Chop quads exactly on the clip bounds, so we don't spend CPU cycles walking them
when we're above or below the clip. Still to do: - chop in X to avoid 16.16. overflow in the edgelist - apply the same logic for cubics (tho much harder math) git-svn-id: http://skia.googlecode.com/svn/trunk@88 2bbb7eff-a529-9590-31e7-b0007b416f81
This commit is contained in:
reed@android.com
parent
3a859a0034
commit
c07d23a6e2
85
samplecode/SamplePathClip.cpp
Normal file
85
samplecode/SamplePathClip.cpp
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@ -0,0 +1,85 @@
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#include "SampleCode.h"
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#include "SkView.h"
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#include "SkCanvas.h"
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#include "SkGradientShader.h"
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#include "SkGraphics.h"
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#include "SkImageDecoder.h"
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#include "SkPath.h"
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#include "SkPorterDuff.h"
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#include "SkRegion.h"
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#include "SkShader.h"
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#include "SkUtils.h"
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#include "SkXfermode.h"
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#include "SkColorPriv.h"
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#include "SkColorFilter.h"
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#include "SkTime.h"
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#include "SkTypeface.h"
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class PathClipView : public SkView {
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public:
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SkRect fOval;
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SkPoint fCenter;
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PathClipView() {
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fOval.set(0, 0, SkIntToScalar(200), SkIntToScalar(50));
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fCenter.set(SkIntToScalar(250), SkIntToScalar(250));
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}
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virtual ~PathClipView() {}
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protected:
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// overrides from SkEventSink
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virtual bool onQuery(SkEvent* evt) {
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if (SampleCode::TitleQ(*evt)) {
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SampleCode::TitleR(evt, "PathClip");
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return true;
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}
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return this->INHERITED::onQuery(evt);
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}
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void drawBG(SkCanvas* canvas) {
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canvas->drawColor(SK_ColorWHITE);
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}
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virtual void onDraw(SkCanvas* canvas) {
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this->drawBG(canvas);
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SkRect oval = fOval;
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oval.offset(fCenter.fX - oval.centerX(), fCenter.fY - oval.centerY());
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SkPaint p;
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p.setAntiAlias(true);
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p.setStyle(SkPaint::kStroke_Style);
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canvas->drawOval(oval, p);
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SkRect r;
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r.set(SkIntToScalar(200), SkIntToScalar(200),
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SkIntToScalar(300), SkIntToScalar(300));
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canvas->clipRect(r);
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p.setStyle(SkPaint::kFill_Style);
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p.setColor(SK_ColorRED);
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canvas->drawRect(r, p);
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p.setColor(0x800000FF);
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r.set(SkIntToScalar(150), SkIntToScalar(10),
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SkIntToScalar(250), SkIntToScalar(400));
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canvas->drawOval(oval, p);
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}
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virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y) {
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fCenter.set(x, y);
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this->inval(NULL);
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return NULL;
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}
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private:
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typedef SkView INHERITED;
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};
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//////////////////////////////////////////////////////////////////////////////
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static SkView* MyFactory() { return new PathClipView; }
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static SkViewRegister reg(MyFactory);
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@ -173,7 +173,7 @@ static inline int diff_to_shift(SkFDot6 dx, SkFDot6 dy)
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return (32 - SkCLZ(dist)) >> 1;
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}
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int SkQuadraticEdge::setQuadratic(const SkPoint pts[3], const SkIRect* clip, int shift)
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int SkQuadraticEdge::setQuadratic(const SkPoint pts[3], int shift)
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{
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SkFDot6 x0, y0, x1, y1, x2, y2;
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@ -212,9 +212,6 @@ int SkQuadraticEdge::setQuadratic(const SkPoint pts[3], const SkIRect* clip, int
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// are we a zero-height quad (line)?
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if (top == bot)
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return 0;
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// are we completely above or below the clip?
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if (clip && (top >= clip->fBottom || bot <= clip->fTop))
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return 0;
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// compute number of steps needed (1 << shift)
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{
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@ -252,15 +249,6 @@ int SkQuadraticEdge::setQuadratic(const SkPoint pts[3], const SkIRect* clip, int
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fQLastX = SkFDot6ToFixed(x2);
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fQLastY = SkFDot6ToFixed(y2);
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if (clip)
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{
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do {
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for (;!this->updateQuadratic();)
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;
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} while (!this->intersectsClip(*clip));
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this->chopLineWithClip(*clip);
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return 1;
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}
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return this->updateQuadratic();
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}
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@ -75,7 +75,7 @@ struct SkQuadraticEdge : public SkEdge {
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SkFixed fQDDx, fQDDy;
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SkFixed fQLastX, fQLastY;
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int setQuadratic(const SkPoint pts[3], const SkIRect* clip, int shiftUp);
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int setQuadratic(const SkPoint pts[3], int shiftUp);
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int updateQuadratic();
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};
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92
src/core/SkQuadClipper.cpp
Normal file
92
src/core/SkQuadClipper.cpp
Normal file
@ -0,0 +1,92 @@
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/*
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* Copyright (C) 2009 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include "SkQuadClipper.h"
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#include "SkGeometry.h"
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static bool chopMonoQuadAtY(SkPoint pts[3], SkScalar y, SkScalar* t) {
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/* Solve F(t) = y where F(t) := [0](1-t)^2 + 2[1]t(1-t) + [2]t^2
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* We solve for t, using quadratic equation, hence we have to rearrange
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* our cooefficents to look like At^2 + Bt + C
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*/
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SkScalar A = pts[0].fY - pts[1].fY - pts[1].fY + pts[2].fY;
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SkScalar B = 2*(pts[1].fY - pts[0].fY);
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SkScalar C = pts[0].fY - y;
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SkScalar roots[2]; // we only expect one, but make room for 2 for safety
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int count = SkFindUnitQuadRoots(A, B, C, roots);
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if (count) {
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*t = roots[0];
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return true;
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}
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return false;
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}
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SkQuadClipper::SkQuadClipper() {}
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void SkQuadClipper::setClip(const SkIRect& clip) {
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// conver to scalars, since that's where we'll see the points
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fClip.set(clip);
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}
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/* If we somehow returned the fact that we had to flip the pts in Y, we could
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communicate that to setQuadratic, and then avoid having to flip it back
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here (only to have setQuadratic do the flip again)
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*/
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bool SkQuadClipper::clipQuad(const SkPoint srcPts[3], SkPoint dst[3]) {
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bool reverse;
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// we need the data to be monotonically descending in Y
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if (srcPts[0].fY > srcPts[2].fY) {
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dst[0] = srcPts[2];
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dst[1] = srcPts[1];
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dst[2] = srcPts[0];
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reverse = true;
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} else {
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memcpy(dst, srcPts, 3 * sizeof(SkPoint));
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reverse = false;
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}
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// are we completely above or below
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const SkScalar ctop = fClip.fTop;
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const SkScalar cbot = fClip.fBottom;
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if (dst[2].fY <= ctop || dst[0].fY >= cbot) {
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return false;
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}
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SkScalar t;
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SkPoint tmp[5]; // for SkChopQuadAt
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// are we partially above
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if (dst[0].fY < ctop && chopMonoQuadAtY(dst, ctop, &t)) {
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SkChopQuadAt(dst, tmp, t);
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dst[0] = tmp[2];
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dst[1] = tmp[3];
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}
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// are we partially below
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if (dst[2].fY > cbot && chopMonoQuadAtY(dst, cbot, &t)) {
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SkChopQuadAt(dst, tmp, t);
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dst[1] = tmp[1];
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dst[2] = tmp[2];
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}
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if (reverse) {
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SkTSwap<SkPoint>(dst[0], dst[2]);
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}
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return true;
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}
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41
src/core/SkQuadClipper.h
Normal file
41
src/core/SkQuadClipper.h
Normal file
@ -0,0 +1,41 @@
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/*
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* Copyright (C) 2009 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef SkQuadClipper_DEFINED
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#define SkQuadClipper_DEFINED
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#include "SkPoint.h"
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#include "SkRect.h"
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/** This class is initialized with a clip rectangle, and then can be fed quads,
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which must already be monotonic in Y.
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In the future, it might return a series of segments, allowing it to clip
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also in X, to ensure that all segments fit in a finite coordinate system.
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*/
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class SkQuadClipper {
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public:
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SkQuadClipper();
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void setClip(const SkIRect& clip);
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bool clipQuad(const SkPoint src[3], SkPoint dst[3]);
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private:
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SkRect fClip;
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};
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#endif
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@ -20,6 +20,7 @@
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#include "SkEdge.h"
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#include "SkGeometry.h"
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#include "SkPath.h"
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#include "SkQuadClipper.h"
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#include "SkRegion.h"
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#include "SkTemplates.h"
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@ -306,6 +307,14 @@ static int build_edges(SkEdge edge[], const SkPath& path,
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SkPath::Iter iter(path, true);
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SkPoint pts[4];
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SkPath::Verb verb;
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SkQuadClipper qclipper;
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if (clipRect) {
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SkIRect r;
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r.set(clipRect->fLeft >> shiftUp, clipRect->fTop >> shiftUp,
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clipRect->fRight >> shiftUp, clipRect->fBottom >> shiftUp);
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qclipper.setClip(r);
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}
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while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
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switch (verb) {
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@ -316,17 +325,23 @@ static int build_edges(SkEdge edge[], const SkPath& path,
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}
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break;
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case SkPath::kQuad_Verb: {
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SkPoint tmp[5];
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SkPoint tmp[5], clippedPts[3];
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SkPoint* p = tmp;
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int count = SkChopQuadAtYExtrema(pts, tmp);
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do {
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if (((SkQuadraticEdge*)edge)->setQuadratic(p, clipRect,
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shiftUp))
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{
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const SkPoint* qpts = p;
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if (clipRect) {
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if (!qclipper.clipQuad(p, clippedPts)) {
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goto NEXT_CHOPPED_QUAD;
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}
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qpts = clippedPts;
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}
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if (((SkQuadraticEdge*)edge)->setQuadratic(qpts, shiftUp)) {
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*list++ = edge;
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edge = (SkEdge*)((char*)edge + sizeof(SkQuadraticEdge));
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}
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NEXT_CHOPPED_QUAD:
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p += 2;
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} while (--count >= 0);
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break;
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@ -58,6 +58,7 @@ SOURCE := \
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SkPixelRef.cpp \
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SkPoint.cpp \
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SkPtrRecorder.cpp \
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SkQuadClipper.cpp \
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SkRasterizer.cpp \
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SkRect.cpp \
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SkRefCnt.cpp \
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@ -125,6 +125,7 @@
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||||
005F25E60EF94F7900582A90 /* SkWriter32.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 005F256D0EF94F7900582A90 /* SkWriter32.cpp */; };
|
||||
005F25E70EF94F7900582A90 /* SkXfermode.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 005F256E0EF94F7900582A90 /* SkXfermode.cpp */; };
|
||||
005F26960EF955D400582A90 /* SkComposeShader.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 005F26950EF955D400582A90 /* SkComposeShader.cpp */; };
|
||||
007C786A0F3B4D5F0004B142 /* SkQuadClipper.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 007C78690F3B4D5F0004B142 /* SkQuadClipper.cpp */; };
|
||||
/* End PBXBuildFile section */
|
||||
|
||||
/* Begin PBXFileReference section */
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||||
@ -246,6 +247,7 @@
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||||
005F256D0EF94F7900582A90 /* SkWriter32.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SkWriter32.cpp; path = ../../src/core/SkWriter32.cpp; sourceTree = SOURCE_ROOT; };
|
||||
005F256E0EF94F7900582A90 /* SkXfermode.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SkXfermode.cpp; path = ../../src/core/SkXfermode.cpp; sourceTree = SOURCE_ROOT; };
|
||||
005F26950EF955D400582A90 /* SkComposeShader.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SkComposeShader.cpp; path = ../../src/core/SkComposeShader.cpp; sourceTree = SOURCE_ROOT; };
|
||||
007C78690F3B4D5F0004B142 /* SkQuadClipper.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SkQuadClipper.cpp; path = ../../src/core/SkQuadClipper.cpp; sourceTree = SOURCE_ROOT; };
|
||||
D2AAC046055464E500DB518D /* libcore.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libcore.a; sourceTree = BUILT_PRODUCTS_DIR; };
|
||||
/* End PBXFileReference section */
|
||||
|
||||
@ -273,6 +275,7 @@
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||||
08FB7795FE84155DC02AAC07 /* src */ = {
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||||
isa = PBXGroup;
|
||||
children = (
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||||
007C78690F3B4D5F0004B142 /* SkQuadClipper.cpp */,
|
||||
002884D40EFAB8F80083E387 /* SkStream.cpp */,
|
||||
002884C70EFAB8B90083E387 /* SkMMapStream.cpp */,
|
||||
005F26950EF955D400582A90 /* SkComposeShader.cpp */,
|
||||
@ -580,6 +583,7 @@
|
||||
005F26960EF955D400582A90 /* SkComposeShader.cpp in Sources */,
|
||||
002884C80EFAB8B90083E387 /* SkMMapStream.cpp in Sources */,
|
||||
002884D50EFAB8F80083E387 /* SkStream.cpp in Sources */,
|
||||
007C786A0F3B4D5F0004B142 /* SkQuadClipper.cpp in Sources */,
|
||||
);
|
||||
runOnlyForDeploymentPostprocessing = 0;
|
||||
};
|
||||
|
||||
@ -64,6 +64,7 @@
|
||||
007A7CBF0F01658C00A2D6EE /* SampleTypeface.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 007A7CB00F01658C00A2D6EE /* SampleTypeface.cpp */; };
|
||||
007A7CC00F01658C00A2D6EE /* SampleVertices.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 007A7CB10F01658C00A2D6EE /* SampleVertices.cpp */; };
|
||||
007A7CC10F01658C00A2D6EE /* SampleXfermodes.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 007A7CB20F01658C00A2D6EE /* SampleXfermodes.cpp */; };
|
||||
007C785E0F3B4C230004B142 /* SamplePathClip.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 007C785D0F3B4C230004B142 /* SamplePathClip.cpp */; };
|
||||
00A41E4B0EFC312F00C9CBEB /* SampleArc.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 00A41E4A0EFC312F00C9CBEB /* SampleArc.cpp */; };
|
||||
0156F80407C56A3000C6122B /* Foundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 0156F80307C56A3000C6122B /* Foundation.framework */; };
|
||||
01FC44D507BD3BB800D228F4 /* Quartz.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 01FC44D407BD3BB800D228F4 /* Quartz.framework */; };
|
||||
@ -176,6 +177,7 @@
|
||||
007A7CB00F01658C00A2D6EE /* SampleTypeface.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SampleTypeface.cpp; path = ../../samplecode/SampleTypeface.cpp; sourceTree = SOURCE_ROOT; };
|
||||
007A7CB10F01658C00A2D6EE /* SampleVertices.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SampleVertices.cpp; path = ../../samplecode/SampleVertices.cpp; sourceTree = SOURCE_ROOT; };
|
||||
007A7CB20F01658C00A2D6EE /* SampleXfermodes.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SampleXfermodes.cpp; path = ../../samplecode/SampleXfermodes.cpp; sourceTree = SOURCE_ROOT; };
|
||||
007C785D0F3B4C230004B142 /* SamplePathClip.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SamplePathClip.cpp; path = ../../samplecode/SamplePathClip.cpp; sourceTree = SOURCE_ROOT; };
|
||||
00A41E4A0EFC312F00C9CBEB /* SampleArc.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = SampleArc.cpp; path = ../../samplecode/SampleArc.cpp; sourceTree = SOURCE_ROOT; };
|
||||
0156F80307C56A3000C6122B /* Foundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Foundation.framework; path = /System/Library/Frameworks/Foundation.framework; sourceTree = "<absolute>"; };
|
||||
01FC44D407BD3BB800D228F4 /* Quartz.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Quartz.framework; path = /System/Library/Frameworks/Quartz.framework; sourceTree = "<absolute>"; };
|
||||
@ -246,6 +248,7 @@
|
||||
00A41E4A0EFC312F00C9CBEB /* SampleArc.cpp */,
|
||||
00003C620EFC22A8000FF73A /* SampleApp.cpp */,
|
||||
00003C640EFC22A8000FF73A /* SamplePath.cpp */,
|
||||
007C785D0F3B4C230004B142 /* SamplePathClip.cpp */,
|
||||
00003C650EFC22A8000FF73A /* SamplePathEffects.cpp */,
|
||||
);
|
||||
name = samples;
|
||||
@ -505,6 +508,7 @@
|
||||
007A7CC10F01658C00A2D6EE /* SampleXfermodes.cpp in Sources */,
|
||||
0041CE3C0F00A12400695E8C /* SampleEncode.cpp in Sources */,
|
||||
007A7CB60F01658C00A2D6EE /* SampleRegion.cpp in Sources */,
|
||||
007C785E0F3B4C230004B142 /* SamplePathClip.cpp in Sources */,
|
||||
);
|
||||
runOnlyForDeploymentPostprocessing = 0;
|
||||
};
|
||||
|
||||
Loading…
Reference in New Issue
Block a user