The Tor Browser: gfx/2d/PathCairo.cpp@97036ab72558 (annotated)

gfx/2d/PathCairo.cpp@97036ab72558 (annotated)

gfx/2d/PathCairo.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: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "PathCairo.h"
 #include <math.h>
 #include "DrawTargetCairo.h"
 #include "Logging.h"
 #include "PathHelpers.h"
 #include "HelpersCairo.h"
 namespace mozilla {
 namespace gfx {
 PathBuilderCairo::PathBuilderCairo(FillRule aFillRule)
   : mFillRule(aFillRule)
 {
 }
 void
 PathBuilderCairo::MoveTo(const Point &aPoint)
 {
   cairo_path_data_t data;
   data.header.type = CAIRO_PATH_MOVE_TO;
   data.header.length = 2;
   mPathData.push_back(data);
   data.point.x = aPoint.x;
   data.point.y = aPoint.y;
   mPathData.push_back(data);
   mBeginPoint = mCurrentPoint = aPoint;
 }
 void
 PathBuilderCairo::LineTo(const Point &aPoint)
 {
   cairo_path_data_t data;
   data.header.type = CAIRO_PATH_LINE_TO;
   data.header.length = 2;
   mPathData.push_back(data);
   data.point.x = aPoint.x;
   data.point.y = aPoint.y;
   mPathData.push_back(data);
   mCurrentPoint = aPoint;
 }
 void
 PathBuilderCairo::BezierTo(const Point &aCP1,
                            const Point &aCP2,
                            const Point &aCP3)
 {
   cairo_path_data_t data;
   data.header.type = CAIRO_PATH_CURVE_TO;
   data.header.length = 4;
   mPathData.push_back(data);
   data.point.x = aCP1.x;
   data.point.y = aCP1.y;
   mPathData.push_back(data);
   data.point.x = aCP2.x;
   data.point.y = aCP2.y;
   mPathData.push_back(data);
   data.point.x = aCP3.x;
   data.point.y = aCP3.y;
   mPathData.push_back(data);
   mCurrentPoint = aCP3;
 }
 void
 PathBuilderCairo::QuadraticBezierTo(const Point &aCP1,
                                     const Point &aCP2)
 {
   // We need to elevate the degree of this quadratic Bézier to cubic, so we're
   // going to add an intermediate control point, and recompute control point 1.
   // The first and last control points remain the same.
   // This formula can be found on http://fontforge.sourceforge.net/bezier.html
   Point CP0 = CurrentPoint();
   Point CP1 = (CP0 + aCP1 * 2.0) / 3.0;
   Point CP2 = (aCP2 + aCP1 * 2.0) / 3.0;
   Point CP3 = aCP2;
   cairo_path_data_t data;
   data.header.type = CAIRO_PATH_CURVE_TO;
   data.header.length = 4;
   mPathData.push_back(data);
   data.point.x = CP1.x;
   data.point.y = CP1.y;
   mPathData.push_back(data);
   data.point.x = CP2.x;
   data.point.y = CP2.y;
   mPathData.push_back(data);
   data.point.x = CP3.x;
   data.point.y = CP3.y;
   mPathData.push_back(data);
   mCurrentPoint = aCP2;
 }
 void
 PathBuilderCairo::Close()
 {
   cairo_path_data_t data;
   data.header.type = CAIRO_PATH_CLOSE_PATH;
   data.header.length = 1;
   mPathData.push_back(data);
   mCurrentPoint = mBeginPoint;
 }
 void
 PathBuilderCairo::Arc(const Point &aOrigin, float aRadius, float aStartAngle,
                      float aEndAngle, bool aAntiClockwise)
 {
   ArcToBezier(this, aOrigin, Size(aRadius, aRadius), aStartAngle, aEndAngle, aAntiClockwise);
 }
 Point
 PathBuilderCairo::CurrentPoint() const
 {
   return mCurrentPoint;
 }
 TemporaryRef<Path>
 PathBuilderCairo::Finish()
 {
   return new PathCairo(mFillRule, mPathData, mCurrentPoint);
 }
 PathCairo::PathCairo(FillRule aFillRule, std::vector<cairo_path_data_t> &aPathData, const Point &aCurrentPoint)
   : mFillRule(aFillRule)
   , mContainingContext(nullptr)
   , mCurrentPoint(aCurrentPoint)
 {
   mPathData.swap(aPathData);
 }
 PathCairo::PathCairo(cairo_t *aContext)
   : mFillRule(FillRule::FILL_WINDING)
   , mContainingContext(nullptr)
 {
   cairo_path_t *path = cairo_copy_path(aContext);
   // XXX - mCurrentPoint is not properly set here, the same is true for the
   // D2D Path code, we never require current point when hitting this codepath
   // but this should be fixed.
   for (int i = 0; i < path->num_data; i++) {
     mPathData.push_back(path->data[i]);
   }
   cairo_path_destroy(path);
 }
 PathCairo::~PathCairo()
 {
   if (mContainingContext) {
     cairo_destroy(mContainingContext);
   }
 }
 TemporaryRef<PathBuilder>
 PathCairo::CopyToBuilder(FillRule aFillRule) const
 {
   RefPtr<PathBuilderCairo> builder = new PathBuilderCairo(aFillRule);
   builder->mPathData = mPathData;
   builder->mCurrentPoint = mCurrentPoint;
   return builder;
 }
 TemporaryRef<PathBuilder>
 PathCairo::TransformedCopyToBuilder(const Matrix &aTransform, FillRule aFillRule) const
 {
   RefPtr<PathBuilderCairo> builder = new PathBuilderCairo(aFillRule);
   AppendPathToBuilder(builder, &aTransform);
   builder->mCurrentPoint = aTransform * mCurrentPoint;
   return builder;
 }
 bool
 PathCairo::ContainsPoint(const Point &aPoint, const Matrix &aTransform) const
 {
   Matrix inverse = aTransform;
   inverse.Invert();
   Point transformed = inverse * aPoint;
   EnsureContainingContext();
   return cairo_in_fill(mContainingContext, transformed.x, transformed.y);
 }
 bool
 PathCairo::StrokeContainsPoint(const StrokeOptions &aStrokeOptions,
                                const Point &aPoint,
                                const Matrix &aTransform) const
 {
   Matrix inverse = aTransform;
   inverse.Invert();
   Point transformed = inverse * aPoint;
   EnsureContainingContext();
   SetCairoStrokeOptions(mContainingContext, aStrokeOptions);
   return cairo_in_stroke(mContainingContext, transformed.x, transformed.y);
 }
 Rect
 PathCairo::GetBounds(const Matrix &aTransform) const
 {
   EnsureContainingContext();
   double x1, y1, x2, y2;
   cairo_path_extents(mContainingContext, &x1, &y1, &x2, &y2);
   Rect bounds(Float(x1), Float(y1), Float(x2 - x1), Float(y2 - y1));
   return aTransform.TransformBounds(bounds);
 }
 Rect
 PathCairo::GetStrokedBounds(const StrokeOptions &aStrokeOptions,
                             const Matrix &aTransform) const
 {
   EnsureContainingContext();
   double x1, y1, x2, y2;
   SetCairoStrokeOptions(mContainingContext, aStrokeOptions);
   cairo_stroke_extents(mContainingContext, &x1, &y1, &x2, &y2);
   Rect bounds((Float)x1, (Float)y1, (Float)(x2 - x1), (Float)(y2 - y1));
   return aTransform.TransformBounds(bounds);
 }
 void
 PathCairo::StreamToSink(PathSink *aSink) const
 {
   for (size_t i = 0; i < mPathData.size(); i++) {
     switch (mPathData[i].header.type) {
     case CAIRO_PATH_MOVE_TO:
       i++;
       aSink->MoveTo(Point(mPathData[i].point.x, mPathData[i].point.y));
       break;
     case CAIRO_PATH_LINE_TO:
       i++;
       aSink->LineTo(Point(mPathData[i].point.x, mPathData[i].point.y));
       break;
     case CAIRO_PATH_CURVE_TO:
       aSink->BezierTo(Point(mPathData[i + 1].point.x, mPathData[i + 1].point.y),
                       Point(mPathData[i + 2].point.x, mPathData[i + 2].point.y),
                       Point(mPathData[i + 3].point.x, mPathData[i + 3].point.y));
       i += 3;
       break;
     case CAIRO_PATH_CLOSE_PATH:
       aSink->Close();
       break;
     default:
       // Corrupt path data!
       MOZ_ASSERT(false);
     }
   }
 }
 void
 PathCairo::EnsureContainingContext() const
 {
   if (mContainingContext) {
     return;
   }
   mContainingContext = cairo_create(DrawTargetCairo::GetDummySurface());
   SetPathOnContext(mContainingContext);
 }
 void
 PathCairo::SetPathOnContext(cairo_t *aContext) const
 {
   // Needs the correct fill rule set.
   cairo_set_fill_rule(aContext, GfxFillRuleToCairoFillRule(mFillRule));
   cairo_new_path(aContext);
   if (mPathData.size()) {
     cairo_path_t path;
     path.data = const_cast<cairo_path_data_t*>(&mPathData.front());
     path.num_data = mPathData.size();
     path.status = CAIRO_STATUS_SUCCESS;
     cairo_append_path(aContext, &path);
   }
 }
 void
 PathCairo::AppendPathToBuilder(PathBuilderCairo *aBuilder, const Matrix *aTransform) const
 {
   if (aTransform) {
     size_t i = 0;
     while (i < mPathData.size()) {
       uint32_t pointCount = mPathData[i].header.length - 1;
       aBuilder->mPathData.push_back(mPathData[i]);
       i++;
       for (uint32_t c = 0; c < pointCount; c++) {
         cairo_path_data_t data;
         Point newPoint = *aTransform * Point(mPathData[i].point.x, mPathData[i].point.y);
         data.point.x = newPoint.x;
         data.point.y = newPoint.y;
         aBuilder->mPathData.push_back(data);
         i++;
       }
     }
   } else {
     for (size_t i = 0; i < mPathData.size(); i++) {
       aBuilder->mPathData.push_back(mPathData[i]);
     }
   }
 }
 }
 }

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gfx/2d/PathCairo.cpp@97036ab72558 (annotated)

gfx/2d/PathCairo.cpp