ScrapExplorer - linmath.h
Home / ext / glfw / deps Lines: 1 | Size: 14123 bytes [Download] [Show on GitHub] [Search similar files] [Raw] [Raw (proxy)][FILE BEGIN]1#ifndef LINMATH_H 2#define LINMATH_H 3 4#include <string.h> 5#include <math.h> 6#include <string.h> 7 8/* 2021-03-21 Camilla Löwy <[email protected]> 9 * - Replaced double constants with float equivalents 10 */ 11 12#ifdef LINMATH_NO_INLINE 13#define LINMATH_H_FUNC static 14#else 15#define LINMATH_H_FUNC static inline 16#endif 17 18#define LINMATH_H_DEFINE_VEC(n) \ 19typedef float vec##n[n]; \ 20LINMATH_H_FUNC void vec##n##_add(vec##n r, vec##n const a, vec##n const b) \ 21{ \ 22 int i; \ 23 for(i=0; i<n; ++i) \ 24 r[i] = a[i] + b[i]; \ 25} \ 26LINMATH_H_FUNC void vec##n##_sub(vec##n r, vec##n const a, vec##n const b) \ 27{ \ 28 int i; \ 29 for(i=0; i<n; ++i) \ 30 r[i] = a[i] - b[i]; \ 31} \ 32LINMATH_H_FUNC void vec##n##_scale(vec##n r, vec##n const v, float const s) \ 33{ \ 34 int i; \ 35 for(i=0; i<n; ++i) \ 36 r[i] = v[i] * s; \ 37} \ 38LINMATH_H_FUNC float vec##n##_mul_inner(vec##n const a, vec##n const b) \ 39{ \ 40 float p = 0.f; \ 41 int i; \ 42 for(i=0; i<n; ++i) \ 43 p += b[i]*a[i]; \ 44 return p; \ 45} \ 46LINMATH_H_FUNC float vec##n##_len(vec##n const v) \ 47{ \ 48 return sqrtf(vec##n##_mul_inner(v,v)); \ 49} \ 50LINMATH_H_FUNC void vec##n##_norm(vec##n r, vec##n const v) \ 51{ \ 52 float k = 1.f / vec##n##_len(v); \ 53 vec##n##_scale(r, v, k); \ 54} \ 55LINMATH_H_FUNC void vec##n##_min(vec##n r, vec##n const a, vec##n const b) \ 56{ \ 57 int i; \ 58 for(i=0; i<n; ++i) \ 59 r[i] = a[i]<b[i] ? a[i] : b[i]; \ 60} \ 61LINMATH_H_FUNC void vec##n##_max(vec##n r, vec##n const a, vec##n const b) \ 62{ \ 63 int i; \ 64 for(i=0; i<n; ++i) \ 65 r[i] = a[i]>b[i] ? a[i] : b[i]; \ 66} \ 67LINMATH_H_FUNC void vec##n##_dup(vec##n r, vec##n const src) \ 68{ \ 69 int i; \ 70 for(i=0; i<n; ++i) \ 71 r[i] = src[i]; \ 72} 73 74LINMATH_H_DEFINE_VEC(2) 75LINMATH_H_DEFINE_VEC(3) 76LINMATH_H_DEFINE_VEC(4) 77 78LINMATH_H_FUNC void vec3_mul_cross(vec3 r, vec3 const a, vec3 const b) 79{ 80 r[0] = a[1]*b[2] - a[2]*b[1]; 81 r[1] = a[2]*b[0] - a[0]*b[2]; 82 r[2] = a[0]*b[1] - a[1]*b[0]; 83} 84 85LINMATH_H_FUNC void vec3_reflect(vec3 r, vec3 const v, vec3 const n) 86{ 87 float p = 2.f * vec3_mul_inner(v, n); 88 int i; 89 for(i=0;i<3;++i) 90 r[i] = v[i] - p*n[i]; 91} 92 93LINMATH_H_FUNC void vec4_mul_cross(vec4 r, vec4 const a, vec4 const b) 94{ 95 r[0] = a[1]*b[2] - a[2]*b[1]; 96 r[1] = a[2]*b[0] - a[0]*b[2]; 97 r[2] = a[0]*b[1] - a[1]*b[0]; 98 r[3] = 1.f; 99} 100 101LINMATH_H_FUNC void vec4_reflect(vec4 r, vec4 const v, vec4 const n) 102{ 103 float p = 2.f*vec4_mul_inner(v, n); 104 int i; 105 for(i=0;i<4;++i) 106 r[i] = v[i] - p*n[i]; 107} 108 109typedef vec4 mat4x4[4]; 110LINMATH_H_FUNC void mat4x4_identity(mat4x4 M) 111{ 112 int i, j; 113 for(i=0; i<4; ++i) 114 for(j=0; j<4; ++j) 115 M[i][j] = i==j ? 1.f : 0.f; 116} 117LINMATH_H_FUNC void mat4x4_dup(mat4x4 M, mat4x4 const N) 118{ 119 int i; 120 for(i=0; i<4; ++i) 121 vec4_dup(M[i], N[i]); 122} 123LINMATH_H_FUNC void mat4x4_row(vec4 r, mat4x4 const M, int i) 124{ 125 int k; 126 for(k=0; k<4; ++k) 127 r[k] = M[k][i]; 128} 129LINMATH_H_FUNC void mat4x4_col(vec4 r, mat4x4 const M, int i) 130{ 131 int k; 132 for(k=0; k<4; ++k) 133 r[k] = M[i][k]; 134} 135LINMATH_H_FUNC void mat4x4_transpose(mat4x4 M, mat4x4 const N) 136{ 137 // Note: if M and N are the same, the user has to 138 // explicitly make a copy of M and set it to N. 139 int i, j; 140 for(j=0; j<4; ++j) 141 for(i=0; i<4; ++i) 142 M[i][j] = N[j][i]; 143} 144LINMATH_H_FUNC void mat4x4_add(mat4x4 M, mat4x4 const a, mat4x4 const b) 145{ 146 int i; 147 for(i=0; i<4; ++i) 148 vec4_add(M[i], a[i], b[i]); 149} 150LINMATH_H_FUNC void mat4x4_sub(mat4x4 M, mat4x4 const a, mat4x4 const b) 151{ 152 int i; 153 for(i=0; i<4; ++i) 154 vec4_sub(M[i], a[i], b[i]); 155} 156LINMATH_H_FUNC void mat4x4_scale(mat4x4 M, mat4x4 const a, float k) 157{ 158 int i; 159 for(i=0; i<4; ++i) 160 vec4_scale(M[i], a[i], k); 161} 162LINMATH_H_FUNC void mat4x4_scale_aniso(mat4x4 M, mat4x4 const a, float x, float y, float z) 163{ 164 vec4_scale(M[0], a[0], x); 165 vec4_scale(M[1], a[1], y); 166 vec4_scale(M[2], a[2], z); 167 vec4_dup(M[3], a[3]); 168} 169LINMATH_H_FUNC void mat4x4_mul(mat4x4 M, mat4x4 const a, mat4x4 const b) 170{ 171 mat4x4 temp; 172 int k, r, c; 173 for(c=0; c<4; ++c) for(r=0; r<4; ++r) { 174 temp[c][r] = 0.f; 175 for(k=0; k<4; ++k) 176 temp[c][r] += a[k][r] * b[c][k]; 177 } 178 mat4x4_dup(M, temp); 179} 180LINMATH_H_FUNC void mat4x4_mul_vec4(vec4 r, mat4x4 const M, vec4 const v) 181{ 182 int i, j; 183 for(j=0; j<4; ++j) { 184 r[j] = 0.f; 185 for(i=0; i<4; ++i) 186 r[j] += M[i][j] * v[i]; 187 } 188} 189LINMATH_H_FUNC void mat4x4_translate(mat4x4 T, float x, float y, float z) 190{ 191 mat4x4_identity(T); 192 T[3][0] = x; 193 T[3][1] = y; 194 T[3][2] = z; 195} 196LINMATH_H_FUNC void mat4x4_translate_in_place(mat4x4 M, float x, float y, float z) 197{ 198 vec4 t = {x, y, z, 0}; 199 vec4 r; 200 int i; 201 for (i = 0; i < 4; ++i) { 202 mat4x4_row(r, M, i); 203 M[3][i] += vec4_mul_inner(r, t); 204 } 205} 206LINMATH_H_FUNC void mat4x4_from_vec3_mul_outer(mat4x4 M, vec3 const a, vec3 const b) 207{ 208 int i, j; 209 for(i=0; i<4; ++i) for(j=0; j<4; ++j) 210 M[i][j] = i<3 && j<3 ? a[i] * b[j] : 0.f; 211} 212LINMATH_H_FUNC void mat4x4_rotate(mat4x4 R, mat4x4 const M, float x, float y, float z, float angle) 213{ 214 float s = sinf(angle); 215 float c = cosf(angle); 216 vec3 u = {x, y, z}; 217 218 if(vec3_len(u) > 1e-4) { 219 vec3_norm(u, u); 220 mat4x4 T; 221 mat4x4_from_vec3_mul_outer(T, u, u); 222 223 mat4x4 S = { 224 { 0, u[2], -u[1], 0}, 225 {-u[2], 0, u[0], 0}, 226 { u[1], -u[0], 0, 0}, 227 { 0, 0, 0, 0} 228 }; 229 mat4x4_scale(S, S, s); 230 231 mat4x4 C; 232 mat4x4_identity(C); 233 mat4x4_sub(C, C, T); 234 235 mat4x4_scale(C, C, c); 236 237 mat4x4_add(T, T, C); 238 mat4x4_add(T, T, S); 239 240 T[3][3] = 1.f; 241 mat4x4_mul(R, M, T); 242 } else { 243 mat4x4_dup(R, M); 244 } 245} 246LINMATH_H_FUNC void mat4x4_rotate_X(mat4x4 Q, mat4x4 const M, float angle) 247{ 248 float s = sinf(angle); 249 float c = cosf(angle); 250 mat4x4 R = { 251 {1.f, 0.f, 0.f, 0.f}, 252 {0.f, c, s, 0.f}, 253 {0.f, -s, c, 0.f}, 254 {0.f, 0.f, 0.f, 1.f} 255 }; 256 mat4x4_mul(Q, M, R); 257} 258LINMATH_H_FUNC void mat4x4_rotate_Y(mat4x4 Q, mat4x4 const M, float angle) 259{ 260 float s = sinf(angle); 261 float c = cosf(angle); 262 mat4x4 R = { 263 { c, 0.f, -s, 0.f}, 264 { 0.f, 1.f, 0.f, 0.f}, 265 { s, 0.f, c, 0.f}, 266 { 0.f, 0.f, 0.f, 1.f} 267 }; 268 mat4x4_mul(Q, M, R); 269} 270LINMATH_H_FUNC void mat4x4_rotate_Z(mat4x4 Q, mat4x4 const M, float angle) 271{ 272 float s = sinf(angle); 273 float c = cosf(angle); 274 mat4x4 R = { 275 { c, s, 0.f, 0.f}, 276 { -s, c, 0.f, 0.f}, 277 { 0.f, 0.f, 1.f, 0.f}, 278 { 0.f, 0.f, 0.f, 1.f} 279 }; 280 mat4x4_mul(Q, M, R); 281} 282LINMATH_H_FUNC void mat4x4_invert(mat4x4 T, mat4x4 const M) 283{ 284 float s[6]; 285 float c[6]; 286 s[0] = M[0][0]*M[1][1] - M[1][0]*M[0][1]; 287 s[1] = M[0][0]*M[1][2] - M[1][0]*M[0][2]; 288 s[2] = M[0][0]*M[1][3] - M[1][0]*M[0][3]; 289 s[3] = M[0][1]*M[1][2] - M[1][1]*M[0][2]; 290 s[4] = M[0][1]*M[1][3] - M[1][1]*M[0][3]; 291 s[5] = M[0][2]*M[1][3] - M[1][2]*M[0][3]; 292 293 c[0] = M[2][0]*M[3][1] - M[3][0]*M[2][1]; 294 c[1] = M[2][0]*M[3][2] - M[3][0]*M[2][2]; 295 c[2] = M[2][0]*M[3][3] - M[3][0]*M[2][3]; 296 c[3] = M[2][1]*M[3][2] - M[3][1]*M[2][2]; 297 c[4] = M[2][1]*M[3][3] - M[3][1]*M[2][3]; 298 c[5] = M[2][2]*M[3][3] - M[3][2]*M[2][3]; 299 300 /* Assumes it is invertible */ 301 float idet = 1.0f/( s[0]*c[5]-s[1]*c[4]+s[2]*c[3]+s[3]*c[2]-s[4]*c[1]+s[5]*c[0] ); 302 303 T[0][0] = ( M[1][1] * c[5] - M[1][2] * c[4] + M[1][3] * c[3]) * idet; 304 T[0][1] = (-M[0][1] * c[5] + M[0][2] * c[4] - M[0][3] * c[3]) * idet; 305 T[0][2] = ( M[3][1] * s[5] - M[3][2] * s[4] + M[3][3] * s[3]) * idet; 306 T[0][3] = (-M[2][1] * s[5] + M[2][2] * s[4] - M[2][3] * s[3]) * idet; 307 308 T[1][0] = (-M[1][0] * c[5] + M[1][2] * c[2] - M[1][3] * c[1]) * idet; 309 T[1][1] = ( M[0][0] * c[5] - M[0][2] * c[2] + M[0][3] * c[1]) * idet; 310 T[1][2] = (-M[3][0] * s[5] + M[3][2] * s[2] - M[3][3] * s[1]) * idet; 311 T[1][3] = ( M[2][0] * s[5] - M[2][2] * s[2] + M[2][3] * s[1]) * idet; 312 313 T[2][0] = ( M[1][0] * c[4] - M[1][1] * c[2] + M[1][3] * c[0]) * idet; 314 T[2][1] = (-M[0][0] * c[4] + M[0][1] * c[2] - M[0][3] * c[0]) * idet; 315 T[2][2] = ( M[3][0] * s[4] - M[3][1] * s[2] + M[3][3] * s[0]) * idet; 316 T[2][3] = (-M[2][0] * s[4] + M[2][1] * s[2] - M[2][3] * s[0]) * idet; 317 318 T[3][0] = (-M[1][0] * c[3] + M[1][1] * c[1] - M[1][2] * c[0]) * idet; 319 T[3][1] = ( M[0][0] * c[3] - M[0][1] * c[1] + M[0][2] * c[0]) * idet; 320 T[3][2] = (-M[3][0] * s[3] + M[3][1] * s[1] - M[3][2] * s[0]) * idet; 321 T[3][3] = ( M[2][0] * s[3] - M[2][1] * s[1] + M[2][2] * s[0]) * idet; 322} 323LINMATH_H_FUNC void mat4x4_orthonormalize(mat4x4 R, mat4x4 const M) 324{ 325 mat4x4_dup(R, M); 326 float s = 1.f; 327 vec3 h; 328 329 vec3_norm(R[2], R[2]); 330 331 s = vec3_mul_inner(R[1], R[2]); 332 vec3_scale(h, R[2], s); 333 vec3_sub(R[1], R[1], h); 334 vec3_norm(R[1], R[1]); 335 336 s = vec3_mul_inner(R[0], R[2]); 337 vec3_scale(h, R[2], s); 338 vec3_sub(R[0], R[0], h); 339 340 s = vec3_mul_inner(R[0], R[1]); 341 vec3_scale(h, R[1], s); 342 vec3_sub(R[0], R[0], h); 343 vec3_norm(R[0], R[0]); 344} 345 346LINMATH_H_FUNC void mat4x4_frustum(mat4x4 M, float l, float r, float b, float t, float n, float f) 347{ 348 M[0][0] = 2.f*n/(r-l); 349 M[0][1] = M[0][2] = M[0][3] = 0.f; 350 351 M[1][1] = 2.f*n/(t-b); 352 M[1][0] = M[1][2] = M[1][3] = 0.f; 353 354 M[2][0] = (r+l)/(r-l); 355 M[2][1] = (t+b)/(t-b); 356 M[2][2] = -(f+n)/(f-n); 357 M[2][3] = -1.f; 358 359 M[3][2] = -2.f*(f*n)/(f-n); 360 M[3][0] = M[3][1] = M[3][3] = 0.f; 361} 362LINMATH_H_FUNC void mat4x4_ortho(mat4x4 M, float l, float r, float b, float t, float n, float f) 363{ 364 M[0][0] = 2.f/(r-l); 365 M[0][1] = M[0][2] = M[0][3] = 0.f; 366 367 M[1][1] = 2.f/(t-b); 368 M[1][0] = M[1][2] = M[1][3] = 0.f; 369 370 M[2][2] = -2.f/(f-n); 371 M[2][0] = M[2][1] = M[2][3] = 0.f; 372 373 M[3][0] = -(r+l)/(r-l); 374 M[3][1] = -(t+b)/(t-b); 375 M[3][2] = -(f+n)/(f-n); 376 M[3][3] = 1.f; 377} 378LINMATH_H_FUNC void mat4x4_perspective(mat4x4 m, float y_fov, float aspect, float n, float f) 379{ 380 /* NOTE: Degrees are an unhandy unit to work with. 381 * linmath.h uses radians for everything! */ 382 float const a = 1.f / tanf(y_fov / 2.f); 383 384 m[0][0] = a / aspect; 385 m[0][1] = 0.f; 386 m[0][2] = 0.f; 387 m[0][3] = 0.f; 388 389 m[1][0] = 0.f; 390 m[1][1] = a; 391 m[1][2] = 0.f; 392 m[1][3] = 0.f; 393 394 m[2][0] = 0.f; 395 m[2][1] = 0.f; 396 m[2][2] = -((f + n) / (f - n)); 397 m[2][3] = -1.f; 398 399 m[3][0] = 0.f; 400 m[3][1] = 0.f; 401 m[3][2] = -((2.f * f * n) / (f - n)); 402 m[3][3] = 0.f; 403} 404LINMATH_H_FUNC void mat4x4_look_at(mat4x4 m, vec3 const eye, vec3 const center, vec3 const up) 405{ 406 /* Adapted from Android's OpenGL Matrix.java. */ 407 /* See the OpenGL GLUT documentation for gluLookAt for a description */ 408 /* of the algorithm. We implement it in a straightforward way: */ 409 410 /* TODO: The negation of of can be spared by swapping the order of 411 * operands in the following cross products in the right way. */ 412 vec3 f; 413 vec3_sub(f, center, eye); 414 vec3_norm(f, f); 415 416 vec3 s; 417 vec3_mul_cross(s, f, up); 418 vec3_norm(s, s); 419 420 vec3 t; 421 vec3_mul_cross(t, s, f); 422 423 m[0][0] = s[0]; 424 m[0][1] = t[0]; 425 m[0][2] = -f[0]; 426 m[0][3] = 0.f; 427 428 m[1][0] = s[1]; 429 m[1][1] = t[1]; 430 m[1][2] = -f[1]; 431 m[1][3] = 0.f; 432 433 m[2][0] = s[2]; 434 m[2][1] = t[2]; 435 m[2][2] = -f[2]; 436 m[2][3] = 0.f; 437 438 m[3][0] = 0.f; 439 m[3][1] = 0.f; 440 m[3][2] = 0.f; 441 m[3][3] = 1.f; 442 443 mat4x4_translate_in_place(m, -eye[0], -eye[1], -eye[2]); 444} 445 446typedef float quat[4]; 447#define quat_add vec4_add 448#define quat_sub vec4_sub 449#define quat_norm vec4_norm 450#define quat_scale vec4_scale 451#define quat_mul_inner vec4_mul_inner 452 453LINMATH_H_FUNC void quat_identity(quat q) 454{ 455 q[0] = q[1] = q[2] = 0.f; 456 q[3] = 1.f; 457} 458LINMATH_H_FUNC void quat_mul(quat r, quat const p, quat const q) 459{ 460 vec3 w; 461 vec3_mul_cross(r, p, q); 462 vec3_scale(w, p, q[3]); 463 vec3_add(r, r, w); 464 vec3_scale(w, q, p[3]); 465 vec3_add(r, r, w); 466 r[3] = p[3]*q[3] - vec3_mul_inner(p, q); 467} 468LINMATH_H_FUNC void quat_conj(quat r, quat const q) 469{ 470 int i; 471 for(i=0; i<3; ++i) 472 r[i] = -q[i]; 473 r[3] = q[3]; 474} 475LINMATH_H_FUNC void quat_rotate(quat r, float angle, vec3 const axis) { 476 vec3 axis_norm; 477 vec3_norm(axis_norm, axis); 478 float s = sinf(angle / 2); 479 float c = cosf(angle / 2); 480 vec3_scale(r, axis_norm, s); 481 r[3] = c; 482} 483LINMATH_H_FUNC void quat_mul_vec3(vec3 r, quat const q, vec3 const v) 484{ 485/* 486 * Method by Fabian 'ryg' Giessen (of Farbrausch) 487t = 2 * cross(q.xyz, v) 488v' = v + q.w * t + cross(q.xyz, t) 489 */ 490 vec3 t; 491 vec3 q_xyz = {q[0], q[1], q[2]}; 492 vec3 u = {q[0], q[1], q[2]}; 493 494 vec3_mul_cross(t, q_xyz, v); 495 vec3_scale(t, t, 2); 496 497 vec3_mul_cross(u, q_xyz, t); 498 vec3_scale(t, t, q[3]); 499 500 vec3_add(r, v, t); 501 vec3_add(r, r, u); 502} 503LINMATH_H_FUNC void mat4x4_from_quat(mat4x4 M, quat const q) 504{ 505 float a = q[3]; 506 float b = q[0]; 507 float c = q[1]; 508 float d = q[2]; 509 float a2 = a*a; 510 float b2 = b*b; 511 float c2 = c*c; 512 float d2 = d*d; 513 514 M[0][0] = a2 + b2 - c2 - d2; 515 M[0][1] = 2.f*(b*c + a*d); 516 M[0][2] = 2.f*(b*d - a*c); 517 M[0][3] = 0.f; 518 519 M[1][0] = 2*(b*c - a*d); 520 M[1][1] = a2 - b2 + c2 - d2; 521 M[1][2] = 2.f*(c*d + a*b); 522 M[1][3] = 0.f; 523 524 M[2][0] = 2.f*(b*d + a*c); 525 M[2][1] = 2.f*(c*d - a*b); 526 M[2][2] = a2 - b2 - c2 + d2; 527 M[2][3] = 0.f; 528 529 M[3][0] = M[3][1] = M[3][2] = 0.f; 530 M[3][3] = 1.f; 531} 532 533LINMATH_H_FUNC void mat4x4o_mul_quat(mat4x4 R, mat4x4 const M, quat const q) 534{ 535/* XXX: The way this is written only works for orthogonal matrices. */ 536/* TODO: Take care of non-orthogonal case. */ 537 quat_mul_vec3(R[0], q, M[0]); 538 quat_mul_vec3(R[1], q, M[1]); 539 quat_mul_vec3(R[2], q, M[2]); 540 541 R[3][0] = R[3][1] = R[3][2] = 0.f; 542 R[0][3] = M[0][3]; 543 R[1][3] = M[1][3]; 544 R[2][3] = M[2][3]; 545 R[3][3] = M[3][3]; // typically 1.0, but here we make it general 546} 547LINMATH_H_FUNC void quat_from_mat4x4(quat q, mat4x4 const M) 548{ 549 float r=0.f; 550 int i; 551 552 int perm[] = { 0, 1, 2, 0, 1 }; 553 int *p = perm; 554 555 for(i = 0; i<3; i++) { 556 float m = M[i][i]; 557 if( m < r ) 558 continue; 559 m = r; 560 p = &perm[i]; 561 } 562 563 r = sqrtf(1.f + M[p[0]][p[0]] - M[p[1]][p[1]] - M[p[2]][p[2]] ); 564 565 if(r < 1e-6) { 566 q[0] = 1.f; 567 q[1] = q[2] = q[3] = 0.f; 568 return; 569 } 570 571 q[0] = r/2.f; 572 q[1] = (M[p[0]][p[1]] - M[p[1]][p[0]])/(2.f*r); 573 q[2] = (M[p[2]][p[0]] - M[p[0]][p[2]])/(2.f*r); 574 q[3] = (M[p[2]][p[1]] - M[p[1]][p[2]])/(2.f*r); 575} 576 577LINMATH_H_FUNC void mat4x4_arcball(mat4x4 R, mat4x4 const M, vec2 const _a, vec2 const _b, float s) 578{ 579 vec2 a; memcpy(a, _a, sizeof(a)); 580 vec2 b; memcpy(b, _b, sizeof(b)); 581 582 float z_a = 0.f; 583 float z_b = 0.f; 584 585 if(vec2_len(a) < 1.f) { 586 z_a = sqrtf(1.f - vec2_mul_inner(a, a)); 587 } else { 588 vec2_norm(a, a); 589 } 590 591 if(vec2_len(b) < 1.f) { 592 z_b = sqrtf(1.f - vec2_mul_inner(b, b)); 593 } else { 594 vec2_norm(b, b); 595 } 596 597 vec3 a_ = {a[0], a[1], z_a}; 598 vec3 b_ = {b[0], b[1], z_b}; 599 600 vec3 c_; 601 vec3_mul_cross(c_, a_, b_); 602 603 float const angle = acos(vec3_mul_inner(a_, b_)) * s; 604 mat4x4_rotate(R, M, c_[0], c_[1], c_[2], angle); 605} 606#endif 607[FILE END](C) 2025 0x4248 (C) 2025 4248 Media and 4248 Systems, All part of 0x4248 See LICENCE files for more information. 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