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/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkIntersections_DEFINE
#define SkIntersections_DEFINE
#include "SkPathOpsConic.h"
#include "SkPathOpsCubic.h"
#include "SkPathOpsLine.h"
#include "SkPathOpsPoint.h"
#include "SkPathOpsQuad.h"
class SkIntersections {
public:
SkIntersections()
: fSwap(0)
#ifdef SK_DEBUG
, fDepth(0)
#endif
{
sk_bzero(fPt, sizeof(fPt));
sk_bzero(fPt2, sizeof(fPt2));
sk_bzero(fT, sizeof(fT));
sk_bzero(fNearlySame, sizeof(fNearlySame));
#if DEBUG_T_SECT_LOOP_COUNT
sk_bzero(fDebugLoopCount, sizeof(fDebugLoopCount));
#endif
reset();
fMax = 0; // require that the caller set the max
}
class TArray {
public:
explicit TArray(const double ts[10]) : fTArray(ts) {}
double operator[](int n) const {
return fTArray[n];
}
const double* fTArray;
};
TArray operator[](int n) const { return TArray(fT[n]); }
void allowNear(bool nearAllowed) {
fAllowNear = nearAllowed;
}
void clearCoincidence(int index) {
SkASSERT(index >= 0);
int bit = 1 << index;
fIsCoincident[0] &= ~bit;
fIsCoincident[1] &= ~bit;
}
int conicHorizontal(const SkPoint a[3], SkScalar weight, SkScalar left, SkScalar right,
SkScalar y, bool flipped) {
SkDConic conic;
conic.set(a, weight);
fMax = 2;
return horizontal(conic, left, right, y, flipped);
}
int conicVertical(const SkPoint a[3], SkScalar weight, SkScalar top, SkScalar bottom,
SkScalar x, bool flipped) {
SkDConic conic;
conic.set(a, weight);
fMax = 2;
return vertical(conic, top, bottom, x, flipped);
}
int conicLine(const SkPoint a[3], SkScalar weight, const SkPoint b[2]) {
SkDConic conic;
conic.set(a, weight);
SkDLine line;
line.set(b);
fMax = 3; // 2; permit small coincident segment + non-coincident intersection
return intersect(conic, line);
}
int cubicHorizontal(const SkPoint a[4], SkScalar left, SkScalar right, SkScalar y,
bool flipped) {
SkDCubic cubic;
cubic.set(a);
fMax = 3;
return horizontal(cubic, left, right, y, flipped);
}
int cubicVertical(const SkPoint a[4], SkScalar top, SkScalar bottom, SkScalar x, bool flipped) {
SkDCubic cubic;
cubic.set(a);
fMax = 3;
return vertical(cubic, top, bottom, x, flipped);
}
int cubicLine(const SkPoint a[4], const SkPoint b[2]) {
SkDCubic cubic;
cubic.set(a);
SkDLine line;
line.set(b);
fMax = 3;
return intersect(cubic, line);
}
bool hasT(double t) const {
SkASSERT(t == 0 || t == 1);
return fUsed > 0 && (t == 0 ? fT[0][0] == 0 : fT[0][fUsed - 1] == 1);
}
int insertSwap(double one, double two, const SkDPoint& pt) {
if (fSwap) {
return insert(two, one, pt);
} else {
return insert(one, two, pt);
}
}
bool isCoincident(int index) {
return (fIsCoincident[0] & 1 << index) != 0;
}
int lineHorizontal(const SkPoint a[2], SkScalar left, SkScalar right, SkScalar y,
bool flipped) {
SkDLine line;
line.set(a);
fMax = 2;
return horizontal(line, left, right, y, flipped);
}
int lineVertical(const SkPoint a[2], SkScalar top, SkScalar bottom, SkScalar x, bool flipped) {
SkDLine line;
line.set(a);
fMax = 2;
return vertical(line, top, bottom, x, flipped);
}
int lineLine(const SkPoint a[2], const SkPoint b[2]) {
SkDLine aLine, bLine;
aLine.set(a);
bLine.set(b);
fMax = 2;
return intersect(aLine, bLine);
}
bool nearlySame(int index) const {
SkASSERT(index == 0 || index == 1);
return fNearlySame[index];
}
const SkDPoint& pt(int index) const {
return fPt[index];
}
const SkDPoint& pt2(int index) const {
return fPt2[index];
}
int quadHorizontal(const SkPoint a[3], SkScalar left, SkScalar right, SkScalar y,
bool flipped) {
SkDQuad quad;
quad.set(a);
fMax = 2;
return horizontal(quad, left, right, y, flipped);
}
int quadVertical(const SkPoint a[3], SkScalar top, SkScalar bottom, SkScalar x, bool flipped) {
SkDQuad quad;
quad.set(a);
fMax = 2;
return vertical(quad, top, bottom, x, flipped);
}
int quadLine(const SkPoint a[3], const SkPoint b[2]) {
SkDQuad quad;
quad.set(a);
SkDLine line;
line.set(b);
fMax = 3; // 2; permit small coincident segment + non-coincident intersection
return intersect(quad, line);
}
// leaves swap, max alone
void reset() {
fAllowNear = true;
fUsed = 0;
sk_bzero(fIsCoincident, sizeof(fIsCoincident));
}
void set(bool swap, int tIndex, double t) {
fT[(int) swap][tIndex] = t;
}
void setMax(int max) {
SkASSERT(max <= (int) SK_ARRAY_COUNT(fPt));
fMax = max;
}
void swap() {
fSwap ^= true;
}
bool swapped() const {
return fSwap;
}
int used() const {
return fUsed;
}
void downDepth() {
SkASSERT(--fDepth >= 0);
}
bool unBumpT(int index) {
SkASSERT(fUsed == 1);
fT[0][index] = fT[0][index] * (1 + BUMP_EPSILON * 2) - BUMP_EPSILON;
if (!between(0, fT[0][index], 1)) {
fUsed = 0;
return false;
}
return true;
}
void upDepth() {
SkASSERT(++fDepth < 16);
}
void alignQuadPts(const SkPoint a[3], const SkPoint b[3]);
int cleanUpCoincidence();
int closestTo(double rangeStart, double rangeEnd, const SkDPoint& testPt, double* dist) const;
void cubicInsert(double one, double two, const SkDPoint& pt, const SkDCubic& c1,
const SkDCubic& c2);
void flip();
int horizontal(const SkDLine&, double left, double right, double y, bool flipped);
int horizontal(const SkDQuad&, double left, double right, double y, bool flipped);
int horizontal(const SkDQuad&, double left, double right, double y, double tRange[2]);
int horizontal(const SkDCubic&, double y, double tRange[3]);
int horizontal(const SkDConic&, double left, double right, double y, bool flipped);
int horizontal(const SkDCubic&, double left, double right, double y, bool flipped);
int horizontal(const SkDCubic&, double left, double right, double y, double tRange[3]);
static double HorizontalIntercept(const SkDLine& line, double y);
static int HorizontalIntercept(const SkDQuad& quad, SkScalar y, double* roots);
static int HorizontalIntercept(const SkDConic& conic, SkScalar y, double* roots);
// FIXME : does not respect swap
int insert(double one, double two, const SkDPoint& pt);
void insertNear(double one, double two, const SkDPoint& pt1, const SkDPoint& pt2);
// start if index == 0 : end if index == 1
int insertCoincident(double one, double two, const SkDPoint& pt);
int intersect(const SkDLine&, const SkDLine&);
int intersect(const SkDQuad&, const SkDLine&);
int intersect(const SkDQuad&, const SkDQuad&);
int intersect(const SkDConic&, const SkDLine&);
int intersect(const SkDConic&, const SkDQuad&);
int intersect(const SkDConic&, const SkDConic&);
int intersect(const SkDCubic&, const SkDLine&);
int intersect(const SkDCubic&, const SkDQuad&);
int intersect(const SkDCubic&, const SkDConic&);
int intersect(const SkDCubic&, const SkDCubic&);
int intersectRay(const SkDLine&, const SkDLine&);
int intersectRay(const SkDQuad&, const SkDLine&);
int intersectRay(const SkDConic&, const SkDLine&);
int intersectRay(const SkDCubic&, const SkDLine&);
void merge(const SkIntersections& , int , const SkIntersections& , int );
int mostOutside(double rangeStart, double rangeEnd, const SkDPoint& origin) const;
void removeOne(int index);
void setCoincident(int index);
int vertical(const SkDLine&, double top, double bottom, double x, bool flipped);
int vertical(const SkDQuad&, double top, double bottom, double x, bool flipped);
int vertical(const SkDConic&, double top, double bottom, double x, bool flipped);
int vertical(const SkDCubic&, double top, double bottom, double x, bool flipped);
static double VerticalIntercept(const SkDLine& line, double x);
static int VerticalIntercept(const SkDQuad& quad, SkScalar x, double* roots);
static int VerticalIntercept(const SkDConic& conic, SkScalar x, double* roots);
int depth() const {
#ifdef SK_DEBUG
return fDepth;
#else
return 0;
#endif
}
enum DebugLoop {
kIterations_DebugLoop,
kCoinCheck_DebugLoop,
kComputePerp_DebugLoop,
};
void debugBumpLoopCount(DebugLoop );
int debugCoincidentUsed() const;
int debugLoopCount(DebugLoop ) const;
void debugResetLoopCount();
void dump() const; // implemented for testing only
private:
bool cubicCheckCoincidence(const SkDCubic& c1, const SkDCubic& c2);
bool cubicExactEnd(const SkDCubic& cubic1, bool start, const SkDCubic& cubic2);
void cubicNearEnd(const SkDCubic& cubic1, bool start, const SkDCubic& cubic2, const SkDRect& );
void cleanUpParallelLines(bool parallel);
void computePoints(const SkDLine& line, int used);
SkDPoint fPt[12]; // FIXME: since scans store points as SkPoint, this should also
SkDPoint fPt2[2]; // used by nearly same to store alternate intersection point
double fT[2][12];
uint16_t fIsCoincident[2]; // bit set for each curve's coincident T
bool fNearlySame[2]; // true if end points nearly match
unsigned char fUsed;
unsigned char fMax;
bool fAllowNear;
bool fSwap;
#ifdef SK_DEBUG
int fDepth;
#endif
#if DEBUG_T_SECT_LOOP_COUNT
int fDebugLoopCount[3];
#endif
};
#endif