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/model/finishes/phong.c | 69 +++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 libdimension/model/finishes/phong.c (limited to 'libdimension/model/finishes/phong.c') diff --git a/libdimension/model/finishes/phong.c b/libdimension/model/finishes/phong.c new file mode 100644 index 0000000..6b1b1e1 --- /dev/null +++ b/libdimension/model/finishes/phong.c @@ -0,0 +1,69 @@ +/************************************************************************* + * Copyright (C) 2010-2014 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 + * Phong highlights. + */ + +#include "dimension/model.h" +#include + +/// Phone specular type. +typedef struct dmnsn_phong { + dmnsn_specular specular; + double coeff; + double exp; +} dmnsn_phong; + +/// Phong specular highlight callback. +static dmnsn_color +dmnsn_phong_specular_fn(const dmnsn_specular *specular, + dmnsn_color light, dmnsn_color color, + dmnsn_vector ray, dmnsn_vector normal, + dmnsn_vector viewer) +{ + const dmnsn_phong *phong = (const dmnsn_phong *)specular; + + dmnsn_vector proj = dmnsn_vector_mul(2*dmnsn_vector_dot(ray, normal), normal); + dmnsn_vector reflected = dmnsn_vector_sub(proj, ray); + + double specular_factor = dmnsn_vector_dot(reflected, viewer); + if (specular_factor < 0.0) { + return dmnsn_black; + } + + specular_factor = pow(specular_factor, phong->exp); + return dmnsn_color_mul(phong->coeff*specular_factor, light); +} + +// A phong finish +dmnsn_specular * +dmnsn_new_phong(dmnsn_pool *pool, double coeff, double exp) +{ + dmnsn_phong *phong = DMNSN_PALLOC(pool, dmnsn_phong); + phong->coeff = coeff; + phong->exp = exp; + + dmnsn_specular *specular = &phong->specular; + dmnsn_init_specular(specular); + specular->specular_fn = dmnsn_phong_specular_fn; + return specular; +} -- cgit v1.2.3