| 25 | } |
| 26 | |
| 27 | double Scanline::overlap(const Scanline &a, const Scanline &b, double xFrom, double xTo, FillRule fillRule) { |
| 28 | double total = 0; |
| 29 | bool aInside = false, bInside = false; |
| 30 | int ai = 0, bi = 0; |
| 31 | double ax = !a.intersections.empty() ? a.intersections[ai].x : xTo; |
| 32 | double bx = !b.intersections.empty() ? b.intersections[bi].x : xTo; |
| 33 | while (ax < xFrom || bx < xFrom) { |
| 34 | double xNext = min(ax, bx); |
| 35 | if (ax == xNext && ai < (int) a.intersections.size()) { |
| 36 | aInside = interpretFillRule(a.intersections[ai].direction, fillRule); |
| 37 | ax = ++ai < (int) a.intersections.size() ? a.intersections[ai].x : xTo; |
| 38 | } |
| 39 | if (bx == xNext && bi < (int) b.intersections.size()) { |
| 40 | bInside = interpretFillRule(b.intersections[bi].direction, fillRule); |
| 41 | bx = ++bi < (int) b.intersections.size() ? b.intersections[bi].x : xTo; |
| 42 | } |
| 43 | } |
| 44 | double x = xFrom; |
| 45 | while (ax < xTo || bx < xTo) { |
| 46 | double xNext = min(ax, bx); |
| 47 | if (aInside == bInside) |
| 48 | total += xNext-x; |
| 49 | if (ax == xNext && ai < (int) a.intersections.size()) { |
| 50 | aInside = interpretFillRule(a.intersections[ai].direction, fillRule); |
| 51 | ax = ++ai < (int) a.intersections.size() ? a.intersections[ai].x : xTo; |
| 52 | } |
| 53 | if (bx == xNext && bi < (int) b.intersections.size()) { |
| 54 | bInside = interpretFillRule(b.intersections[bi].direction, fillRule); |
| 55 | bx = ++bi < (int) b.intersections.size() ? b.intersections[bi].x : xTo; |
| 56 | } |
| 57 | x = xNext; |
| 58 | } |
| 59 | if (aInside == bInside) |
| 60 | total += xTo-x; |
| 61 | return total; |
| 62 | } |
| 63 | |
| 64 | Scanline::Scanline() : lastIndex(0) { } |
| 65 |
nothing calls this directly
no test coverage detected