skia2/experimental/Intersection/Intersections.h
caryclark@google.com 7ff5c841bf shape ops work in progress
git-svn-id: http://skia.googlecode.com/svn/trunk@7864 2bbb7eff-a529-9590-31e7-b0007b416f81
2013-02-26 15:56:05 +00:00

145 lines
3.1 KiB
C++

/*
* 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 Intersections_DEFINE
#define Intersections_DEFINE
class Intersections {
public:
Intersections()
: fFlip(0)
#if SK_DEBUG
, fDepth(0)
#endif
, fSwap(0)
{
#if SK_DEBUG
bzero(fPt, sizeof(fPt));
bzero(fT, sizeof(fT));
bzero(fIsCoincident, sizeof(fIsCoincident));
#endif
reset();
}
int coincidentUsed() const {
if (!fIsCoincident[0]) {
SkASSERT(!fIsCoincident[0]);
return 0;
}
int count = 0;
SkDEBUGCODE(int count2 = 0;)
for (int index = 0; index < fUsed; ++index) {
if (fIsCoincident[0] & (1 << index)) {
++count;
}
#if SK_DEBUG
if (fIsCoincident[1] & (1 << index)) {
++count2;
}
#endif
}
SkASSERT(count == count2);
return count;
}
void offset(int base, double start, double end) {
for (int index = base; index < fUsed; ++index) {
double val = fT[fSwap][index];
val *= end - start;
val += start;
fT[fSwap][index] = val;
}
}
// FIXME : does not respect swap
int insert(double one, double two, const _Point& pt);
// start if index == 0 : end if index == 1
void insertCoincident(double one, double two, const _Point& pt) {
int index = insertSwap(one, two, pt);
int bit = 1 << index;
fIsCoincident[0] |= bit;
fIsCoincident[1] |= bit;
}
void insertCoincidentPair(double s1, double e1, double s2, double e2,
const _Point& startPt, const _Point& endPt);
int insertSwap(double one, double two, const _Point& pt) {
if (fSwap) {
return insert(two, one, pt);
} else {
return insert(one, two, pt);
}
}
bool intersected() const {
return fUsed > 0;
}
void removeOne(int index);
// leaves flip, swap alone
void reset() {
fUsed = 0;
fUnsortable = false;
}
void swap() {
fSwap ^= true;
}
void swapPts() {
int index;
for (index = 0; index < fUsed; ++index) {
SkTSwap(fT[0][index], fT[1][index]);
}
}
bool swapped() const {
return fSwap;
}
bool unsortable() const {
return fUnsortable;
}
int used() const {
return fUsed;
}
void downDepth() {
SkASSERT(--fDepth >= 0);
}
void upDepth() {
SkASSERT(++fDepth < 16);
}
#if SK_DEBUG
int depth() const {
return fDepth;
}
#endif
_Point fPt[9];
double fT[2][9];
unsigned short fIsCoincident[2]; // bit arrays, one bit set for each coincident T
unsigned char fUsed;
bool fFlip;
bool fUnsortable;
#if SK_DEBUG
int fDepth;
#endif
protected:
// used by addCoincident to remove ordinary intersections in range
void remove(double one, double two, const _Point& startPt, const _Point& endPt);
private:
bool fSwap;
};
#endif