1 | // SHAPES :: https://github.com/prideout/par |
2 | // Simple C library for creation and manipulation of triangle meshes. |
3 | // |
4 | // The API is divided into three sections: |
5 | // |
6 | // - Generators. Create parametric surfaces, platonic solids, etc. |
7 | // - Queries. Ask a mesh for its axis-aligned bounding box, etc. |
8 | // - Transforms. Rotate a mesh, merge it with another, add normals, etc. |
9 | // |
10 | // In addition to the comment block above each function declaration, the API |
11 | // has informal documentation here: |
12 | // |
13 | // https://prideout.net/shapes |
14 | // |
15 | // For our purposes, a "mesh" is a list of points and a list of triangles; the |
16 | // former is a flattened list of three-tuples (32-bit floats) and the latter is |
17 | // also a flattened list of three-tuples (16-bit uints). Triangles are always |
18 | // oriented such that their front face winds counter-clockwise. |
19 | // |
20 | // Optionally, meshes can contain 3D normals (one per vertex), and 2D texture |
21 | // coordinates (one per vertex). That's it! If you need something fancier, |
22 | // look elsewhere. |
23 | // |
24 | // The MIT License |
25 | // Copyright (c) 2015 Philip Rideout |
26 | |
27 | #ifndef PAR_SHAPES_H |
28 | #define PAR_SHAPES_H |
29 | |
30 | #ifdef __cplusplus |
31 | extern "C" { |
32 | #endif |
33 | |
34 | #include <stdint.h> |
35 | |
36 | // Ray: commented to avoid conflict with raylib bool |
37 | /* |
38 | #if !defined(_MSC_VER) |
39 | # include <stdbool.h> |
40 | #else // MSVC |
41 | # if _MSC_VER >= 1800 |
42 | # include <stdbool.h> |
43 | # else // stdbool.h missing prior to MSVC++ 12.0 (VS2013) |
44 | //# define bool int |
45 | //# define true 1 |
46 | //# define false 0 |
47 | # endif |
48 | #endif |
49 | */ |
50 | |
51 | #ifndef PAR_SHAPES_T |
52 | #define PAR_SHAPES_T uint16_t |
53 | #endif |
54 | |
55 | typedef struct par_shapes_mesh_s { |
56 | float* points; // Flat list of 3-tuples (X Y Z X Y Z...) |
57 | int npoints; // Number of points |
58 | PAR_SHAPES_T* triangles; // Flat list of 3-tuples (I J K I J K...) |
59 | int ntriangles; // Number of triangles |
60 | float* normals; // Optional list of 3-tuples (X Y Z X Y Z...) |
61 | float* tcoords; // Optional list of 2-tuples (U V U V U V...) |
62 | } par_shapes_mesh; |
63 | |
64 | void par_shapes_free_mesh(par_shapes_mesh*); |
65 | |
66 | // Generators ------------------------------------------------------------------ |
67 | |
68 | // Instance a cylinder that sits on the Z=0 plane using the given tessellation |
69 | // levels across the UV domain. Think of "slices" like a number of pizza |
70 | // slices, and "stacks" like a number of stacked rings. Height and radius are |
71 | // both 1.0, but they can easily be changed with par_shapes_scale. |
72 | par_shapes_mesh* par_shapes_create_cylinder(int slices, int stacks); |
73 | |
74 | // Create a donut that sits on the Z=0 plane with the specified inner radius. |
75 | // The outer radius can be controlled with par_shapes_scale. |
76 | par_shapes_mesh* par_shapes_create_torus(int slices, int stacks, float radius); |
77 | |
78 | // Create a sphere with texture coordinates and small triangles near the poles. |
79 | par_shapes_mesh* par_shapes_create_parametric_sphere(int slices, int stacks); |
80 | |
81 | // Approximate a sphere with a subdivided icosahedron, which produces a nice |
82 | // distribution of triangles, but no texture coordinates. Each subdivision |
83 | // level scales the number of triangles by four, so use a very low number. |
84 | par_shapes_mesh* par_shapes_create_subdivided_sphere(int nsubdivisions); |
85 | |
86 | // More parametric surfaces. |
87 | par_shapes_mesh* par_shapes_create_klein_bottle(int slices, int stacks); |
88 | par_shapes_mesh* par_shapes_create_trefoil_knot(int slices, int stacks, |
89 | float radius); |
90 | par_shapes_mesh* par_shapes_create_hemisphere(int slices, int stacks); |
91 | par_shapes_mesh* par_shapes_create_plane(int slices, int stacks); |
92 | |
93 | // Create a parametric surface from a callback function that consumes a 2D |
94 | // point in [0,1] and produces a 3D point. |
95 | typedef void (*par_shapes_fn)(float const*, float*, void*); |
96 | par_shapes_mesh* par_shapes_create_parametric(par_shapes_fn, int slices, |
97 | int stacks, void* userdata); |
98 | |
99 | // Generate points for a 20-sided polyhedron that fits in the unit sphere. |
100 | // Texture coordinates and normals are not generated. |
101 | par_shapes_mesh* par_shapes_create_icosahedron(); |
102 | |
103 | // Generate points for a 12-sided polyhedron that fits in the unit sphere. |
104 | // Again, texture coordinates and normals are not generated. |
105 | par_shapes_mesh* par_shapes_create_dodecahedron(); |
106 | |
107 | // More platonic solids. |
108 | par_shapes_mesh* par_shapes_create_octahedron(); |
109 | par_shapes_mesh* par_shapes_create_tetrahedron(); |
110 | par_shapes_mesh* par_shapes_create_cube(); |
111 | |
112 | // Generate an orientable disk shape in 3-space. Does not include normals or |
113 | // texture coordinates. |
114 | par_shapes_mesh* par_shapes_create_disk(float radius, int slices, |
115 | float const* center, float const* normal); |
116 | |
117 | // Create an empty shape. Useful for building scenes with merge_and_free. |
118 | par_shapes_mesh* par_shapes_create_empty(); |
119 | |
120 | // Generate a rock shape that sits on the Y=0 plane, and sinks into it a bit. |
121 | // This includes smooth normals but no texture coordinates. Each subdivision |
122 | // level scales the number of triangles by four, so use a very low number. |
123 | par_shapes_mesh* par_shapes_create_rock(int seed, int nsubdivisions); |
124 | |
125 | // Create trees or vegetation by executing a recursive turtle graphics program. |
126 | // The program is a list of command-argument pairs. See the unit test for |
127 | // an example. Texture coordinates and normals are not generated. |
128 | par_shapes_mesh* par_shapes_create_lsystem(char const* program, int slices, |
129 | int maxdepth); |
130 | |
131 | // Queries --------------------------------------------------------------------- |
132 | |
133 | // Dump out a text file conforming to the venerable OBJ format. |
134 | void par_shapes_export(par_shapes_mesh const*, char const* objfile); |
135 | |
136 | // Take a pointer to 6 floats and set them to min xyz, max xyz. |
137 | void par_shapes_compute_aabb(par_shapes_mesh const* mesh, float* aabb); |
138 | |
139 | // Make a deep copy of a mesh. To make a brand new copy, pass null to "target". |
140 | // To avoid memory churn, pass an existing mesh to "target". |
141 | par_shapes_mesh* par_shapes_clone(par_shapes_mesh const* mesh, |
142 | par_shapes_mesh* target); |
143 | |
144 | // Transformations ------------------------------------------------------------- |
145 | |
146 | void par_shapes_merge(par_shapes_mesh* dst, par_shapes_mesh const* src); |
147 | void par_shapes_translate(par_shapes_mesh*, float x, float y, float z); |
148 | void par_shapes_rotate(par_shapes_mesh*, float radians, float const* axis); |
149 | void par_shapes_scale(par_shapes_mesh*, float x, float y, float z); |
150 | void par_shapes_merge_and_free(par_shapes_mesh* dst, par_shapes_mesh* src); |
151 | |
152 | // Reverse the winding of a run of faces. Useful when drawing the inside of |
153 | // a Cornell Box. Pass 0 for nfaces to reverse every face in the mesh. |
154 | void par_shapes_invert(par_shapes_mesh*, int startface, int nfaces); |
155 | |
156 | // Remove all triangles whose area is less than minarea. |
157 | void par_shapes_remove_degenerate(par_shapes_mesh*, float minarea); |
158 | |
159 | // Dereference the entire index buffer and replace the point list. |
160 | // This creates an inefficient structure, but is useful for drawing facets. |
161 | // If create_indices is true, a trivial "0 1 2 3..." index buffer is generated. |
162 | void par_shapes_unweld(par_shapes_mesh* mesh, bool create_indices); |
163 | |
164 | // Merge colocated verts, build a new index buffer, and return the |
165 | // optimized mesh. Epsilon is the maximum distance to consider when |
166 | // welding vertices. The mapping argument can be null, or a pointer to |
167 | // npoints integers, which gets filled with the mapping from old vertex |
168 | // indices to new indices. |
169 | par_shapes_mesh* par_shapes_weld(par_shapes_mesh const*, float epsilon, |
170 | PAR_SHAPES_T* mapping); |
171 | |
172 | // Compute smooth normals by averaging adjacent facet normals. |
173 | void par_shapes_compute_normals(par_shapes_mesh* m); |
174 | |
175 | #ifndef PAR_PI |
176 | #define PAR_PI (3.14159265359) |
177 | #define PAR_MIN(a, b) (a > b ? b : a) |
178 | #define PAR_MAX(a, b) (a > b ? a : b) |
179 | #define PAR_CLAMP(v, lo, hi) PAR_MAX(lo, PAR_MIN(hi, v)) |
180 | #define PAR_SWAP(T, A, B) { T tmp = B; B = A; A = tmp; } |
181 | #define PAR_SQR(a) ((a) * (a)) |
182 | #endif |
183 | |
184 | #ifndef PAR_MALLOC |
185 | #define PAR_MALLOC(T, N) ((T*) malloc(N * sizeof(T))) |
186 | #define PAR_CALLOC(T, N) ((T*) calloc(N * sizeof(T), 1)) |
187 | #define PAR_REALLOC(T, BUF, N) ((T*) realloc(BUF, sizeof(T) * (N))) |
188 | #define PAR_FREE(BUF) free(BUF) |
189 | #endif |
190 | |
191 | #ifdef __cplusplus |
192 | } |
193 | #endif |
194 | |
195 | // ----------------------------------------------------------------------------- |
196 | // END PUBLIC API |
197 | // ----------------------------------------------------------------------------- |
198 | |
199 | #ifdef PAR_SHAPES_IMPLEMENTATION |
200 | #include <stdlib.h> |
201 | #include <stdio.h> |
202 | #include <assert.h> |
203 | #include <float.h> |
204 | #include <string.h> |
205 | #include <math.h> |
206 | #include <errno.h> |
207 | |
208 | static void par_shapes__sphere(float const* uv, float* xyz, void*); |
209 | static void par_shapes__hemisphere(float const* uv, float* xyz, void*); |
210 | static void par_shapes__plane(float const* uv, float* xyz, void*); |
211 | static void par_shapes__klein(float const* uv, float* xyz, void*); |
212 | static void par_shapes__cylinder(float const* uv, float* xyz, void*); |
213 | static void par_shapes__torus(float const* uv, float* xyz, void*); |
214 | static void par_shapes__trefoil(float const* uv, float* xyz, void*); |
215 | |
216 | struct osn_context; |
217 | static int par__simplex_noise(int64_t seed, struct osn_context** ctx); |
218 | static void par__simplex_noise_free(struct osn_context* ctx); |
219 | static double par__simplex_noise2(struct osn_context* ctx, double x, double y); |
220 | |
221 | static void par_shapes__copy3(float* result, float const* a) |
222 | { |
223 | result[0] = a[0]; |
224 | result[1] = a[1]; |
225 | result[2] = a[2]; |
226 | } |
227 | |
228 | static float par_shapes__dot3(float const* a, float const* b) |
229 | { |
230 | return b[0] * a[0] + b[1] * a[1] + b[2] * a[2]; |
231 | } |
232 | |
233 | static void par_shapes__transform3(float* p, float const* x, float const* y, |
234 | float const* z) |
235 | { |
236 | float px = par_shapes__dot3(p, x); |
237 | float py = par_shapes__dot3(p, y); |
238 | float pz = par_shapes__dot3(p, z); |
239 | p[0] = px; |
240 | p[1] = py; |
241 | p[2] = pz; |
242 | } |
243 | |
244 | static void par_shapes__cross3(float* result, float const* a, float const* b) |
245 | { |
246 | float x = (a[1] * b[2]) - (a[2] * b[1]); |
247 | float y = (a[2] * b[0]) - (a[0] * b[2]); |
248 | float z = (a[0] * b[1]) - (a[1] * b[0]); |
249 | result[0] = x; |
250 | result[1] = y; |
251 | result[2] = z; |
252 | } |
253 | |
254 | static void par_shapes__mix3(float* d, float const* a, float const* b, float t) |
255 | { |
256 | float x = b[0] * t + a[0] * (1 - t); |
257 | float y = b[1] * t + a[1] * (1 - t); |
258 | float z = b[2] * t + a[2] * (1 - t); |
259 | d[0] = x; |
260 | d[1] = y; |
261 | d[2] = z; |
262 | } |
263 | |
264 | static void par_shapes__scale3(float* result, float a) |
265 | { |
266 | result[0] *= a; |
267 | result[1] *= a; |
268 | result[2] *= a; |
269 | } |
270 | |
271 | static void par_shapes__normalize3(float* v) |
272 | { |
273 | float lsqr = sqrt(v[0]*v[0] + v[1]*v[1] + v[2]*v[2]); |
274 | if (lsqr > 0) { |
275 | par_shapes__scale3(v, 1.0f / lsqr); |
276 | } |
277 | } |
278 | |
279 | static void par_shapes__subtract3(float* result, float const* a) |
280 | { |
281 | result[0] -= a[0]; |
282 | result[1] -= a[1]; |
283 | result[2] -= a[2]; |
284 | } |
285 | |
286 | static void par_shapes__add3(float* result, float const* a) |
287 | { |
288 | result[0] += a[0]; |
289 | result[1] += a[1]; |
290 | result[2] += a[2]; |
291 | } |
292 | |
293 | static float par_shapes__sqrdist3(float const* a, float const* b) |
294 | { |
295 | float dx = a[0] - b[0]; |
296 | float dy = a[1] - b[1]; |
297 | float dz = a[2] - b[2]; |
298 | return dx * dx + dy * dy + dz * dz; |
299 | } |
300 | |
301 | static void par_shapes__compute_welded_normals(par_shapes_mesh* m) |
302 | { |
303 | m->normals = PAR_MALLOC(float, m->npoints * 3); |
304 | PAR_SHAPES_T* weldmap = PAR_MALLOC(PAR_SHAPES_T, m->npoints); |
305 | par_shapes_mesh* welded = par_shapes_weld(m, 0.01, weldmap); |
306 | par_shapes_compute_normals(welded); |
307 | float* pdst = m->normals; |
308 | for (int i = 0; i < m->npoints; i++, pdst += 3) { |
309 | int d = weldmap[i]; |
310 | float const* pnormal = welded->normals + d * 3; |
311 | pdst[0] = pnormal[0]; |
312 | pdst[1] = pnormal[1]; |
313 | pdst[2] = pnormal[2]; |
314 | } |
315 | PAR_FREE(weldmap); |
316 | par_shapes_free_mesh(welded); |
317 | } |
318 | |
319 | par_shapes_mesh* par_shapes_create_cylinder(int slices, int stacks) |
320 | { |
321 | if (slices < 3 || stacks < 1) { |
322 | return 0; |
323 | } |
324 | return par_shapes_create_parametric(par_shapes__cylinder, slices, |
325 | stacks, 0); |
326 | } |
327 | |
328 | par_shapes_mesh* par_shapes_create_parametric_sphere(int slices, int stacks) |
329 | { |
330 | if (slices < 3 || stacks < 3) { |
331 | return 0; |
332 | } |
333 | par_shapes_mesh* m = par_shapes_create_parametric(par_shapes__sphere, |
334 | slices, stacks, 0); |
335 | par_shapes_remove_degenerate(m, 0.0001); |
336 | return m; |
337 | } |
338 | |
339 | par_shapes_mesh* par_shapes_create_hemisphere(int slices, int stacks) |
340 | { |
341 | if (slices < 3 || stacks < 3) { |
342 | return 0; |
343 | } |
344 | par_shapes_mesh* m = par_shapes_create_parametric(par_shapes__hemisphere, |
345 | slices, stacks, 0); |
346 | par_shapes_remove_degenerate(m, 0.0001); |
347 | return m; |
348 | } |
349 | |
350 | par_shapes_mesh* par_shapes_create_torus(int slices, int stacks, float radius) |
351 | { |
352 | if (slices < 3 || stacks < 3) { |
353 | return 0; |
354 | } |
355 | assert(radius <= 1.0 && "Use smaller radius to avoid self-intersection." ); |
356 | assert(radius >= 0.1 && "Use larger radius to avoid self-intersection." ); |
357 | void* userdata = (void*) &radius; |
358 | return par_shapes_create_parametric(par_shapes__torus, slices, |
359 | stacks, userdata); |
360 | } |
361 | |
362 | par_shapes_mesh* par_shapes_create_klein_bottle(int slices, int stacks) |
363 | { |
364 | if (slices < 3 || stacks < 3) { |
365 | return 0; |
366 | } |
367 | par_shapes_mesh* mesh = par_shapes_create_parametric( |
368 | par_shapes__klein, slices, stacks, 0); |
369 | int face = 0; |
370 | for (int stack = 0; stack < stacks; stack++) { |
371 | for (int slice = 0; slice < slices; slice++, face += 2) { |
372 | if (stack < 27 * stacks / 32) { |
373 | par_shapes_invert(mesh, face, 2); |
374 | } |
375 | } |
376 | } |
377 | par_shapes__compute_welded_normals(mesh); |
378 | return mesh; |
379 | } |
380 | |
381 | par_shapes_mesh* par_shapes_create_trefoil_knot(int slices, int stacks, |
382 | float radius) |
383 | { |
384 | if (slices < 3 || stacks < 3) { |
385 | return 0; |
386 | } |
387 | assert(radius <= 3.0 && "Use smaller radius to avoid self-intersection." ); |
388 | assert(radius >= 0.5 && "Use larger radius to avoid self-intersection." ); |
389 | void* userdata = (void*) &radius; |
390 | return par_shapes_create_parametric(par_shapes__trefoil, slices, |
391 | stacks, userdata); |
392 | } |
393 | |
394 | par_shapes_mesh* par_shapes_create_plane(int slices, int stacks) |
395 | { |
396 | if (slices < 1 || stacks < 1) { |
397 | return 0; |
398 | } |
399 | return par_shapes_create_parametric(par_shapes__plane, slices, |
400 | stacks, 0); |
401 | } |
402 | |
403 | par_shapes_mesh* par_shapes_create_parametric(par_shapes_fn fn, |
404 | int slices, int stacks, void* userdata) |
405 | { |
406 | par_shapes_mesh* mesh = PAR_CALLOC(par_shapes_mesh, 1); |
407 | |
408 | // Generate verts. |
409 | mesh->npoints = (slices + 1) * (stacks + 1); |
410 | mesh->points = PAR_CALLOC(float, 3 * mesh->npoints); |
411 | float uv[2]; |
412 | float xyz[3]; |
413 | float* points = mesh->points; |
414 | for (int stack = 0; stack < stacks + 1; stack++) { |
415 | uv[0] = (float) stack / stacks; |
416 | for (int slice = 0; slice < slices + 1; slice++) { |
417 | uv[1] = (float) slice / slices; |
418 | fn(uv, xyz, userdata); |
419 | *points++ = xyz[0]; |
420 | *points++ = xyz[1]; |
421 | *points++ = xyz[2]; |
422 | } |
423 | } |
424 | |
425 | // Generate texture coordinates. |
426 | mesh->tcoords = PAR_CALLOC(float, 2 * mesh->npoints); |
427 | float* uvs = mesh->tcoords; |
428 | for (int stack = 0; stack < stacks + 1; stack++) { |
429 | uv[0] = (float) stack / stacks; |
430 | for (int slice = 0; slice < slices + 1; slice++) { |
431 | uv[1] = (float) slice / slices; |
432 | *uvs++ = uv[0]; |
433 | *uvs++ = uv[1]; |
434 | } |
435 | } |
436 | |
437 | // Generate faces. |
438 | mesh->ntriangles = 2 * slices * stacks; |
439 | mesh->triangles = PAR_CALLOC(PAR_SHAPES_T, 3 * mesh->ntriangles); |
440 | int v = 0; |
441 | PAR_SHAPES_T* face = mesh->triangles; |
442 | for (int stack = 0; stack < stacks; stack++) { |
443 | for (int slice = 0; slice < slices; slice++) { |
444 | int next = slice + 1; |
445 | *face++ = v + slice + slices + 1; |
446 | *face++ = v + next; |
447 | *face++ = v + slice; |
448 | *face++ = v + slice + slices + 1; |
449 | *face++ = v + next + slices + 1; |
450 | *face++ = v + next; |
451 | } |
452 | v += slices + 1; |
453 | } |
454 | |
455 | par_shapes__compute_welded_normals(mesh); |
456 | return mesh; |
457 | } |
458 | |
459 | void par_shapes_free_mesh(par_shapes_mesh* mesh) |
460 | { |
461 | PAR_FREE(mesh->points); |
462 | PAR_FREE(mesh->triangles); |
463 | PAR_FREE(mesh->normals); |
464 | PAR_FREE(mesh->tcoords); |
465 | PAR_FREE(mesh); |
466 | } |
467 | |
468 | void par_shapes_export(par_shapes_mesh const* mesh, char const* filename) |
469 | { |
470 | FILE* objfile = fopen(filename, "wt" ); |
471 | float const* points = mesh->points; |
472 | float const* tcoords = mesh->tcoords; |
473 | float const* norms = mesh->normals; |
474 | PAR_SHAPES_T const* indices = mesh->triangles; |
475 | if (tcoords && norms) { |
476 | for (int nvert = 0; nvert < mesh->npoints; nvert++) { |
477 | fprintf(objfile, "v %f %f %f\n" , points[0], points[1], points[2]); |
478 | fprintf(objfile, "vt %f %f\n" , tcoords[0], tcoords[1]); |
479 | fprintf(objfile, "vn %f %f %f\n" , norms[0], norms[1], norms[2]); |
480 | points += 3; |
481 | norms += 3; |
482 | tcoords += 2; |
483 | } |
484 | for (int nface = 0; nface < mesh->ntriangles; nface++) { |
485 | int a = 1 + *indices++; |
486 | int b = 1 + *indices++; |
487 | int c = 1 + *indices++; |
488 | fprintf(objfile, "f %d/%d/%d %d/%d/%d %d/%d/%d\n" , |
489 | a, a, a, b, b, b, c, c, c); |
490 | } |
491 | } else if (norms) { |
492 | for (int nvert = 0; nvert < mesh->npoints; nvert++) { |
493 | fprintf(objfile, "v %f %f %f\n" , points[0], points[1], points[2]); |
494 | fprintf(objfile, "vn %f %f %f\n" , norms[0], norms[1], norms[2]); |
495 | points += 3; |
496 | norms += 3; |
497 | } |
498 | for (int nface = 0; nface < mesh->ntriangles; nface++) { |
499 | int a = 1 + *indices++; |
500 | int b = 1 + *indices++; |
501 | int c = 1 + *indices++; |
502 | fprintf(objfile, "f %d//%d %d//%d %d//%d\n" , a, a, b, b, c, c); |
503 | } |
504 | } else if (tcoords) { |
505 | for (int nvert = 0; nvert < mesh->npoints; nvert++) { |
506 | fprintf(objfile, "v %f %f %f\n" , points[0], points[1], points[2]); |
507 | fprintf(objfile, "vt %f %f\n" , tcoords[0], tcoords[1]); |
508 | points += 3; |
509 | tcoords += 2; |
510 | } |
511 | for (int nface = 0; nface < mesh->ntriangles; nface++) { |
512 | int a = 1 + *indices++; |
513 | int b = 1 + *indices++; |
514 | int c = 1 + *indices++; |
515 | fprintf(objfile, "f %d/%d %d/%d %d/%d\n" , a, a, b, b, c, c); |
516 | } |
517 | } else { |
518 | for (int nvert = 0; nvert < mesh->npoints; nvert++) { |
519 | fprintf(objfile, "v %f %f %f\n" , points[0], points[1], points[2]); |
520 | points += 3; |
521 | } |
522 | for (int nface = 0; nface < mesh->ntriangles; nface++) { |
523 | int a = 1 + *indices++; |
524 | int b = 1 + *indices++; |
525 | int c = 1 + *indices++; |
526 | fprintf(objfile, "f %d %d %d\n" , a, b, c); |
527 | } |
528 | } |
529 | fclose(objfile); |
530 | } |
531 | |
532 | static void par_shapes__sphere(float const* uv, float* xyz, void* userdata) |
533 | { |
534 | float phi = uv[0] * PAR_PI; |
535 | float theta = uv[1] * 2 * PAR_PI; |
536 | xyz[0] = cosf(theta) * sinf(phi); |
537 | xyz[1] = sinf(theta) * sinf(phi); |
538 | xyz[2] = cosf(phi); |
539 | } |
540 | |
541 | static void par_shapes__hemisphere(float const* uv, float* xyz, void* userdata) |
542 | { |
543 | float phi = uv[0] * PAR_PI; |
544 | float theta = uv[1] * PAR_PI; |
545 | xyz[0] = cosf(theta) * sinf(phi); |
546 | xyz[1] = sinf(theta) * sinf(phi); |
547 | xyz[2] = cosf(phi); |
548 | } |
549 | |
550 | static void par_shapes__plane(float const* uv, float* xyz, void* userdata) |
551 | { |
552 | xyz[0] = uv[0]; |
553 | xyz[1] = uv[1]; |
554 | xyz[2] = 0; |
555 | } |
556 | |
557 | static void par_shapes__klein(float const* uv, float* xyz, void* userdata) |
558 | { |
559 | float u = uv[0] * PAR_PI; |
560 | float v = uv[1] * 2 * PAR_PI; |
561 | u = u * 2; |
562 | if (u < PAR_PI) { |
563 | xyz[0] = 3 * cosf(u) * (1 + sinf(u)) + (2 * (1 - cosf(u) / 2)) * |
564 | cosf(u) * cosf(v); |
565 | xyz[2] = -8 * sinf(u) - 2 * (1 - cosf(u) / 2) * sinf(u) * cosf(v); |
566 | } else { |
567 | xyz[0] = 3 * cosf(u) * (1 + sinf(u)) + (2 * (1 - cosf(u) / 2)) * |
568 | cosf(v + PAR_PI); |
569 | xyz[2] = -8 * sinf(u); |
570 | } |
571 | xyz[1] = -2 * (1 - cosf(u) / 2) * sinf(v); |
572 | } |
573 | |
574 | static void par_shapes__cylinder(float const* uv, float* xyz, void* userdata) |
575 | { |
576 | float theta = uv[1] * 2 * PAR_PI; |
577 | xyz[0] = sinf(theta); |
578 | xyz[1] = cosf(theta); |
579 | xyz[2] = uv[0]; |
580 | } |
581 | |
582 | static void par_shapes__torus(float const* uv, float* xyz, void* userdata) |
583 | { |
584 | float major = 1; |
585 | float minor = *((float*) userdata); |
586 | float theta = uv[0] * 2 * PAR_PI; |
587 | float phi = uv[1] * 2 * PAR_PI; |
588 | float beta = major + minor * cosf(phi); |
589 | xyz[0] = cosf(theta) * beta; |
590 | xyz[1] = sinf(theta) * beta; |
591 | xyz[2] = sinf(phi) * minor; |
592 | } |
593 | |
594 | static void par_shapes__trefoil(float const* uv, float* xyz, void* userdata) |
595 | { |
596 | float minor = *((float*) userdata); |
597 | const float a = 0.5f; |
598 | const float b = 0.3f; |
599 | const float c = 0.5f; |
600 | const float d = minor * 0.1f; |
601 | const float u = (1 - uv[0]) * 4 * PAR_PI; |
602 | const float v = uv[1] * 2 * PAR_PI; |
603 | const float r = a + b * cos(1.5f * u); |
604 | const float x = r * cos(u); |
605 | const float y = r * sin(u); |
606 | const float z = c * sin(1.5f * u); |
607 | float q[3]; |
608 | q[0] = |
609 | -1.5f * b * sin(1.5f * u) * cos(u) - (a + b * cos(1.5f * u)) * sin(u); |
610 | q[1] = |
611 | -1.5f * b * sin(1.5f * u) * sin(u) + (a + b * cos(1.5f * u)) * cos(u); |
612 | q[2] = 1.5f * c * cos(1.5f * u); |
613 | par_shapes__normalize3(q); |
614 | float qvn[3] = {q[1], -q[0], 0}; |
615 | par_shapes__normalize3(qvn); |
616 | float ww[3]; |
617 | par_shapes__cross3(ww, q, qvn); |
618 | xyz[0] = x + d * (qvn[0] * cos(v) + ww[0] * sin(v)); |
619 | xyz[1] = y + d * (qvn[1] * cos(v) + ww[1] * sin(v)); |
620 | xyz[2] = z + d * ww[2] * sin(v); |
621 | } |
622 | |
623 | void par_shapes_merge(par_shapes_mesh* dst, par_shapes_mesh const* src) |
624 | { |
625 | PAR_SHAPES_T offset = dst->npoints; |
626 | int npoints = dst->npoints + src->npoints; |
627 | int vecsize = sizeof(float) * 3; |
628 | dst->points = PAR_REALLOC(float, dst->points, 3 * npoints); |
629 | memcpy(dst->points + 3 * dst->npoints, src->points, vecsize * src->npoints); |
630 | dst->npoints = npoints; |
631 | if (src->normals || dst->normals) { |
632 | dst->normals = PAR_REALLOC(float, dst->normals, 3 * npoints); |
633 | if (src->normals) { |
634 | memcpy(dst->normals + 3 * offset, src->normals, |
635 | vecsize * src->npoints); |
636 | } |
637 | } |
638 | if (src->tcoords || dst->tcoords) { |
639 | int uvsize = sizeof(float) * 2; |
640 | dst->tcoords = PAR_REALLOC(float, dst->tcoords, 2 * npoints); |
641 | if (src->tcoords) { |
642 | memcpy(dst->tcoords + 2 * offset, src->tcoords, |
643 | uvsize * src->npoints); |
644 | } |
645 | } |
646 | int ntriangles = dst->ntriangles + src->ntriangles; |
647 | dst->triangles = PAR_REALLOC(PAR_SHAPES_T, dst->triangles, 3 * ntriangles); |
648 | PAR_SHAPES_T* ptriangles = dst->triangles + 3 * dst->ntriangles; |
649 | PAR_SHAPES_T const* striangles = src->triangles; |
650 | for (int i = 0; i < src->ntriangles; i++) { |
651 | *ptriangles++ = offset + *striangles++; |
652 | *ptriangles++ = offset + *striangles++; |
653 | *ptriangles++ = offset + *striangles++; |
654 | } |
655 | dst->ntriangles = ntriangles; |
656 | } |
657 | |
658 | par_shapes_mesh* par_shapes_create_disk(float radius, int slices, |
659 | float const* center, float const* normal) |
660 | { |
661 | par_shapes_mesh* mesh = PAR_CALLOC(par_shapes_mesh, 1); |
662 | mesh->npoints = slices + 1; |
663 | mesh->points = PAR_MALLOC(float, 3 * mesh->npoints); |
664 | float* points = mesh->points; |
665 | *points++ = 0; |
666 | *points++ = 0; |
667 | *points++ = 0; |
668 | for (int i = 0; i < slices; i++) { |
669 | float theta = i * PAR_PI * 2 / slices; |
670 | *points++ = radius * cos(theta); |
671 | *points++ = radius * sin(theta); |
672 | *points++ = 0; |
673 | } |
674 | float nnormal[3] = {normal[0], normal[1], normal[2]}; |
675 | par_shapes__normalize3(nnormal); |
676 | mesh->normals = PAR_MALLOC(float, 3 * mesh->npoints); |
677 | float* norms = mesh->normals; |
678 | for (int i = 0; i < mesh->npoints; i++) { |
679 | *norms++ = nnormal[0]; |
680 | *norms++ = nnormal[1]; |
681 | *norms++ = nnormal[2]; |
682 | } |
683 | mesh->ntriangles = slices; |
684 | mesh->triangles = PAR_MALLOC(PAR_SHAPES_T, 3 * mesh->ntriangles); |
685 | PAR_SHAPES_T* triangles = mesh->triangles; |
686 | for (int i = 0; i < slices; i++) { |
687 | *triangles++ = 0; |
688 | *triangles++ = 1 + i; |
689 | *triangles++ = 1 + (i + 1) % slices; |
690 | } |
691 | float k[3] = {0, 0, -1}; |
692 | float axis[3]; |
693 | par_shapes__cross3(axis, nnormal, k); |
694 | par_shapes__normalize3(axis); |
695 | par_shapes_rotate(mesh, acos(nnormal[2]), axis); |
696 | par_shapes_translate(mesh, center[0], center[1], center[2]); |
697 | return mesh; |
698 | } |
699 | |
700 | par_shapes_mesh* par_shapes_create_empty() |
701 | { |
702 | return PAR_CALLOC(par_shapes_mesh, 1); |
703 | } |
704 | |
705 | void par_shapes_translate(par_shapes_mesh* m, float x, float y, float z) |
706 | { |
707 | float* points = m->points; |
708 | for (int i = 0; i < m->npoints; i++) { |
709 | *points++ += x; |
710 | *points++ += y; |
711 | *points++ += z; |
712 | } |
713 | } |
714 | |
715 | void par_shapes_rotate(par_shapes_mesh* mesh, float radians, float const* axis) |
716 | { |
717 | float s = sinf(radians); |
718 | float c = cosf(radians); |
719 | float x = axis[0]; |
720 | float y = axis[1]; |
721 | float z = axis[2]; |
722 | float xy = x * y; |
723 | float yz = y * z; |
724 | float zx = z * x; |
725 | float oneMinusC = 1.0f - c; |
726 | float col0[3] = { |
727 | (((x * x) * oneMinusC) + c), |
728 | ((xy * oneMinusC) + (z * s)), ((zx * oneMinusC) - (y * s)) |
729 | }; |
730 | float col1[3] = { |
731 | ((xy * oneMinusC) - (z * s)), |
732 | (((y * y) * oneMinusC) + c), ((yz * oneMinusC) + (x * s)) |
733 | }; |
734 | float col2[3] = { |
735 | ((zx * oneMinusC) + (y * s)), |
736 | ((yz * oneMinusC) - (x * s)), (((z * z) * oneMinusC) + c) |
737 | }; |
738 | float* p = mesh->points; |
739 | for (int i = 0; i < mesh->npoints; i++, p += 3) { |
740 | float x = col0[0] * p[0] + col1[0] * p[1] + col2[0] * p[2]; |
741 | float y = col0[1] * p[0] + col1[1] * p[1] + col2[1] * p[2]; |
742 | float z = col0[2] * p[0] + col1[2] * p[1] + col2[2] * p[2]; |
743 | p[0] = x; |
744 | p[1] = y; |
745 | p[2] = z; |
746 | } |
747 | p = mesh->normals; |
748 | if (p) { |
749 | for (int i = 0; i < mesh->npoints; i++, p += 3) { |
750 | float x = col0[0] * p[0] + col1[0] * p[1] + col2[0] * p[2]; |
751 | float y = col0[1] * p[0] + col1[1] * p[1] + col2[1] * p[2]; |
752 | float z = col0[2] * p[0] + col1[2] * p[1] + col2[2] * p[2]; |
753 | p[0] = x; |
754 | p[1] = y; |
755 | p[2] = z; |
756 | } |
757 | } |
758 | } |
759 | |
760 | void par_shapes_scale(par_shapes_mesh* m, float x, float y, float z) |
761 | { |
762 | float* points = m->points; |
763 | for (int i = 0; i < m->npoints; i++) { |
764 | *points++ *= x; |
765 | *points++ *= y; |
766 | *points++ *= z; |
767 | } |
768 | } |
769 | |
770 | void par_shapes_merge_and_free(par_shapes_mesh* dst, par_shapes_mesh* src) |
771 | { |
772 | par_shapes_merge(dst, src); |
773 | par_shapes_free_mesh(src); |
774 | } |
775 | |
776 | void par_shapes_compute_aabb(par_shapes_mesh const* m, float* aabb) |
777 | { |
778 | float* points = m->points; |
779 | aabb[0] = aabb[3] = points[0]; |
780 | aabb[1] = aabb[4] = points[1]; |
781 | aabb[2] = aabb[5] = points[2]; |
782 | points += 3; |
783 | for (int i = 1; i < m->npoints; i++, points += 3) { |
784 | aabb[0] = PAR_MIN(points[0], aabb[0]); |
785 | aabb[1] = PAR_MIN(points[1], aabb[1]); |
786 | aabb[2] = PAR_MIN(points[2], aabb[2]); |
787 | aabb[3] = PAR_MAX(points[0], aabb[3]); |
788 | aabb[4] = PAR_MAX(points[1], aabb[4]); |
789 | aabb[5] = PAR_MAX(points[2], aabb[5]); |
790 | } |
791 | } |
792 | |
793 | void par_shapes_invert(par_shapes_mesh* m, int face, int nfaces) |
794 | { |
795 | nfaces = nfaces ? nfaces : m->ntriangles; |
796 | PAR_SHAPES_T* tri = m->triangles + face * 3; |
797 | for (int i = 0; i < nfaces; i++) { |
798 | PAR_SWAP(PAR_SHAPES_T, tri[0], tri[2]); |
799 | tri += 3; |
800 | } |
801 | } |
802 | |
803 | par_shapes_mesh* par_shapes_create_icosahedron() |
804 | { |
805 | static float verts[] = { |
806 | 0.000, 0.000, 1.000, |
807 | 0.894, 0.000, 0.447, |
808 | 0.276, 0.851, 0.447, |
809 | -0.724, 0.526, 0.447, |
810 | -0.724, -0.526, 0.447, |
811 | 0.276, -0.851, 0.447, |
812 | 0.724, 0.526, -0.447, |
813 | -0.276, 0.851, -0.447, |
814 | -0.894, 0.000, -0.447, |
815 | -0.276, -0.851, -0.447, |
816 | 0.724, -0.526, -0.447, |
817 | 0.000, 0.000, -1.000 |
818 | }; |
819 | static PAR_SHAPES_T faces[] = { |
820 | 0,1,2, |
821 | 0,2,3, |
822 | 0,3,4, |
823 | 0,4,5, |
824 | 0,5,1, |
825 | 7,6,11, |
826 | 8,7,11, |
827 | 9,8,11, |
828 | 10,9,11, |
829 | 6,10,11, |
830 | 6,2,1, |
831 | 7,3,2, |
832 | 8,4,3, |
833 | 9,5,4, |
834 | 10,1,5, |
835 | 6,7,2, |
836 | 7,8,3, |
837 | 8,9,4, |
838 | 9,10,5, |
839 | 10,6,1 |
840 | }; |
841 | par_shapes_mesh* mesh = PAR_CALLOC(par_shapes_mesh, 1); |
842 | mesh->npoints = sizeof(verts) / sizeof(verts[0]) / 3; |
843 | mesh->points = PAR_MALLOC(float, sizeof(verts) / 4); |
844 | memcpy(mesh->points, verts, sizeof(verts)); |
845 | mesh->ntriangles = sizeof(faces) / sizeof(faces[0]) / 3; |
846 | mesh->triangles = PAR_MALLOC(PAR_SHAPES_T, sizeof(faces) / 2); |
847 | memcpy(mesh->triangles, faces, sizeof(faces)); |
848 | return mesh; |
849 | } |
850 | |
851 | par_shapes_mesh* par_shapes_create_dodecahedron() |
852 | { |
853 | static float verts[20 * 3] = { |
854 | 0.607, 0.000, 0.795, |
855 | 0.188, 0.577, 0.795, |
856 | -0.491, 0.357, 0.795, |
857 | -0.491, -0.357, 0.795, |
858 | 0.188, -0.577, 0.795, |
859 | 0.982, 0.000, 0.188, |
860 | 0.304, 0.934, 0.188, |
861 | -0.795, 0.577, 0.188, |
862 | -0.795, -0.577, 0.188, |
863 | 0.304, -0.934, 0.188, |
864 | 0.795, 0.577, -0.188, |
865 | -0.304, 0.934, -0.188, |
866 | -0.982, 0.000, -0.188, |
867 | -0.304, -0.934, -0.188, |
868 | 0.795, -0.577, -0.188, |
869 | 0.491, 0.357, -0.795, |
870 | -0.188, 0.577, -0.795, |
871 | -0.607, 0.000, -0.795, |
872 | -0.188, -0.577, -0.795, |
873 | 0.491, -0.357, -0.795, |
874 | }; |
875 | static PAR_SHAPES_T pentagons[12 * 5] = { |
876 | 0,1,2,3,4, |
877 | 5,10,6,1,0, |
878 | 6,11,7,2,1, |
879 | 7,12,8,3,2, |
880 | 8,13,9,4,3, |
881 | 9,14,5,0,4, |
882 | 15,16,11,6,10, |
883 | 16,17,12,7,11, |
884 | 17,18,13,8,12, |
885 | 18,19,14,9,13, |
886 | 19,15,10,5,14, |
887 | 19,18,17,16,15 |
888 | }; |
889 | int npentagons = sizeof(pentagons) / sizeof(pentagons[0]) / 5; |
890 | par_shapes_mesh* mesh = PAR_CALLOC(par_shapes_mesh, 1); |
891 | int ncorners = sizeof(verts) / sizeof(verts[0]) / 3; |
892 | mesh->npoints = ncorners; |
893 | mesh->points = PAR_MALLOC(float, mesh->npoints * 3); |
894 | memcpy(mesh->points, verts, sizeof(verts)); |
895 | PAR_SHAPES_T const* pentagon = pentagons; |
896 | mesh->ntriangles = npentagons * 3; |
897 | mesh->triangles = PAR_MALLOC(PAR_SHAPES_T, mesh->ntriangles * 3); |
898 | PAR_SHAPES_T* tris = mesh->triangles; |
899 | for (int p = 0; p < npentagons; p++, pentagon += 5) { |
900 | *tris++ = pentagon[0]; |
901 | *tris++ = pentagon[1]; |
902 | *tris++ = pentagon[2]; |
903 | *tris++ = pentagon[0]; |
904 | *tris++ = pentagon[2]; |
905 | *tris++ = pentagon[3]; |
906 | *tris++ = pentagon[0]; |
907 | *tris++ = pentagon[3]; |
908 | *tris++ = pentagon[4]; |
909 | } |
910 | return mesh; |
911 | } |
912 | |
913 | par_shapes_mesh* par_shapes_create_octahedron() |
914 | { |
915 | static float verts[6 * 3] = { |
916 | 0.000, 0.000, 1.000, |
917 | 1.000, 0.000, 0.000, |
918 | 0.000, 1.000, 0.000, |
919 | -1.000, 0.000, 0.000, |
920 | 0.000, -1.000, 0.000, |
921 | 0.000, 0.000, -1.000 |
922 | }; |
923 | static PAR_SHAPES_T triangles[8 * 3] = { |
924 | 0,1,2, |
925 | 0,2,3, |
926 | 0,3,4, |
927 | 0,4,1, |
928 | 2,1,5, |
929 | 3,2,5, |
930 | 4,3,5, |
931 | 1,4,5, |
932 | }; |
933 | int ntris = sizeof(triangles) / sizeof(triangles[0]) / 3; |
934 | par_shapes_mesh* mesh = PAR_CALLOC(par_shapes_mesh, 1); |
935 | int ncorners = sizeof(verts) / sizeof(verts[0]) / 3; |
936 | mesh->npoints = ncorners; |
937 | mesh->points = PAR_MALLOC(float, mesh->npoints * 3); |
938 | memcpy(mesh->points, verts, sizeof(verts)); |
939 | PAR_SHAPES_T const* triangle = triangles; |
940 | mesh->ntriangles = ntris; |
941 | mesh->triangles = PAR_MALLOC(PAR_SHAPES_T, mesh->ntriangles * 3); |
942 | PAR_SHAPES_T* tris = mesh->triangles; |
943 | for (int p = 0; p < ntris; p++) { |
944 | *tris++ = *triangle++; |
945 | *tris++ = *triangle++; |
946 | *tris++ = *triangle++; |
947 | } |
948 | return mesh; |
949 | } |
950 | |
951 | par_shapes_mesh* par_shapes_create_tetrahedron() |
952 | { |
953 | static float verts[4 * 3] = { |
954 | 0.000, 1.333, 0, |
955 | 0.943, 0, 0, |
956 | -0.471, 0, 0.816, |
957 | -0.471, 0, -0.816, |
958 | }; |
959 | static PAR_SHAPES_T triangles[4 * 3] = { |
960 | 2,1,0, |
961 | 3,2,0, |
962 | 1,3,0, |
963 | 1,2,3, |
964 | }; |
965 | int ntris = sizeof(triangles) / sizeof(triangles[0]) / 3; |
966 | par_shapes_mesh* mesh = PAR_CALLOC(par_shapes_mesh, 1); |
967 | int ncorners = sizeof(verts) / sizeof(verts[0]) / 3; |
968 | mesh->npoints = ncorners; |
969 | mesh->points = PAR_MALLOC(float, mesh->npoints * 3); |
970 | memcpy(mesh->points, verts, sizeof(verts)); |
971 | PAR_SHAPES_T const* triangle = triangles; |
972 | mesh->ntriangles = ntris; |
973 | mesh->triangles = PAR_MALLOC(PAR_SHAPES_T, mesh->ntriangles * 3); |
974 | PAR_SHAPES_T* tris = mesh->triangles; |
975 | for (int p = 0; p < ntris; p++) { |
976 | *tris++ = *triangle++; |
977 | *tris++ = *triangle++; |
978 | *tris++ = *triangle++; |
979 | } |
980 | return mesh; |
981 | } |
982 | |
983 | par_shapes_mesh* par_shapes_create_cube() |
984 | { |
985 | static float verts[8 * 3] = { |
986 | 0, 0, 0, // 0 |
987 | 0, 1, 0, // 1 |
988 | 1, 1, 0, // 2 |
989 | 1, 0, 0, // 3 |
990 | 0, 0, 1, // 4 |
991 | 0, 1, 1, // 5 |
992 | 1, 1, 1, // 6 |
993 | 1, 0, 1, // 7 |
994 | }; |
995 | static PAR_SHAPES_T quads[6 * 4] = { |
996 | 7,6,5,4, // front |
997 | 0,1,2,3, // back |
998 | 6,7,3,2, // right |
999 | 5,6,2,1, // top |
1000 | 4,5,1,0, // left |
1001 | 7,4,0,3, // bottom |
1002 | }; |
1003 | int nquads = sizeof(quads) / sizeof(quads[0]) / 4; |
1004 | par_shapes_mesh* mesh = PAR_CALLOC(par_shapes_mesh, 1); |
1005 | int ncorners = sizeof(verts) / sizeof(verts[0]) / 3; |
1006 | mesh->npoints = ncorners; |
1007 | mesh->points = PAR_MALLOC(float, mesh->npoints * 3); |
1008 | memcpy(mesh->points, verts, sizeof(verts)); |
1009 | PAR_SHAPES_T const* quad = quads; |
1010 | mesh->ntriangles = nquads * 2; |
1011 | mesh->triangles = PAR_MALLOC(PAR_SHAPES_T, mesh->ntriangles * 3); |
1012 | PAR_SHAPES_T* tris = mesh->triangles; |
1013 | for (int p = 0; p < nquads; p++, quad += 4) { |
1014 | *tris++ = quad[0]; |
1015 | *tris++ = quad[1]; |
1016 | *tris++ = quad[2]; |
1017 | *tris++ = quad[2]; |
1018 | *tris++ = quad[3]; |
1019 | *tris++ = quad[0]; |
1020 | } |
1021 | return mesh; |
1022 | } |
1023 | |
1024 | typedef struct { |
1025 | char* cmd; |
1026 | char* arg; |
1027 | } par_shapes__command; |
1028 | |
1029 | typedef struct { |
1030 | char const* name; |
1031 | int weight; |
1032 | int ncommands; |
1033 | par_shapes__command* commands; |
1034 | } par_shapes__rule; |
1035 | |
1036 | typedef struct { |
1037 | int pc; |
1038 | float position[3]; |
1039 | float scale[3]; |
1040 | par_shapes_mesh* orientation; |
1041 | par_shapes__rule* rule; |
1042 | } par_shapes__stackframe; |
1043 | |
1044 | static par_shapes__rule* par_shapes__pick_rule(const char* name, |
1045 | par_shapes__rule* rules, int nrules) |
1046 | { |
1047 | par_shapes__rule* rule = 0; |
1048 | int total = 0; |
1049 | for (int i = 0; i < nrules; i++) { |
1050 | rule = rules + i; |
1051 | if (!strcmp(rule->name, name)) { |
1052 | total += rule->weight; |
1053 | } |
1054 | } |
1055 | float r = (float) rand() / RAND_MAX; |
1056 | float t = 0; |
1057 | for (int i = 0; i < nrules; i++) { |
1058 | rule = rules + i; |
1059 | if (!strcmp(rule->name, name)) { |
1060 | t += (float) rule->weight / total; |
1061 | if (t >= r) { |
1062 | return rule; |
1063 | } |
1064 | } |
1065 | } |
1066 | return rule; |
1067 | } |
1068 | |
1069 | static par_shapes_mesh* par_shapes__create_turtle() |
1070 | { |
1071 | const float xaxis[] = {1, 0, 0}; |
1072 | const float yaxis[] = {0, 1, 0}; |
1073 | const float zaxis[] = {0, 0, 1}; |
1074 | par_shapes_mesh* turtle = PAR_CALLOC(par_shapes_mesh, 1); |
1075 | turtle->npoints = 3; |
1076 | turtle->points = PAR_CALLOC(float, turtle->npoints * 3); |
1077 | par_shapes__copy3(turtle->points + 0, xaxis); |
1078 | par_shapes__copy3(turtle->points + 3, yaxis); |
1079 | par_shapes__copy3(turtle->points + 6, zaxis); |
1080 | return turtle; |
1081 | } |
1082 | |
1083 | static par_shapes_mesh* par_shapes__apply_turtle(par_shapes_mesh* mesh, |
1084 | par_shapes_mesh* turtle, float const* pos, float const* scale) |
1085 | { |
1086 | par_shapes_mesh* m = par_shapes_clone(mesh, 0); |
1087 | for (int p = 0; p < m->npoints; p++) { |
1088 | float* pt = m->points + p * 3; |
1089 | pt[0] *= scale[0]; |
1090 | pt[1] *= scale[1]; |
1091 | pt[2] *= scale[2]; |
1092 | par_shapes__transform3(pt, |
1093 | turtle->points + 0, turtle->points + 3, turtle->points + 6); |
1094 | pt[0] += pos[0]; |
1095 | pt[1] += pos[1]; |
1096 | pt[2] += pos[2]; |
1097 | } |
1098 | return m; |
1099 | } |
1100 | |
1101 | static void par_shapes__connect(par_shapes_mesh* scene, |
1102 | par_shapes_mesh* cylinder, int slices) |
1103 | { |
1104 | int stacks = 1; |
1105 | int npoints = (slices + 1) * (stacks + 1); |
1106 | assert(scene->npoints >= npoints && "Cannot connect to empty scene." ); |
1107 | |
1108 | // Create the new point list. |
1109 | npoints = scene->npoints + (slices + 1); |
1110 | float* points = PAR_MALLOC(float, npoints * 3); |
1111 | memcpy(points, scene->points, sizeof(float) * scene->npoints * 3); |
1112 | float* newpts = points + scene->npoints * 3; |
1113 | memcpy(newpts, cylinder->points + (slices + 1) * 3, |
1114 | sizeof(float) * (slices + 1) * 3); |
1115 | PAR_FREE(scene->points); |
1116 | scene->points = points; |
1117 | |
1118 | // Create the new triangle list. |
1119 | int ntriangles = scene->ntriangles + 2 * slices * stacks; |
1120 | PAR_SHAPES_T* triangles = PAR_MALLOC(PAR_SHAPES_T, ntriangles * 3); |
1121 | memcpy(triangles, scene->triangles, 2 * scene->ntriangles * 3); |
1122 | int v = scene->npoints - (slices + 1); |
1123 | PAR_SHAPES_T* face = triangles + scene->ntriangles * 3; |
1124 | for (int stack = 0; stack < stacks; stack++) { |
1125 | for (int slice = 0; slice < slices; slice++) { |
1126 | int next = slice + 1; |
1127 | *face++ = v + slice + slices + 1; |
1128 | *face++ = v + next; |
1129 | *face++ = v + slice; |
1130 | *face++ = v + slice + slices + 1; |
1131 | *face++ = v + next + slices + 1; |
1132 | *face++ = v + next; |
1133 | } |
1134 | v += slices + 1; |
1135 | } |
1136 | PAR_FREE(scene->triangles); |
1137 | scene->triangles = triangles; |
1138 | |
1139 | scene->npoints = npoints; |
1140 | scene->ntriangles = ntriangles; |
1141 | } |
1142 | |
1143 | par_shapes_mesh* par_shapes_create_lsystem(char const* text, int slices, |
1144 | int maxdepth) |
1145 | { |
1146 | char* program; |
1147 | program = PAR_MALLOC(char, strlen(text) + 1); |
1148 | |
1149 | // The first pass counts the number of rules and commands. |
1150 | strcpy(program, text); |
1151 | char *cmd = strtok(program, " " ); |
1152 | int nrules = 1; |
1153 | int ncommands = 0; |
1154 | while (cmd) { |
1155 | char *arg = strtok(0, " " ); |
1156 | if (!arg) { |
1157 | //puts("lsystem error: unexpected end of program."); |
1158 | break; |
1159 | } |
1160 | if (!strcmp(cmd, "rule" )) { |
1161 | nrules++; |
1162 | } else { |
1163 | ncommands++; |
1164 | } |
1165 | cmd = strtok(0, " " ); |
1166 | } |
1167 | |
1168 | // Allocate space. |
1169 | par_shapes__rule* rules = PAR_MALLOC(par_shapes__rule, nrules); |
1170 | par_shapes__command* commands = PAR_MALLOC(par_shapes__command, ncommands); |
1171 | |
1172 | // Initialize the entry rule. |
1173 | par_shapes__rule* current_rule = &rules[0]; |
1174 | par_shapes__command* current_command = &commands[0]; |
1175 | current_rule->name = "entry" ; |
1176 | current_rule->weight = 1; |
1177 | current_rule->ncommands = 0; |
1178 | current_rule->commands = current_command; |
1179 | |
1180 | // The second pass fills in the structures. |
1181 | strcpy(program, text); |
1182 | cmd = strtok(program, " " ); |
1183 | while (cmd) { |
1184 | char *arg = strtok(0, " " ); |
1185 | if (!strcmp(cmd, "rule" )) { |
1186 | current_rule++; |
1187 | |
1188 | // Split the argument into a rule name and weight. |
1189 | char* dot = strchr(arg, '.'); |
1190 | if (dot) { |
1191 | current_rule->weight = atoi(dot + 1); |
1192 | *dot = 0; |
1193 | } else { |
1194 | current_rule->weight = 1; |
1195 | } |
1196 | |
1197 | current_rule->name = arg; |
1198 | current_rule->ncommands = 0; |
1199 | current_rule->commands = current_command; |
1200 | } else { |
1201 | current_rule->ncommands++; |
1202 | current_command->cmd = cmd; |
1203 | current_command->arg = arg; |
1204 | current_command++; |
1205 | } |
1206 | cmd = strtok(0, " " ); |
1207 | } |
1208 | |
1209 | // For testing purposes, dump out the parsed program. |
1210 | #ifdef TEST_PARSE |
1211 | /* |
1212 | for (int i = 0; i < nrules; i++) { |
1213 | par_shapes__rule rule = rules[i]; |
1214 | printf("rule %s.%d\n", rule.name, rule.weight); |
1215 | for (int c = 0; c < rule.ncommands; c++) { |
1216 | par_shapes__command cmd = rule.commands[c]; |
1217 | printf("\t%s %s\n", cmd.cmd, cmd.arg); |
1218 | } |
1219 | } |
1220 | */ |
1221 | #endif |
1222 | |
1223 | // Instantiate the aggregated shape and the template shapes. |
1224 | par_shapes_mesh* scene = PAR_CALLOC(par_shapes_mesh, 1); |
1225 | par_shapes_mesh* tube = par_shapes_create_cylinder(slices, 1); |
1226 | par_shapes_mesh* turtle = par_shapes__create_turtle(); |
1227 | |
1228 | // We're not attempting to support texture coordinates and normals |
1229 | // with L-systems, so remove them from the template shape. |
1230 | PAR_FREE(tube->normals); |
1231 | PAR_FREE(tube->tcoords); |
1232 | tube->normals = 0; |
1233 | tube->tcoords = 0; |
1234 | |
1235 | const float xaxis[] = {1, 0, 0}; |
1236 | const float yaxis[] = {0, 1, 0}; |
1237 | const float zaxis[] = {0, 0, 1}; |
1238 | const float units[] = {1, 1, 1}; |
1239 | |
1240 | // Execute the L-system program until the stack size is 0. |
1241 | par_shapes__stackframe* stack = |
1242 | PAR_CALLOC(par_shapes__stackframe, maxdepth); |
1243 | int stackptr = 0; |
1244 | stack[0].orientation = turtle; |
1245 | stack[0].rule = &rules[0]; |
1246 | par_shapes__copy3(stack[0].scale, units); |
1247 | while (stackptr >= 0) { |
1248 | par_shapes__stackframe* frame = &stack[stackptr]; |
1249 | par_shapes__rule* rule = frame->rule; |
1250 | par_shapes_mesh* turtle = frame->orientation; |
1251 | float* position = frame->position; |
1252 | float* scale = frame->scale; |
1253 | if (frame->pc >= rule->ncommands) { |
1254 | par_shapes_free_mesh(turtle); |
1255 | stackptr--; |
1256 | continue; |
1257 | } |
1258 | |
1259 | par_shapes__command* cmd = rule->commands + (frame->pc++); |
1260 | #ifdef DUMP_TRACE |
1261 | //printf("%5s %5s %5s:%d %03d\n", cmd->cmd, cmd->arg, rule->name, frame->pc - 1, stackptr); |
1262 | #endif |
1263 | |
1264 | float value; |
1265 | if (!strcmp(cmd->cmd, "shape" )) { |
1266 | par_shapes_mesh* m = par_shapes__apply_turtle(tube, turtle, |
1267 | position, scale); |
1268 | if (!strcmp(cmd->arg, "connect" )) { |
1269 | par_shapes__connect(scene, m, slices); |
1270 | } else { |
1271 | par_shapes_merge(scene, m); |
1272 | } |
1273 | par_shapes_free_mesh(m); |
1274 | } else if (!strcmp(cmd->cmd, "call" ) && stackptr < maxdepth - 1) { |
1275 | rule = par_shapes__pick_rule(cmd->arg, rules, nrules); |
1276 | frame = &stack[++stackptr]; |
1277 | frame->rule = rule; |
1278 | frame->orientation = par_shapes_clone(turtle, 0); |
1279 | frame->pc = 0; |
1280 | par_shapes__copy3(frame->scale, scale); |
1281 | par_shapes__copy3(frame->position, position); |
1282 | continue; |
1283 | } else { |
1284 | value = atof(cmd->arg); |
1285 | if (!strcmp(cmd->cmd, "rx" )) { |
1286 | par_shapes_rotate(turtle, value * PAR_PI / 180.0, xaxis); |
1287 | } else if (!strcmp(cmd->cmd, "ry" )) { |
1288 | par_shapes_rotate(turtle, value * PAR_PI / 180.0, yaxis); |
1289 | } else if (!strcmp(cmd->cmd, "rz" )) { |
1290 | par_shapes_rotate(turtle, value * PAR_PI / 180.0, zaxis); |
1291 | } else if (!strcmp(cmd->cmd, "tx" )) { |
1292 | float vec[3] = {value, 0, 0}; |
1293 | float t[3] = { |
1294 | par_shapes__dot3(turtle->points + 0, vec), |
1295 | par_shapes__dot3(turtle->points + 3, vec), |
1296 | par_shapes__dot3(turtle->points + 6, vec) |
1297 | }; |
1298 | par_shapes__add3(position, t); |
1299 | } else if (!strcmp(cmd->cmd, "ty" )) { |
1300 | float vec[3] = {0, value, 0}; |
1301 | float t[3] = { |
1302 | par_shapes__dot3(turtle->points + 0, vec), |
1303 | par_shapes__dot3(turtle->points + 3, vec), |
1304 | par_shapes__dot3(turtle->points + 6, vec) |
1305 | }; |
1306 | par_shapes__add3(position, t); |
1307 | } else if (!strcmp(cmd->cmd, "tz" )) { |
1308 | float vec[3] = {0, 0, value}; |
1309 | float t[3] = { |
1310 | par_shapes__dot3(turtle->points + 0, vec), |
1311 | par_shapes__dot3(turtle->points + 3, vec), |
1312 | par_shapes__dot3(turtle->points + 6, vec) |
1313 | }; |
1314 | par_shapes__add3(position, t); |
1315 | } else if (!strcmp(cmd->cmd, "sx" )) { |
1316 | scale[0] *= value; |
1317 | } else if (!strcmp(cmd->cmd, "sy" )) { |
1318 | scale[1] *= value; |
1319 | } else if (!strcmp(cmd->cmd, "sz" )) { |
1320 | scale[2] *= value; |
1321 | } else if (!strcmp(cmd->cmd, "sa" )) { |
1322 | scale[0] *= value; |
1323 | scale[1] *= value; |
1324 | scale[2] *= value; |
1325 | } |
1326 | } |
1327 | } |
1328 | PAR_FREE(stack); |
1329 | PAR_FREE(program); |
1330 | PAR_FREE(rules); |
1331 | PAR_FREE(commands); |
1332 | return scene; |
1333 | } |
1334 | |
1335 | void par_shapes_unweld(par_shapes_mesh* mesh, bool create_indices) |
1336 | { |
1337 | int npoints = mesh->ntriangles * 3; |
1338 | float* points = PAR_MALLOC(float, 3 * npoints); |
1339 | float* dst = points; |
1340 | PAR_SHAPES_T const* index = mesh->triangles; |
1341 | for (int i = 0; i < npoints; i++) { |
1342 | float const* src = mesh->points + 3 * (*index++); |
1343 | *dst++ = src[0]; |
1344 | *dst++ = src[1]; |
1345 | *dst++ = src[2]; |
1346 | } |
1347 | PAR_FREE(mesh->points); |
1348 | mesh->points = points; |
1349 | mesh->npoints = npoints; |
1350 | if (create_indices) { |
1351 | PAR_SHAPES_T* tris = PAR_MALLOC(PAR_SHAPES_T, 3 * mesh->ntriangles); |
1352 | PAR_SHAPES_T* index = tris; |
1353 | for (int i = 0; i < mesh->ntriangles * 3; i++) { |
1354 | *index++ = i; |
1355 | } |
1356 | PAR_FREE(mesh->triangles); |
1357 | mesh->triangles = tris; |
1358 | } |
1359 | } |
1360 | |
1361 | void par_shapes_compute_normals(par_shapes_mesh* m) |
1362 | { |
1363 | PAR_FREE(m->normals); |
1364 | m->normals = PAR_CALLOC(float, m->npoints * 3); |
1365 | PAR_SHAPES_T const* triangle = m->triangles; |
1366 | float next[3], prev[3], cp[3]; |
1367 | for (int f = 0; f < m->ntriangles; f++, triangle += 3) { |
1368 | float const* pa = m->points + 3 * triangle[0]; |
1369 | float const* pb = m->points + 3 * triangle[1]; |
1370 | float const* pc = m->points + 3 * triangle[2]; |
1371 | par_shapes__copy3(next, pb); |
1372 | par_shapes__subtract3(next, pa); |
1373 | par_shapes__copy3(prev, pc); |
1374 | par_shapes__subtract3(prev, pa); |
1375 | par_shapes__cross3(cp, next, prev); |
1376 | par_shapes__add3(m->normals + 3 * triangle[0], cp); |
1377 | par_shapes__copy3(next, pc); |
1378 | par_shapes__subtract3(next, pb); |
1379 | par_shapes__copy3(prev, pa); |
1380 | par_shapes__subtract3(prev, pb); |
1381 | par_shapes__cross3(cp, next, prev); |
1382 | par_shapes__add3(m->normals + 3 * triangle[1], cp); |
1383 | par_shapes__copy3(next, pa); |
1384 | par_shapes__subtract3(next, pc); |
1385 | par_shapes__copy3(prev, pb); |
1386 | par_shapes__subtract3(prev, pc); |
1387 | par_shapes__cross3(cp, next, prev); |
1388 | par_shapes__add3(m->normals + 3 * triangle[2], cp); |
1389 | } |
1390 | float* normal = m->normals; |
1391 | for (int p = 0; p < m->npoints; p++, normal += 3) { |
1392 | par_shapes__normalize3(normal); |
1393 | } |
1394 | } |
1395 | |
1396 | static void par_shapes__subdivide(par_shapes_mesh* mesh) |
1397 | { |
1398 | assert(mesh->npoints == mesh->ntriangles * 3 && "Must be unwelded." ); |
1399 | int ntriangles = mesh->ntriangles * 4; |
1400 | int npoints = ntriangles * 3; |
1401 | float* points = PAR_CALLOC(float, npoints * 3); |
1402 | float* dpoint = points; |
1403 | float const* spoint = mesh->points; |
1404 | for (int t = 0; t < mesh->ntriangles; t++, spoint += 9, dpoint += 3) { |
1405 | float const* a = spoint; |
1406 | float const* b = spoint + 3; |
1407 | float const* c = spoint + 6; |
1408 | float const* p0 = dpoint; |
1409 | float const* p1 = dpoint + 3; |
1410 | float const* p2 = dpoint + 6; |
1411 | par_shapes__mix3(dpoint, a, b, 0.5); |
1412 | par_shapes__mix3(dpoint += 3, b, c, 0.5); |
1413 | par_shapes__mix3(dpoint += 3, a, c, 0.5); |
1414 | par_shapes__add3(dpoint += 3, a); |
1415 | par_shapes__add3(dpoint += 3, p0); |
1416 | par_shapes__add3(dpoint += 3, p2); |
1417 | par_shapes__add3(dpoint += 3, p0); |
1418 | par_shapes__add3(dpoint += 3, b); |
1419 | par_shapes__add3(dpoint += 3, p1); |
1420 | par_shapes__add3(dpoint += 3, p2); |
1421 | par_shapes__add3(dpoint += 3, p1); |
1422 | par_shapes__add3(dpoint += 3, c); |
1423 | } |
1424 | PAR_FREE(mesh->points); |
1425 | mesh->points = points; |
1426 | mesh->npoints = npoints; |
1427 | mesh->ntriangles = ntriangles; |
1428 | } |
1429 | |
1430 | par_shapes_mesh* par_shapes_create_subdivided_sphere(int nsubd) |
1431 | { |
1432 | par_shapes_mesh* mesh = par_shapes_create_icosahedron(); |
1433 | par_shapes_unweld(mesh, false); |
1434 | PAR_FREE(mesh->triangles); |
1435 | mesh->triangles = 0; |
1436 | while (nsubd--) { |
1437 | par_shapes__subdivide(mesh); |
1438 | } |
1439 | for (int i = 0; i < mesh->npoints; i++) { |
1440 | par_shapes__normalize3(mesh->points + i * 3); |
1441 | } |
1442 | mesh->triangles = PAR_MALLOC(PAR_SHAPES_T, 3 * mesh->ntriangles); |
1443 | for (int i = 0; i < mesh->ntriangles * 3; i++) { |
1444 | mesh->triangles[i] = i; |
1445 | } |
1446 | par_shapes_mesh* tmp = mesh; |
1447 | mesh = par_shapes_weld(mesh, 0.01, 0); |
1448 | par_shapes_free_mesh(tmp); |
1449 | par_shapes_compute_normals(mesh); |
1450 | return mesh; |
1451 | } |
1452 | |
1453 | par_shapes_mesh* par_shapes_create_rock(int seed, int subd) |
1454 | { |
1455 | par_shapes_mesh* mesh = par_shapes_create_subdivided_sphere(subd); |
1456 | struct osn_context* ctx; |
1457 | par__simplex_noise(seed, &ctx); |
1458 | for (int p = 0; p < mesh->npoints; p++) { |
1459 | float* pt = mesh->points + p * 3; |
1460 | float a = 0.25, f = 1.0; |
1461 | double n = a * par__simplex_noise2(ctx, f * pt[0], f * pt[2]); |
1462 | a *= 0.5; f *= 2; |
1463 | n += a * par__simplex_noise2(ctx, f * pt[0], f * pt[2]); |
1464 | pt[0] *= 1 + 2 * n; |
1465 | pt[1] *= 1 + n; |
1466 | pt[2] *= 1 + 2 * n; |
1467 | if (pt[1] < 0) { |
1468 | pt[1] = -pow(-pt[1], 0.5) / 2; |
1469 | } |
1470 | } |
1471 | par__simplex_noise_free(ctx); |
1472 | par_shapes_compute_normals(mesh); |
1473 | return mesh; |
1474 | } |
1475 | |
1476 | par_shapes_mesh* par_shapes_clone(par_shapes_mesh const* mesh, |
1477 | par_shapes_mesh* clone) |
1478 | { |
1479 | if (!clone) { |
1480 | clone = PAR_CALLOC(par_shapes_mesh, 1); |
1481 | } |
1482 | clone->npoints = mesh->npoints; |
1483 | clone->points = PAR_REALLOC(float, clone->points, 3 * clone->npoints); |
1484 | memcpy(clone->points, mesh->points, sizeof(float) * 3 * clone->npoints); |
1485 | clone->ntriangles = mesh->ntriangles; |
1486 | clone->triangles = PAR_REALLOC(PAR_SHAPES_T, clone->triangles, 3 * |
1487 | clone->ntriangles); |
1488 | memcpy(clone->triangles, mesh->triangles, |
1489 | sizeof(PAR_SHAPES_T) * 3 * clone->ntriangles); |
1490 | if (mesh->normals) { |
1491 | clone->normals = PAR_REALLOC(float, clone->normals, 3 * clone->npoints); |
1492 | memcpy(clone->normals, mesh->normals, |
1493 | sizeof(float) * 3 * clone->npoints); |
1494 | } |
1495 | if (mesh->tcoords) { |
1496 | clone->tcoords = PAR_REALLOC(float, clone->tcoords, 2 * clone->npoints); |
1497 | memcpy(clone->tcoords, mesh->tcoords, |
1498 | sizeof(float) * 2 * clone->npoints); |
1499 | } |
1500 | return clone; |
1501 | } |
1502 | |
1503 | static struct { |
1504 | float const* points; |
1505 | int gridsize; |
1506 | } par_shapes__sort_context; |
1507 | |
1508 | static int par_shapes__cmp1(const void *arg0, const void *arg1) |
1509 | { |
1510 | const int g = par_shapes__sort_context.gridsize; |
1511 | |
1512 | // Convert arg0 into a flattened grid index. |
1513 | PAR_SHAPES_T d0 = *(const PAR_SHAPES_T*) arg0; |
1514 | float const* p0 = par_shapes__sort_context.points + d0 * 3; |
1515 | int i0 = (int) p0[0]; |
1516 | int j0 = (int) p0[1]; |
1517 | int k0 = (int) p0[2]; |
1518 | int index0 = i0 + g * j0 + g * g * k0; |
1519 | |
1520 | // Convert arg1 into a flattened grid index. |
1521 | PAR_SHAPES_T d1 = *(const PAR_SHAPES_T*) arg1; |
1522 | float const* p1 = par_shapes__sort_context.points + d1 * 3; |
1523 | int i1 = (int) p1[0]; |
1524 | int j1 = (int) p1[1]; |
1525 | int k1 = (int) p1[2]; |
1526 | int index1 = i1 + g * j1 + g * g * k1; |
1527 | |
1528 | // Return the ordering. |
1529 | if (index0 < index1) return -1; |
1530 | if (index0 > index1) return 1; |
1531 | return 0; |
1532 | } |
1533 | |
1534 | static void par_shapes__sort_points(par_shapes_mesh* mesh, int gridsize, |
1535 | PAR_SHAPES_T* sortmap) |
1536 | { |
1537 | // Run qsort over a list of consecutive integers that get deferenced |
1538 | // within the comparator function; this creates a reorder mapping. |
1539 | for (int i = 0; i < mesh->npoints; i++) { |
1540 | sortmap[i] = i; |
1541 | } |
1542 | par_shapes__sort_context.gridsize = gridsize; |
1543 | par_shapes__sort_context.points = mesh->points; |
1544 | qsort(sortmap, mesh->npoints, sizeof(PAR_SHAPES_T), par_shapes__cmp1); |
1545 | |
1546 | // Apply the reorder mapping to the XYZ coordinate data. |
1547 | float* newpts = PAR_MALLOC(float, mesh->npoints * 3); |
1548 | PAR_SHAPES_T* invmap = PAR_MALLOC(PAR_SHAPES_T, mesh->npoints); |
1549 | float* dstpt = newpts; |
1550 | for (int i = 0; i < mesh->npoints; i++) { |
1551 | invmap[sortmap[i]] = i; |
1552 | float const* srcpt = mesh->points + 3 * sortmap[i]; |
1553 | *dstpt++ = *srcpt++; |
1554 | *dstpt++ = *srcpt++; |
1555 | *dstpt++ = *srcpt++; |
1556 | } |
1557 | PAR_FREE(mesh->points); |
1558 | mesh->points = newpts; |
1559 | |
1560 | // Apply the inverse reorder mapping to the triangle indices. |
1561 | PAR_SHAPES_T* newinds = PAR_MALLOC(PAR_SHAPES_T, mesh->ntriangles * 3); |
1562 | PAR_SHAPES_T* dstind = newinds; |
1563 | PAR_SHAPES_T const* srcind = mesh->triangles; |
1564 | for (int i = 0; i < mesh->ntriangles * 3; i++) { |
1565 | *dstind++ = invmap[*srcind++]; |
1566 | } |
1567 | PAR_FREE(mesh->triangles); |
1568 | mesh->triangles = newinds; |
1569 | |
1570 | // Cleanup. |
1571 | memcpy(sortmap, invmap, sizeof(PAR_SHAPES_T) * mesh->npoints); |
1572 | PAR_FREE(invmap); |
1573 | } |
1574 | |
1575 | static void par_shapes__weld_points(par_shapes_mesh* mesh, int gridsize, |
1576 | float epsilon, PAR_SHAPES_T* weldmap) |
1577 | { |
1578 | // Each bin contains a "pointer" (really an index) to its first point. |
1579 | // We add 1 because 0 is reserved to mean that the bin is empty. |
1580 | // Since the points are spatially sorted, there's no need to store |
1581 | // a point count in each bin. |
1582 | PAR_SHAPES_T* bins = PAR_CALLOC(PAR_SHAPES_T, |
1583 | gridsize * gridsize * gridsize); |
1584 | int prev_binindex = -1; |
1585 | for (int p = 0; p < mesh->npoints; p++) { |
1586 | float const* pt = mesh->points + p * 3; |
1587 | int i = (int) pt[0]; |
1588 | int j = (int) pt[1]; |
1589 | int k = (int) pt[2]; |
1590 | int this_binindex = i + gridsize * j + gridsize * gridsize * k; |
1591 | if (this_binindex != prev_binindex) { |
1592 | bins[this_binindex] = 1 + p; |
1593 | } |
1594 | prev_binindex = this_binindex; |
1595 | } |
1596 | |
1597 | // Examine all bins that intersect the epsilon-sized cube centered at each |
1598 | // point, and check for colocated points within those bins. |
1599 | float const* pt = mesh->points; |
1600 | int nremoved = 0; |
1601 | for (int p = 0; p < mesh->npoints; p++, pt += 3) { |
1602 | |
1603 | // Skip if this point has already been welded. |
1604 | if (weldmap[p] != p) { |
1605 | continue; |
1606 | } |
1607 | |
1608 | // Build a list of bins that intersect the epsilon-sized cube. |
1609 | int nearby[8]; |
1610 | int nbins = 0; |
1611 | int minp[3], maxp[3]; |
1612 | for (int c = 0; c < 3; c++) { |
1613 | minp[c] = (int) (pt[c] - epsilon); |
1614 | maxp[c] = (int) (pt[c] + epsilon); |
1615 | } |
1616 | for (int i = minp[0]; i <= maxp[0]; i++) { |
1617 | for (int j = minp[1]; j <= maxp[1]; j++) { |
1618 | for (int k = minp[2]; k <= maxp[2]; k++) { |
1619 | int binindex = i + gridsize * j + gridsize * gridsize * k; |
1620 | PAR_SHAPES_T binvalue = *(bins + binindex); |
1621 | if (binvalue > 0) { |
1622 | if (nbins == 8) { |
1623 | //printf("Epsilon value is too large.\n"); |
1624 | break; |
1625 | } |
1626 | nearby[nbins++] = binindex; |
1627 | } |
1628 | } |
1629 | } |
1630 | } |
1631 | |
1632 | // Check for colocated points in each nearby bin. |
1633 | for (int b = 0; b < nbins; b++) { |
1634 | int binindex = nearby[b]; |
1635 | PAR_SHAPES_T binvalue = *(bins + binindex); |
1636 | PAR_SHAPES_T nindex = binvalue - 1; |
1637 | while (true) { |
1638 | |
1639 | // If this isn't "self" and it's colocated, then weld it! |
1640 | if (nindex != p && weldmap[nindex] == nindex) { |
1641 | float const* thatpt = mesh->points + nindex * 3; |
1642 | float dist2 = par_shapes__sqrdist3(thatpt, pt); |
1643 | if (dist2 < epsilon) { |
1644 | weldmap[nindex] = p; |
1645 | nremoved++; |
1646 | } |
1647 | } |
1648 | |
1649 | // Advance to the next point if possible. |
1650 | if (++nindex >= mesh->npoints) { |
1651 | break; |
1652 | } |
1653 | |
1654 | // If the next point is outside the bin, then we're done. |
1655 | float const* nextpt = mesh->points + nindex * 3; |
1656 | int i = (int) nextpt[0]; |
1657 | int j = (int) nextpt[1]; |
1658 | int k = (int) nextpt[2]; |
1659 | int nextbinindex = i + gridsize * j + gridsize * gridsize * k; |
1660 | if (nextbinindex != binindex) { |
1661 | break; |
1662 | } |
1663 | } |
1664 | } |
1665 | } |
1666 | PAR_FREE(bins); |
1667 | |
1668 | // Apply the weldmap to the vertices. |
1669 | int npoints = mesh->npoints - nremoved; |
1670 | float* newpts = PAR_MALLOC(float, 3 * npoints); |
1671 | float* dst = newpts; |
1672 | PAR_SHAPES_T* condensed_map = PAR_MALLOC(PAR_SHAPES_T, mesh->npoints); |
1673 | PAR_SHAPES_T* cmap = condensed_map; |
1674 | float const* src = mesh->points; |
1675 | int ci = 0; |
1676 | for (int p = 0; p < mesh->npoints; p++, src += 3) { |
1677 | if (weldmap[p] == p) { |
1678 | *dst++ = src[0]; |
1679 | *dst++ = src[1]; |
1680 | *dst++ = src[2]; |
1681 | *cmap++ = ci++; |
1682 | } else { |
1683 | *cmap++ = condensed_map[weldmap[p]]; |
1684 | } |
1685 | } |
1686 | assert(ci == npoints); |
1687 | PAR_FREE(mesh->points); |
1688 | memcpy(weldmap, condensed_map, mesh->npoints * sizeof(PAR_SHAPES_T)); |
1689 | PAR_FREE(condensed_map); |
1690 | mesh->points = newpts; |
1691 | mesh->npoints = npoints; |
1692 | |
1693 | // Apply the weldmap to the triangle indices and skip the degenerates. |
1694 | PAR_SHAPES_T const* tsrc = mesh->triangles; |
1695 | PAR_SHAPES_T* tdst = mesh->triangles; |
1696 | int ntriangles = 0; |
1697 | for (int i = 0; i < mesh->ntriangles; i++, tsrc += 3) { |
1698 | PAR_SHAPES_T a = weldmap[tsrc[0]]; |
1699 | PAR_SHAPES_T b = weldmap[tsrc[1]]; |
1700 | PAR_SHAPES_T c = weldmap[tsrc[2]]; |
1701 | if (a != b && a != c && b != c) { |
1702 | *tdst++ = a; |
1703 | *tdst++ = b; |
1704 | *tdst++ = c; |
1705 | ntriangles++; |
1706 | } |
1707 | } |
1708 | mesh->ntriangles = ntriangles; |
1709 | } |
1710 | |
1711 | par_shapes_mesh* par_shapes_weld(par_shapes_mesh const* mesh, float epsilon, |
1712 | PAR_SHAPES_T* weldmap) |
1713 | { |
1714 | par_shapes_mesh* clone = par_shapes_clone(mesh, 0); |
1715 | float aabb[6]; |
1716 | int gridsize = 20; |
1717 | float maxcell = gridsize - 1; |
1718 | par_shapes_compute_aabb(clone, aabb); |
1719 | float scale[3] = { |
1720 | aabb[3] == aabb[0] ? 1.0f : maxcell / (aabb[3] - aabb[0]), |
1721 | aabb[4] == aabb[1] ? 1.0f : maxcell / (aabb[4] - aabb[1]), |
1722 | aabb[5] == aabb[2] ? 1.0f : maxcell / (aabb[5] - aabb[2]), |
1723 | }; |
1724 | par_shapes_translate(clone, -aabb[0], -aabb[1], -aabb[2]); |
1725 | par_shapes_scale(clone, scale[0], scale[1], scale[2]); |
1726 | PAR_SHAPES_T* sortmap = PAR_MALLOC(PAR_SHAPES_T, mesh->npoints); |
1727 | par_shapes__sort_points(clone, gridsize, sortmap); |
1728 | bool owner = false; |
1729 | if (!weldmap) { |
1730 | owner = true; |
1731 | weldmap = PAR_MALLOC(PAR_SHAPES_T, mesh->npoints); |
1732 | } |
1733 | for (int i = 0; i < mesh->npoints; i++) { |
1734 | weldmap[i] = i; |
1735 | } |
1736 | par_shapes__weld_points(clone, gridsize, epsilon, weldmap); |
1737 | if (owner) { |
1738 | PAR_FREE(weldmap); |
1739 | } else { |
1740 | PAR_SHAPES_T* newmap = PAR_MALLOC(PAR_SHAPES_T, mesh->npoints); |
1741 | for (int i = 0; i < mesh->npoints; i++) { |
1742 | newmap[i] = weldmap[sortmap[i]]; |
1743 | } |
1744 | memcpy(weldmap, newmap, sizeof(PAR_SHAPES_T) * mesh->npoints); |
1745 | PAR_FREE(newmap); |
1746 | } |
1747 | PAR_FREE(sortmap); |
1748 | par_shapes_scale(clone, 1.0 / scale[0], 1.0 / scale[1], 1.0 / scale[2]); |
1749 | par_shapes_translate(clone, aabb[0], aabb[1], aabb[2]); |
1750 | return clone; |
1751 | } |
1752 | |
1753 | // ----------------------------------------------------------------------------- |
1754 | // BEGIN OPEN SIMPLEX NOISE |
1755 | // ----------------------------------------------------------------------------- |
1756 | |
1757 | #define STRETCH_CONSTANT_2D (-0.211324865405187) // (1 / sqrt(2 + 1) - 1 ) / 2; |
1758 | #define SQUISH_CONSTANT_2D (0.366025403784439) // (sqrt(2 + 1) -1) / 2; |
1759 | #define STRETCH_CONSTANT_3D (-1.0 / 6.0) // (1 / sqrt(3 + 1) - 1) / 3; |
1760 | #define SQUISH_CONSTANT_3D (1.0 / 3.0) // (sqrt(3+1)-1)/3; |
1761 | #define STRETCH_CONSTANT_4D (-0.138196601125011) // (1 / sqrt(4 + 1) - 1) / 4; |
1762 | #define SQUISH_CONSTANT_4D (0.309016994374947) // (sqrt(4 + 1) - 1) / 4; |
1763 | |
1764 | #define NORM_CONSTANT_2D (47.0) |
1765 | #define NORM_CONSTANT_3D (103.0) |
1766 | #define NORM_CONSTANT_4D (30.0) |
1767 | |
1768 | #define DEFAULT_SEED (0LL) |
1769 | |
1770 | struct osn_context { |
1771 | int16_t* perm; |
1772 | int16_t* permGradIndex3D; |
1773 | }; |
1774 | |
1775 | #define ARRAYSIZE(x) (sizeof((x)) / sizeof((x)[0])) |
1776 | |
1777 | /* |
1778 | * Gradients for 2D. They approximate the directions to the |
1779 | * vertices of an octagon from the center. |
1780 | */ |
1781 | static const int8_t gradients2D[] = { |
1782 | 5, 2, 2, 5, -5, 2, -2, 5, 5, -2, 2, -5, -5, -2, -2, -5, |
1783 | }; |
1784 | |
1785 | /* |
1786 | * Gradients for 3D. They approximate the directions to the |
1787 | * vertices of a rhombicuboctahedron from the center, skewed so |
1788 | * that the triangular and square facets can be inscribed inside |
1789 | * circles of the same radius. |
1790 | */ |
1791 | static const signed char gradients3D[] = { |
1792 | -11, 4, 4, -4, 11, 4, -4, 4, 11, 11, 4, 4, 4, 11, 4, 4, 4, 11, -11, -4, 4, |
1793 | -4, -11, 4, -4, -4, 11, 11, -4, 4, 4, -11, 4, 4, -4, 11, -11, 4, -4, -4, 11, |
1794 | -4, -4, 4, -11, 11, 4, -4, 4, 11, -4, 4, 4, -11, -11, -4, -4, -4, -11, -4, |
1795 | -4, -4, -11, 11, -4, -4, 4, -11, -4, 4, -4, -11, |
1796 | }; |
1797 | |
1798 | /* |
1799 | * Gradients for 4D. They approximate the directions to the |
1800 | * vertices of a disprismatotesseractihexadecachoron from the center, |
1801 | * skewed so that the tetrahedral and cubic facets can be inscribed inside |
1802 | * spheres of the same radius. |
1803 | */ |
1804 | static const signed char gradients4D[] = { |
1805 | 3, 1, 1, 1, 1, 3, 1, 1, 1, 1, 3, 1, 1, 1, 1, 3, -3, 1, 1, 1, -1, 3, 1, 1, |
1806 | -1, 1, 3, 1, -1, 1, 1, 3, 3, -1, 1, 1, 1, -3, 1, 1, 1, -1, 3, 1, 1, -1, 1, |
1807 | 3, -3, -1, 1, 1, -1, -3, 1, 1, -1, -1, 3, 1, -1, -1, 1, 3, 3, 1, -1, 1, 1, |
1808 | 3, -1, 1, 1, 1, -3, 1, 1, 1, -1, 3, -3, 1, -1, 1, -1, 3, -1, 1, -1, 1, -3, |
1809 | 1, -1, 1, -1, 3, 3, -1, -1, 1, 1, -3, -1, 1, 1, -1, -3, 1, 1, -1, -1, 3, -3, |
1810 | -1, -1, 1, -1, -3, -1, 1, -1, -1, -3, 1, -1, -1, -1, 3, 3, 1, 1, -1, 1, 3, |
1811 | 1, -1, 1, 1, 3, -1, 1, 1, 1, -3, -3, 1, 1, -1, -1, 3, 1, -1, -1, 1, 3, -1, |
1812 | -1, 1, 1, -3, 3, -1, 1, -1, 1, -3, 1, -1, 1, -1, 3, -1, 1, -1, 1, -3, -3, |
1813 | -1, 1, -1, -1, -3, 1, -1, -1, -1, 3, -1, -1, -1, 1, -3, 3, 1, -1, -1, 1, 3, |
1814 | -1, -1, 1, 1, -3, -1, 1, 1, -1, -3, -3, 1, -1, -1, -1, 3, -1, -1, -1, 1, -3, |
1815 | -1, -1, 1, -1, -3, 3, -1, -1, -1, 1, -3, -1, -1, 1, -1, -3, -1, 1, -1, -1, |
1816 | -3, -3, -1, -1, -1, -1, -3, -1, -1, -1, -1, -3, -1, -1, -1, -1, -3, |
1817 | }; |
1818 | |
1819 | static double ( |
1820 | struct osn_context* ctx, int xsb, int ysb, double dx, double dy) |
1821 | { |
1822 | int16_t* perm = ctx->perm; |
1823 | int index = perm[(perm[xsb & 0xFF] + ysb) & 0xFF] & 0x0E; |
1824 | return gradients2D[index] * dx + gradients2D[index + 1] * dy; |
1825 | } |
1826 | |
1827 | static inline int fastFloor(double x) |
1828 | { |
1829 | int xi = (int) x; |
1830 | return x < xi ? xi - 1 : xi; |
1831 | } |
1832 | |
1833 | static int allocate_perm(struct osn_context* ctx, int nperm, int ngrad) |
1834 | { |
1835 | PAR_FREE(ctx->perm); |
1836 | PAR_FREE(ctx->permGradIndex3D); |
1837 | ctx->perm = PAR_MALLOC(int16_t, nperm); |
1838 | if (!ctx->perm) { |
1839 | return -ENOMEM; |
1840 | } |
1841 | ctx->permGradIndex3D = PAR_MALLOC(int16_t, ngrad); |
1842 | if (!ctx->permGradIndex3D) { |
1843 | PAR_FREE(ctx->perm); |
1844 | return -ENOMEM; |
1845 | } |
1846 | return 0; |
1847 | } |
1848 | |
1849 | static int par__simplex_noise(int64_t seed, struct osn_context** ctx) |
1850 | { |
1851 | int rc; |
1852 | int16_t source[256]; |
1853 | int i; |
1854 | int16_t* perm; |
1855 | int16_t* permGradIndex3D; |
1856 | *ctx = PAR_MALLOC(struct osn_context, 1); |
1857 | if (!(*ctx)) { |
1858 | return -ENOMEM; |
1859 | } |
1860 | (*ctx)->perm = NULL; |
1861 | (*ctx)->permGradIndex3D = NULL; |
1862 | rc = allocate_perm(*ctx, 256, 256); |
1863 | if (rc) { |
1864 | PAR_FREE(*ctx); |
1865 | return rc; |
1866 | } |
1867 | perm = (*ctx)->perm; |
1868 | permGradIndex3D = (*ctx)->permGradIndex3D; |
1869 | for (i = 0; i < 256; i++) { |
1870 | source[i] = (int16_t) i; |
1871 | } |
1872 | seed = seed * 6364136223846793005LL + 1442695040888963407LL; |
1873 | seed = seed * 6364136223846793005LL + 1442695040888963407LL; |
1874 | seed = seed * 6364136223846793005LL + 1442695040888963407LL; |
1875 | for (i = 255; i >= 0; i--) { |
1876 | seed = seed * 6364136223846793005LL + 1442695040888963407LL; |
1877 | int r = (int) ((seed + 31) % (i + 1)); |
1878 | if (r < 0) |
1879 | r += (i + 1); |
1880 | perm[i] = source[r]; |
1881 | permGradIndex3D[i] = |
1882 | (short) ((perm[i] % (ARRAYSIZE(gradients3D) / 3)) * 3); |
1883 | source[r] = source[i]; |
1884 | } |
1885 | return 0; |
1886 | } |
1887 | |
1888 | static void par__simplex_noise_free(struct osn_context* ctx) |
1889 | { |
1890 | if (!ctx) |
1891 | return; |
1892 | if (ctx->perm) { |
1893 | PAR_FREE(ctx->perm); |
1894 | ctx->perm = NULL; |
1895 | } |
1896 | if (ctx->permGradIndex3D) { |
1897 | PAR_FREE(ctx->permGradIndex3D); |
1898 | ctx->permGradIndex3D = NULL; |
1899 | } |
1900 | PAR_FREE(ctx); |
1901 | } |
1902 | |
1903 | static double par__simplex_noise2(struct osn_context* ctx, double x, double y) |
1904 | { |
1905 | // Place input coordinates onto grid. |
1906 | double stretchOffset = (x + y) * STRETCH_CONSTANT_2D; |
1907 | double xs = x + stretchOffset; |
1908 | double ys = y + stretchOffset; |
1909 | |
1910 | // Floor to get grid coordinates of rhombus (stretched square) super-cell |
1911 | // origin. |
1912 | int xsb = fastFloor(xs); |
1913 | int ysb = fastFloor(ys); |
1914 | |
1915 | // Skew out to get actual coordinates of rhombus origin. We'll need these |
1916 | // later. |
1917 | double squishOffset = (xsb + ysb) * SQUISH_CONSTANT_2D; |
1918 | double xb = xsb + squishOffset; |
1919 | double yb = ysb + squishOffset; |
1920 | |
1921 | // Compute grid coordinates relative to rhombus origin. |
1922 | double xins = xs - xsb; |
1923 | double yins = ys - ysb; |
1924 | |
1925 | // Sum those together to get a value that determines which region we're in. |
1926 | double inSum = xins + yins; |
1927 | |
1928 | // Positions relative to origin point. |
1929 | double dx0 = x - xb; |
1930 | double dy0 = y - yb; |
1931 | |
1932 | // We'll be defining these inside the next block and using them afterwards. |
1933 | double dx_ext, dy_ext; |
1934 | int xsv_ext, ysv_ext; |
1935 | |
1936 | double value = 0; |
1937 | |
1938 | // Contribution (1,0) |
1939 | double dx1 = dx0 - 1 - SQUISH_CONSTANT_2D; |
1940 | double dy1 = dy0 - 0 - SQUISH_CONSTANT_2D; |
1941 | double attn1 = 2 - dx1 * dx1 - dy1 * dy1; |
1942 | if (attn1 > 0) { |
1943 | attn1 *= attn1; |
1944 | value += attn1 * attn1 * extrapolate2(ctx, xsb + 1, ysb + 0, dx1, dy1); |
1945 | } |
1946 | |
1947 | // Contribution (0,1) |
1948 | double dx2 = dx0 - 0 - SQUISH_CONSTANT_2D; |
1949 | double dy2 = dy0 - 1 - SQUISH_CONSTANT_2D; |
1950 | double attn2 = 2 - dx2 * dx2 - dy2 * dy2; |
1951 | if (attn2 > 0) { |
1952 | attn2 *= attn2; |
1953 | value += attn2 * attn2 * extrapolate2(ctx, xsb + 0, ysb + 1, dx2, dy2); |
1954 | } |
1955 | |
1956 | if (inSum <= 1) { // We're inside the triangle (2-Simplex) at (0,0) |
1957 | double zins = 1 - inSum; |
1958 | if (zins > xins || zins > yins) { |
1959 | if (xins > yins) { |
1960 | xsv_ext = xsb + 1; |
1961 | ysv_ext = ysb - 1; |
1962 | dx_ext = dx0 - 1; |
1963 | dy_ext = dy0 + 1; |
1964 | } else { |
1965 | xsv_ext = xsb - 1; |
1966 | ysv_ext = ysb + 1; |
1967 | dx_ext = dx0 + 1; |
1968 | dy_ext = dy0 - 1; |
1969 | } |
1970 | } else { //(1,0) and (0,1) are the closest two vertices. |
1971 | xsv_ext = xsb + 1; |
1972 | ysv_ext = ysb + 1; |
1973 | dx_ext = dx0 - 1 - 2 * SQUISH_CONSTANT_2D; |
1974 | dy_ext = dy0 - 1 - 2 * SQUISH_CONSTANT_2D; |
1975 | } |
1976 | } else { // We're inside the triangle (2-Simplex) at (1,1) |
1977 | double zins = 2 - inSum; |
1978 | if (zins < xins || zins < yins) { |
1979 | if (xins > yins) { |
1980 | xsv_ext = xsb + 2; |
1981 | ysv_ext = ysb + 0; |
1982 | dx_ext = dx0 - 2 - 2 * SQUISH_CONSTANT_2D; |
1983 | dy_ext = dy0 + 0 - 2 * SQUISH_CONSTANT_2D; |
1984 | } else { |
1985 | xsv_ext = xsb + 0; |
1986 | ysv_ext = ysb + 2; |
1987 | dx_ext = dx0 + 0 - 2 * SQUISH_CONSTANT_2D; |
1988 | dy_ext = dy0 - 2 - 2 * SQUISH_CONSTANT_2D; |
1989 | } |
1990 | } else { //(1,0) and (0,1) are the closest two vertices. |
1991 | dx_ext = dx0; |
1992 | dy_ext = dy0; |
1993 | xsv_ext = xsb; |
1994 | ysv_ext = ysb; |
1995 | } |
1996 | xsb += 1; |
1997 | ysb += 1; |
1998 | dx0 = dx0 - 1 - 2 * SQUISH_CONSTANT_2D; |
1999 | dy0 = dy0 - 1 - 2 * SQUISH_CONSTANT_2D; |
2000 | } |
2001 | |
2002 | // Contribution (0,0) or (1,1) |
2003 | double attn0 = 2 - dx0 * dx0 - dy0 * dy0; |
2004 | if (attn0 > 0) { |
2005 | attn0 *= attn0; |
2006 | value += attn0 * attn0 * extrapolate2(ctx, xsb, ysb, dx0, dy0); |
2007 | } |
2008 | |
2009 | // Extra Vertex |
2010 | double attn_ext = 2 - dx_ext * dx_ext - dy_ext * dy_ext; |
2011 | if (attn_ext > 0) { |
2012 | attn_ext *= attn_ext; |
2013 | value += attn_ext * attn_ext * |
2014 | extrapolate2(ctx, xsv_ext, ysv_ext, dx_ext, dy_ext); |
2015 | } |
2016 | |
2017 | return value / NORM_CONSTANT_2D; |
2018 | } |
2019 | |
2020 | void par_shapes_remove_degenerate(par_shapes_mesh* mesh, float mintriarea) |
2021 | { |
2022 | int ntriangles = 0; |
2023 | PAR_SHAPES_T* triangles = PAR_MALLOC(PAR_SHAPES_T, mesh->ntriangles * 3); |
2024 | PAR_SHAPES_T* dst = triangles; |
2025 | PAR_SHAPES_T const* src = mesh->triangles; |
2026 | float next[3], prev[3], cp[3]; |
2027 | float mincplen2 = (mintriarea * 2) * (mintriarea * 2); |
2028 | for (int f = 0; f < mesh->ntriangles; f++, src += 3) { |
2029 | float const* pa = mesh->points + 3 * src[0]; |
2030 | float const* pb = mesh->points + 3 * src[1]; |
2031 | float const* pc = mesh->points + 3 * src[2]; |
2032 | par_shapes__copy3(next, pb); |
2033 | par_shapes__subtract3(next, pa); |
2034 | par_shapes__copy3(prev, pc); |
2035 | par_shapes__subtract3(prev, pa); |
2036 | par_shapes__cross3(cp, next, prev); |
2037 | float cplen2 = par_shapes__dot3(cp, cp); |
2038 | if (cplen2 >= mincplen2) { |
2039 | *dst++ = src[0]; |
2040 | *dst++ = src[1]; |
2041 | *dst++ = src[2]; |
2042 | ntriangles++; |
2043 | } |
2044 | } |
2045 | mesh->ntriangles = ntriangles; |
2046 | PAR_FREE(mesh->triangles); |
2047 | mesh->triangles = triangles; |
2048 | } |
2049 | |
2050 | #endif // PAR_SHAPES_IMPLEMENTATION |
2051 | #endif // PAR_SHAPES_H |
2052 | |