godot-module-template/engine/modules/navigation_2d/triangle2.cpp
2025-04-12 18:40:44 +02:00

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;
}