|  | /* | 
|  | * Copyright 2012 Google Inc. | 
|  | * | 
|  | * Use of this source code is governed by a BSD-style license that can be | 
|  | * found in the LICENSE file. | 
|  | */ | 
|  | #include "PathOpsTestCommon.h" | 
|  | #include "SkPathOpsBounds.h" | 
|  | #include "SkPathOpsConic.h" | 
|  | #include "SkPathOpsCubic.h" | 
|  | #include "SkPathOpsLine.h" | 
|  | #include "SkPathOpsQuad.h" | 
|  | #include "SkReduceOrder.h" | 
|  | #include "SkTSort.h" | 
|  |  | 
|  | static double calc_t_div(const SkDCubic& cubic, double precision, double start) { | 
|  | const double adjust = sqrt(3.) / 36; | 
|  | SkDCubic sub; | 
|  | const SkDCubic* cPtr; | 
|  | if (start == 0) { | 
|  | cPtr = &cubic; | 
|  | } else { | 
|  | // OPTIMIZE: special-case half-split ? | 
|  | sub = cubic.subDivide(start, 1); | 
|  | cPtr = ⊂ | 
|  | } | 
|  | const SkDCubic& c = *cPtr; | 
|  | double dx = c[3].fX - 3 * (c[2].fX - c[1].fX) - c[0].fX; | 
|  | double dy = c[3].fY - 3 * (c[2].fY - c[1].fY) - c[0].fY; | 
|  | double dist = sqrt(dx * dx + dy * dy); | 
|  | double tDiv3 = precision / (adjust * dist); | 
|  | double t = SkDCubeRoot(tDiv3); | 
|  | if (start > 0) { | 
|  | t = start + (1 - start) * t; | 
|  | } | 
|  | return t; | 
|  | } | 
|  |  | 
|  | static bool add_simple_ts(const SkDCubic& cubic, double precision, SkTArray<double, true>* ts) { | 
|  | double tDiv = calc_t_div(cubic, precision, 0); | 
|  | if (tDiv >= 1) { | 
|  | return true; | 
|  | } | 
|  | if (tDiv >= 0.5) { | 
|  | ts->push_back(0.5); | 
|  | return true; | 
|  | } | 
|  | return false; | 
|  | } | 
|  |  | 
|  | static void addTs(const SkDCubic& cubic, double precision, double start, double end, | 
|  | SkTArray<double, true>* ts) { | 
|  | double tDiv = calc_t_div(cubic, precision, 0); | 
|  | double parts = ceil(1.0 / tDiv); | 
|  | for (double index = 0; index < parts; ++index) { | 
|  | double newT = start + (index / parts) * (end - start); | 
|  | if (newT > 0 && newT < 1) { | 
|  | ts->push_back(newT); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | static void toQuadraticTs(const SkDCubic* cubic, double precision, SkTArray<double, true>* ts) { | 
|  | SkReduceOrder reducer; | 
|  | int order = reducer.reduce(*cubic, SkReduceOrder::kAllow_Quadratics); | 
|  | if (order < 3) { | 
|  | return; | 
|  | } | 
|  | double inflectT[5]; | 
|  | int inflections = cubic->findInflections(inflectT); | 
|  | SkASSERT(inflections <= 2); | 
|  | if (!cubic->endsAreExtremaInXOrY()) { | 
|  | inflections += cubic->findMaxCurvature(&inflectT[inflections]); | 
|  | SkASSERT(inflections <= 5); | 
|  | } | 
|  | SkTQSort<double>(inflectT, &inflectT[inflections - 1]); | 
|  | // OPTIMIZATION: is this filtering common enough that it needs to be pulled out into its | 
|  | // own subroutine? | 
|  | while (inflections && approximately_less_than_zero(inflectT[0])) { | 
|  | memmove(inflectT, &inflectT[1], sizeof(inflectT[0]) * --inflections); | 
|  | } | 
|  | int start = 0; | 
|  | int next = 1; | 
|  | while (next < inflections) { | 
|  | if (!approximately_equal(inflectT[start], inflectT[next])) { | 
|  | ++start; | 
|  | ++next; | 
|  | continue; | 
|  | } | 
|  | memmove(&inflectT[start], &inflectT[next], sizeof(inflectT[0]) * (--inflections - start)); | 
|  | } | 
|  |  | 
|  | while (inflections && approximately_greater_than_one(inflectT[inflections - 1])) { | 
|  | --inflections; | 
|  | } | 
|  | SkDCubicPair pair; | 
|  | if (inflections == 1) { | 
|  | pair = cubic->chopAt(inflectT[0]); | 
|  | int orderP1 = reducer.reduce(pair.first(), SkReduceOrder::kNo_Quadratics); | 
|  | if (orderP1 < 2) { | 
|  | --inflections; | 
|  | } else { | 
|  | int orderP2 = reducer.reduce(pair.second(), SkReduceOrder::kNo_Quadratics); | 
|  | if (orderP2 < 2) { | 
|  | --inflections; | 
|  | } | 
|  | } | 
|  | } | 
|  | if (inflections == 0 && add_simple_ts(*cubic, precision, ts)) { | 
|  | return; | 
|  | } | 
|  | if (inflections == 1) { | 
|  | pair = cubic->chopAt(inflectT[0]); | 
|  | addTs(pair.first(), precision, 0, inflectT[0], ts); | 
|  | addTs(pair.second(), precision, inflectT[0], 1, ts); | 
|  | return; | 
|  | } | 
|  | if (inflections > 1) { | 
|  | SkDCubic part = cubic->subDivide(0, inflectT[0]); | 
|  | addTs(part, precision, 0, inflectT[0], ts); | 
|  | int last = inflections - 1; | 
|  | for (int idx = 0; idx < last; ++idx) { | 
|  | part = cubic->subDivide(inflectT[idx], inflectT[idx + 1]); | 
|  | addTs(part, precision, inflectT[idx], inflectT[idx + 1], ts); | 
|  | } | 
|  | part = cubic->subDivide(inflectT[last], 1); | 
|  | addTs(part, precision, inflectT[last], 1, ts); | 
|  | return; | 
|  | } | 
|  | addTs(*cubic, precision, 0, 1, ts); | 
|  | } | 
|  |  | 
|  | void CubicToQuads(const SkDCubic& cubic, double precision, SkTArray<SkDQuad, true>& quads) { | 
|  | SkTArray<double, true> ts; | 
|  | toQuadraticTs(&cubic, precision, &ts); | 
|  | if (ts.count() <= 0) { | 
|  | SkDQuad quad = cubic.toQuad(); | 
|  | quads.push_back(quad); | 
|  | return; | 
|  | } | 
|  | double tStart = 0; | 
|  | for (int i1 = 0; i1 <= ts.count(); ++i1) { | 
|  | const double tEnd = i1 < ts.count() ? ts[i1] : 1; | 
|  | SkDRect bounds; | 
|  | bounds.setBounds(cubic); | 
|  | SkDCubic part = cubic.subDivide(tStart, tEnd); | 
|  | SkDQuad quad = part.toQuad(); | 
|  | if (quad[1].fX < bounds.fLeft) { | 
|  | quad[1].fX = bounds.fLeft; | 
|  | } else if (quad[1].fX > bounds.fRight) { | 
|  | quad[1].fX = bounds.fRight; | 
|  | } | 
|  | if (quad[1].fY < bounds.fTop) { | 
|  | quad[1].fY = bounds.fTop; | 
|  | } else if (quad[1].fY > bounds.fBottom) { | 
|  | quad[1].fY = bounds.fBottom; | 
|  | } | 
|  | quads.push_back(quad); | 
|  | tStart = tEnd; | 
|  | } | 
|  | } | 
|  |  | 
|  | void CubicPathToQuads(const SkPath& cubicPath, SkPath* quadPath) { | 
|  | quadPath->reset(); | 
|  | SkDCubic cubic; | 
|  | SkTArray<SkDQuad, true> quads; | 
|  | SkPath::RawIter iter(cubicPath); | 
|  | uint8_t verb; | 
|  | SkPoint pts[4]; | 
|  | while ((verb = iter.next(pts)) != SkPath::kDone_Verb) { | 
|  | switch (verb) { | 
|  | case SkPath::kMove_Verb: | 
|  | quadPath->moveTo(pts[0].fX, pts[0].fY); | 
|  | continue; | 
|  | case SkPath::kLine_Verb: | 
|  | quadPath->lineTo(pts[1].fX, pts[1].fY); | 
|  | break; | 
|  | case SkPath::kQuad_Verb: | 
|  | quadPath->quadTo(pts[1].fX, pts[1].fY, pts[2].fX, pts[2].fY); | 
|  | break; | 
|  | case SkPath::kCubic_Verb: | 
|  | quads.reset(); | 
|  | cubic.set(pts); | 
|  | CubicToQuads(cubic, cubic.calcPrecision(), quads); | 
|  | for (int index = 0; index < quads.count(); ++index) { | 
|  | SkPoint qPts[2] = { | 
|  | quads[index][1].asSkPoint(), | 
|  | quads[index][2].asSkPoint() | 
|  | }; | 
|  | quadPath->quadTo(qPts[0].fX, qPts[0].fY, qPts[1].fX, qPts[1].fY); | 
|  | } | 
|  | break; | 
|  | case SkPath::kClose_Verb: | 
|  | quadPath->close(); | 
|  | break; | 
|  | default: | 
|  | SkDEBUGFAIL("bad verb"); | 
|  | return; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | void CubicPathToSimple(const SkPath& cubicPath, SkPath* simplePath) { | 
|  | simplePath->reset(); | 
|  | SkDCubic cubic; | 
|  | SkPath::RawIter iter(cubicPath); | 
|  | uint8_t verb; | 
|  | SkPoint pts[4]; | 
|  | while ((verb = iter.next(pts)) != SkPath::kDone_Verb) { | 
|  | switch (verb) { | 
|  | case SkPath::kMove_Verb: | 
|  | simplePath->moveTo(pts[0].fX, pts[0].fY); | 
|  | continue; | 
|  | case SkPath::kLine_Verb: | 
|  | simplePath->lineTo(pts[1].fX, pts[1].fY); | 
|  | break; | 
|  | case SkPath::kQuad_Verb: | 
|  | simplePath->quadTo(pts[1].fX, pts[1].fY, pts[2].fX, pts[2].fY); | 
|  | break; | 
|  | case SkPath::kCubic_Verb: { | 
|  | cubic.set(pts); | 
|  | double tInflects[2]; | 
|  | int inflections = cubic.findInflections(tInflects); | 
|  | if (inflections > 1 && tInflects[0] > tInflects[1]) { | 
|  | SkTSwap(tInflects[0], tInflects[1]); | 
|  | } | 
|  | double lo = 0; | 
|  | for (int index = 0; index <= inflections; ++index) { | 
|  | double hi = index < inflections ? tInflects[index] : 1; | 
|  | SkDCubic part = cubic.subDivide(lo, hi); | 
|  | SkPoint cPts[3]; | 
|  | cPts[0] = part[1].asSkPoint(); | 
|  | cPts[1] = part[2].asSkPoint(); | 
|  | cPts[2] = part[3].asSkPoint(); | 
|  | simplePath->cubicTo(cPts[0].fX, cPts[0].fY, cPts[1].fX, cPts[1].fY, | 
|  | cPts[2].fX, cPts[2].fY); | 
|  | lo = hi; | 
|  | } | 
|  | break; | 
|  | } | 
|  | case SkPath::kClose_Verb: | 
|  | simplePath->close(); | 
|  | break; | 
|  | default: | 
|  | SkDEBUGFAIL("bad verb"); | 
|  | return; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | static bool SkDoubleIsNaN(double x) { | 
|  | return x != x; | 
|  | } | 
|  |  | 
|  | bool ValidBounds(const SkPathOpsBounds& bounds) { | 
|  | if (SkScalarIsNaN(bounds.fLeft)) { | 
|  | return false; | 
|  | } | 
|  | if (SkScalarIsNaN(bounds.fTop)) { | 
|  | return false; | 
|  | } | 
|  | if (SkScalarIsNaN(bounds.fRight)) { | 
|  | return false; | 
|  | } | 
|  | return !SkScalarIsNaN(bounds.fBottom); | 
|  | } | 
|  |  | 
|  | bool ValidConic(const SkDConic& conic) { | 
|  | for (int index = 0; index < SkDConic::kPointCount; ++index) { | 
|  | if (!ValidPoint(conic[index])) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | if (SkDoubleIsNaN(conic.fWeight)) { | 
|  | return false; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ValidCubic(const SkDCubic& cubic) { | 
|  | for (int index = 0; index < 4; ++index) { | 
|  | if (!ValidPoint(cubic[index])) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ValidLine(const SkDLine& line) { | 
|  | for (int index = 0; index < 2; ++index) { | 
|  | if (!ValidPoint(line[index])) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ValidPoint(const SkDPoint& pt) { | 
|  | if (SkDoubleIsNaN(pt.fX)) { | 
|  | return false; | 
|  | } | 
|  | return !SkDoubleIsNaN(pt.fY); | 
|  | } | 
|  |  | 
|  | bool ValidPoints(const SkPoint* pts, int count) { | 
|  | for (int index = 0; index < count; ++index) { | 
|  | if (SkScalarIsNaN(pts[index].fX)) { | 
|  | return false; | 
|  | } | 
|  | if (SkScalarIsNaN(pts[index].fY)) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ValidQuad(const SkDQuad& quad) { | 
|  | for (int index = 0; index < 3; ++index) { | 
|  | if (!ValidPoint(quad[index])) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool ValidVector(const SkDVector& v) { | 
|  | if (SkDoubleIsNaN(v.fX)) { | 
|  | return false; | 
|  | } | 
|  | return !SkDoubleIsNaN(v.fY); | 
|  | } |