layout/svg/DisplaySVGItem.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 // Main header first:
   8 #include "DisplaySVGItem.h"
   9
  10 #include "mozilla/ISVGDisplayableFrame.h"
  11 #include "mozilla/SVGUtils.h"
  12 #include "nsLayoutUtils.h"
  13 #include "nsPoint.h"
  14
  15 using namespace mozilla::gfx;
  16 using namespace mozilla::image;
  17
  18 namespace mozilla {
  19
  20 void DisplaySVGItem::HitTest(nsDisplayListBuilder* aBuilder,
  21                              const nsRect& aRect, HitTestState* aState,
  22                              nsTArray<nsIFrame*>* aOutFrames) {
  23   ISVGDisplayableFrame* svgFrame = do_QueryFrame(mFrame);
  24   MOZ_ASSERT(svgFrame, "Unexpected frame type");
  25
  26   nsPoint pointRelativeToReferenceFrame = aRect.Center();
  27   // ToReferenceFrame() includes mFrame->GetPosition(), our user
  28   // space position.
  29   nsPoint userSpacePtInAppUnits = pointRelativeToReferenceFrame -
  30                                   (ToReferenceFrame() - mFrame->GetPosition());
  31   gfxPoint userSpacePt =
  32       gfxPoint(userSpacePtInAppUnits.x, userSpacePtInAppUnits.y) /
  33       AppUnitsPerCSSPixel();
  34   if (auto* target = svgFrame->GetFrameForPoint(userSpacePt)) {
  35     aOutFrames->AppendElement(target);
  36   }
  37 }
  38
  39 void DisplaySVGItem::Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) {
  40   ISVGDisplayableFrame* svgFrame = do_QueryFrame(mFrame);
  41   MOZ_ASSERT(svgFrame, "Unexpected frame type");
  42   int32_t appUnitsPerDevPixel = mFrame->PresContext()->AppUnitsPerDevPixel();
  43
  44   // ToReferenceFrame() includes our mRect offset, but painting takes
  45   // account of that too. To avoid double counting, we subtract that
  46   // here.
  47   nsPoint offset = ToReferenceFrame() - mFrame->GetPosition();
  48
  49   gfxPoint devPixelOffset =
  50       nsLayoutUtils::PointToGfxPoint(offset, appUnitsPerDevPixel);
  51
  52   gfxMatrix tm = SVGUtils::GetCSSPxToDevPxMatrix(mFrame) *
  53                  gfxMatrix::Translation(devPixelOffset);
  54   imgDrawingParams imgParams(aBuilder->GetImageDecodeFlags());
  55   svgFrame->PaintSVG(*aCtx, tm, imgParams);
  56 }
  57
  58 }  // namespace mozilla