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/*************************************************************************
* Copyright (C) 2010 Tavian Barnes <tavianator@gmail.com> *
* *
* This file is part of The Dimension Library. *
* *
* The Dimension Library is free software; you can redistribute it and/ *
* or modify it under the terms of the GNU Lesser General Public License *
* as published by the Free Software Foundation; either version 3 of the *
* License, or (at your option) any later version. *
* *
* The Dimension Library is distributed in the hope that it will be *
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty *
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
* Lesser General Public License for more details. *
* *
* You should have received a copy of the GNU Lesser General Public *
* License along with this program. If not, see *
* <http://www.gnu.org/licenses/>. *
*************************************************************************/
#include "dimension.h"
#include <errno.h>
static void
dmnsn_csg_free_fn(void *ptr)
{
dmnsn_object **params = ptr;
dmnsn_delete_object(params[1]);
dmnsn_delete_object(params[0]);
free(ptr);
}
/* Unions */
static dmnsn_intersection *
dmnsn_csg_union_intersection_fn(const dmnsn_object *csg, dmnsn_line line)
{
const dmnsn_object **params = csg->ptr;
dmnsn_line line1 = dmnsn_matrix_line_mul(params[0]->trans_inv, line);
dmnsn_line line2 = dmnsn_matrix_line_mul(params[1]->trans_inv, line);
dmnsn_intersection *i1 = (*params[0]->intersection_fn)(params[0], line1);
dmnsn_intersection *i2 = (*params[1]->intersection_fn)(params[1], line2);
if (i1) {
/* Transform the intersection back to the observer's view */
i1->ray = line;
i1->normal = dmnsn_vector_normalize(
dmnsn_vector_sub(
dmnsn_matrix_vector_mul(params[0]->trans, i1->normal),
dmnsn_matrix_vector_mul(params[0]->trans, dmnsn_zero)
)
);
if (!i1->texture)
i1->texture = csg->texture;
if (!i1->interior)
i1->interior = csg->interior;
}
if (i2) {
i2->ray = line;
i2->normal = dmnsn_vector_normalize(
dmnsn_vector_sub(
dmnsn_matrix_vector_mul(params[1]->trans, i2->normal),
dmnsn_matrix_vector_mul(params[1]->trans, dmnsn_zero)
)
);
if (!i2->texture)
i2->texture = csg->texture;
if (!i2->interior)
i2->interior = csg->interior;
}
if (!i1)
return i2;
if (!i2)
return i1;
if (i1->t < i2->t) {
dmnsn_delete_intersection(i2);
return i1;
} else {
dmnsn_delete_intersection(i1);
return i2;
}
}
static bool
dmnsn_csg_union_inside_fn(const dmnsn_object *csg, dmnsn_vector point)
{
dmnsn_object **params = csg->ptr;
return (*params[0]->inside_fn)(params[0], point)
|| (*params[1]->inside_fn)(params[1], point);
}
dmnsn_object *
dmnsn_new_csg_union(dmnsn_object *A, dmnsn_object *B)
{
if (A && B) {
A->trans_inv = dmnsn_matrix_inverse(A->trans);
B->trans_inv = dmnsn_matrix_inverse(B->trans);
dmnsn_object *csg = dmnsn_new_object();
if (csg) {
dmnsn_object **params = malloc(2*sizeof(dmnsn_object *));
if (!params) {
dmnsn_delete_object(csg);
dmnsn_delete_object(B);
dmnsn_delete_object(A);
errno = ENOMEM;
return NULL;
}
params[0] = A;
params[1] = B;
csg->ptr = params;
csg->intersection_fn = &dmnsn_csg_union_intersection_fn;
csg->inside_fn = &dmnsn_csg_union_inside_fn;
csg->free_fn = &dmnsn_csg_free_fn;
dmnsn_bounding_box Abox
= dmnsn_matrix_bounding_box_mul(A->trans, A->bounding_box);
dmnsn_bounding_box Bbox
= dmnsn_matrix_bounding_box_mul(B->trans, B->bounding_box);
csg->bounding_box.min = dmnsn_vector_min(Abox.min, Bbox.min);
csg->bounding_box.max = dmnsn_vector_max(Abox.max, Bbox.max);
return csg;
} else {
dmnsn_delete_object(B);
dmnsn_delete_object(A);
}
} else if (A) {
dmnsn_delete_object(B);
} else if (B) {
dmnsn_delete_object(A);
}
return NULL;
}
/* Intersections */
static dmnsn_intersection *
dmnsn_csg_intersection_intersection_fn(const dmnsn_object *csg, dmnsn_line line)
{
const dmnsn_object **params = csg->ptr;
dmnsn_line line1 = dmnsn_matrix_line_mul(params[0]->trans_inv, line);
dmnsn_line line2 = dmnsn_matrix_line_mul(params[1]->trans_inv, line);
dmnsn_intersection *i1 = (*params[0]->intersection_fn)(params[0], line1);
dmnsn_intersection *i2 = (*params[1]->intersection_fn)(params[1], line2);
if (i1) {
i1->ray = line;
i1->normal = dmnsn_vector_normalize(
dmnsn_vector_sub(
dmnsn_matrix_vector_mul(params[0]->trans, i1->normal),
dmnsn_matrix_vector_mul(params[0]->trans, dmnsn_zero)
)
);
if (!i1->texture)
i1->texture = csg->texture;
if (!i1->interior)
i1->interior = csg->interior;
dmnsn_vector point = dmnsn_line_point(i1->ray, i1->t);
point = dmnsn_matrix_vector_mul(params[1]->trans_inv, point);
if (!(*params[1]->inside_fn)(params[1], point)) {
dmnsn_delete_intersection(i1);
i1 = NULL;
}
}
if (i2) {
i2->ray = line;
i2->normal = dmnsn_vector_normalize(
dmnsn_vector_sub(
dmnsn_matrix_vector_mul(params[1]->trans, i2->normal),
dmnsn_matrix_vector_mul(params[1]->trans, dmnsn_zero)
)
);
if (!i2->texture)
i2->texture = csg->texture;
if (!i2->interior)
i2->interior = csg->interior;
dmnsn_vector point = dmnsn_line_point(i2->ray, i2->t);
point = dmnsn_matrix_vector_mul(params[0]->trans_inv, point);
if (!(*params[0]->inside_fn)(params[0], point)) {
dmnsn_delete_intersection(i2);
i2 = NULL;
}
}
if (!i1)
return i2;
if (!i2)
return i1;
if (i1->t > i2->t) {
dmnsn_delete_intersection(i2);
return i1;
} else {
dmnsn_delete_intersection(i1);
return i2;
}
}
static bool
dmnsn_csg_intersection_inside_fn(const dmnsn_object *csg, dmnsn_vector point)
{
dmnsn_object **params = csg->ptr;
return (*params[0]->inside_fn)(params[0], point)
&& (*params[1]->inside_fn)(params[1], point);
}
dmnsn_object *
dmnsn_new_csg_intersection(dmnsn_object *A, dmnsn_object *B)
{
if (A && B) {
A->trans_inv = dmnsn_matrix_inverse(A->trans);
B->trans_inv = dmnsn_matrix_inverse(B->trans);
dmnsn_object *csg = dmnsn_new_object();
if (csg) {
dmnsn_object **params = malloc(2*sizeof(dmnsn_object *));
if (!params) {
dmnsn_delete_object(csg);
dmnsn_delete_object(B);
dmnsn_delete_object(A);
errno = ENOMEM;
return NULL;
}
params[0] = A;
params[1] = B;
csg->ptr = params;
csg->intersection_fn = &dmnsn_csg_intersection_intersection_fn;
csg->inside_fn = &dmnsn_csg_intersection_inside_fn;
csg->free_fn = &dmnsn_csg_free_fn;
dmnsn_bounding_box Abox
= dmnsn_matrix_bounding_box_mul(A->trans, A->bounding_box);
dmnsn_bounding_box Bbox
= dmnsn_matrix_bounding_box_mul(B->trans, B->bounding_box);
csg->bounding_box.min = dmnsn_vector_min(Abox.min, Bbox.min);
csg->bounding_box.max = dmnsn_vector_max(Abox.max, Bbox.max);
return csg;
} else {
dmnsn_delete_object(B);
dmnsn_delete_object(A);
}
} else if (A) {
dmnsn_delete_object(B);
} else if (B) {
dmnsn_delete_object(A);
}
return NULL;
}
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