From 47c128a3106206038e45eb8b8abf6c712f29ac14 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Wed, 1 Jul 2009 04:45:23 +0000 Subject: New C++ dmnsn_camera* wrapper. --- libdimension/cameras.c | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 libdimension/cameras.c (limited to 'libdimension/cameras.c') diff --git a/libdimension/cameras.c b/libdimension/cameras.c new file mode 100644 index 0000000..c6dcf59 --- /dev/null +++ b/libdimension/cameras.c @@ -0,0 +1,80 @@ +/************************************************************************* + * 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" + +/* + * Perspective camera + */ + +/* Perspective camera ray callback */ +static dmnsn_line dmnsn_perspective_camera_ray_fn(const dmnsn_camera *camera, + const dmnsn_canvas *canvas, + unsigned int x, + unsigned int y); + +/* Create a new perspective camera. Rays are aimed from the origin to a screen + located on the z = 1 frame, from (-0.5, -0.5) to (0.5, 0.5). Rays are then + transformed by the matrix `trans'. */ +dmnsn_camera * +dmnsn_new_perspective_camera(dmnsn_matrix trans) +{ + dmnsn_camera *camera = dmnsn_new_camera(); + if (camera) { + camera->ray_fn = &dmnsn_perspective_camera_ray_fn; + + camera->ptr = malloc(sizeof(dmnsn_matrix)); + if (!camera->ptr) { + dmnsn_delete_camera(camera); + return NULL; + } + *((dmnsn_matrix*)camera->ptr) = trans; + } + return camera; +} + +/* Delete a perspective camera */ +void +dmnsn_delete_perspective_camera(dmnsn_camera *camera) +{ + if (camera) { + free(camera->ptr); + dmnsn_delete_camera(camera); + } +} + +static dmnsn_line +dmnsn_perspective_camera_ray_fn(const dmnsn_camera *camera, + const dmnsn_canvas *canvas, + unsigned int x, unsigned int y) +{ + dmnsn_matrix *trans = (dmnsn_matrix *)camera->ptr; + dmnsn_line l; + + /* Rays originate at the origin, oddly enough */ + l.x0 = dmnsn_vector_construct(0.0, 0.0, 0.0); + + /* Aim at the z = 1 plane */ + l.n.x = ((double)x)/(canvas->x - 1) - 0.5; + l.n.y = ((double)y)/(canvas->y - 1) - 0.5; + l.n.z = 1.0; + + return dmnsn_matrix_line_mul(*trans, l); +} -- cgit v1.2.3