trisurf-ng.git - Gitblit

Samo Penic

2016-03-01 86b69b3803b1b31c040cede6b47bf617561b3b81

commit \| author \| age
d7639a	1	#include<stdlib.h>
SP	2	#include<stdio.h>
	3	#include "general.h"
	4	#include "triangle.h"
	5	#include<math.h>
	6
bb77ca	7	/** @brief Prepares the list for triangles.
632960	8	* @returns pointer to empty data structure for maintaining triangle list.
bb77ca	9	*
SP	10	* Create empty list for holding the information on triangles. Triangles are
	11	* added later on with triangle_add().
	12	* Returns pointer to the tlist datastructure it has created. This pointer must
	13	* be assigned to some variable or it will be lost.
	14	*
	15	*
	16	* Example of usage:
	17	* ts_triangle_list *tlist;
	18	* tlist=triangle_data_free();
	19	*
	20	* Initalized data structure for holding the information on triangles.
	21	*
	22	*/
a2a676	23	ts_triangle_list *init_triangle_list(){
SP	24	ts_triangle_list tlist=(ts_triangle_list )malloc(sizeof(ts_triangle_list));
d7639a	25	tlist->n = 0;
a2a676	26	tlist->tria=NULL;
SP	27	return tlist;
d7639a	28	}
SP	29
bb77ca	30	/** @brief Add the triangle to the triangle list and create necessary data
632960	31	* structures.
SP	32	* @param *tlist is a pointer to triangle list where triangle should be created
	33	* @param vtx1, vtx2, *vtx3 are the three vertices defining the triangle
	34	* @returns pointer to the newly created triangle on success and NULL if
	35	* triangle could not be created. It breaks program execution if memory
	36	* allocation of triangle list can't be done.
bb77ca	37	*
632960	38	* Add the triangle ts_triangle to the ts_triangle_list.
bb77ca	39	* The triangle list is resized, the ts_triangle is allocated and
632960	40	* triangle data is zeroed. Returned pointer to newly
SP	41	* created triangle doesn't need assigning, since it is
bb77ca	42	* referenced by triangle list.
SP	43	*
	44	* WARNING: Function can be accelerated a bit by removing the NULL checks.
	45	* However the time gained by removal doesn't justify the time spent by
	46	* debugging stupid NULL pointers.
	47	*
	48	* Example of usage:
	49	* triangle_add(tlist, vlist->vtx[1], vlist->vtx[2], vlist->vtx[3]);
	50	*
	51	* Creates a triangle with given vertices and puts it into the list.
	52	*
	53	*/
a2a676	54	ts_triangle triangle_add(ts_triangle_list tlist, ts_vertex vtx1, ts_vertex vtx2, ts_vertex *vtx3){
SP	55	if(vtx1==NULL \|\| vtx2==NULL \|\| vtx3==NULL){
	56	return NULL;
	57	}
d7639a	58	tlist->n++;
a2a676	59	tlist->tria=(ts_triangle *)realloc(tlist->tria,tlist->nsizeof(ts_triangle *));
SP	60	if(tlist->tria==NULL) fatal("Cannot reallocate memory for additional ts_triangle.",5);
	61
	62	tlist->tria[tlist->n-1]=(ts_triangle *)calloc(1,sizeof(ts_triangle));
	63	if(tlist->tria[tlist->n-1]==NULL) fatal("Cannot reallocate memory for additional ts_triangle.",5);
	64
d7639a	65	//NOW insert vertices!
a2a676	66	tlist->tria[tlist->n - 1]->idx=tlist->n-1;
41a035	67	tlist->tria[tlist->n - 1]->vertex[0]=vtx1;
SP	68	tlist->tria[tlist->n - 1]->vertex[1]=vtx2;
	69	tlist->tria[tlist->n - 1]->vertex[2]=vtx3;
a2a676	70	return tlist->tria[tlist->n-1];
d7639a	71	}
SP	72
bb77ca	73	/** @brief Add the neigbour to triangles.
632960	74	* @param *tria is a first triangle.
SP	75	* @param *ntria is a second triangle.
	76	* @returns TS_SUCCES on sucessful adition to the list, TS_FAIL if triangles
	77	* are NULL and breaks execution FATALY if memory allocation error occurs.
bb77ca	78	*
SP	79	* Add the neigbour to the list of neighbouring triangles. The
632960	80	* neighbouring triangles are those, who share two vertices and corresponding
SP	81	* bond. Function resizes
bb77ca	82	* the list and adds the pointer to neighbour. It receives two arguments of
dac2e5	83	* ts_triangle type. It then adds second triangle to the list of first
SP	84	* triangle, but not the opposite. Upon
bb77ca	85	* success it returns TS_SUCCESS, upon detecting NULL pointers
SP	86	* returns TS_FAIL and it FATALY ends when the data structure
	87	* cannot be resized.
	88	*
	89	*
	90	* WARNING: Function can be accelerated a bit by removing the NULL checks.
	91	* However the time gained by removal doesn't justify the time spent by
	92	* debugging stupid NULL pointers.
	93	*
	94	* Example of usage:
632960	95	* triangle_add_neighbour(tlist->tria[3], tlist->tria[4]);
bb77ca	96	*
632960	97	* Triangle 4 is a neighbour of triangle 3, but (strangely) not the
SP	98	* oposite. The function should be called again with the changed order of
	99	* triangles to make neighbourship mutual.
bb77ca	100	*
SP	101	*/
d7639a	102
SP	103	ts_bool triangle_add_neighbour(ts_triangle tria, ts_triangle ntria){
a2a676	104	if(tria==NULL \|\| ntria==NULL) return TS_FAIL;
41a035	105	tria->neigh_no++;
SP	106	tria->neigh=realloc(tria->neigh,tria->neigh_nosizeof(ts_triangle ));
	107	if(tria->neigh == NULL)
d7639a	108	fatal("Reallocation of memory failed during insertion of triangle neighbour in triangle_add_neighbour",3);
632960	109	tria->neigh[tria->neigh_no-1]=ntria;
d7639a	110	return TS_SUCCESS;
SP	111	}
	112
bb77ca	113	/** @brief Remove the neigbours from triangle.
632960	114	* @param *tria is a first triangle.
SP	115	* @param *ntria is neighbouring triangle.
	116	* @returns TS_SUCCESS on successful removal, TS_FAIL if triangles are not
	117	* neighbours and it breaks program execution FATALY if memory allocation
	118	* problem occurs.
bb77ca	119	*
SP	120	* Removes the neigbour from the list of neighbouring triangles. The
632960	121	* neighbouring triangles are those, who share two vertices and corresponding
SP	122	* bond. Function resizes
bb77ca	123	* the list and deletes the pointer to neighbour. It receives two arguments of
632960	124	* ts_triangle type. It then mutually removes triangles from eachouther
SP	125	* neighbour list. Upon
bb77ca	126	* success it returns TS_SUCCESS, upon failure to find the triangle in the
632960	127	* neighbour list returns TS_FAIL. It FATALY breaks program execution when the datastructure
SP	128	* cannot be resized due to memory constrain problems.
bb77ca	129	*
SP	130	* WARNING: The function doesn't check whether the pointer is NULL or invalid. It is the
	131	* job of programmer to make sure the pointer is valid.
	132	*
	133	* WARNING: Function is slow. Do not use it often!
	134	*
	135	* Example of usage:
	136	* triangle_remove_neighbour(tlist->tria[3], tlist->tria[4]);
	137	*
	138	* Triangles 3 and 4 are not neighbours anymore.
	139	*
	140	*/
d7639a	141	ts_bool triangle_remove_neighbour(ts_triangle tria, ts_triangle ntria){
a2a676	142	ts_uint i,j=0;
SP	143	if(tria==NULL \|\| ntria==NULL) return TS_FAIL;
	144
41a035	145	for(i=0;i<tria->neigh_no;i++){
SP	146	if(tria->neigh[i]!=ntria){
	147	tria->neigh[j]=tria->neigh[i];
d7639a	148	j++;
SP	149	}
	150	}
a2a676	151	if(j==i) {
SP	152	return TS_FAIL;
	153	}
41a035	154	tria->neigh_no--;
SP	155	tria->neigh=(ts_triangle *)realloc(tria->neigh,tria->neigh_nosizeof(ts_triangle *));
	156	if(tria->neigh == NULL){
2870ab	157	fprintf(stderr,"Ooops: tria->neigh_no=%d\n",tria->neigh_no);
a2a676	158	fatal("Reallocation of memory failed during removal of vertex neighbour in triangle_remove_neighbour",100);
SP	159	}
	160	/* we repeat the procedure for neighbour */
e19e79	161	j=0;
41a035	162	for(i=0;i<ntria->neigh_no;i++){
SP	163	if(ntria->neigh[i]!=tria){
	164	ntria->neigh[j]=ntria->neigh[i];
a2a676	165	j++;
SP	166	}
	167	}
	168	if(j==i) {
	169	return TS_FAIL;
	170	}
41a035	171	ntria->neigh_no--;
SP	172	ntria->neigh=(ts_triangle *)realloc(ntria->neigh,ntria->neigh_nosizeof(ts_triangle *));
	173	if(ntria->neigh == NULL){
2870ab	174	fprintf(stderr,"Ooops: ntria->neigh_no=%d\n",ntria->neigh_no);
a2a676	175	fatal("Reallocation of memory failed during removal of vertex neighbour in triangle_remove_neighbour",100);
SP	176	}
d7639a	177	return TS_SUCCESS;
SP	178	}
	179
bb77ca	180
632960	181	/** @brief Calculates normal vector of the triangle, its corresponding area and volume.
SP	182	* @param *tria is a triangle pointer for which normal, area and volume is
	183	* to be calculated.
	184	* @returns TS_SUCCESS on success. (always)
bb77ca	185	*
SP	186	* Calculate normal vector of the triangle (xnorm, ynorm and znorm) and stores
632960	187	* information. At the same time
SP	188	* triangle area is determined, since we already have the normal and volume of
	189	* triangular pyramid with given triangle as a base and vesicle centroid as a
	190	* tip.
bb77ca	191	*
SP	192	* Function receives one argument of type ts_triangle. It should be corectly
632960	193	* initialized. The
SP	194	* result is stored in triangle->xnorm, triangle->ynorm, triangle->znorm.
	195	* Area and volume are stored into triangle->area and triangle->volume.
	196	* Returns TS_SUCCESS on completion.
bb77ca	197	*
632960	198	* NOTE: Function uses math.h library. Function pow implementation is selected
SP	199	* accordind to the used TS_DOUBLE_* definition set in general.h, so it should
	200	* be compatible with any type of floating point precision.
bb77ca	201	*
SP	202	* Example of usage:
	203	* triangle_normal_vector(tlist->tria[3]);
	204	*
	205	* Computes normals and stores information into tlist->tria[3]->xnorm,
632960	206	* tlist->tria[3]->ynorm, tlist->tria[3]->znorm tlist->tria[3]->area and
SP	207	* tlist->tria[3]->volume.
bb77ca	208	*
SP	209	*/
d7639a	210	ts_bool triangle_normal_vector(ts_triangle *tria){
SP	211	ts_double x21,x31,y21,y31,z21,z31,xden;
8f6a69	212	x21=tria->vertex[1]->x - tria->vertex[0]->x;
SP	213	x31=tria->vertex[2]->x - tria->vertex[0]->x;
	214	y21=tria->vertex[1]->y - tria->vertex[0]->y;
	215	y31=tria->vertex[2]->y - tria->vertex[0]->y;
	216	z21=tria->vertex[1]->z - tria->vertex[0]->z;
	217	z31=tria->vertex[2]->z - tria->vertex[0]->z;
d7639a	218
41a035	219	tria->xnorm=y21z31 - z21y31;
SP	220	tria->ynorm=z21x31 - x21z31;
	221	tria->znorm=x21y31 - y21x31;
	222	xden=tria->xnorm*tria->xnorm +
	223	tria->ynorm*tria->ynorm +
	224	tria->znorm*tria->znorm;
d7639a	225	#ifdef TS_DOUBLE_DOUBLE
SP	226	xden=sqrt(xden);
	227	#endif
	228	#ifdef TS_DOUBLE_FLOAT
	229	xden=sqrtf(xden);
	230	#endif
	231	#ifdef TS_DOUBLE_LONGDOUBLE
	232	xden=sqrtl(xden);
	233	#endif
41a035	234	tria->xnorm=tria->xnorm/xden;
SP	235	tria->ynorm=tria->ynorm/xden;
	236	tria->znorm=tria->znorm/xden;
c9d07c	237
SP	238	/* Here it is an excellent point to recalculate volume of the triangle and
	239	* store it into datastructure. Volume is required at least by constant volume
	240	* calculation of vertex move and bondflip and spherical harmonics. */
	241	tria->volume=(tria->vertex[0]->x+ tria->vertex[1]->x + tria->vertex[2]->x) * tria->xnorm +
	242	(tria->vertex[0]->y+ tria->vertex[1]->y + tria->vertex[2]->y) * tria->ynorm +
	243	(tria->vertex[0]->z+ tria->vertex[1]->z + tria->vertex[2]->z) * tria->znorm;
	244	tria->volume=-xden*tria->volume/18.0;
	245	/* Also, area can be calculated in each triangle */
	246	tria->area=xden/2;
	247
	248
d7639a	249	return TS_SUCCESS;
SP	250	}
	251
bb77ca	252	/** @brief Frees the memory allocated for data structure of triangle list
632960	253	* @param *tlist is a pointer to datastructure triangle list to be freed.
SP	254	* @returns TS_SUCCESS on success (always).
bb77ca	255	*
SP	256	* Function frees the memory of ts_triangle_list previously allocated. It
	257	* accepts one argument, the address of data structure. It destroys all
	258	* ts_triangle's in the list with underlying data (by calling
	259	* triangle_data_free()), and the list itself.
	260	*
	261	* Should be used eveytime the deletion of triangle list (created by
	262	* init_triangle_list() and altered by add_triangle() or remove_triangle()) is desired.
	263	*
	264	* WARNING: The function doesn't check whether the pointer is NULL or invalid. It is the
	265	* job of programmer to make sure the pointer is valid.
	266	*
	267	* WARNING: Careful when destroying triangle lists. There could be pointers to
	268	* that information remaining in structures like vertex_data. This pointers
	269	* will be rendered invalid by this operation and should not be used anymore.
	270	*
	271	* Example of usage:
	272	* triangle_list_free(tlist);
	273	*
	274	* Clears all the information on triangles.
	275	*
	276	*/
d7639a	277	ts_bool triangle_list_free(ts_triangle_list *tlist){
a2a676	278	ts_uint i;
d7639a	279	for(i=0;i<tlist->n;i++){
41a035	280	if(tlist->tria[i]->neigh!=NULL) free(tlist->tria[i]->neigh);
a2a676	281	free(tlist->tria[i]);
d7639a	282	}
a2a676	283	free(tlist->tria);
SP	284	free(tlist);
d7639a	285	return TS_SUCCESS;
SP	286	}
	287