113 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			113 lines
		
	
	
		
			3.9 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /**************************************************************************/
 | |
| /*  triangle2.cpp                                                         */
 | |
| /**************************************************************************/
 | |
| /*                         This file is part of:                          */
 | |
| /*                             GODOT ENGINE                               */
 | |
| /*                        https://godotengine.org                         */
 | |
| /**************************************************************************/
 | |
| /* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
 | |
| /* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
 | |
| /*                                                                        */
 | |
| /* Permission is hereby granted, free of charge, to any person obtaining  */
 | |
| /* a copy of this software and associated documentation files (the        */
 | |
| /* "Software"), to deal in the Software without restriction, including    */
 | |
| /* without limitation the rights to use, copy, modify, merge, publish,    */
 | |
| /* distribute, sublicense, and/or sell copies of the Software, and to     */
 | |
| /* permit persons to whom the Software is furnished to do so, subject to  */
 | |
| /* the following conditions:                                              */
 | |
| /*                                                                        */
 | |
| /* The above copyright notice and this permission notice shall be         */
 | |
| /* included in all copies or substantial portions of the Software.        */
 | |
| /*                                                                        */
 | |
| /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
 | |
| /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
 | |
| /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
 | |
| /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
 | |
| /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
 | |
| /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
 | |
| /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
 | |
| /**************************************************************************/
 | |
| 
 | |
| #include "triangle2.h"
 | |
| 
 | |
| Vector2 Triangle2::get_random_point_inside() const {
 | |
| 	real_t a = Math::random(0.0, 1.0);
 | |
| 	real_t b = Math::random(0.0, 1.0);
 | |
| 	if (a > b) {
 | |
| 		SWAP(a, b);
 | |
| 	}
 | |
| 
 | |
| 	return vertex[0] * a + vertex[1] * (b - a) + vertex[2] * (1.0f - b);
 | |
| }
 | |
| 
 | |
| Vector2 Triangle2::get_closest_point_to(const Vector2 &p_point) const {
 | |
| 	Vector2 edge0 = vertex[1] - vertex[0];
 | |
| 	Vector2 edge1 = vertex[2] - vertex[0];
 | |
| 	Vector2 v0 = vertex[0] - p_point;
 | |
| 
 | |
| 	real_t a = edge0.dot(edge0);
 | |
| 	real_t b = edge0.dot(edge1);
 | |
| 	real_t c = edge1.dot(edge1);
 | |
| 	real_t d = edge0.dot(v0);
 | |
| 	real_t e = edge1.dot(v0);
 | |
| 
 | |
| 	real_t det = a * c - b * b;
 | |
| 	real_t s = b * e - c * d;
 | |
| 	real_t t = b * d - a * e;
 | |
| 
 | |
| 	if (s + t < det) {
 | |
| 		if (s < 0.f) {
 | |
| 			if (t < 0.f) {
 | |
| 				if (d < 0.f) {
 | |
| 					s = CLAMP(-d / a, 0.f, 1.f);
 | |
| 					t = 0.f;
 | |
| 				} else {
 | |
| 					s = 0.f;
 | |
| 					t = CLAMP(-e / c, 0.f, 1.f);
 | |
| 				}
 | |
| 			} else {
 | |
| 				s = 0.f;
 | |
| 				t = CLAMP(-e / c, 0.f, 1.f);
 | |
| 			}
 | |
| 		} else if (t < 0.f) {
 | |
| 			s = CLAMP(-d / a, 0.f, 1.f);
 | |
| 			t = 0.f;
 | |
| 		} else {
 | |
| 			real_t inv_det = 1.f / det;
 | |
| 			s *= inv_det;
 | |
| 			t *= inv_det;
 | |
| 		}
 | |
| 	} else {
 | |
| 		if (s < 0.f) {
 | |
| 			real_t tmp0 = b + d;
 | |
| 			real_t tmp1 = c + e;
 | |
| 			if (tmp1 > tmp0) {
 | |
| 				real_t numer = tmp1 - tmp0;
 | |
| 				real_t denom = a - 2 * b + c;
 | |
| 				s = CLAMP(numer / denom, 0.f, 1.f);
 | |
| 				t = 1 - s;
 | |
| 			} else {
 | |
| 				t = CLAMP(-e / c, 0.f, 1.f);
 | |
| 				s = 0.f;
 | |
| 			}
 | |
| 		} else if (t < 0.f) {
 | |
| 			if (a + d > b + e) {
 | |
| 				real_t numer = c + e - b - d;
 | |
| 				real_t denom = a - 2 * b + c;
 | |
| 				s = CLAMP(numer / denom, 0.f, 1.f);
 | |
| 				t = 1 - s;
 | |
| 			} else {
 | |
| 				s = CLAMP(-d / a, 0.f, 1.f);
 | |
| 				t = 0.f;
 | |
| 			}
 | |
| 		} else {
 | |
| 			real_t numer = c + e - b - d;
 | |
| 			real_t denom = a - 2 * b + c;
 | |
| 			s = CLAMP(numer / denom, 0.f, 1.f);
 | |
| 			t = 1.f - s;
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	return vertex[0] + s * edge0 + t * edge1;
 | |
| }
 | 
