unify positive and negative zeros in stl_check_facets_exact() and stl_check_facets_nearby()
New function stl_transform() by a 3x4 matrix.
Some constness improvements.
This commit is contained in:
bubnikv 2017-02-26 21:59:09 +01:00
parent b7aeeb968b
commit efb02f71f0
4 changed files with 43 additions and 27 deletions

View file

@ -82,6 +82,16 @@ stl_check_facets_exact(stl_file *stl) {
for(i = 0; i < stl->stats.number_of_facets; i++) {
facet = stl->facet_start[i];
// Positive and negative zeros are possible in the floats, which are considered equal by the FP unit.
// When using a memcmp on raw floats, those numbers report to be different.
// Unify all +0 and -0 to +0 to make the floats equal under memcmp.
{
uint32_t *f = (uint32_t*)&facet;
for (int j = 0; j < 12; ++ j, ++ f) // 3x vertex + normal: 4x3 = 12 floats
if (*f == 0x80000000)
// Negative zero, switch to positive zero.
*f = 0;
}
/* If any two of the three vertices are found to be exactally the same, call them degenerate and remove the facet. */
if( !memcmp(&facet.vertex[0], &facet.vertex[1],
@ -278,6 +288,16 @@ stl_check_facets_nearby(stl_file *stl, float tolerance) {
for(i = 0; i < stl->stats.number_of_facets; i++) {
facet = stl->facet_start[i];
// Positive and negative zeros are possible in the floats, which are considered equal by the FP unit.
// When using a memcmp on raw floats, those numbers report to be different.
// Unify all +0 and -0 to +0 to make the floats equal under memcmp.
{
uint32_t *f = (uint32_t*)&facet;
for (int j = 0; j < 12; ++ j, ++ f) // 3x vertex + normal: 4x3 = 12 floats
if (*f == 0x80000000)
// Negative zero, switch to positive zero.
*f = 0;
}
for(j = 0; j < 3; j++) {
if(stl->neighbors_start[i].neighbor[j] == -1) {
edge[j].facet_number = i;

View file

@ -163,7 +163,7 @@ typedef struct {
} stl_file;
extern void stl_open(stl_file *stl, char *file);
extern void stl_open(stl_file *stl, const char *file);
extern void stl_close(stl_file *stl);
extern void stl_stats_out(stl_file *stl, FILE *file, char *input_file);
extern void stl_print_edges(stl_file *stl, FILE *file);
@ -196,6 +196,7 @@ extern void stl_rotate_z(stl_file *stl, float angle);
extern void stl_mirror_xy(stl_file *stl);
extern void stl_mirror_yz(stl_file *stl);
extern void stl_mirror_xz(stl_file *stl);
extern void stl_transform(stl_file *stl, float *trafo3x4);
extern void stl_open_merge(stl_file *stl, char *file);
extern void stl_invalidate_shared_vertices(stl_file *stl);
extern void stl_generate_shared_vertices(stl_file *stl);
@ -210,7 +211,7 @@ extern void stl_calculate_volume(stl_file *stl);
extern void stl_repair(stl_file *stl, int fixall_flag, int exact_flag, int tolerance_flag, float tolerance, int increment_flag, float increment, int nearby_flag, int iterations, int remove_unconnected_flag, int fill_holes_flag, int normal_directions_flag, int normal_values_flag, int reverse_all_flag, int verbose_flag);
extern void stl_initialize(stl_file *stl);
extern void stl_count_facets(stl_file *stl, char *file);
extern void stl_count_facets(stl_file *stl, const char *file);
extern void stl_allocate(stl_file *stl);
extern void stl_read(stl_file *stl, int first_facet, int first);
extern void stl_facet_stats(stl_file *stl, stl_facet facet, int first);

View file

@ -32,7 +32,7 @@
#endif
void
stl_open(stl_file *stl, char *file) {
stl_open(stl_file *stl, const char *file) {
stl_initialize(stl);
stl_count_facets(stl, file);
stl_allocate(stl);
@ -48,7 +48,7 @@ stl_initialize(stl_file *stl) {
}
void
stl_count_facets(stl_file *stl, char *file) {
stl_count_facets(stl_file *stl, const char *file) {
long file_size;
int header_num_facets;
int num_facets;
@ -308,29 +308,6 @@ stl_read(stl_file *stl, int first_facet, int first) {
printf("stl_read: facet %d.z = %e\r\n", j, facet.vertex[j].z);
}
#endif
#if 1
{
// Positive and negative zeros are possible in the floats, which are considered equal by the FP unit.
// When using a memcmp on raw floats, those numbers report to be different.
// Unify all +0 and -0 to +0 to make the floats equal under memcmp.
uint32_t *f = (uint32_t*)&facet;
for (int j = 0; j < 12; ++ j, ++ f) // 3x vertex + normal: 4x3 = 12 floats
if (*f == 0x80000000)
// Negative zero, switch to positive zero.
*f = 0;
}
#else
{
// Due to the nature of the floating point numbers, close to zero values may be represented with singificantly higher precision
// than the rest of the vertices. Round them to zero.
float *f = (float*)&facet;
for (int j = 0; j < 12; ++ j, ++ f) // 3x vertex + normal: 4x3 = 12 floats
if (*f > -1e-12f && *f < 1e-12f)
// Negative zero, switch to positive zero.
*f = 0;
}
#endif
/* Write the facet into memory. */
memcpy(stl->facet_start+i, &facet, SIZEOF_STL_FACET);
stl_facet_stats(stl, facet, first);

View file

@ -185,6 +185,24 @@ static void calculate_normals(stl_file *stl) {
}
}
void stl_transform(stl_file *stl, float *trafo3x4) {
int i_face, i_vertex, i, j;
if (stl->error)
return;
for (i_face = 0; i_face < stl->stats.number_of_facets; ++ i_face) {
stl_vertex *vertices = stl->facet_start[i_face].vertex;
for (i_vertex = 0; i_vertex < 3; ++ i_vertex) {
stl_vertex &v_dst = vertices[i_vertex];
stl_vertex v_src = v_dst;
v_dst.x = trafo3x4[0] * v_src.x + trafo3x4[1] * v_src.y + trafo3x4[2] * v_src.z + trafo3x4[3];
v_dst.y = trafo3x4[4] * v_src.x + trafo3x4[5] * v_src.y + trafo3x4[6] * v_src.z + trafo3x4[7];
v_dst.z = trafo3x4[8] * v_src.x + trafo3x4[9] * v_src.y + trafo3x4[10] * v_src.z + trafo3x4[11];
}
}
stl_get_size(stl);
calculate_normals(stl);
}
void
stl_rotate_x(stl_file *stl, float angle) {
int i;