From 9b6ca3e20b1d0a9ab7f821963c63c9b2b3c4fc40 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Wed, 13 May 2009 22:58:44 +0000 Subject: Begin object type, with sphere example. --- libdimension/Makefile.am | 4 +-- libdimension/array.c | 2 +- libdimension/dimension/object.h | 9 ++++++ libdimension/dimension/sphere.h | 31 ++++++++++++++++++ libdimension/object.c | 34 ++++++++++++++++++++ libdimension/sphere.c | 69 +++++++++++++++++++++++++++++++++++++++++ 6 files changed, 146 insertions(+), 3 deletions(-) create mode 100644 libdimension/dimension/sphere.h create mode 100644 libdimension/object.c create mode 100644 libdimension/sphere.c diff --git a/libdimension/Makefile.am b/libdimension/Makefile.am index 7114b04..136d652 100644 --- a/libdimension/Makefile.am +++ b/libdimension/Makefile.am @@ -17,10 +17,10 @@ ## along with this program. If not, see . ## ########################################################################### -nobase_include_HEADERS = dimension.h dimension/array.h dimension/canvas.h dimension/color.h dimension/error.h dimension/geometry.h dimension/png.h +nobase_include_HEADERS = dimension.h dimension/array.h dimension/canvas.h dimension/color.h dimension/error.h dimension/geometry.h dimension/png.h dimension/object.h dimension/sphere.h lib_LTLIBRARIES = libdimension.la -libdimension_la_SOURCES = $(nobase_include_HEADERS) array.c canvas.c color.c error.c geometry.c png.c +libdimension_la_SOURCES = $(nobase_include_HEADERS) array.c canvas.c color.c error.c geometry.c png.c object.c sphere.c libdimension_la_LDFLAGS = -version-info 0:0:0 libdimension_la_LIBADD = -lm -lpthread -lpng diff --git a/libdimension/array.c b/libdimension/array.c index 97ce716..e6e4363 100644 --- a/libdimension/array.c +++ b/libdimension/array.c @@ -24,7 +24,7 @@ dmnsn_array * dmnsn_new_array(size_t obj_size) { - dmnsn_array *array = malloc(sizeof(array)); + dmnsn_array *array = malloc(sizeof(dmnsn_array)); if (array) { array->obj_size = obj_size; array->length = 0; diff --git a/libdimension/dimension/object.h b/libdimension/dimension/object.h index 737a49d..c79d62e 100644 --- a/libdimension/dimension/object.h +++ b/libdimension/dimension/object.h @@ -26,9 +26,18 @@ */ typedef dmnsn_array *dmnsn_object_intersections_fn(dmnsn_line line); +typedef int dmnsn_object_inside_fn(dmnsn_vector point); typedef struct { + /* Generic pointer for object info */ + void *ptr; + + /* Callback functions */ dmnsn_object_intersections_fn *intersections_fn; + dmnsn_object_inside_fn *inside_fn; } dmnsn_object; +dmnsn_object *dmnsn_new_object(); +void dmnsn_delete_object(dmnsn_object *object); + #endif /* DIMENSION_OBJECT_H */ diff --git a/libdimension/dimension/sphere.h b/libdimension/dimension/sphere.h new file mode 100644 index 0000000..2547965 --- /dev/null +++ b/libdimension/dimension/sphere.h @@ -0,0 +1,31 @@ +/************************************************************************* + * Copyright (C) 2008 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 * + * . * + *************************************************************************/ + +#ifndef DIMENSION_SPHERE_H +#define DIMENSION_SPHERE_H + +/* + * A sphere object, of radius 1, centered at the origin. + */ + +dmnsn_object *dmnsn_new_sphere(); +void dmnsn_delete_sphere(dmnsn_object *sphere); + +#endif /* DIMENSION_SPHERE_H */ diff --git a/libdimension/object.c b/libdimension/object.c new file mode 100644 index 0000000..39064f3 --- /dev/null +++ b/libdimension/object.c @@ -0,0 +1,34 @@ +/************************************************************************* + * Copyright (C) 2008 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 * + * . * + *************************************************************************/ + +#include "dimension.h" +#include /* For malloc */ + +dmnsn_object * +dmnsn_new_object() +{ + return malloc(sizeof(dmnsn_object)); +} + +void +dmnsn_delete_object(dmnsn_object *object) +{ + free(object); +} diff --git a/libdimension/sphere.c b/libdimension/sphere.c new file mode 100644 index 0000000..4b99eaf --- /dev/null +++ b/libdimension/sphere.c @@ -0,0 +1,69 @@ +/************************************************************************* + * Copyright (C) 2008 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 * + * . * + *************************************************************************/ + +#include "dimension.h" +#include /* For malloc */ +#include /* For sqrt */ + +static dmnsn_array *dmnsn_sphere_intersections_fn(dmnsn_line line); +static int dmnsn_sphere_inside_fn(dmnsn_vector point); + +dmnsn_object * +dmnsn_new_sphere() +{ + dmnsn_object *sphere = dmnsn_new_object(); + sphere->intersections_fn = &dmnsn_sphere_intersections_fn; + sphere->inside_fn = &dmnsn_sphere_inside_fn; + return sphere; +} + +void +dmnsn_delete_sphere(dmnsn_object *sphere) +{ + dmnsn_delete_object(sphere); +} + +static dmnsn_array * +dmnsn_sphere_intersections_fn(dmnsn_line line) +{ + double a, b, c, t[2]; + dmnsn_array *array = dmnsn_new_array(sizeof(double)); + + // Solve (x0 + nx*t)^2 + (y0 + ny*t)^2 + (z0 + nz*t)^2 == 1 + + a = line.n.x*line.n.x + line.n.y*line.n.y + line.n.z*line.n.z; + b = 2.0*(line.n.x*line.x0.x + line.n.y*line.x0.y + line.n.z*line.x0.z); + c = line.x0.x*line.x0.x + line.x0.y*line.x0.y + line.x0.z*line.x0.z - 1.0; + + if (b*b - 4.0*a*c >= 0) { + t[0] = (-b + sqrt(b*b - 4.0*a*c))/(2*a); + t[1] = (-b - sqrt(b*b - 4.0*a*c))/(2*a); + dmnsn_array_set(array, 0, &t[0]); + dmnsn_array_set(array, 1, &t[1]); + } + + return array; +} + +static int +dmnsn_sphere_inside_fn(dmnsn_vector point) +{ + return sqrt(point.x*point.x + point.y*point.y + point.z*point.z) < 1.0; +} -- cgit v1.2.3