add new onClip* methods to SkCanvas

src/core/SkCanvas.cpp

 
 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkCanvas.h"
@@ skipping 1148 matching lines @@
 void SkCanvas::resetMatrix() {
     SkMatrix matrix;
 
     matrix.reset();
     this->setMatrix(matrix);
 }
 
 //////////////////////////////////////////////////////////////////////////////
 
 bool SkCanvas::clipRect(const SkRect& rect, SkRegion::Op op, bool doAA) {
+    ClipEdgeStyle edgeStyle = doAA ? kSoft_ClipEdgeStyle : kHard_ClipEdgeStyle;
+    this->onClipRect(rect, op, edgeStyle);
+    return !this->isClipEmpty();
+}
+
+void SkCanvas::onClipRect(const SkRect& rect, SkRegion::Op op, ClipEdgeStyle edgeStyle) {
 #ifdef SK_ENABLE_CLIP_QUICKREJECT
     if (SkRegion::kIntersect_Op == op) {
         if (fMCRec->fRasterClip->isEmpty()) {
             return false;
         }
 
         if (this->quickReject(rect)) {
             fDeviceCMDirty = true;
             fCachedLocalClipBoundsDirty = true;
 
             fClipStack.clipEmpty();
             return fMCRec->fRasterClip->setEmpty();
         }
     }
 #endif
 
     AutoValidateClip avc(this);
 
     fDeviceCMDirty = true;
     fCachedLocalClipBoundsDirty = true;
-    doAA &= fAllowSoftClip;
+    if (!fAllowSoftClip) {
+        edgeStyle = kHard_ClipEdgeStyle;
+    }
 
     if (fMCRec->fMatrix->rectStaysRect()) {
         // for these simpler matrices, we can stay a rect even after applying
         // the matrix. This means we don't have to a) make a path, and b) tell
         // the region code to scan-convert the path, only to discover that it
         // is really just a rect.
         SkRect      r;
 
         fMCRec->fMatrix->mapRect(&r, rect);
-        fClipStack.clipDevRect(r, op, doAA);
-        return fMCRec->fRasterClip->op(r, op, doAA);
+        fClipStack.clipDevRect(r, op, kSoft_ClipEdgeStyle == edgeStyle);
+        fMCRec->fRasterClip->op(r, op, kSoft_ClipEdgeStyle == edgeStyle);
     } else {
         // since we're rotated or some such thing, we convert the rect to a path
         // and clip against that, since it can handle any matrix. However, to
         // avoid recursion in the case where we are subclassed (e.g. Pictures)
         // we explicitly call "our" version of clipPath.
         SkPath  path;
 
         path.addRect(rect);
-        return this->SkCanvas::clipPath(path, op, doAA);
+        this->SkCanvas::onClipPath(path, op, edgeStyle);
     }
 }
 
-static bool clipPathHelper(const SkCanvas* canvas, SkRasterClip* currClip,
-                           const SkPath& devPath, SkRegion::Op op, bool doAA) {
+static void clip_path_helper(const SkCanvas* canvas, SkRasterClip* currClip,
+                             const SkPath& devPath, SkRegion::Op op, bool doAA) {
     // base is used to limit the size (and therefore memory allocation) of the
     // region that results from scan converting devPath.
     SkRegion base;
 
     if (SkRegion::kIntersect_Op == op) {
         // since we are intersect, we can do better (tighter) with currRgn's
         // bounds, than just using the device. However, if currRgn is complex,
         // our region blitter may hork, so we do that case in two steps.
         if (currClip->isRect()) {
             // FIXME: we should also be able to do this when currClip->isBW(),
             // but relaxing the test above triggers GM asserts in
             // SkRgnBuilder::blitH(). We need to investigate what's going on.
-            return currClip->setPath(devPath, currClip->bwRgn(), doAA);
+            currClip->setPath(devPath, currClip->bwRgn(), doAA);
         } else {
             base.setRect(currClip->getBounds());
             SkRasterClip clip;
             clip.setPath(devPath, base, doAA);
-            return currClip->op(clip, op);
+            currClip->op(clip, op);
         }
     } else {
         const SkBaseDevice* device = canvas->getDevice();
         if (!device) {
-            return currClip->setEmpty();
+            currClip->setEmpty();
+            return;
         }
 
         base.setRect(0, 0, device->width(), device->height());
 
         if (SkRegion::kReplace_Op == op) {
-            return currClip->setPath(devPath, base, doAA);
+            currClip->setPath(devPath, base, doAA);
         } else {
             SkRasterClip clip;
             clip.setPath(devPath, base, doAA);
-            return currClip->op(clip, op);
+            currClip->op(clip, op);
         }
     }
 }
 
 bool SkCanvas::clipRRect(const SkRRect& rrect, SkRegion::Op op, bool doAA) {
+    ClipEdgeStyle edgeStyle = doAA ? kSoft_ClipEdgeStyle : kHard_ClipEdgeStyle;
     if (rrect.isRect()) {
-        // call the non-virtual version
-        return this->SkCanvas::clipRect(rrect.getBounds(), op, doAA);
+        this->onClipRect(rrect.getBounds(), op, edgeStyle);
+    } else {
+        this->onClipRRect(rrect, op, edgeStyle);
     }
+    return !this->isClipEmpty();
+}
 
+void SkCanvas::onClipRRect(const SkRRect& rrect, SkRegion::Op op, ClipEdgeStyle edgeStyle) {
     SkRRect transformedRRect;
     if (rrect.transform(*fMCRec->fMatrix, &transformedRRect)) {
         AutoValidateClip avc(this);
 
         fDeviceCMDirty = true;
         fCachedLocalClipBoundsDirty = true;
-        doAA &= fAllowSoftClip;
+        if (!fAllowSoftClip) {
+            edgeStyle = kHard_ClipEdgeStyle;
+        }
 
-        fClipStack.clipDevRRect(transformedRRect, op, doAA);
+        fClipStack.clipDevRRect(transformedRRect, op, kSoft_ClipEdgeStyle == edgeStyle);
 
         SkPath devPath;
         devPath.addRRect(transformedRRect);
 
-        return clipPathHelper(this, fMCRec->fRasterClip, devPath, op, doAA);
+        clip_path_helper(this, fMCRec->fRasterClip, devPath, op, kSoft_ClipEdgeStyle == edgeStyle);
+        return;
     }
 
     SkPath path;
     path.addRRect(rrect);
     // call the non-virtual version
-    return this->SkCanvas::clipPath(path, op, doAA);
+    this->SkCanvas::onClipPath(path, op, edgeStyle);
 }
 
 bool SkCanvas::clipPath(const SkPath& path, SkRegion::Op op, bool doAA) {
+    ClipEdgeStyle edgeStyle = doAA ? kSoft_ClipEdgeStyle : kHard_ClipEdgeStyle;
+    SkRect r;
+    if (!path.isInverseFillType() && path.isRect(&r)) {
+        this->onClipRect(r, op, edgeStyle);
+    } else {
+        this->onClipPath(path, op, edgeStyle);
+    }
+
+    return !this->isClipEmpty();
+}
+
+void SkCanvas::onClipPath(const SkPath& path, SkRegion::Op op, ClipEdgeStyle edgeStyle) {
 #ifdef SK_ENABLE_CLIP_QUICKREJECT
     if (SkRegion::kIntersect_Op == op && !path.isInverseFillType()) {
         if (fMCRec->fRasterClip->isEmpty()) {
             return false;
         }
 
         if (this->quickReject(path.getBounds())) {
             fDeviceCMDirty = true;
             fCachedLocalClipBoundsDirty = true;
 
             fClipStack.clipEmpty();
             return fMCRec->fRasterClip->setEmpty();
         }
     }
 #endif
 
     AutoValidateClip avc(this);
 
     fDeviceCMDirty = true;
     fCachedLocalClipBoundsDirty = true;
-    doAA &= fAllowSoftClip;
+    if (!fAllowSoftClip) {
+        edgeStyle = kHard_ClipEdgeStyle;
+    }
 
     SkPath devPath;
     path.transform(*fMCRec->fMatrix, &devPath);
 
     // Check if the transfomation, or the original path itself
     // made us empty. Note this can also happen if we contained NaN
     // values. computing the bounds detects this, and will set our
     // bounds to empty if that is the case. (see SkRect::set(pts, count))
     if (devPath.getBounds().isEmpty()) {
         // resetting the path will remove any NaN or other wanky values
         // that might upset our scan converter.
         devPath.reset();
     }
 
     // if we called path.swap() we could avoid a deep copy of this path
-    fClipStack.clipDevPath(devPath, op, doAA);
+    fClipStack.clipDevPath(devPath, op, kSoft_ClipEdgeStyle == edgeStyle);
 
     if (fAllowSimplifyClip) {
         devPath.reset();
         devPath.setFillType(SkPath::kInverseEvenOdd_FillType);
         const SkClipStack* clipStack = getClipStack();
         SkClipStack::Iter iter(*clipStack, SkClipStack::Iter::kBottom_IterStart);
         const SkClipStack::Element* element;
         while ((element = iter.next())) {
             SkClipStack::Element::Type type = element->getType();
             if (type == SkClipStack::Element::kEmpty_Type) {
                 continue;
             }
             SkPath operand;
             element->asPath(&operand);
             SkRegion::Op elementOp = element->getOp();
             if (elementOp == SkRegion::kReplace_Op) {
                 devPath = operand;
             } else {
                 Op(devPath, operand, (SkPathOp) elementOp, &devPath);
             }
             // if the prev and curr clips disagree about aa -vs- not, favor the aa request.
             // perhaps we need an API change to avoid this sort of mixed-signals about
             // clipping.
-            doAA |= element->isAA();
+            if (element->isAA()) {
+                edgeStyle = kSoft_ClipEdgeStyle;
+            }
         }
         op = SkRegion::kReplace_Op;
     }
 
-    return clipPathHelper(this, fMCRec->fRasterClip, devPath, op, doAA);
+    clip_path_helper(this, fMCRec->fRasterClip, devPath, op, edgeStyle);
 }
 
 bool SkCanvas::updateClipConservativelyUsingBounds(const SkRect& bounds, SkRegion::Op op,
                                                    bool inverseFilled) {
     // This is for updating the clip conservatively using only bounds
     // information.
     // Contract:
     //    The current clip must contain the true clip. The true
     //    clip is the clip that would have normally been computed
     //    by calls to clipPath and clipRRect
     // Objective:
     //    Keep the current clip as small as possible without
     //    breaking the contract, using only clip bounding rectangles
     //    (for performance).
 
     // N.B.: This *never* calls back through a virtual on canvas, so subclasses
     // don't have to worry about getting caught in a loop. Thus anywhere
     // we call a virtual method, we explicitly prefix it with
     // SkCanvas:: to be sure to call the base-class.
 
     if (inverseFilled) {
         switch (op) {
             case SkRegion::kIntersect_Op:
             case SkRegion::kDifference_Op:
                 // These ops can only shrink the current clip. So leaving
-                // the clip unchanges conservatively respects the contract.
-                return this->getClipDeviceBounds(NULL);
+                // the clip unchanged conservatively respects the contract.
+                break;
             case SkRegion::kUnion_Op:
             case SkRegion::kReplace_Op:
             case SkRegion::kReverseDifference_Op:
-            case SkRegion::kXOR_Op:
-                {
+            case SkRegion::kXOR_Op: {
                     // These ops can grow the current clip up to the extents of
                     // the input clip, which is inverse filled, so we just set
                     // the current clip to the device bounds.
                     SkRect deviceBounds;
                     SkIRect deviceIBounds;
                     this->getDevice()->getGlobalBounds(&deviceIBounds);
                     deviceBounds = SkRect::Make(deviceIBounds);
                     this->SkCanvas::save(SkCanvas::kMatrix_SaveFlag);
                     // set the clip in device space
                     this->SkCanvas::setMatrix(SkMatrix::I());
-                    bool result = this->SkCanvas::clipRect(deviceBounds,
-                        SkRegion::kReplace_Op, false);
+                    this->SkCanvas::onClipRect(deviceBounds, SkRegion::kReplace_Op, 
+                                               kHard_ClipEdgeStyle);
                     this->SkCanvas::restore(); //pop the matrix, but keep the clip
-                    return result;
-                }
+                    break;
+            }
             default:
                 SkASSERT(0); // unhandled op?
         }
     } else {
         // Not inverse filled
         switch (op) {
             case SkRegion::kIntersect_Op:
             case SkRegion::kUnion_Op:
             case SkRegion::kReplace_Op:
-                return this->SkCanvas::clipRect(bounds, op, false);
+                this->SkCanvas::onClipRect(bounds, op, kHard_ClipEdgeStyle);
+                break;
             case SkRegion::kDifference_Op:
                 // Difference can only shrink the current clip.
                 // Leaving clip unchanged conservatively fullfills the contract.
-                return this->getClipDeviceBounds(NULL);
+                break;
             case SkRegion::kReverseDifference_Op:
                 // To reverse, we swap in the bounds with a replace op.
                 // As with difference, leave it unchanged.
-                return this->SkCanvas::clipRect(bounds, SkRegion::kReplace_Op, false);
+                this->SkCanvas::onClipRect(bounds, SkRegion::kReplace_Op, kHard_ClipEdgeStyle);
+                break;
             case SkRegion::kXOR_Op:
                 // Be conservative, based on (A XOR B) always included in (A union B),
                 // which is always included in (bounds(A) union bounds(B))
-                return this->SkCanvas::clipRect(bounds, SkRegion::kUnion_Op, false);
+                this->SkCanvas::onClipRect(bounds, SkRegion::kUnion_Op, kHard_ClipEdgeStyle);
+                break;
             default:
                 SkASSERT(0); // unhandled op?
         }
     }
-    return true;
+
+    return !this->isClipEmpty();
 }
 
 bool SkCanvas::clipRegion(const SkRegion& rgn, SkRegion::Op op) {
+    this->onClipRegion(rgn, op);
+    return !this->isClipEmpty();
+}
+
+void SkCanvas::onClipRegion(const SkRegion& rgn, SkRegion::Op op) {
     AutoValidateClip avc(this);
 
     fDeviceCMDirty = true;
     fCachedLocalClipBoundsDirty = true;
 
     // todo: signal fClipStack that we have a region, and therefore (I guess)
     // we have to ignore it, and use the region directly?
     fClipStack.clipDevRect(rgn.getBounds(), op);
 
-    return fMCRec->fRasterClip->op(rgn, op);
+    fMCRec->fRasterClip->op(rgn, op);
 }
 
 #ifdef SK_DEBUG
 void SkCanvas::validateClip() const {
     // construct clipRgn from the clipstack
     const SkBaseDevice* device = this->getDevice();
     if (!device) {
         SkASSERT(this->getTotalClip().isEmpty());
         return;
     }
 
     SkIRect ir;
     ir.set(0, 0, device->width(), device->height());
     SkRasterClip tmpClip(ir);
 
     SkClipStack::B2TIter                iter(fClipStack);
     const SkClipStack::Element* element;
     while ((element = iter.next()) != NULL) {
         switch (element->getType()) {
             case SkClipStack::Element::kRect_Type:
                 element->getRect().round(&ir);
                 tmpClip.op(ir, element->getOp());
                 break;
             case SkClipStack::Element::kEmpty_Type:
                 tmpClip.setEmpty();
                 break;
             default: {
                 SkPath path;
                 element->asPath(&path);
-                clipPathHelper(this,
-                               &tmpClip,
-                               path,
-                               element->getOp(),
-                               element->isAA());
+                clip_path_helper(this, &tmpClip, path, element->getOp(), element->isAA());
                 break;
             }
         }
     }
 
 #if 0   // enable this locally for testing
     // now compare against the current rgn
     const SkRegion& rgn = this->getTotalClip();
     SkASSERT(rgn == tmpClip);
 #endif
@@ skipping 58 matching lines @@
         return false;
     }
 }
 
 bool SkCanvas::quickReject(const SkPath& path) const {
     return path.isEmpty() || this->quickReject(path.getBounds());
 }
 
 bool SkCanvas::getClipBounds(SkRect* bounds) const {
     SkIRect ibounds;
-    if (!getClipDeviceBounds(&ibounds)) {
+    if (!this->getClipDeviceBounds(&ibounds)) {
         return false;
     }
 
     SkMatrix inverse;
     // if we can't invert the CTM, we can't return local clip bounds
     if (!fMCRec->fMatrix->invert(&inverse)) {
         if (bounds) {
             bounds->setEmpty();
         }
         return false;
@@ skipping 24 matching lines @@
         *bounds = clip.getBounds();
     }
     return true;
 }
 
 const SkMatrix& SkCanvas::getTotalMatrix() const {
     return *fMCRec->fMatrix;
 }
 
 SkCanvas::ClipType SkCanvas::getClipType() const {
-    if (fMCRec->fRasterClip->isEmpty()) return kEmpty_ClipType;
-    if (fMCRec->fRasterClip->isRect()) return kRect_ClipType;
+    if (fMCRec->fRasterClip->isEmpty()) {
+        return kEmpty_ClipType;
+    }
+    if (fMCRec->fRasterClip->isRect()) {
+        return kRect_ClipType;
+    }
     return kComplex_ClipType;
 }
 
 const SkRegion& SkCanvas::getTotalClip() const {
     return fMCRec->fRasterClip->forceGetBW();
 }
 
 SkBaseDevice* SkCanvas::createLayerDevice(const SkImageInfo& info) {
     SkBaseDevice* device = this->getTopDevice();
     return device ? device->createCompatibleDeviceForSaveLayer(info) : NULL;
@@ skipping 744 matching lines @@
     if (!bitmap.allocPixels(info)) {
         return NULL;
     }
 
     // should this functionality be moved into allocPixels()?
     if (!bitmap.info().isOpaque()) {
         bitmap.eraseColor(0);
     }
     return SkNEW_ARGS(SkCanvas, (bitmap));
 }