvalidateFramebufferStatus();
+}
+
+void
+WebGLFramebuffer::FramebufferTexture2D(const char* funcName, GLenum attachEnum,
+                                       GLenum texImageTarget, WebGLTexture* tex,
+                                       GLint level)
+{
+    MOZ_ASSERT(mContext->mBoundDrawFramebuffer == this ||
+               mContext->mBoundReadFramebuffer == this);
+
+    // `attachment`
+    const auto maybeAttach = GetAttachPoint(attachEnum);
+    if (!maybeAttach || !maybeAttach.value()) {
+        mContext->ErrorInvalidEnum("%s: Bad `attachment`: 0x%x.", funcName, attachEnum);
+        return;
+    }
+    const auto& attach = maybeAttach.value();
+
+    // `texImageTarget`
+    if (texImageTarget != LOCAL_GL_TEXTURE_2D &&
+        (texImageTarget < LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_X ||
+         texImageTarget > LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_Z))
+    {
+        mContext->ErrorInvalidEnumInfo("framebufferTexture2D: texImageTarget:",
+                                       texImageTarget);
+        return;
+    }
+
+    // `texture`
+    if (tex) {
+        if (!mContext->ValidateObject("framebufferTexture2D: texture", *tex))
+            return;
+
+        if (!tex->HasEverBeenBound()) {
+            mContext->ErrorInvalidOperation("%s: `texture` has never been bound.",
+                                            funcName);
+            return;
+        }
+
+        const TexTarget destTexTarget = TexImageTargetToTexTarget(texImageTarget);
+        if (tex->Target() != destTexTarget) {
+            mContext->ErrorInvalidOperation("%s: Mismatched texture and texture target.",
+                                            funcName);
+            return;
+        }
+    }
+
+    // `level`
+    if (level < 0)
+        return mContext->ErrorInvalidValue("%s: `level` must not be negative.", funcName);
+
+    if (mContext->IsWebGL2()) {
+        /* GLES 3.0.4 p208:
+         *   If textarget is one of TEXTURE_CUBE_MAP_POSITIVE_X,
+         *   TEXTURE_CUBE_MAP_POSITIVE_Y, TEXTURE_CUBE_MAP_POSITIVE_Z,
+         *   TEXTURE_CUBE_MAP_NEGATIVE_X, TEXTURE_CUBE_MAP_NEGATIVE_Y,
+         *   or TEXTURE_CUBE_MAP_NEGATIVE_Z, then level must be greater
+         *   than or equal to zero and less than or equal to log2 of the
+         *   value of MAX_CUBE_MAP_TEXTURE_SIZE. If textarget is TEXTURE_2D,
+         *   level must be greater than or equal to zero and no larger than
+         *   log2 of the value of MAX_TEXTURE_SIZE. Otherwise, an
+         *   INVALID_VALUE error is generated.
+         */
+
+        if (texImageTarget == LOCAL_GL_TEXTURE_2D) {
+            if (uint32_t(level) > FloorLog2(mContext->mImplMaxTextureSize))
+                return mContext->ErrorInvalidValue("%s: `level` is too large.", funcName);
+        } else {
+            MOZ_ASSERT(texImageTarget >= LOCAL_GL_TEXTURE_CUBE_MAP_POSITIVE_X &&
+                       texImageTarget <= LOCAL_GL_TEXTURE_CUBE_MAP_NEGATIVE_Z);
+
+            if (uint32_t(level) > FloorLog2(mContext->mImplMaxCubeMapTextureSize))
+                return mContext->ErrorInvalidValue("%s: `level` is too large.", funcName);
+        }
+    } else if (level != 0) {
+        return mContext->ErrorInvalidValue("%s: `level` must be 0.", funcName);
+    }
+
+    // End of validation.
+
+    if (mContext->IsWebGL2() && attachEnum == LOCAL_GL_DEPTH_STENCIL_ATTACHMENT) {
+        mDepthAttachment.SetTexImage(tex, texImageTarget, level);
+        mStencilAttachment.SetTexImage(tex, texImageTarget, level);
+    } else {
+        attach->SetTexImage(tex, texImageTarget, level);
+    }
+
+    InvalidateFramebufferStatus();
+}
+
+void
+WebGLFramebuffer::FramebufferTextureLayer(const char* funcName, GLenum attachEnum,
+                                          WebGLTexture* tex, GLint level, GLint layer)
+{
+    MOZ_ASSERT(mContext->mBoundDrawFramebuffer == this ||
+               mContext->mBoundReadFramebuffer == this);
+
+    // `attachment`
+    const auto maybeAttach = GetAttachPoint(attachEnum);
+    if (!maybeAttach || !maybeAttach.value()) {
+        mContext->ErrorInvalidEnum("%s: Bad `attachment`: 0x%x.", funcName, attachEnum);
+        return;
+    }
+    const auto& attach = maybeAttach.value();
+
+    // `level`, `layer`
+    if (layer < 0)
+        return mContext->ErrorInvalidValue("%s: `layer` must be >= 0.", funcName);
+
+    if (level < 0)
+        return mContext->ErrorInvalidValue("%s: `level` must be >= 0.", funcName);
+
+    // `texture`
+    TexImageTarget texImageTarget = LOCAL_GL_TEXTURE_3D;
+    if (tex) {
+        if (!mContext->ValidateObject("framebufferTextureLayer: texture", *tex))
+            return;
+
+        if (!tex->HasEverBeenBound()) {
+            mContext->ErrorInvalidOperation("%s: `texture` has never been bound.",
+                                            funcName);
+            return;
+        }
+
+        texImageTarget = tex->Target().get();
+        switch (texImageTarget.get()) {
+        case LOCAL_GL_TEXTURE_3D:
+            if (uint32_t(layer) >= mContext->mImplMax3DTextureSize) {
+                mContext->ErrorInvalidValue("%s: `layer` must be < %s.", funcName,
+                                            "MAX_3D_TEXTURE_SIZE");
+                return;
+            }
+
+            if (uint32_t(level) > FloorLog2(mContext->mImplMax3DTextureSize)) {
+                mContext->ErrorInvalidValue("%s: `level` must be <= log2(%s).", funcName,
+                                            "MAX_3D_TEXTURE_SIZE");
+                return;
+            }
+            break;
+
+        case LOCAL_GL_TEXTURE_2D_ARRAY:
+            if (uint32_t(layer) >= mContext->mImplMaxArrayTextureLayers) {
+                mContext->ErrorInvalidValue("%s: `layer` must be < %s.", funcName,
+                                            "MAX_ARRAY_TEXTURE_LAYERS");
+                return;
+            }
+
+            if (uint32_t(level) > FloorLog2(mContext->mImplMaxTextureSize)) {
+                mContext->ErrorInvalidValue("%s: `level` must be <= log2(%s).", funcName,
+                                            "MAX_TEXTURE_SIZE");
+                return;
+            }
+            break;
+
+        default:
+            mContext->ErrorInvalidOperation("%s: `texture` must be a TEXTURE_3D or"
+                                            " TEXTURE_2D_ARRAY.",
+                                            funcName);
+            return;
+        }
+    }
+
+    // End of validation.
+
+    if (mContext->IsWebGL2() && attachEnum == LOCAL_GL_DEPTH_STENCIL_ATTACHMENT) {
+        mDepthAttachment.SetTexImage(tex, texImageTarget, level, layer);
+        mStencilAttachment.SetTexImage(tex, texImageTarget, level, layer);
+    } else {
+        attach->SetTexImage(tex, texImageTarget, level, layer);
+    }
+
+    InvalidateFramebufferStatus();
+}
+
+JS::Value
+WebGLFramebuffer::GetAttachmentParameter(const char* funcName, JSContext* cx,
+                                         GLenum target, GLenum attachEnum, GLenum pname,
+                                         ErrorResult* const out_error)
+{
+    const auto maybeAttach = GetAttachPoint(attachEnum);
+    if (!maybeAttach || attachEnum == LOCAL_GL_NONE) {
+        mContext->ErrorInvalidEnum("%s: Can only query COLOR_ATTACHMENTi,"
+                                   " DEPTH_ATTACHMENT, DEPTH_STENCIL_ATTACHMENT, or"
+                                   " STENCIL_ATTACHMENT for a framebuffer.",
+                                   funcName);
+        return JS::NullValue();
+    }
+    auto attach = maybeAttach.value();
+
+    if (mContext->IsWebGL2() && attachEnum == LOCAL_GL_DEPTH_STENCIL_ATTACHMENT) {
+        // There are a couple special rules for this one.
+
+        if (pname == LOCAL_GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE) {
+            mContext->ErrorInvalidOperation("%s: Querying"
+                                            " FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE"
+                                            " against DEPTH_STENCIL_ATTACHMENT is an"
+                                            " error.",
+                                            funcName);
+            return JS::NullValue();
+        }
+
+        if (mDepthAttachment.Renderbuffer() != mStencilAttachment.Renderbuffer() ||
+            mDepthAttachment.Texture() != mStencilAttachment.Texture())
+        {
+            mContext->ErrorInvalidOperation("%s: DEPTH_ATTACHMENT and STENCIL_ATTACHMENT"
+                                            " have different objects bound.",
+                                            funcName);
+            return JS::NullValue();
+        }
+
+        attach = &mDepthAttachment;
+    }
+
+    return attach->GetParameter(funcName, mContext, cx, target, attachEnum, pname,
+                                out_error);
+}
+
+////////////////////
+
+static void
+GetBackbufferFormats(const WebGLContext* webgl,
+                     const webgl::FormatInfo** const out_color,
+                     const webgl::FormatInfo** const out_depth,
+                     const webgl::FormatInfo** const out_stencil)
+{
+    const auto& options = webgl->Options();
+
+    const auto effFormat = (options.alpha ? webgl::EffectiveFormat::RGBA8
+                                          : webgl::EffectiveFormat::RGB8);
+    *out_color = webgl::GetFormat(effFormat);
+
+    *out_depth = nullptr;
+    *out_stencil = nullptr;
+    if (options.depth && options.stencil) {
+        *out_depth = webgl::GetFormat(webgl::EffectiveFormat::DEPTH24_STENCIL8);
+        *out_stencil = *out_depth;
+    } else {
+        if (options.depth) {
+            *out_depth = webgl::GetFormat(webgl::EffectiveFormat::DEPTH_COMPONENT16);
+        }
+        if (options.stencil) {
+            *out_stencil = webgl::GetFormat(webgl::EffectiveFormat::STENCIL_INDEX8);
+        }
+    }
+}
+
+/*static*/ void
+WebGLFramebuffer::BlitFramebuffer(WebGLContext* webgl,
+                                  const WebGLFramebuffer* srcFB, GLint srcX0, GLint srcY0,
+                                  GLint srcX1, GLint srcY1,
+                                  const WebGLFramebuffer* dstFB, GLint dstX0, GLint dstY0,
+                                  GLint dstX1, GLint dstY1,
+                                  GLbitfield mask, GLenum filter)
+{
+    const char funcName[] = "blitFramebuffer";
+    const auto& gl = webgl->gl;
+
+    ////
+    // Collect data
+
+    const auto fnGetDepthAndStencilAttach = [](const WebGLFramebuffer* fb,
+                                               const WebGLFBAttachPoint** const out_depth,
+                                               const WebGLFBAttachPoint** const out_stencil)
+    {
+        *out_depth = nullptr;
+        *out_stencil = nullptr;
+
+        if (!fb)
+            return;
+
+        if (fb->mDepthStencilAttachment.IsDefined()) {
+            *out_depth = *out_stencil = &fb->mDepthStencilAttachment;
+            return;
+        }
+        if (fb->mDepthAttachment.IsDefined()) {
+            *out_depth = &fb->mDepthAttachment;
+        }
+        if (fb->mStencilAttachment.IsDefined()) {
+            *out_stencil = &fb->mStencilAttachment;
+        }
+    };
+
+    const WebGLFBAttachPoint* srcDepthAttach;
+    const WebGLFBAttachPoint* srcStencilAttach;
+    fnGetDepthAndStencilAttach(srcFB, &srcDepthAttach, &srcStencilAttach);
+    const WebGLFBAttachPoint* dstDepthAttach;
+    const WebGLFBAttachPoint* dstStencilAttach;
+    fnGetDepthAndStencilAttach(dstFB, &dstDepthAttach, &dstStencilAttach);
+
+    ////
+
+    const auto fnGetFormat = [](const WebGLFBAttachPoint* cur,
+                                bool* const out_hasSamples) -> const webgl::FormatInfo*
+    {
+        if (!cur || !cur->IsDefined())
+            return nullptr;
+
+        *out_hasSamples |= bool(cur->Samples());
+        return cur->Format()->format;
+    };
+
+    const auto fnNarrowComponentType = [&](const webgl::FormatInfo* format) {
+        switch (format->componentType) {
+        case webgl::ComponentType::NormInt:
+        case webgl::ComponentType::NormUInt:
+            return webgl::ComponentType::Float;
+
+        default:
+            return format->componentType;
+        }
+    };
+
+    bool srcHasSamples;
+    const webgl::FormatInfo* srcColorFormat;
+    webgl::ComponentType srcColorType = webgl::ComponentType::None;
+    const webgl::FormatInfo* srcDepthFormat;
+    const webgl::FormatInfo* srcStencilFormat;
+
+    if (srcFB) {
+        srcHasSamples = false;
+        srcColorFormat = fnGetFormat(srcFB->mColorReadBuffer, &srcHasSamples);
+        srcDepthFormat = fnGetFormat(srcDepthAttach, &srcHasSamples);
+        srcStencilFormat = fnGetFormat(srcStencilAttach, &srcHasSamples);
+    } else {
+        srcHasSamples = false; // Always false.
+
+        GetBackbufferFormats(webgl, &srcColorFormat, &srcDepthFormat, &srcStencilFormat);
+    }
+
+    if (srcColorFormat) {
+        srcColorType = fnNarrowComponentType(srcColorFormat);
+    }
+
+    ////
+
+    bool dstHasSamples;
+    const webgl::FormatInfo* dstDepthFormat;
+    const webgl::FormatInfo* dstStencilFormat;
+    bool dstHasColor = false;
+    bool colorFormatsMatch = true;
+    bool colorTypesMatch = true;
+
+    const auto fnCheckColorFormat = [&](const webgl::FormatInfo* dstFormat) {
+        MOZ_ASSERT(dstFormat->r || dstFormat->g || dstFormat->b || dstFormat->a);
+        dstHasColor = true;
+        colorFormatsMatch &= (dstFormat == srcColorFormat);
+        colorTypesMatch &= ( fnNarrowComponentType(dstFormat) == srcColorType );
+    };
+
+    if (dstFB) {
+        dstHasSamples = false;
+
+        for (const auto& cur : dstFB->mColorDrawBuffers) {
+            const auto& format = fnGetFormat(cur, &dstHasSamples);
+            if (!format)
+                continue;
+
+            fnCheckColorFormat(format);
+        }
+
+        dstDepthFormat = fnGetFormat(dstDepthAttach, &dstHasSamples);
+        dstStencilFormat = fnGetFormat(dstStencilAttach, &dstHasSamples);
+    } else {
+        dstHasSamples = bool(gl->Screen()->Samples());
+
+        const webgl::FormatInfo* dstColorFormat;
+        GetBackbufferFormats(webgl, &dstColorFormat, &dstDepthFormat, &dstStencilFormat);
+
+        fnCheckColorFormat(dstColorFormat);
+    }
+
+    ////
+    // Clear unused buffer bits
+
+    if (mask & LOCAL_GL_COLOR_BUFFER_BIT &&
+        !srcColorFormat && !dstHasColor)
+    {
+        mask ^= LOCAL_GL_COLOR_BUFFER_BIT;
+    }
+
+    if (mask & LOCAL_GL_DEPTH_BUFFER_BIT &&
+        !srcDepthFormat && !dstDepthFormat)
+    {
+        mask ^= LOCAL_GL_DEPTH_BUFFER_BIT;
+    }
+
+    if (mask & LOCAL_GL_STENCIL_BUFFER_BIT &&
+        !srcStencilFormat && !dstStencilFormat)
+    {
+        mask ^= LOCAL_GL_STENCIL_BUFFER_BIT;
+    }
+
+    ////
+    // Validation
+
+    if (mask & LOCAL_GL_COLOR_BUFFER_BIT) {
+        if (srcColorFormat && filter == LOCAL_GL_LINEAR) {
+            const auto& type = srcColorFormat->componentType;
+            if (type == webgl::ComponentType::Int ||
+                type == webgl::ComponentType::UInt)
+            {
+                webgl->ErrorInvalidOperation("%s: `filter` is LINEAR and READ_BUFFER"
+                                             " contains integer data.",
+                                             funcName);
+                return;
+            }
+        }
+
+        if (!colorTypesMatch) {
+            webgl->ErrorInvalidOperation("%s: Color component types (fixed/float/uint/"
+                                         "int) must match.",
+                                         funcName);
+            return;
+        }
+    }
+
+    const GLbitfield depthAndStencilBits = LOCAL_GL_DEPTH_BUFFER_BIT |
+                                           LOCAL_GL_STENCIL_BUFFER_BIT;
+    if (bool(mask & depthAndStencilBits) &&
+        filter != LOCAL_GL_NEAREST)
+    {
+        webgl->ErrorInvalidOperation("%s: DEPTH_BUFFER_BIT and STENCIL_BUFFER_BIT can"
+                                     " only be used with NEAREST filtering.",
+                                     funcName);
+        return;
+    }
+
+    /* GLES 3.0.4, p199:
+     *   Calling BlitFramebuffer will result in an INVALID_OPERATION error if
+     *   mask includes DEPTH_BUFFER_BIT or STENCIL_BUFFER_BIT, and the source
+     *   and destination depth and stencil buffer formats do not match.
+     *
+     * jgilbert: The wording is such that if only DEPTH_BUFFER_BIT is specified,
+     * the stencil formats must match. This seems wrong. It could be a spec bug,
+     * or I could be missing an interaction in one of the earlier paragraphs.
+     */
+    if (mask & LOCAL_GL_DEPTH_BUFFER_BIT &&
+        dstDepthFormat && dstDepthFormat != srcDepthFormat)
+    {
+        webgl->ErrorInvalidOperation("%s: Depth buffer formats must match if selected.",
+                                     funcName);
+        return;
+    }
+
+    if (mask & LOCAL_GL_STENCIL_BUFFER_BIT &&
+        dstStencilFormat && dstStencilFormat != srcStencilFormat)
+    {
+        webgl->ErrorInvalidOperation("%s: Stencil buffer formats must match if selected.",
+                                     funcName);
+        return;
+    }
+
+    ////
+
+    if (dstHasSamples) {
+        webgl->ErrorInvalidOperation("%s: DRAW_FRAMEBUFFER may not have multiple"
+                                     " samples.",
+                                     funcName);
+        return;
+    }
+
+    if (srcHasSamples) {
+        if (mask & LOCAL_GL_COLOR_BUFFER_BIT &&
+            dstHasColor && !colorFormatsMatch)
+        {
+            webgl->ErrorInvalidOperation("%s: Color buffer formats must match if"
+                                         " selected, when reading from a multisampled"
+                                         " source.",
+                                         funcName);
+            return;
+        }
+
+        if (dstX0 != srcX0 ||
+            dstX1 != srcX1 ||
+            dstY0 != srcY0 ||
+            dstY1 != srcY1)
+        {
+            webgl->ErrorInvalidOperation("%s: If the source is multisampled, then the"
+                                         " source and dest regions must match exactly.",
+                                         funcName);
+            return;
+        }
+    }
+
+    ////
+    // Check for feedback
+
+    if (srcFB && dstFB) {
+        const WebGLFBAttachPoint* feedback = nullptr;
+
+        if (mask & LOCAL_GL_COLOR_BUFFER_BIT) {
+            MOZ_ASSERT(srcFB->mColorReadBuffer->IsDefined());
+            for (const auto& cur : dstFB->mColorDrawBuffers) {
+                if (srcFB->mColorReadBuffer->IsEquivalentForFeedback(*cur)) {
+                    feedback = cur;
+                    break;
+                }
+            }
+        }
+
+        if (mask & LOCAL_GL_DEPTH_BUFFER_BIT &&
+            srcDepthAttach->IsEquivalentForFeedback(*dstDepthAttach))
+        {
+            feedback = dstDepthAttach;
+        }
+
+        if (mask & LOCAL_GL_STENCIL_BUFFER_BIT &&
+            srcStencilAttach->IsEquivalentForFeedback(*dstStencilAttach))
+        {
+            feedback = dstStencilAttach;
+        }
+
+        if (feedback) {
+            webgl->ErrorInvalidOperation("%s: Feedback detected into DRAW_FRAMEBUFFER's"
+                                         " 0x%04x attachment.",
+                                         funcName, feedback->mAttachmentPoint);
+            return;
+        }
+    } else if (!srcFB && !dstFB) {
+        webgl->ErrorInvalidOperation("%s: Feedback with default framebuffer.", funcName);
+        return;
+    }
+
+    ////
+
+    gl->MakeCurrent();
+    webgl->OnBeforeReadCall();
+    WebGLContext::ScopedDrawCallWrapper wrapper(*webgl);
+    gl->fBlitFramebuffer(srcX0, srcY0, srcX1, srcY1,
+                         dstX0, dstY0, dstX1, dstY1,
+                         mask, filter);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// Goop.
+
+JSObject*
+WebGLFramebuffer::WrapObject(JSContext* cx, JS::Handle<JSObject*> givenProto)
+{
+    return dom::WebGLFramebufferBinding::Wrap(cx, this, givenProto);
+}
+
+inline void
+ImplCycleCollectionUnlink(mozilla::WebGLFBAttachPoint& field)
+{
+    field.Unlink();
+}
+
+inline void
+ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& callback,
+                            mozilla::WebGLFBAttachPoint& field,
+                            const char* name,
+                            uint32_t flags = 0)
+{
+    CycleCollectionNoteChild(callback, field.Texture(), name, flags);
+    CycleCollectionNoteChild(callback, field.Renderbuffer(), name, flags);
+}
+
+template<typename C>
+inline void
+ImplCycleCollectionUnlink(C& field)
+{
+    for (auto& cur : field) {
+        cur.Unlink();
+    }
+}
+
+template<typename C>
+inline void
+ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& callback,
+                            C& field,
+                            const char* name,
+                            uint32_t flags = 0)
+{
+    for (auto& cur : field) {
+        ImplCycleCollectionTraverse(callback, cur, name, flags);
+    }
+}
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(WebGLFramebuffer,
+                                      mDepthAttachment,
+                                      mStencilAttachment,
+                                      mDepthStencilAttachment,
+                                      mColorAttachments)
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(WebGLFramebuffer, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(WebGLFramebuffer, Release)
+
+} // namespace mozilla