A game about forced loneliness, made by TACStudios
tacstudios.tngl.sh
1using System;
2using UnityEngine;
3
4namespace UnityEditor.U2D.Animation
5{
6 internal static class MathUtility
7 {
8 public static float DistanceToSegmentClamp(Vector3 p, Vector3 p1, Vector3 p2)
9 {
10 float l2 = (p2 - p1).sqrMagnitude; // i.e. |b-a|^2 - avoid a sqrt
11 if (l2 == 0.0)
12 return float.MaxValue; // a == b case
13 float t = Vector3.Dot(p - p1, p2 - p1) / l2;
14 if (t < 0.0)
15 return float.MaxValue; // Beyond the 'a' end of the segment
16 if (t > 1.0)
17 return float.MaxValue; // Beyond the 'b' end of the segment
18 Vector3 projection = p1 + t * (p2 - p1); // Projection falls on the segment
19 return (p - projection).magnitude;
20 }
21
22 public static Vector2 ClampPositionToRect(Vector2 position, Rect rect)
23 {
24 return new Vector2(Mathf.Clamp(position.x, rect.xMin, rect.xMax), Mathf.Clamp(position.y, rect.yMin, rect.yMax));
25 }
26
27 public static Vector2 MoveRectInsideFrame(Rect rect, Rect frame, Vector2 delta)
28 {
29 if (frame.size.x <= rect.size.x)
30 delta.x = 0f;
31
32 if (frame.size.y <= rect.size.y)
33 delta.y = 0f;
34
35 Vector2 min = rect.min + delta;
36 Vector2 max = rect.max + delta;
37 Vector2 size = rect.size;
38 Vector2 position = rect.position;
39
40 max.x = Mathf.Clamp(max.x, frame.min.x, frame.max.x);
41 max.y = Mathf.Clamp(max.y, frame.min.y, frame.max.y);
42
43 min = max - size;
44
45 min.x = Mathf.Clamp(min.x, frame.min.x, frame.max.x);
46 min.y = Mathf.Clamp(min.y, frame.min.y, frame.max.y);
47
48 max = min + size;
49
50 rect.min = min;
51 rect.max = max;
52
53 delta = rect.position - position;
54
55 return delta;
56 }
57
58 public static bool SegmentIntersection(Vector2 p0, Vector2 p1, Vector2 p2, Vector2 p3, ref Vector2 point)
59 {
60 Vector2 s1 = p1 - p0;
61 Vector2 s2 = p3 - p2;
62
63 float s, t, determinant;
64 determinant = (s1.x * s2.y - s2.x * s1.y);
65
66 if (Mathf.Approximately(determinant, 0f))
67 return false;
68
69 s = (-s1.y * (p0.x - p2.x) + s1.x * (p0.y - p2.y)) / determinant;
70 t = (s2.x * (p0.y - p2.y) - s2.y * (p0.x - p2.x)) / determinant;
71
72 if (s >= 0f && s <= 1f && t >= 0f && t <= 1f)
73 {
74 point = p0 + (t * s1);
75 return true;
76 }
77
78 return false;
79 }
80
81 //https://gamedev.stackexchange.com/a/49370
82 public static void Barycentric(Vector2 p, Vector2 a, Vector2 b, Vector2 c, out Vector3 coords)
83 {
84 Vector2 v0 = b - a, v1 = c - a, v2 = p - a;
85 float d00 = Vector2.Dot(v0, v0);
86 float d01 = Vector2.Dot(v0, v1);
87 float d11 = Vector2.Dot(v1, v1);
88 float d20 = Vector2.Dot(v2, v0);
89 float d21 = Vector2.Dot(v2, v1);
90 float invDenom = 1f / (d00 * d11 - d01 * d01);
91 coords.y = (d11 * d20 - d01 * d21) * invDenom;
92 coords.z = (d00 * d21 - d01 * d20) * invDenom;
93 coords.x = 1f - coords.y - coords.z;
94 }
95
96 public static Quaternion NormalizeQuaternion(Quaternion q)
97 {
98 Vector4 v = new Vector4(q.x, q.y, q.z, q.w).normalized;
99 return new Quaternion(v.x, v.y, v.z, v.w);
100 }
101
102 //From: https://answers.unity.com/questions/861719/a-fast-triangle-triangle-intersection-algorithm-fo.html
103 public static bool Intersect(Vector3 p1, Vector3 p2, Vector3 p3, Ray ray)
104 {
105 Vector3 e1, e2;
106 Vector3 p, q, t;
107 float det, invDet, u, v;
108 e1 = p2 - p1;
109 e2 = p3 - p1;
110 p = Vector3.Cross(ray.direction, e2);
111 det = Vector3.Dot(e1, p);
112
113 if (Mathf.Approximately(det, 0f))
114 return false;
115
116 invDet = 1.0f / det;
117
118 t = ray.origin - p1;
119 u = Vector3.Dot(t, p) * invDet;
120
121 if (u < 0 || u > 1)
122 return false;
123
124 q = Vector3.Cross(t, e1);
125 v = Vector3.Dot(ray.direction, q) * invDet;
126
127 if (v < 0 || u + v > 1)
128 return false;
129
130 if ((Vector3.Dot(e2, q) * invDet) > 0f)
131 return true;
132
133 return false;
134 }
135 }
136}