right hand yellow
[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 typedef struct scene_vert scene_vert;
10
11 #pragma pack(push,1)
12
13 /* 32 byte vertexs, we don't care about the normals too much,
14 * maybe possible to bring down uv to i16s too */
15 struct scene_vert
16 {
17 v3f co; /* 3*32 */
18 v2f uv; /* 2*32 */
19 i8 norm[4]; /* 4*8 */
20 u16 unused[4];
21 };
22
23 #pragma pack(pop)
24
25 struct scene
26 {
27 scene_vert *arrvertices;
28
29 u32 *arrindices;
30
31 u32 vertex_count, indice_count,
32 max_vertices, max_indices;
33
34 boxf bbx;
35 mdl_submesh submesh;
36 };
37
38 /* Initialize a scene description with bounded buffers */
39 VG_STATIC scene *scene_init( void *lin_alloc, u32 max_verts, u32 max_indices )
40 {
41 u32 vertex_length = max_verts * sizeof(scene_vert),
42 index_length = max_indices * sizeof(u32),
43 tot_size = sizeof(scene) + vertex_length + index_length;
44
45 scene *pscene = vg_linear_alloc( lin_alloc, tot_size );
46
47 pscene->arrvertices = (scene_vert *)(pscene+1);
48 pscene->arrindices = (u32 *)( pscene->arrvertices + max_verts );
49
50 pscene->vertex_count = 0;
51 pscene->indice_count = 0;
52 pscene->max_vertices = max_verts;
53 pscene->max_indices = max_indices;
54
55 memset( &pscene->submesh, 0, sizeof(mdl_submesh) );
56
57 v3_fill( pscene->bbx[0], 999999.9f );
58 v3_fill( pscene->bbx[1], -999999.9f );
59
60 return pscene;
61 }
62
63 VG_STATIC void scene_vert_pack_norm( scene_vert *vert, v3f norm )
64 {
65 v3f n;
66 v3_muls( norm, 127.0f, n );
67 v3_minv( n, (v3f){ 127.0f, 127.0f, 127.0f }, n );
68 v3_maxv( n, (v3f){ -127.0f, -127.0f, -127.0f }, n );
69 vert->norm[0] = n[0];
70 vert->norm[1] = n[1];
71 vert->norm[2] = n[2];
72 vert->norm[3] = 0; /* free byte :D */
73 }
74
75 /*
76 * Append a model into the scene with a given transform
77 */
78 VG_STATIC void scene_add_mdl_submesh( scene *pscene, mdl_context *mdl,
79 mdl_submesh *sm, m4x3f transform )
80 {
81 if( pscene->vertex_count + sm->vertex_count > pscene->max_vertices ){
82 vg_error( "%u(current) + %u > %u\n", pscene->vertex_count,
83 sm->vertex_count,
84 pscene->max_vertices );
85
86 vg_warn( "%p ... %p\n", pscene, sm );
87 vg_fatal_exit_loop( "Scene vertex buffer overflow" );
88 }
89
90 if( pscene->indice_count + sm->indice_count > pscene->max_indices ){
91 vg_error( "%u(current) + %u > %u\n", pscene->indice_count,
92 sm->indice_count,
93 pscene->max_indices );
94 vg_warn( "%p ... %p\n", pscene, sm );
95
96 vg_fatal_exit_loop( "Scene index buffer overflow" );
97 }
98
99 mdl_vert *src_verts = mdl_arritm( &mdl->verts, sm->vertex_start );
100 scene_vert *dst_verts = &pscene->arrvertices[ pscene->vertex_count ];
101
102 u32 *src_indices = mdl_arritm( &mdl->indices, sm->indice_start ),
103 *dst_indices = &pscene->arrindices[ pscene->indice_count ];
104
105 /* Transform and place vertices */
106 boxf bbxnew;
107 box_copy( sm->bbx, bbxnew );
108 m4x3_transform_aabb( transform, bbxnew );
109 box_concat( pscene->bbx, bbxnew );
110
111 m3x3f normal_matrix;
112 m3x3_copy( transform, normal_matrix );
113 v3_normalize( normal_matrix[0] );
114 v3_normalize( normal_matrix[1] );
115 v3_normalize( normal_matrix[2] );
116
117 for( u32 i=0; i<sm->vertex_count; i++ ){
118 mdl_vert *src = &src_verts[ i ];
119 scene_vert *pvert = &dst_verts[ i ];
120
121 m4x3_mulv( transform, src->co, pvert->co );
122
123 v3f normal;
124 m3x3_mulv( normal_matrix, src->norm, normal );
125 scene_vert_pack_norm( pvert, normal );
126
127 v2_copy( src->uv, pvert->uv );
128 }
129
130 for( u32 i=0; i<sm->indice_count; i++ )
131 dst_indices[i] = src_indices[i] + pscene->vertex_count;
132
133 pscene->vertex_count += sm->vertex_count;
134 pscene->indice_count += sm->indice_count;
135 }
136
137 /*
138 * One by one adders for simplified access (mostly procedural stuff)
139 */
140 VG_STATIC void scene_push_tri( scene *pscene, u32 tri[3] )
141 {
142 if( pscene->indice_count + 3 > pscene->max_indices )
143 vg_fatal_exit_loop( "Scene vertex buffer overflow" );
144
145 u32 *dst = &pscene->arrindices[ pscene->indice_count ];
146
147 dst[0] = tri[0];
148 dst[1] = tri[1];
149 dst[2] = tri[2];
150
151 pscene->indice_count += 3;
152 }
153
154 VG_STATIC void scene_push_vert( scene *pscene, scene_vert *v )
155 {
156 if( pscene->vertex_count + 1 > pscene->max_vertices )
157 vg_fatal_exit_loop( "Scene vertex buffer overflow" );
158
159 scene_vert *dst = &pscene->arrvertices[ pscene->vertex_count ];
160 *dst = *v;
161
162 pscene->vertex_count ++;
163 }
164
165 VG_STATIC void scene_copy_slice( scene *pscene, mdl_submesh *sm )
166 {
167 sm->indice_start = pscene->submesh.indice_start;
168 sm->indice_count = pscene->indice_count - sm->indice_start;
169
170 sm->vertex_start = pscene->submesh.vertex_start;
171 sm->vertex_count = pscene->vertex_count - sm->vertex_start;
172
173 pscene->submesh.indice_start = pscene->indice_count;
174 pscene->submesh.vertex_start = pscene->vertex_count;
175 }
176
177 /* finalization: tightly pack data */
178 __attribute__((warn_unused_result))
179 VG_STATIC scene *scene_fix( void *lin_alloc, scene *pscene )
180 {
181 /* FIXME: Why is this disabled? */
182
183 u32 vertex_count = pscene->vertex_count,
184 indice_count = pscene->indice_count,
185 vertex_length = vertex_count * sizeof(scene_vert),
186 index_length = indice_count * sizeof(u32),
187 tot_size = vg_align8(sizeof(scene) + vertex_length + index_length);
188
189 /* copy down index data */
190 void *dst_indices = pscene->arrvertices + vertex_count;
191 memmove( dst_indices, pscene->arrindices, index_length );
192
193 /* realloc */
194 pscene = vg_linear_resize( lin_alloc, pscene, tot_size );
195
196 pscene->arrvertices = (scene_vert *)(pscene+1);
197 pscene->arrindices = (u32 *)(pscene->arrvertices+vertex_count);
198 pscene->max_vertices = vertex_count;
199 pscene->max_indices = indice_count;
200
201 return pscene;
202 }
203
204 #if 0
205 /* finalization: delete any offline buffers and reduce size */
206 __attribute__((warn_unused_result))
207 VG_STATIC scene *scene_free_offline_buffers( void *lin_alloc, scene *pscene )
208 {
209 u32 tot_size = sizeof(scene);
210
211 scene *src_scene = pscene;
212 mdl_vert *src_verts = pscene->arrvertices;
213 u32 *src_indices = pscene->arrindices;
214
215 scene *dst_scene = vg_linear_resize( lin_alloc, pscene, tot_size );
216 memcpy( dst_scene, src_scene, sizeof(scene) );
217
218 dst_scene->arrindices = NULL;
219 dst_scene->arrvertices = NULL;
220
221 return dst_scene;
222 }
223 #endif
224
225 VG_STATIC void scene_upload( scene *pscene, glmesh *mesh )
226 {
227 //assert( mesh->loaded == 0 );
228
229 glGenVertexArrays( 1, &mesh->vao );
230 glGenBuffers( 1, &mesh->vbo );
231 glGenBuffers( 1, &mesh->ebo );
232 glBindVertexArray( mesh->vao );
233
234 size_t stride = sizeof(scene_vert);
235
236 glBindBuffer( GL_ARRAY_BUFFER, mesh->vbo );
237 glBufferData( GL_ARRAY_BUFFER, pscene->vertex_count*stride,
238 pscene->arrvertices, GL_STATIC_DRAW );
239
240 glBindVertexArray( mesh->vao );
241 glBindBuffer( GL_ELEMENT_ARRAY_BUFFER, mesh->ebo );
242 glBufferData( GL_ELEMENT_ARRAY_BUFFER, pscene->indice_count*sizeof(u32),
243 pscene->arrindices, GL_STATIC_DRAW );
244
245 /* 0: coordinates */
246 glVertexAttribPointer( 0, 3, GL_FLOAT, GL_FALSE, stride, (void*)0 );
247 glEnableVertexAttribArray( 0 );
248
249 /* 1: normal */
250 glVertexAttribPointer( 1, 4, GL_BYTE, GL_TRUE,
251 stride, (void *)offsetof(scene_vert, norm) );
252 glEnableVertexAttribArray( 1 );
253
254 /* 2: uv */
255 glVertexAttribPointer( 2, 2, GL_FLOAT, GL_FALSE,
256 stride, (void *)offsetof(scene_vert, uv) );
257 glEnableVertexAttribArray( 2 );
258
259 #if 0
260 /* 3: light cluster */
261 glVertexAttribIPointer( 3, 4, GL_UNSIGNED_SHORT,
262 stride, (void *)offsetof(scene_vert, lights) );
263 glEnableVertexAttribArray( 3 );
264 #endif
265
266 VG_CHECK_GL_ERR();
267
268 mesh->indice_count = pscene->indice_count;
269 mesh->loaded = 1;
270
271 vg_info( "Scene upload ( XYZ_f32 UV_f32 XYZW_i8 )[ u32 ]\n" );
272 vg_info( " indices:%u\n", pscene->indice_count );
273 vg_info( " verts:%u\n", pscene->vertex_count );
274 }
275
276 /*
277 * BVH implementation
278 */
279
280 VG_STATIC void scene_bh_expand_bound( void *user, boxf bound, u32 item_index )
281 {
282 scene *s = user;
283 scene_vert *pa = &s->arrvertices[ s->arrindices[item_index*3+0] ],
284 *pb = &s->arrvertices[ s->arrindices[item_index*3+1] ],
285 *pc = &s->arrvertices[ s->arrindices[item_index*3+2] ];
286
287 box_addpt( bound, pa->co );
288 box_addpt( bound, pb->co );
289 box_addpt( bound, pc->co );
290 }
291
292 VG_STATIC float scene_bh_centroid( void *user, u32 item_index, int axis )
293 {
294 scene *s = user;
295 scene_vert *pa = &s->arrvertices[ s->arrindices[item_index*3+0] ],
296 *pb = &s->arrvertices[ s->arrindices[item_index*3+1] ],
297 *pc = &s->arrvertices[ s->arrindices[item_index*3+2] ];
298
299 #if 0
300
301 float min, max;
302
303 min = vg_minf( pa->co[axis], pb->co[axis] );
304 max = vg_maxf( pa->co[axis], pb->co[axis] );
305 min = vg_minf( min, pc->co[axis] );
306 max = vg_maxf( max, pc->co[axis] );
307
308 return (min+max) * 0.5f;
309
310 #else
311 return (pa->co[axis] + pb->co[axis] + pc->co[axis]) * (1.0f/3.0f);
312 #endif
313 }
314
315 VG_STATIC void scene_bh_swap( void *user, u32 ia, u32 ib )
316 {
317 scene *s = user;
318
319 u32 *ti = &s->arrindices[ia*3];
320 u32 *tj = &s->arrindices[ib*3];
321
322 u32 temp[3];
323 temp[0] = ti[0];
324 temp[1] = ti[1];
325 temp[2] = ti[2];
326
327 ti[0] = tj[0];
328 ti[1] = tj[1];
329 ti[2] = tj[2];
330
331 tj[0] = temp[0];
332 tj[1] = temp[1];
333 tj[2] = temp[2];
334 }
335
336 VG_STATIC void scene_bh_debug( void *user, u32 item_index )
337 {
338 scene *s = user;
339 u32 idx = item_index*3;
340 scene_vert *pa = &s->arrvertices[ s->arrindices[ idx+0 ] ],
341 *pb = &s->arrvertices[ s->arrindices[ idx+1 ] ],
342 *pc = &s->arrvertices[ s->arrindices[ idx+2 ] ];
343
344 vg_line( pa->co, pb->co, 0xff0000ff );
345 vg_line( pb->co, pc->co, 0xff0000ff );
346 vg_line( pc->co, pa->co, 0xff0000ff );
347 }
348
349 VG_STATIC int scene_bh_ray( void *user, u32 index, v3f co,
350 v3f dir, ray_hit *hit )
351 {
352 scene *s = user;
353 v3f positions[3];
354
355 u32 *tri = &s->arrindices[ index*3 ];
356
357 for( int i=0; i<3; i++ )
358 v3_copy( s->arrvertices[tri[i]].co, positions[i] );
359
360 float t;
361 if(ray_tri( positions, co, dir, &t ))
362 {
363 if( t < hit->dist )
364 {
365 hit->dist = t;
366 hit->tri = tri;
367 return 1;
368 }
369 }
370
371 return 0;
372 }
373
374 VG_STATIC void scene_bh_closest( void *user, u32 index, v3f point, v3f closest )
375 {
376 scene *s = user;
377
378 v3f positions[3];
379 u32 *tri = &s->arrindices[ index*3 ];
380 for( int i=0; i<3; i++ )
381 v3_copy( s->arrvertices[tri[i]].co, positions[i] );
382
383 closest_on_triangle_1( point, positions, closest );
384 }
385
386 VG_STATIC bh_system bh_system_scene =
387 {
388 .expand_bound = scene_bh_expand_bound,
389 .item_centroid = scene_bh_centroid,
390 .item_closest = scene_bh_closest,
391 .item_swap = scene_bh_swap,
392 .item_debug = scene_bh_debug,
393 .cast_ray = scene_bh_ray
394 };
395
396 /*
397 * An extra step is added onto the end to calculate the hit normal
398 */
399 VG_STATIC int scene_raycast( scene *s, bh_tree *bh,
400 v3f co, v3f dir, ray_hit *hit )
401 {
402 int count = bh_ray( bh, co, dir, hit );
403
404 if( count )
405 {
406 v3f v0, v1;
407
408 float *pa = s->arrvertices[hit->tri[0]].co,
409 *pb = s->arrvertices[hit->tri[1]].co,
410 *pc = s->arrvertices[hit->tri[2]].co;
411
412 v3_sub( pa, pb, v0 );
413 v3_sub( pc, pb, v1 );
414 v3_cross( v1, v0, hit->normal );
415 v3_normalize( hit->normal );
416 v3_muladds( co, dir, hit->dist, hit->pos );
417 }
418
419 return count;
420 }
421
422 VG_STATIC bh_tree *scene_bh_create( void *lin_alloc, scene *s )
423 {
424 u32 triangle_count = s->indice_count / 3;
425 return bh_create( lin_alloc, &bh_system_scene, s, triangle_count, 2 );
426 }
427
428 #endif