a fairly major physics update
[carveJwlIkooP6JGAAIwe30JlM.git] / scene.h
1 #ifndef SCENE_H
2 #define SCENE_H
3
4 #include "common.h"
5 #include "model.h"
6 #include "bvh.h"
7
8 typedef struct scene scene;
9
10 struct scene
11 {
12 mdl_vert *arrvertices;
13 u32 *arrindices;
14
15 u32 vertex_count, indice_count,
16 max_vertices, max_indices;
17
18 boxf bbx;
19 mdl_submesh submesh;
20 };
21
22 /* Initialize a scene description with bounded buffers */
23 VG_STATIC scene *scene_init( void *lin_alloc, u32 max_verts, u32 max_indices )
24 {
25 u32 vertex_length = max_verts * sizeof(mdl_vert),
26 index_length = max_indices * sizeof(u32),
27 tot_size = sizeof(scene) + vertex_length + index_length;
28
29 scene *pscene = vg_linear_alloc( lin_alloc, tot_size );
30
31 pscene->arrvertices = (mdl_vert *)(pscene+1);
32 pscene->arrindices = (u32 *)( pscene->arrvertices + max_verts );
33
34 pscene->vertex_count = 0;
35 pscene->indice_count = 0;
36 pscene->max_vertices = max_verts;
37 pscene->max_indices = max_indices;
38
39 memset( &pscene->submesh, 0, sizeof(mdl_submesh) );
40
41 v3_fill( pscene->bbx[0], 999999.9f );
42 v3_fill( pscene->bbx[1], -999999.9f );
43
44 return pscene;
45 }
46
47 /*
48 * Append a model into the scene with a given transform
49 */
50 VG_STATIC void scene_add_submesh( scene *pscene, mdl_context *mdl,
51 mdl_submesh *sm, m4x3f transform )
52 {
53 if( pscene->vertex_count + sm->vertex_count > pscene->max_vertices )
54 {
55 vg_error( "%u(current) + %u > %u\n", pscene->vertex_count,
56 sm->vertex_count,
57 pscene->max_vertices );
58
59 vg_warn( "%p ... %p\n", pscene, sm );
60 vg_fatal_exit_loop( "Scene vertex buffer overflow" );
61 }
62
63 if( pscene->indice_count + sm->indice_count > pscene->max_indices )
64 {
65 vg_error( "%u(current) + %u > %u\n", pscene->indice_count,
66 sm->indice_count,
67 pscene->max_indices );
68 vg_warn( "%p ... %p\n", pscene, sm );
69
70 vg_fatal_exit_loop( "Scene index buffer overflow" );
71 }
72
73 mdl_vert *src_verts = mdl_submesh_vertices( mdl, sm ),
74 *dst_verts = &pscene->arrvertices[ pscene->vertex_count ];
75
76 u32 *src_indices = mdl_submesh_indices( mdl, sm ),
77 *dst_indices = &pscene->arrindices[ pscene->indice_count ];
78
79 /* Transform and place vertices */
80 boxf bbxnew;
81 box_copy( sm->bbx, bbxnew );
82 m4x3_transform_aabb( transform, bbxnew );
83 box_concat( pscene->bbx, bbxnew );
84
85 m3x3f normal_matrix;
86 m3x3_copy( transform, normal_matrix );
87 v3_normalize( normal_matrix[0] );
88 v3_normalize( normal_matrix[1] );
89 v3_normalize( normal_matrix[2] );
90
91 for( u32 i=0; i<sm->vertex_count; i++ )
92 {
93 mdl_vert *pvert = &dst_verts[ i ],
94 *src = &src_verts[ i ];
95
96 m4x3_mulv( transform, src->co, pvert->co );
97 m3x3_mulv( normal_matrix, src->norm, pvert->norm );
98
99 pvert->colour[0] = src->colour[0];
100 pvert->colour[1] = src->colour[1];
101 pvert->colour[2] = src->colour[2];
102 pvert->colour[3] = src->colour[3];
103 pvert->weights[0] = src->weights[0];
104 pvert->weights[1] = src->weights[1];
105 pvert->weights[2] = src->weights[2];
106 pvert->weights[3] = src->weights[3];
107 v2_copy( src->uv, pvert->uv );
108 }
109
110 for( u32 i=0; i<sm->indice_count; i++ )
111 {
112 dst_indices[i] = src_indices[i] + pscene->vertex_count;
113 }
114
115 pscene->vertex_count += sm->vertex_count;
116 pscene->indice_count += sm->indice_count;
117
118 }
119
120 /*
121 * One by one adders for simplified access (mostly procedural stuff)
122 */
123 VG_STATIC void scene_push_tri( scene *pscene, u32 tri[3] )
124 {
125 if( pscene->indice_count + 3 > pscene->max_indices )
126 vg_fatal_exit_loop( "Scene vertex buffer overflow" );
127
128 u32 *dst = &pscene->arrindices[ pscene->indice_count ];
129
130 dst[0] = tri[0];
131 dst[1] = tri[1];
132 dst[2] = tri[2];
133
134 pscene->indice_count += 3;
135 }
136
137 VG_STATIC void scene_push_vert( scene *pscene, mdl_vert *v )
138 {
139 if( pscene->vertex_count + 1 > pscene->max_vertices )
140 vg_fatal_exit_loop( "Scene vertex buffer overflow" );
141
142 mdl_vert *dst = &pscene->arrvertices[ pscene->vertex_count ];
143 *dst = *v;
144
145 pscene->vertex_count ++;
146 }
147
148 VG_STATIC void scene_copy_slice( scene *pscene, mdl_submesh *sm )
149 {
150 sm->indice_start = pscene->submesh.indice_start;
151 sm->indice_count = pscene->indice_count - sm->indice_start;
152
153 sm->vertex_start = pscene->submesh.vertex_start;
154 sm->vertex_count = pscene->vertex_count - sm->vertex_start;
155
156 pscene->submesh.indice_start = pscene->indice_count;
157 pscene->submesh.vertex_start = pscene->vertex_count;
158 }
159
160 /* finalization: tightly pack data */
161 __attribute__((warn_unused_result))
162 VG_STATIC scene *scene_fix( void *lin_alloc, scene *pscene )
163 {
164 return pscene;
165 u32 vertex_count = pscene->vertex_count,
166 indice_count = pscene->indice_count,
167 vertex_length = vertex_count * sizeof(mdl_vert),
168 index_length = indice_count * sizeof(u32),
169 tot_size = sizeof(scene) + vertex_length + index_length;
170
171 /* copy down index data */
172 void *dst_indices = pscene->arrvertices + vertex_length;
173 memmove( dst_indices, pscene->arrindices, index_length );
174
175 /* realloc */
176 pscene = vg_linear_resize( lin_alloc, pscene, tot_size );
177
178 pscene->arrvertices = (mdl_vert *)(pscene+1);
179 pscene->arrindices = (u32 *)(pscene->arrvertices+vertex_count);
180 pscene->max_vertices = vertex_count;
181 pscene->max_indices = indice_count;
182
183 return pscene;
184 }
185
186 #if 0
187 /* finalization: delete any offline buffers and reduce size */
188 __attribute__((warn_unused_result))
189 VG_STATIC scene *scene_free_offline_buffers( void *lin_alloc, scene *pscene )
190 {
191 u32 tot_size = sizeof(scene);
192
193 scene *src_scene = pscene;
194 mdl_vert *src_verts = pscene->arrvertices;
195 u32 *src_indices = pscene->arrindices;
196
197 scene *dst_scene = vg_linear_resize( lin_alloc, pscene, tot_size );
198 memcpy( dst_scene, src_scene, sizeof(scene) );
199
200 dst_scene->arrindices = NULL;
201 dst_scene->arrvertices = NULL;
202
203 return dst_scene;
204 }
205 #endif
206
207 VG_STATIC void scene_upload( scene *pscene, glmesh *mesh )
208 {
209 mesh_upload( mesh,
210 pscene->arrvertices, pscene->vertex_count,
211 pscene->arrindices, pscene->indice_count );
212
213 vg_info( "Scene upload\n" );
214 vg_info( " indices:%u\n", pscene->indice_count );
215 vg_info( " verts:%u\n", pscene->vertex_count );
216 }
217
218 /*
219 * BVH implementation
220 */
221
222 VG_STATIC void scene_bh_expand_bound( void *user, boxf bound, u32 item_index )
223 {
224 scene *s = user;
225 mdl_vert *pa = &s->arrvertices[ s->arrindices[item_index*3+0] ],
226 *pb = &s->arrvertices[ s->arrindices[item_index*3+1] ],
227 *pc = &s->arrvertices[ s->arrindices[item_index*3+2] ];
228
229 box_addpt( bound, pa->co );
230 box_addpt( bound, pb->co );
231 box_addpt( bound, pc->co );
232 }
233
234 VG_STATIC float scene_bh_centroid( void *user, u32 item_index, int axis )
235 {
236 scene *s = user;
237 mdl_vert *pa = &s->arrvertices[ s->arrindices[item_index*3+0] ],
238 *pb = &s->arrvertices[ s->arrindices[item_index*3+1] ],
239 *pc = &s->arrvertices[ s->arrindices[item_index*3+2] ];
240
241 return (pa->co[axis] + pb->co[axis] + pc->co[axis]) * (1.0f/3.0f);
242 }
243
244 VG_STATIC void scene_bh_swap( void *user, u32 ia, u32 ib )
245 {
246 scene *s = user;
247
248 u32 *ti = &s->arrindices[ia*3];
249 u32 *tj = &s->arrindices[ib*3];
250
251 u32 temp[3];
252 temp[0] = ti[0];
253 temp[1] = ti[1];
254 temp[2] = ti[2];
255
256 ti[0] = tj[0];
257 ti[1] = tj[1];
258 ti[2] = tj[2];
259
260 tj[0] = temp[0];
261 tj[1] = temp[1];
262 tj[2] = temp[2];
263 }
264
265 VG_STATIC void scene_bh_debug( void *user, u32 item_index )
266 {
267 scene *s = user;
268 u32 idx = item_index*3;
269 mdl_vert *pa = &s->arrvertices[ s->arrindices[ idx+0 ] ],
270 *pb = &s->arrvertices[ s->arrindices[ idx+1 ] ],
271 *pc = &s->arrvertices[ s->arrindices[ idx+2 ] ];
272
273 vg_line( pa->co, pb->co, 0xff0000ff );
274 vg_line( pb->co, pc->co, 0xff0000ff );
275 vg_line( pc->co, pa->co, 0xff0000ff );
276 }
277
278 VG_STATIC int scene_bh_ray( void *user, u32 index, v3f co,
279 v3f dir, ray_hit *hit )
280 {
281 scene *s = user;
282 v3f positions[3];
283
284 u32 *tri = &s->arrindices[ index*3 ];
285
286 for( int i=0; i<3; i++ )
287 v3_copy( s->arrvertices[tri[i]].co, positions[i] );
288
289 float t;
290 if(ray_tri( positions, co, dir, &t ))
291 {
292 if( t < hit->dist )
293 {
294 hit->dist = t;
295 hit->tri = tri;
296 return 1;
297 }
298 }
299
300 return 0;
301 }
302
303 VG_STATIC void scene_bh_closest( void *user, u32 index, v3f point, v3f closest )
304 {
305 scene *s = user;
306
307 v3f positions[3];
308 u32 *tri = &s->arrindices[ index*3 ];
309 for( int i=0; i<3; i++ )
310 v3_copy( s->arrvertices[tri[i]].co, positions[i] );
311
312 closest_on_triangle_1( point, positions, closest );
313 }
314
315 VG_STATIC bh_system bh_system_scene =
316 {
317 .expand_bound = scene_bh_expand_bound,
318 .item_centroid = scene_bh_centroid,
319 .item_closest = scene_bh_closest,
320 .item_swap = scene_bh_swap,
321 .item_debug = scene_bh_debug,
322 .cast_ray = scene_bh_ray
323 };
324
325 /*
326 * An extra step is added onto the end to calculate the hit normal
327 */
328 VG_STATIC int scene_raycast( scene *s, bh_tree *bh,
329 v3f co, v3f dir, ray_hit *hit )
330 {
331 int count = bh_ray( bh, co, dir, hit );
332
333 if( count )
334 {
335 v3f v0, v1;
336
337 float *pa = s->arrvertices[hit->tri[0]].co,
338 *pb = s->arrvertices[hit->tri[1]].co,
339 *pc = s->arrvertices[hit->tri[2]].co;
340
341 v3_sub( pa, pb, v0 );
342 v3_sub( pc, pb, v1 );
343 v3_cross( v1, v0, hit->normal );
344 v3_normalize( hit->normal );
345 v3_muladds( co, dir, hit->dist, hit->pos );
346 }
347
348 return count;
349 }
350
351 VG_STATIC bh_tree *scene_bh_create( void *lin_alloc, scene *s )
352 {
353 u32 triangle_count = s->indice_count / 3;
354 return bh_create( lin_alloc, &bh_system_scene, s, triangle_count, 2 );
355 }
356
357 #endif