chromium/third_party/skia/src/gpu/ganesh/geometry/GrPathUtils.cpp

/*
 * Copyright 2011 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "src/gpu/ganesh/geometry/GrPathUtils.h"

#include "include/core/SkMatrix.h"
#include "include/core/SkRect.h"
#include "include/private/base/SkAssert.h"
#include "include/private/base/SkFloatingPoint.h"
#include "src/core/SkGeometry.h"
#include "src/core/SkPathEnums.h"
#include "src/core/SkPointPriv.h"
#include "src/gpu/tessellate/WangsFormula.h"

#include <algorithm>

usingnamespaceskia_private;

static const SkScalar kMinCurveTol = …;

static float tolerance_to_wangs_precision(float srcTol) { … }

uint32_t max_bezier_vertices(uint32_t chopCount) { … }

SkScalar GrPathUtils::scaleToleranceToSrc(SkScalar devTol,
                                          const SkMatrix& viewM,
                                          const SkRect& pathBounds) { … }

uint32_t GrPathUtils::quadraticPointCount(const SkPoint points[], SkScalar tol) { … }

uint32_t GrPathUtils::generateQuadraticPoints(const SkPoint& p0,
                                              const SkPoint& p1,
                                              const SkPoint& p2,
                                              SkScalar tolSqd,
                                              SkPoint** points,
                                              uint32_t pointsLeft) { … }

uint32_t GrPathUtils::cubicPointCount(const SkPoint points[], SkScalar tol) { … }

uint32_t GrPathUtils::generateCubicPoints(const SkPoint& p0,
                                          const SkPoint& p1,
                                          const SkPoint& p2,
                                          const SkPoint& p3,
                                          SkScalar tolSqd,
                                          SkPoint** points,
                                          uint32_t pointsLeft) { … }

void GrPathUtils::QuadUVMatrix::set(const SkPoint qPts[3]) { … }

////////////////////////////////////////////////////////////////////////////////

// k = (y2 - y0, x0 - x2, x2*y0 - x0*y2)
// l = (y1 - y0, x0 - x1, x1*y0 - x0*y1) * 2*w
// m = (y2 - y1, x1 - x2, x2*y1 - x1*y2) * 2*w
void GrPathUtils::getConicKLM(const SkPoint p[3], const SkScalar weight, SkMatrix* out) { … }

////////////////////////////////////////////////////////////////////////////////

namespace {

// a is the first control point of the cubic.
// ab is the vector from a to the second control point.
// dc is the vector from the fourth to the third control point.
// d is the fourth control point.
// p is the candidate quadratic control point.
// this assumes that the cubic doesn't inflect and is simple
bool is_point_within_cubic_tangents(const SkPoint& a,
                                    const SkVector& ab,
                                    const SkVector& dc,
                                    const SkPoint& d,
                                    SkPathFirstDirection dir,
                                    const SkPoint p) { … }

void convert_noninflect_cubic_to_quads(const SkPoint p[4],
                                       SkScalar toleranceSqd,
                                       TArray<SkPoint, true>* quads,
                                       int sublevel = 0,
                                       bool preserveFirstTangent = true,
                                       bool preserveLastTangent = true) { … }

void convert_noninflect_cubic_to_quads_with_constraint(const SkPoint p[4],
                                                       SkScalar toleranceSqd,
                                                       SkPathFirstDirection dir,
                                                       TArray<SkPoint, true>* quads,
                                                       int sublevel = 0) { … }
}  // namespace

void GrPathUtils::convertCubicToQuads(const SkPoint p[4],
                                      SkScalar tolScale,
                                      TArray<SkPoint, true>* quads) { … }

void GrPathUtils::convertCubicToQuadsConstrainToTangents(const SkPoint p[4],
                                                         SkScalar tolScale,
                                                         SkPathFirstDirection dir,
                                                         TArray<SkPoint, true>* quads) { … }