From 4e2a6e40a77068492e3b63b84a18d0cc7f003fb7 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Wed, 6 Jan 2010 13:43:14 -0500 Subject: Split up objects, finishes, pigments, lights, cameras, etc. --- libdimension/phong.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 libdimension/phong.c (limited to 'libdimension/phong.c') diff --git a/libdimension/phong.c b/libdimension/phong.c new file mode 100644 index 0000000..815885f --- /dev/null +++ b/libdimension/phong.c @@ -0,0 +1,67 @@ +/************************************************************************* + * Copyright (C) 2009 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 + +/* + * Phong finish + */ + +static dmnsn_color +dmnsn_phong_finish_fn(const dmnsn_finish *finish, + dmnsn_color light, dmnsn_color color, + dmnsn_vector ray, dmnsn_vector normal, + dmnsn_vector viewer) +{ + double *params = finish->ptr; + + double specular = params[0]; + double exp = params[1]; + + dmnsn_vector proj = dmnsn_vector_mul(2*dmnsn_vector_dot(ray, normal), normal); + dmnsn_vector reflected = dmnsn_vector_sub(proj, ray); + + double specular_factor = pow(dmnsn_vector_dot(reflected, viewer), exp); + return dmnsn_color_mul(specular*specular_factor, light); +} + +/* A phong finish */ +dmnsn_finish * +dmnsn_new_phong_finish(double specular, double exp) +{ + dmnsn_finish *finish = dmnsn_new_finish(); + if (finish) { + double *params = malloc(2*sizeof(double)); + if (!params) { + dmnsn_delete_finish(finish); + return NULL; + } + + params[0] = specular; + params[1] = exp; + + finish->ptr = params; + finish->finish_fn = &dmnsn_phong_finish_fn; + finish->free_fn = &free; + } + return finish; +} -- cgit v1.2.3