1 /* gph-cmath - C graphics math library
2 * Copyright (C) 2018-2023 John Tsiombikas <nuclear@member.fsf.org>
4 * This program is free software. Feel free to use, modify, and/or redistribute
5 * it under the terms of the MIT/X11 license. See LICENSE for details.
6 * If you intend to redistribute parts of the code without the LICENSE file
7 * replace this paragraph with the full contents of the LICENSE file.
9 static CGM_INLINE void cgm_vcons(cgm_vec3 *v, float x, float y, float z)
16 static CGM_INLINE cgm_vec3 cgm_vvec(float x, float y, float z)
25 static CGM_INLINE void cgm_vadd(cgm_vec3 *a, const cgm_vec3 *b)
32 static CGM_INLINE void cgm_vadd_scaled(cgm_vec3 *a, const cgm_vec3 *b, float s)
39 static CGM_INLINE void cgm_vsub(cgm_vec3 *a, const cgm_vec3 *b)
46 static CGM_INLINE void cgm_vsub_scaled(cgm_vec3 *a, const cgm_vec3 *b, float s)
53 static CGM_INLINE void cgm_vmul(cgm_vec3 *a, const cgm_vec3 *b)
60 static CGM_INLINE void cgm_vscale(cgm_vec3 *v, float s)
67 static CGM_INLINE void cgm_vmul_m4v3(cgm_vec3 *v, const float *m)
69 float x = v->x * m[0] + v->y * m[4] + v->z * m[8] + m[12];
70 float y = v->x * m[1] + v->y * m[5] + v->z * m[9] + m[13];
71 v->z = v->x * m[2] + v->y * m[6] + v->z * m[10] + m[14];
76 static CGM_INLINE void cgm_vmul_v3m4(cgm_vec3 *v, const float *m)
78 float x = v->x * m[0] + v->y * m[1] + v->z * m[2] + m[3];
79 float y = v->x * m[4] + v->y * m[5] + v->z * m[6] + m[7];
80 v->z = v->x * m[8] + v->y * m[9] + v->z * m[10] + m[11];
85 static CGM_INLINE void cgm_vmul_m3v3(cgm_vec3 *v, const float *m)
87 float x = v->x * m[0] + v->y * m[4] + v->z * m[8];
88 float y = v->x * m[1] + v->y * m[5] + v->z * m[9];
89 v->z = v->x * m[2] + v->y * m[6] + v->z * m[10];
94 static CGM_INLINE void cgm_vmul_v3m3(cgm_vec3 *v, const float *m)
96 float x = v->x * m[0] + v->y * m[1] + v->z * m[2];
97 float y = v->x * m[4] + v->y * m[5] + v->z * m[6];
98 v->z = v->x * m[8] + v->y * m[9] + v->z * m[10];
103 static CGM_INLINE float cgm_vdot(const cgm_vec3 *a, const cgm_vec3 *b)
105 return a->x * b->x + a->y * b->y + a->z * b->z;
108 static CGM_INLINE void cgm_vcross(cgm_vec3 *res, const cgm_vec3 *a, const cgm_vec3 *b)
110 res->x = a->y * b->z - a->z * b->y;
111 res->y = a->z * b->x - a->x * b->z;
112 res->z = a->x * b->y - a->y * b->x;
115 static CGM_INLINE float cgm_vlength(const cgm_vec3 *v)
117 return sqrt(v->x * v->x + v->y * v->y + v->z * v->z);
120 static CGM_INLINE float cgm_vlength_sq(const cgm_vec3 *v)
122 return v->x * v->x + v->y * v->y + v->z * v->z;
125 static CGM_INLINE float cgm_vdist(const cgm_vec3 *a, const cgm_vec3 *b)
127 float dx = a->x - b->x;
128 float dy = a->y - b->y;
129 float dz = a->z - b->z;
130 return sqrt(dx * dx + dy * dy + dz * dz);
133 static CGM_INLINE float cgm_vdist_sq(const cgm_vec3 *a, const cgm_vec3 *b)
135 float dx = a->x - b->x;
136 float dy = a->y - b->y;
137 float dz = a->z - b->z;
138 return dx * dx + dy * dy + dz * dz;
141 static CGM_INLINE void cgm_vnormalize(cgm_vec3 *v)
143 float len = cgm_vlength(v);
145 float s = 1.0f / len;
152 static CGM_INLINE void cgm_vreflect(cgm_vec3 *v, const cgm_vec3 *n)
154 float ndotv2 = cgm_vdot(v, n) * 2.0f;
155 v->x -= n->x * ndotv2;
156 v->y -= n->y * ndotv2;
157 v->z -= n->z * ndotv2;
160 static CGM_INLINE void cgm_vrefract(cgm_vec3 *v, const cgm_vec3 *n, float ior)
162 float ndotv = cgm_vdot(v, n);
163 float k = 1.0f - ior * ior * (1.0f - ndotv * ndotv);
165 cgm_vreflect(v, n); /* TIR */
167 float sqrt_k = sqrt(k);
168 v->x = ior * v->x - (ior * ndotv + sqrt_k) * n->x;
169 v->y = ior * v->y - (ior * ndotv + sqrt_k) * n->y;
170 v->z = ior * v->z - (ior * ndotv + sqrt_k) * n->z;
174 static CGM_INLINE void cgm_vrotate_quat(cgm_vec3 *v, const cgm_quat *q)
176 cgm_quat vq, inv_q = *q, tmp_q = *q;
178 cgm_qcons(&vq, v->x, v->y, v->z, 0.0f);
180 cgm_qmul(&tmp_q, &vq);
181 cgm_qmul(&tmp_q, &inv_q);
182 cgm_vcons(v, tmp_q.x, tmp_q.y, tmp_q.z);
185 static CGM_INLINE void cgm_vrotate_axis(cgm_vec3 *v, int axis, float angle)
188 cgm_mrotation_axis(m, axis, angle);
192 static CGM_INLINE void cgm_vrotate(cgm_vec3 *v, float angle, float x, float y, float z)
195 cgm_mrotation(m, angle, x, y, z);
199 static CGM_INLINE void cgm_vrotate_euler(cgm_vec3 *v, float a, float b, float c, enum cgm_euler_mode mode)
202 cgm_mrotation_euler(m, a, b, c, mode);
206 static CGM_INLINE void cgm_vlerp(cgm_vec3 *res, const cgm_vec3 *a, const cgm_vec3 *b, float t)
208 res->x = a->x + (b->x - a->x) * t;
209 res->y = a->y + (b->y - a->y) * t;
210 res->z = a->z + (b->z - a->z) * t;