comparison: src/geometry.cpp
src/geometry.cpp
- changeset 168
- 24590af32ad6
- parent 123
- e3fe3617b631
- child 187
- 30204975694a
equal
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inserted
replaced
| 167:c1ff4f107569 | 168:24590af32ad6 |
|---|---|
| 215 [&crosses](const glm::vec3& vector) | 215 [&crosses](const glm::vec3& vector) |
| 216 { | 216 { |
| 217 return glm::dot(crosses[0], vector) < 1e-6; | 217 return glm::dot(crosses[0], vector) < 1e-6; |
| 218 }); | 218 }); |
| 219 } | 219 } |
| 220 | |
| 221 /** | |
| 222 * @brief Determines the winding of a 2d polygon | |
| 223 * @param polygon | |
| 224 * @return winding | |
| 225 */ | |
| 226 Winding geom::winding(const QPolygonF &polygon) | |
| 227 { | |
| 228 // based on https://stackoverflow.com/a/1165943 | |
| 229 double sum = 0.0; | |
| 230 for (int i = 0; i < polygon.size(); i += 1) | |
| 231 { | |
| 232 const QPointF& p1 = polygon[i]; | |
| 233 const QPointF& p2 = polygon[(i + 1) % polygon.size()]; | |
| 234 sum += (p2.x() - p1.x()) * (p2.y() + p1.y()); | |
| 235 } | |
| 236 return (sum < 0) ? Winding::Anticlockwise : Winding::Clockwise; | |
| 237 } |
