From 7b09710392d35fb55b52031d447a542d99fc6b4b Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Tue, 19 Aug 2014 17:10:03 -0400 Subject: Modularize the libdimension codebase. --- libdimension/triangle.c | 162 ------------------------------------------------ 1 file changed, 162 deletions(-) delete mode 100644 libdimension/triangle.c (limited to 'libdimension/triangle.c') diff --git a/libdimension/triangle.c b/libdimension/triangle.c deleted file mode 100644 index fdd2b96..0000000 --- a/libdimension/triangle.c +++ /dev/null @@ -1,162 +0,0 @@ -/************************************************************************* - * Copyright (C) 2009-2014 Tavian Barnes * - * * - * 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 * - * . * - *************************************************************************/ - -/** - * @file - * Triangles. See - * http://tavianator.com/2014/05/a-beautiful-raytriangle-intersection-method/ - * for a description of the intersection algorithm. - */ - -#include "dimension-internal.h" - -/// Optimized ray/triangle intersection test. -static inline bool -dmnsn_ray_triangle_intersection(dmnsn_line l, double *t, double *u, double *v) -{ - // See the change of basis in dmnsn_triangle_basis() - *t = -l.x0.z/l.n.z; - *u = l.x0.x + (*t)*l.n.x; - *v = l.x0.y + (*t)*l.n.y; - return *t >= 0.0 && *u >= 0.0 && *v >= 0.0 && *u + *v <= 1.0; -} - -/// Triangle intersection callback. -DMNSN_HOT static bool -dmnsn_triangle_intersection_fn(const dmnsn_object *object, dmnsn_line l, - dmnsn_intersection *intersection) -{ - double t, u, v; - if (dmnsn_ray_triangle_intersection(l, &t, &u, &v)) { - intersection->t = t; - intersection->normal = dmnsn_z; - return true; - } - - return false; -} - -/// Triangle inside callback. -static bool -dmnsn_triangle_inside_fn(const dmnsn_object *object, dmnsn_vector point) -{ - return false; -} - -/// Triangle bounding callback. -static dmnsn_bounding_box -dmnsn_triangle_bounding_fn(const dmnsn_object *object, dmnsn_matrix trans) -{ - dmnsn_vector a = dmnsn_transform_point(trans, dmnsn_zero); - dmnsn_vector b = dmnsn_transform_point(trans, dmnsn_x); - dmnsn_vector c = dmnsn_transform_point(trans, dmnsn_y); - - dmnsn_bounding_box box = dmnsn_new_bounding_box(a, a); - box = dmnsn_bounding_box_swallow(box, b); - box = dmnsn_bounding_box_swallow(box, c); - return box; -} - -/// Triangle vtable. -static const dmnsn_object_vtable dmnsn_triangle_vtable = { - .intersection_fn = dmnsn_triangle_intersection_fn, - .inside_fn = dmnsn_triangle_inside_fn, - .bounding_fn = dmnsn_triangle_bounding_fn, -}; - -/// Smooth triangle type. -typedef struct { - dmnsn_object object; - dmnsn_vector na, nab, nac; -} dmnsn_smooth_triangle; - -/// Smooth triangle intersection callback. -DMNSN_HOT static bool -dmnsn_smooth_triangle_intersection_fn(const dmnsn_object *object, dmnsn_line l, - dmnsn_intersection *intersection) -{ - const dmnsn_smooth_triangle *triangle = (const dmnsn_smooth_triangle *)object; - - double t, u, v; - if (dmnsn_ray_triangle_intersection(l, &t, &u, &v)) { - intersection->t = t; - intersection->normal = dmnsn_vector_add( - triangle->na, - dmnsn_vector_add( - dmnsn_vector_mul(u, triangle->nab), - dmnsn_vector_mul(v, triangle->nac) - ) - ); - return true; - } - - return false; -} - -/// Smooth triangle vtable. -static const dmnsn_object_vtable dmnsn_smooth_triangle_vtable = { - .intersection_fn = dmnsn_smooth_triangle_intersection_fn, - .inside_fn = dmnsn_triangle_inside_fn, - .bounding_fn = dmnsn_triangle_bounding_fn, -}; - -/// Make a change-of-basis matrix. -static inline dmnsn_matrix -dmnsn_triangle_basis(dmnsn_vector vertices[3]) -{ - // The new vector space has corners at <1, 0, 0>, <0, 1, 0>, and 0, - // corresponding to the basis (ab, ac, ab X ac). - dmnsn_vector ab = dmnsn_vector_sub(vertices[1], vertices[0]); - dmnsn_vector ac = dmnsn_vector_sub(vertices[2], vertices[0]); - dmnsn_vector normal = dmnsn_vector_cross(ab, ac); - return dmnsn_new_matrix4(ab, ac, normal, vertices[0]); -} - -dmnsn_object * -dmnsn_new_triangle(dmnsn_pool *pool, dmnsn_vector vertices[3]) -{ - dmnsn_object *object = dmnsn_new_object(pool); - object->vtable = &dmnsn_triangle_vtable; - object->intrinsic_trans = dmnsn_triangle_basis(vertices); - return object; -} - -dmnsn_object * -dmnsn_new_smooth_triangle(dmnsn_pool *pool, dmnsn_vector vertices[3], dmnsn_vector normals[3]) -{ - dmnsn_matrix P = dmnsn_triangle_basis(vertices); - - // Transform the given normals. - dmnsn_vector na = dmnsn_vector_normalized(dmnsn_transform_normal(P, normals[0])); - dmnsn_vector nb = dmnsn_vector_normalized(dmnsn_transform_normal(P, normals[1])); - dmnsn_vector nc = dmnsn_vector_normalized(dmnsn_transform_normal(P, normals[2])); - - dmnsn_smooth_triangle *triangle = DMNSN_PALLOC(pool, dmnsn_smooth_triangle); - triangle->na = na; - triangle->nab = dmnsn_vector_sub(nb, na); - triangle->nac = dmnsn_vector_sub(nc, na); - - dmnsn_object *object = &triangle->object; - dmnsn_init_object(object); - object->vtable = &dmnsn_smooth_triangle_vtable; - object->intrinsic_trans = P; - - return object; -} -- cgit v1.2.3