diff options
Diffstat (limited to 'libdimension')
| -rw-r--r-- | libdimension/Makefile.am | 3 | ||||
| -rw-r--r-- | libdimension/dimension/objects.h | 10 | ||||
| -rw-r--r-- | libdimension/tests/render.c | 33 | ||||
| -rw-r--r-- | libdimension/triangle.c | 83 |
4 files changed, 128 insertions, 1 deletions
diff --git a/libdimension/Makefile.am b/libdimension/Makefile.am index 0f3dee5..b042fc9 100644 --- a/libdimension/Makefile.am +++ b/libdimension/Makefile.am @@ -111,7 +111,8 @@ libdimension_la_SOURCES = $(nobase_include_HEADERS) \ threads.c \ threads.h \ timer.c \ - torus.c + torus.c \ + triangle.c libdimension_la_CFLAGS = $(AM_CFLAGS) libdimension_la_LDFLAGS = -version-info 0:0:0 -no-undefined $(AM_LDFLAGS) libdimension_la_LIBADD = -lm -lpthread diff --git a/libdimension/dimension/objects.h b/libdimension/dimension/objects.h index aa53329..ba9547d 100644 --- a/libdimension/dimension/objects.h +++ b/libdimension/dimension/objects.h @@ -26,6 +26,16 @@ #include <stdbool.h> /** + * A triangle. + * @param[in] a The first corner of the triangle. + * @param[in] b The second corner of the triangle. + * @param[in] c The third corner of the triangle. + */ +dmnsn_object *dmnsn_new_triangle(dmnsn_vector a, + dmnsn_vector b, + dmnsn_vector c); + +/** * A plane. * @param[in] normal The normal vector of the plane. * @return A plane through the origin, with the given normal. diff --git a/libdimension/tests/render.c b/libdimension/tests/render.c index 04897d6..a9d20d7 100644 --- a/libdimension/tests/render.c +++ b/libdimension/tests/render.c @@ -190,6 +190,39 @@ dmnsn_new_test_scene(void) ); dmnsn_array_push(scene->objects, &spike); + /* Triangle strip */ + + dmnsn_array *strip_array = dmnsn_new_array(sizeof(dmnsn_object *)); + dmnsn_vector a = dmnsn_zero; + dmnsn_vector b = dmnsn_new_vector(0.0, sqrt(3.0)/2.0, 0.5); + dmnsn_vector c = dmnsn_z; + dmnsn_texture *strip_textures[3] = { + dmnsn_new_texture(), + dmnsn_new_texture(), + dmnsn_new_texture(), + }; + strip_textures[0]->pigment = dmnsn_new_solid_pigment(dmnsn_red); + strip_textures[1]->pigment = dmnsn_new_solid_pigment(dmnsn_orange); + strip_textures[2]->pigment = dmnsn_new_solid_pigment(dmnsn_yellow); + for (unsigned int i = 0; i < 128; ++i) { + dmnsn_object *triangle = dmnsn_new_triangle(a, b, c); + triangle->texture = strip_textures[i%3]; + DMNSN_INCREF(triangle->texture); + dmnsn_array_push(strip_array, &triangle); + + a = b; + b = c; + c = dmnsn_vector_add(a, dmnsn_z); + } + for (unsigned int i = 0; i < 3; ++i) { + dmnsn_delete_texture(strip_textures[i]); + } + + dmnsn_object *strip = dmnsn_new_csg_union(strip_array); + dmnsn_delete_array(strip_array); + strip->trans = dmnsn_translation_matrix(dmnsn_new_vector(5.0, -2.0, -4.0)); + dmnsn_array_push(scene->objects, &strip); + dmnsn_object *plane = dmnsn_new_plane(dmnsn_new_vector(0.0, 1.0, 0.0)); plane->trans = dmnsn_translation_matrix(dmnsn_new_vector(0.0, -2.0, 0.0)); dmnsn_pattern *checker1 = dmnsn_new_checker_pattern(); diff --git a/libdimension/triangle.c b/libdimension/triangle.c new file mode 100644 index 0000000..bd54e1a --- /dev/null +++ b/libdimension/triangle.c @@ -0,0 +1,83 @@ +/************************************************************************* + * Copyright (C) 2009-2010 Tavian Barnes <tavianator@tavianator.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/>. * + *************************************************************************/ + +/** + * @file + * Triangles. + */ + +#include "dimension.h" + +typedef struct dmnsn_triangle_payload { + dmnsn_vector a, ab, ac, normal; +} dmnsn_triangle_payload; + +/** Triangle intersection callback. */ +static bool +dmnsn_triangle_intersection_fn(const dmnsn_object *triangle, dmnsn_line l, + dmnsn_intersection *intersection) +{ + const dmnsn_triangle_payload *payload = triangle->ptr; + + double den = -dmnsn_vector_dot(l.n, payload->normal); + dmnsn_vector ax0 = dmnsn_vector_sub(l.x0, payload->a); + double t = dmnsn_vector_dot(ax0, payload->normal)/den; + double u = -dmnsn_vector_dot(l.n, dmnsn_vector_cross(ax0, payload->ac))/den; + double v = -dmnsn_vector_dot(l.n, dmnsn_vector_cross(payload->ab, ax0))/den; + if (t >= 0.0 && u >= 0.0 && v >= 0.0 && u + v <= 1.0) { + intersection->ray = l; + intersection->t = t; + intersection->normal = payload->normal; + intersection->texture = triangle->texture; + intersection->interior = triangle->interior; + return true; + } + + return false; +} + +/** Triangle inside callback. */ +static bool +dmnsn_triangle_inside_fn(const dmnsn_object *triangle, dmnsn_vector point) +{ + return false; +} + +/* Allocate a new triangle */ +dmnsn_object * +dmnsn_new_triangle(dmnsn_vector a, dmnsn_vector b, dmnsn_vector c) +{ + dmnsn_object *triangle = dmnsn_new_object(); + + dmnsn_triangle_payload *payload = + dmnsn_malloc(sizeof(dmnsn_triangle_payload)); + payload->a = a; + payload->ab = dmnsn_vector_sub(b, a); + payload->ac = dmnsn_vector_sub(c, a); + payload->normal = dmnsn_vector_cross(payload->ab, payload->ac); + + triangle->ptr = payload; + triangle->intersection_fn = dmnsn_triangle_intersection_fn; + triangle->inside_fn = dmnsn_triangle_inside_fn; + triangle->free_fn = dmnsn_free; + triangle->bounding_box.min = dmnsn_vector_min(dmnsn_vector_min(a, b), c); + triangle->bounding_box.max = dmnsn_vector_max(dmnsn_vector_max(a, b), c); + return triangle; +} |