| /* |
| * 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; |
| } |
| } |
| |
| 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 |