The Tor Browser: gfx/thebes/gfxBlur.cpp@97036ab72558 (annotated)

gfx/thebes/gfxBlur.cpp@97036ab72558 (annotated)

gfx/thebes/gfxBlur.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- Mode: C++; tab-width: 4; 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 "gfxBlur.h"
 #include "gfxContext.h"
 #include "gfxImageSurface.h"
 #include "gfxPlatform.h"
 #include "mozilla/gfx/Blur.h"
 #include "mozilla/gfx/2D.h"
 using namespace mozilla::gfx;
 gfxAlphaBoxBlur::gfxAlphaBoxBlur()
  : mBlur(nullptr)
 {
 }
 gfxAlphaBoxBlur::~gfxAlphaBoxBlur()
 {
   mContext = nullptr;
   delete mBlur;
 }
 gfxContext*
 gfxAlphaBoxBlur::Init(const gfxRect& aRect,
                       const gfxIntSize& aSpreadRadius,
                       const gfxIntSize& aBlurRadius,
                       const gfxRect* aDirtyRect,
                       const gfxRect* aSkipRect)
 {
     mozilla::gfx::Rect rect(Float(aRect.x), Float(aRect.y),
                             Float(aRect.width), Float(aRect.height));
     IntSize spreadRadius(aSpreadRadius.width, aSpreadRadius.height);
     IntSize blurRadius(aBlurRadius.width, aBlurRadius.height);
     nsAutoPtr<mozilla::gfx::Rect> dirtyRect;
     if (aDirtyRect) {
       dirtyRect = new mozilla::gfx::Rect(Float(aDirtyRect->x),
                                          Float(aDirtyRect->y),
                                          Float(aDirtyRect->width),
                                          Float(aDirtyRect->height));
     }
     nsAutoPtr<mozilla::gfx::Rect> skipRect;
     if (aSkipRect) {
       skipRect = new mozilla::gfx::Rect(Float(aSkipRect->x),
                                         Float(aSkipRect->y),
                                         Float(aSkipRect->width),
                                         Float(aSkipRect->height));
     }
     mBlur = new AlphaBoxBlur(rect, spreadRadius, blurRadius, dirtyRect, skipRect);
     size_t blurDataSize = mBlur->GetSurfaceAllocationSize();
     if (blurDataSize == 0)
         return nullptr;
     IntSize size = mBlur->GetSize();
     // Make an alpha-only surface to draw on. We will play with the data after
     // everything is drawn to create a blur effect.
     mData = new (std::nothrow) unsigned char[blurDataSize];
     if (!mData) {
         return nullptr;
     }
     memset(mData, 0, blurDataSize);
     mozilla::RefPtr<DrawTarget> dt =
         gfxPlatform::GetPlatform()->CreateDrawTargetForData(mData, size,
                                                             mBlur->GetStride(),
                                                             SurfaceFormat::A8);
     if (!dt) {
         nsRefPtr<gfxImageSurface> image =
             new gfxImageSurface(mData,
                                 gfxIntSize(size.width, size.height),
                                 mBlur->GetStride(),
                                 gfxImageFormat::A8);
         dt = Factory::CreateDrawTargetForCairoSurface(image->CairoSurface(), size);
         if (!dt) {
             return nullptr;
         }
     }
     IntRect irect = mBlur->GetRect();
     gfxPoint topleft(irect.TopLeft().x, irect.TopLeft().y);
     mContext = new gfxContext(dt);
     mContext->Translate(-topleft);
     return mContext;
 }
 void
 gfxAlphaBoxBlur::Paint(gfxContext* aDestinationCtx)
 {
     if (!mContext)
         return;
     mBlur->Blur(mData);
     mozilla::gfx::Rect* dirtyRect = mBlur->GetDirtyRect();
     DrawTarget *dest = aDestinationCtx->GetDrawTarget();
     if (!dest) {
       NS_WARNING("Blurring not supported for Thebes contexts!");
       return;
     }
     mozilla::RefPtr<SourceSurface> mask
       = dest->CreateSourceSurfaceFromData(mData,
                                           mBlur->GetSize(),
                                           mBlur->GetStride(),
                                           SurfaceFormat::A8);
     if (!mask) {
       NS_ERROR("Failed to create mask!");
       return;
     }
     nsRefPtr<gfxPattern> thebesPat = aDestinationCtx->GetPattern();
     Pattern* pat = thebesPat->GetPattern(dest, nullptr);
     Matrix oldTransform = dest->GetTransform();
     Matrix newTransform = oldTransform;
     newTransform.Translate(mBlur->GetRect().x, mBlur->GetRect().y);
     // Avoid a semi-expensive clip operation if we can, otherwise
     // clip to the dirty rect
     if (dirtyRect) {
         dest->PushClipRect(*dirtyRect);
     }
     dest->SetTransform(newTransform);
     dest->MaskSurface(*pat, mask, Point(0, 0));
     dest->SetTransform(oldTransform);
     if (dirtyRect) {
         dest->PopClip();
     }
 }
 gfxIntSize gfxAlphaBoxBlur::CalculateBlurRadius(const gfxPoint& aStd)
 {
     mozilla::gfx::Point std(Float(aStd.x), Float(aStd.y));
     IntSize size = AlphaBoxBlur::CalculateBlurRadius(std);
     return gfxIntSize(size.width, size.height);
 }
 /* static */ void
 gfxAlphaBoxBlur::BlurRectangle(gfxContext *aDestinationCtx,
                                const gfxRect& aRect,
                                gfxCornerSizes* aCornerRadii,
                                const gfxPoint& aBlurStdDev,
                                const gfxRGBA& aShadowColor,
                                const gfxRect& aDirtyRect,
                                const gfxRect& aSkipRect)
 {
   gfxIntSize blurRadius = CalculateBlurRadius(aBlurStdDev);
   // Create the temporary surface for blurring
   gfxAlphaBoxBlur blur;
   gfxContext *dest = blur.Init(aRect, gfxIntSize(), blurRadius, &aDirtyRect, &aSkipRect);
   if (!dest) {
     return;
   }
   gfxRect shadowGfxRect = aRect;
   shadowGfxRect.Round();
   dest->NewPath();
   if (aCornerRadii) {
     dest->RoundedRectangle(shadowGfxRect, *aCornerRadii);
   } else {
     dest->Rectangle(shadowGfxRect);
   }
   dest->Fill();
   aDestinationCtx->SetColor(aShadowColor);
   blur.Paint(aDestinationCtx);
 }

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gfx/thebes/gfxBlur.cpp@97036ab72558 (annotated)

gfx/thebes/gfxBlur.cpp