1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/pathops/SkPathWriter.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,166 @@
1.4 +/*
1.5 + * Copyright 2012 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +#include "SkPathOpsPoint.h"
1.11 +#include "SkPathWriter.h"
1.12 +
1.13 +// wrap path to keep track of whether the contour is initialized and non-empty
1.14 +SkPathWriter::SkPathWriter(SkPath& path)
1.15 + : fPathPtr(&path)
1.16 + , fCloses(0)
1.17 + , fMoves(0)
1.18 +{
1.19 + init();
1.20 +}
1.21 +
1.22 +void SkPathWriter::close() {
1.23 + if (!fHasMove) {
1.24 + return;
1.25 + }
1.26 + bool callClose = isClosed();
1.27 + lineTo();
1.28 + if (fEmpty) {
1.29 + return;
1.30 + }
1.31 + if (callClose) {
1.32 +#if DEBUG_PATH_CONSTRUCTION
1.33 + SkDebugf("path.close();\n");
1.34 +#endif
1.35 + fPathPtr->close();
1.36 + fCloses++;
1.37 + }
1.38 + init();
1.39 +}
1.40 +
1.41 +void SkPathWriter::cubicTo(const SkPoint& pt1, const SkPoint& pt2, const SkPoint& pt3) {
1.42 + lineTo();
1.43 + if (fEmpty && AlmostEqualUlps(fDefer[0], pt1) && AlmostEqualUlps(pt1, pt2)
1.44 + && AlmostEqualUlps(pt2, pt3)) {
1.45 + deferredLine(pt3);
1.46 + return;
1.47 + }
1.48 + moveTo();
1.49 + fDefer[1] = pt3;
1.50 + nudge();
1.51 + fDefer[0] = fDefer[1];
1.52 +#if DEBUG_PATH_CONSTRUCTION
1.53 + SkDebugf("path.cubicTo(%1.9g,%1.9g, %1.9g,%1.9g, %1.9g,%1.9g);\n",
1.54 + pt1.fX, pt1.fY, pt2.fX, pt2.fY, fDefer[1].fX, fDefer[1].fY);
1.55 +#endif
1.56 + fPathPtr->cubicTo(pt1.fX, pt1.fY, pt2.fX, pt2.fY, fDefer[1].fX, fDefer[1].fY);
1.57 + fEmpty = false;
1.58 +}
1.59 +
1.60 +void SkPathWriter::deferredLine(const SkPoint& pt) {
1.61 + if (pt == fDefer[1]) {
1.62 + return;
1.63 + }
1.64 + if (changedSlopes(pt)) {
1.65 + lineTo();
1.66 + fDefer[0] = fDefer[1];
1.67 + }
1.68 + fDefer[1] = pt;
1.69 +}
1.70 +
1.71 +void SkPathWriter::deferredMove(const SkPoint& pt) {
1.72 + fMoved = true;
1.73 + fHasMove = true;
1.74 + fEmpty = true;
1.75 + fDefer[0] = fDefer[1] = pt;
1.76 +}
1.77 +
1.78 +void SkPathWriter::deferredMoveLine(const SkPoint& pt) {
1.79 + if (!fHasMove) {
1.80 + deferredMove(pt);
1.81 + }
1.82 + deferredLine(pt);
1.83 +}
1.84 +
1.85 +bool SkPathWriter::hasMove() const {
1.86 + return fHasMove;
1.87 +}
1.88 +
1.89 +void SkPathWriter::init() {
1.90 + fEmpty = true;
1.91 + fHasMove = false;
1.92 + fMoved = false;
1.93 +}
1.94 +
1.95 +bool SkPathWriter::isClosed() const {
1.96 + return !fEmpty && SkDPoint::ApproximatelyEqual(fFirstPt, fDefer[1]);
1.97 +}
1.98 +
1.99 +void SkPathWriter::lineTo() {
1.100 + if (fDefer[0] == fDefer[1]) {
1.101 + return;
1.102 + }
1.103 + moveTo();
1.104 + nudge();
1.105 + fEmpty = false;
1.106 +#if DEBUG_PATH_CONSTRUCTION
1.107 + SkDebugf("path.lineTo(%1.9g,%1.9g);\n", fDefer[1].fX, fDefer[1].fY);
1.108 +#endif
1.109 + fPathPtr->lineTo(fDefer[1].fX, fDefer[1].fY);
1.110 + fDefer[0] = fDefer[1];
1.111 +}
1.112 +
1.113 +const SkPath* SkPathWriter::nativePath() const {
1.114 + return fPathPtr;
1.115 +}
1.116 +
1.117 +void SkPathWriter::nudge() {
1.118 + if (fEmpty || !AlmostEqualUlps(fDefer[1].fX, fFirstPt.fX)
1.119 + || !AlmostEqualUlps(fDefer[1].fY, fFirstPt.fY)) {
1.120 + return;
1.121 + }
1.122 + fDefer[1] = fFirstPt;
1.123 +}
1.124 +
1.125 +void SkPathWriter::quadTo(const SkPoint& pt1, const SkPoint& pt2) {
1.126 + lineTo();
1.127 + if (fEmpty && AlmostEqualUlps(fDefer[0], pt1) && AlmostEqualUlps(pt1, pt2)) {
1.128 + deferredLine(pt2);
1.129 + return;
1.130 + }
1.131 + moveTo();
1.132 + fDefer[1] = pt2;
1.133 + nudge();
1.134 + fDefer[0] = fDefer[1];
1.135 +#if DEBUG_PATH_CONSTRUCTION
1.136 + SkDebugf("path.quadTo(%1.9g,%1.9g, %1.9g,%1.9g);\n",
1.137 + pt1.fX, pt1.fY, fDefer[1].fX, fDefer[1].fY);
1.138 +#endif
1.139 + fPathPtr->quadTo(pt1.fX, pt1.fY, fDefer[1].fX, fDefer[1].fY);
1.140 + fEmpty = false;
1.141 +}
1.142 +
1.143 +bool SkPathWriter::someAssemblyRequired() const {
1.144 + return fCloses < fMoves;
1.145 +}
1.146 +
1.147 +bool SkPathWriter::changedSlopes(const SkPoint& pt) const {
1.148 + if (fDefer[0] == fDefer[1]) {
1.149 + return false;
1.150 + }
1.151 + SkScalar deferDx = fDefer[1].fX - fDefer[0].fX;
1.152 + SkScalar deferDy = fDefer[1].fY - fDefer[0].fY;
1.153 + SkScalar lineDx = pt.fX - fDefer[1].fX;
1.154 + SkScalar lineDy = pt.fY - fDefer[1].fY;
1.155 + return deferDx * lineDy != deferDy * lineDx;
1.156 +}
1.157 +
1.158 +void SkPathWriter::moveTo() {
1.159 + if (!fMoved) {
1.160 + return;
1.161 + }
1.162 + fFirstPt = fDefer[0];
1.163 +#if DEBUG_PATH_CONSTRUCTION
1.164 + SkDebugf("path.moveTo(%1.9g,%1.9g);\n", fDefer[0].fX, fDefer[0].fY);
1.165 +#endif
1.166 + fPathPtr->moveTo(fDefer[0].fX, fDefer[0].fY);
1.167 + fMoved = false;
1.168 + fMoves++;
1.169 +}
