michael@0: /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "DisplayItemClip.h"
michael@0: 
michael@0: #include "gfxContext.h"
michael@0: #include "nsPresContext.h"
michael@0: #include "nsCSSRendering.h"
michael@0: #include "nsLayoutUtils.h"
michael@0: #include "nsRegion.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: void
michael@0: DisplayItemClip::SetTo(const nsRect& aRect)
michael@0: {
michael@0:   mHaveClipRect = true;
michael@0:   mClipRect = aRect;
michael@0:   mRoundedClipRects.Clear();
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::SetTo(const nsRect& aRect, const nscoord* aRadii)
michael@0: {
michael@0:   mHaveClipRect = true;
michael@0:   mClipRect = aRect;
michael@0:   mRoundedClipRects.SetLength(1);
michael@0:   mRoundedClipRects[0].mRect = aRect;
michael@0:   memcpy(mRoundedClipRects[0].mRadii, aRadii, sizeof(nscoord)*8);
michael@0: }
michael@0: 
michael@0: bool
michael@0: DisplayItemClip::MayIntersect(const nsRect& aRect) const
michael@0: {
michael@0:   if (!mHaveClipRect) {
michael@0:     return !aRect.IsEmpty();
michael@0:   }
michael@0:   nsRect r = aRect.Intersect(mClipRect);
michael@0:   if (r.IsEmpty()) {
michael@0:     return false;
michael@0:   }
michael@0:   for (uint32_t i = 0; i < mRoundedClipRects.Length(); ++i) {
michael@0:     const RoundedRect& rr = mRoundedClipRects[i];
michael@0:     if (!nsLayoutUtils::RoundedRectIntersectsRect(rr.mRect, rr.mRadii, r)) {
michael@0:       return false;
michael@0:     }
michael@0:   }
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::IntersectWith(const DisplayItemClip& aOther)
michael@0: {
michael@0:   if (!aOther.mHaveClipRect) {
michael@0:     return;
michael@0:   }
michael@0:   if (!mHaveClipRect) {
michael@0:     *this = aOther;
michael@0:     return;
michael@0:   }
michael@0:   if (!mClipRect.IntersectRect(mClipRect, aOther.mClipRect)) {
michael@0:     mRoundedClipRects.Clear();
michael@0:     return;
michael@0:   }
michael@0:   mRoundedClipRects.AppendElements(aOther.mRoundedClipRects);
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::ApplyTo(gfxContext* aContext,
michael@0:                          nsPresContext* aPresContext,
michael@0:                          uint32_t aBegin, uint32_t aEnd)
michael@0: {
michael@0:   int32_t A2D = aPresContext->AppUnitsPerDevPixel();
michael@0:   ApplyRectTo(aContext, A2D);
michael@0:   ApplyRoundedRectsTo(aContext, A2D, aBegin, aEnd);
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::ApplyRectTo(gfxContext* aContext, int32_t A2D) const
michael@0: {
michael@0:   aContext->NewPath();
michael@0:   gfxRect clip = nsLayoutUtils::RectToGfxRect(mClipRect, A2D);
michael@0:   aContext->Rectangle(clip, true);
michael@0:   aContext->Clip();
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::ApplyRoundedRectsTo(gfxContext* aContext,
michael@0:                                      int32_t A2D,
michael@0:                                      uint32_t aBegin, uint32_t aEnd) const
michael@0: {
michael@0:   aEnd = std::min<uint32_t>(aEnd, mRoundedClipRects.Length());
michael@0: 
michael@0:   for (uint32_t i = aBegin; i < aEnd; ++i) {
michael@0:     AddRoundedRectPathTo(aContext, A2D, mRoundedClipRects[i]);
michael@0:     aContext->Clip();
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::DrawRoundedRectsTo(gfxContext* aContext,
michael@0:                                     int32_t A2D,
michael@0:                                     uint32_t aBegin, uint32_t aEnd) const
michael@0: {
michael@0:   aEnd = std::min<uint32_t>(aEnd, mRoundedClipRects.Length());
michael@0: 
michael@0:   if (aEnd - aBegin == 0)
michael@0:     return;
michael@0: 
michael@0:   // If there is just one rounded rect we can just fill it, if there are more then we
michael@0:   // must clip the rest to get the intersection of clips
michael@0:   ApplyRoundedRectsTo(aContext, A2D, aBegin, aEnd - 1);
michael@0:   AddRoundedRectPathTo(aContext, A2D, mRoundedClipRects[aEnd - 1]);
michael@0:   aContext->Fill();
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::AddRoundedRectPathTo(gfxContext* aContext,
michael@0:                                       int32_t A2D,
michael@0:                                       const RoundedRect &aRoundRect) const
michael@0: {
michael@0:   gfxCornerSizes pixelRadii;
michael@0:   nsCSSRendering::ComputePixelRadii(aRoundRect.mRadii, A2D, &pixelRadii);
michael@0: 
michael@0:   gfxRect clip = nsLayoutUtils::RectToGfxRect(aRoundRect.mRect, A2D);
michael@0:   clip.Round();
michael@0:   clip.Condition();
michael@0: 
michael@0:   aContext->NewPath();
michael@0:   aContext->RoundedRectangle(clip, pixelRadii);
michael@0: }
michael@0: 
michael@0: nsRect
michael@0: DisplayItemClip::ApproximateIntersectInward(const nsRect& aRect) const
michael@0: {
michael@0:   nsRect r = aRect;
michael@0:   if (mHaveClipRect) {
michael@0:     r.IntersectRect(r, mClipRect);
michael@0:   }
michael@0:   for (uint32_t i = 0, iEnd = mRoundedClipRects.Length();
michael@0:        i < iEnd; ++i) {
michael@0:     const RoundedRect &rr = mRoundedClipRects[i];
michael@0:     nsRegion rgn = nsLayoutUtils::RoundedRectIntersectRect(rr.mRect, rr.mRadii, r);
michael@0:     r = rgn.GetLargestRectangle();
michael@0:   }
michael@0:   return r;
michael@0: }
michael@0: 
michael@0: // Test if (aXPoint, aYPoint) is in the ellipse with center (aXCenter, aYCenter)
michael@0: // and radii aXRadius, aYRadius.
michael@0: bool IsInsideEllipse(nscoord aXRadius, nscoord aXCenter, nscoord aXPoint,
michael@0:                      nscoord aYRadius, nscoord aYCenter, nscoord aYPoint)
michael@0: {
michael@0:   float scaledX = float(aXPoint - aXCenter) / float(aXRadius);
michael@0:   float scaledY = float(aYPoint - aYCenter) / float(aYRadius);
michael@0:   return scaledX * scaledX + scaledY * scaledY < 1.0f;
michael@0: }
michael@0: 
michael@0: bool
michael@0: DisplayItemClip::IsRectClippedByRoundedCorner(const nsRect& aRect) const
michael@0: {
michael@0:   if (mRoundedClipRects.IsEmpty())
michael@0:     return false;
michael@0: 
michael@0:   nsRect rect;
michael@0:   rect.IntersectRect(aRect, NonRoundedIntersection());
michael@0:   for (uint32_t i = 0, iEnd = mRoundedClipRects.Length();
michael@0:        i < iEnd; ++i) {
michael@0:     const RoundedRect &rr = mRoundedClipRects[i];
michael@0:     // top left
michael@0:     if (rect.x < rr.mRect.x + rr.mRadii[NS_CORNER_TOP_LEFT_X] &&
michael@0:         rect.y < rr.mRect.y + rr.mRadii[NS_CORNER_TOP_LEFT_Y]) {
michael@0:       if (!IsInsideEllipse(rr.mRadii[NS_CORNER_TOP_LEFT_X],
michael@0:                            rr.mRect.x + rr.mRadii[NS_CORNER_TOP_LEFT_X],
michael@0:                            rect.x,
michael@0:                            rr.mRadii[NS_CORNER_TOP_LEFT_Y],
michael@0:                            rr.mRect.y + rr.mRadii[NS_CORNER_TOP_LEFT_Y],
michael@0:                            rect.y)) {
michael@0:         return true;
michael@0:       }
michael@0:     }
michael@0:     // top right
michael@0:     if (rect.XMost() > rr.mRect.XMost() - rr.mRadii[NS_CORNER_TOP_RIGHT_X] &&
michael@0:         rect.y < rr.mRect.y + rr.mRadii[NS_CORNER_TOP_RIGHT_Y]) {
michael@0:       if (!IsInsideEllipse(rr.mRadii[NS_CORNER_TOP_RIGHT_X],
michael@0:                            rr.mRect.XMost() - rr.mRadii[NS_CORNER_TOP_RIGHT_X],
michael@0:                            rect.XMost(),
michael@0:                            rr.mRadii[NS_CORNER_TOP_RIGHT_Y],
michael@0:                            rr.mRect.y + rr.mRadii[NS_CORNER_TOP_RIGHT_Y],
michael@0:                            rect.y)) {
michael@0:         return true;
michael@0:       }
michael@0:     }
michael@0:     // bottom left
michael@0:     if (rect.x < rr.mRect.x + rr.mRadii[NS_CORNER_BOTTOM_LEFT_X] &&
michael@0:         rect.YMost() > rr.mRect.YMost() - rr.mRadii[NS_CORNER_BOTTOM_LEFT_Y]) {
michael@0:       if (!IsInsideEllipse(rr.mRadii[NS_CORNER_BOTTOM_LEFT_X],
michael@0:                            rr.mRect.x + rr.mRadii[NS_CORNER_BOTTOM_LEFT_X],
michael@0:                            rect.x,
michael@0:                            rr.mRadii[NS_CORNER_BOTTOM_LEFT_Y],
michael@0:                            rr.mRect.YMost() - rr.mRadii[NS_CORNER_BOTTOM_LEFT_Y],
michael@0:                            rect.YMost())) {
michael@0:         return true;
michael@0:       }
michael@0:     }
michael@0:     // bottom right
michael@0:     if (rect.XMost() > rr.mRect.XMost() - rr.mRadii[NS_CORNER_BOTTOM_RIGHT_X] &&
michael@0:         rect.YMost() > rr.mRect.YMost() - rr.mRadii[NS_CORNER_BOTTOM_RIGHT_Y]) {
michael@0:       if (!IsInsideEllipse(rr.mRadii[NS_CORNER_BOTTOM_RIGHT_X],
michael@0:                            rr.mRect.XMost() - rr.mRadii[NS_CORNER_BOTTOM_RIGHT_X],
michael@0:                            rect.XMost(),
michael@0:                            rr.mRadii[NS_CORNER_BOTTOM_RIGHT_Y],
michael@0:                            rr.mRect.YMost() - rr.mRadii[NS_CORNER_BOTTOM_RIGHT_Y],
michael@0:                            rect.YMost())) {
michael@0:         return true;
michael@0:       }
michael@0:     }
michael@0:   }
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: nsRect
michael@0: DisplayItemClip::NonRoundedIntersection() const
michael@0: {
michael@0:   NS_ASSERTION(mHaveClipRect, "Must have a clip rect!");
michael@0:   nsRect result = mClipRect;
michael@0:   for (uint32_t i = 0, iEnd = mRoundedClipRects.Length();
michael@0:        i < iEnd; ++i) {
michael@0:     result.IntersectRect(result, mRoundedClipRects[i].mRect);
michael@0:   }
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: bool
michael@0: DisplayItemClip::IsRectAffectedByClip(const nsRect& aRect) const
michael@0: {
michael@0:   if (mHaveClipRect && !mClipRect.Contains(aRect)) {
michael@0:     return true;
michael@0:   }
michael@0:   for (uint32_t i = 0, iEnd = mRoundedClipRects.Length();
michael@0:        i < iEnd; ++i) {
michael@0:     const RoundedRect &rr = mRoundedClipRects[i];
michael@0:     nsRegion rgn = nsLayoutUtils::RoundedRectIntersectRect(rr.mRect, rr.mRadii, aRect);
michael@0:     if (!rgn.Contains(aRect)) {
michael@0:       return true;
michael@0:     }
michael@0:   }
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: nsRect
michael@0: DisplayItemClip::ApplyNonRoundedIntersection(const nsRect& aRect) const
michael@0: {
michael@0:   if (!mHaveClipRect) {
michael@0:     return aRect;
michael@0:   }
michael@0: 
michael@0:   nsRect result = aRect.Intersect(mClipRect);
michael@0:   for (uint32_t i = 0, iEnd = mRoundedClipRects.Length();
michael@0:        i < iEnd; ++i) {
michael@0:     result.Intersect(mRoundedClipRects[i].mRect);
michael@0:   }
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::RemoveRoundedCorners()
michael@0: {
michael@0:   if (mRoundedClipRects.IsEmpty())
michael@0:     return;
michael@0: 
michael@0:   mClipRect = NonRoundedIntersection();
michael@0:   mRoundedClipRects.Clear();
michael@0: }
michael@0: 
michael@0: static void
michael@0: AccumulateRectDifference(const nsRect& aR1, const nsRect& aR2, nsRegion* aOut)
michael@0: {
michael@0:   if (aR1.IsEqualInterior(aR2))
michael@0:     return;
michael@0:   nsRegion r;
michael@0:   r.Xor(aR1, aR2);
michael@0:   aOut->Or(*aOut, r);
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::AddOffsetAndComputeDifference(const nsPoint& aOffset,
michael@0:                                                const nsRect& aBounds,
michael@0:                                                const DisplayItemClip& aOther,
michael@0:                                                const nsRect& aOtherBounds,
michael@0:                                                nsRegion* aDifference)
michael@0: {
michael@0:   if (mHaveClipRect != aOther.mHaveClipRect ||
michael@0:       mRoundedClipRects.Length() != aOther.mRoundedClipRects.Length()) {
michael@0:     aDifference->Or(*aDifference, aBounds);
michael@0:     aDifference->Or(*aDifference, aOtherBounds);
michael@0:     return;
michael@0:   }
michael@0:   if (mHaveClipRect) {
michael@0:     AccumulateRectDifference((mClipRect + aOffset).Intersect(aBounds),
michael@0:                              aOther.mClipRect.Intersect(aOtherBounds),
michael@0:                              aDifference);
michael@0:   }
michael@0:   for (uint32_t i = 0; i < mRoundedClipRects.Length(); ++i) {
michael@0:     if (mRoundedClipRects[i] + aOffset != aOther.mRoundedClipRects[i]) {
michael@0:       // The corners make it tricky so we'll just add both rects here.
michael@0:       aDifference->Or(*aDifference, mRoundedClipRects[i].mRect.Intersect(aBounds));
michael@0:       aDifference->Or(*aDifference, aOther.mRoundedClipRects[i].mRect.Intersect(aOtherBounds));
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: uint32_t
michael@0: DisplayItemClip::GetCommonRoundedRectCount(const DisplayItemClip& aOther,
michael@0:                                            uint32_t aMax) const
michael@0: {
michael@0:   uint32_t end = std::min(std::min(mRoundedClipRects.Length(), aMax),
michael@0:                           aOther.mRoundedClipRects.Length());
michael@0:   uint32_t clipCount = 0;
michael@0:   for (; clipCount < end; ++clipCount) {
michael@0:     if (mRoundedClipRects[clipCount] !=
michael@0:         aOther.mRoundedClipRects[clipCount]) {
michael@0:       return clipCount;
michael@0:     }
michael@0:   }
michael@0:   return clipCount;
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::AppendRoundedRects(nsTArray<RoundedRect>* aArray, uint32_t aCount) const
michael@0: {
michael@0:   uint32_t count = std::min(mRoundedClipRects.Length(), aCount);
michael@0:   for (uint32_t i = 0; i < count; ++i) {
michael@0:     *aArray->AppendElement() = mRoundedClipRects[i];
michael@0:   }
michael@0: }
michael@0: 
michael@0: bool
michael@0: DisplayItemClip::ComputeRegionInClips(DisplayItemClip* aOldClip,
michael@0:                                       const nsPoint& aShift,
michael@0:                                       nsRegion* aCombined) const
michael@0: {
michael@0:   if (!mHaveClipRect || (aOldClip && !aOldClip->mHaveClipRect)) {
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   if (aOldClip) {
michael@0:     *aCombined = aOldClip->NonRoundedIntersection();
michael@0:     aCombined->MoveBy(aShift);
michael@0:     aCombined->Or(*aCombined, NonRoundedIntersection());
michael@0:   } else {
michael@0:     *aCombined = NonRoundedIntersection();
michael@0:   }
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::MoveBy(nsPoint aPoint)
michael@0: {
michael@0:   if (!mHaveClipRect)
michael@0:     return;
michael@0:   mClipRect += aPoint;
michael@0:   for (uint32_t i = 0; i < mRoundedClipRects.Length(); ++i) {
michael@0:     mRoundedClipRects[i].mRect += aPoint;
michael@0:   }
michael@0: }
michael@0: 
michael@0: static DisplayItemClip* gNoClip;
michael@0: 
michael@0: const DisplayItemClip&
michael@0: DisplayItemClip::NoClip()
michael@0: {
michael@0:   if (!gNoClip) {
michael@0:     gNoClip = new DisplayItemClip();
michael@0:   }
michael@0:   return *gNoClip;
michael@0: }
michael@0: 
michael@0: void
michael@0: DisplayItemClip::Shutdown()
michael@0: {
michael@0:   delete gNoClip;
michael@0:   gNoClip = nullptr;
michael@0: }
michael@0: 
michael@0: #ifdef MOZ_DUMP_PAINTING
michael@0: nsCString
michael@0: DisplayItemClip::ToString() const
michael@0: {
michael@0:   nsAutoCString str;
michael@0:   if (mHaveClipRect) {
michael@0:     str.AppendPrintf("%d,%d,%d,%d", mClipRect.x, mClipRect.y,
michael@0:                      mClipRect.width, mClipRect.height);
michael@0:     for (uint32_t i = 0; i < mRoundedClipRects.Length(); ++i) {
michael@0:       const RoundedRect& r = mRoundedClipRects[i];
michael@0:       str.AppendPrintf(" [%d,%d,%d,%d corners %d,%d,%d,%d,%d,%d,%d,%d]",
michael@0:                        r.mRect.x, r.mRect.y, r.mRect.width, r.mRect.height,
michael@0:                        r.mRadii[0], r.mRadii[1], r.mRadii[2], r.mRadii[3],
michael@0:                        r.mRadii[4], r.mRadii[5], r.mRadii[6], r.mRadii[7]);
michael@0:     }
michael@0:   }
michael@0:   return str;
michael@0: }
michael@0: #endif
michael@0: 
michael@0: }