Integrate skylight model. Work in progress.
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extern/skylight/ArHosekSkyModel.c
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extern/skylight/ArHosekSkyModel.c
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/*
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This source is published under the following 3-clause BSD license.
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Copyright (c) 2012, Lukas Hosek and Alexander Wilkie
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All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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* None of the names of the contributors may be used to endorse or promote
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products derived from this software without specific prior written
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permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
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DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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/* ============================================================================
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This file is part of a sample implementation of the analytical skylight model
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presented in the SIGGRAPH 2012 paper
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"An Analytic Model for Full Spectral Sky-Dome Radiance"
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by
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Lukas Hosek and Alexander Wilkie
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Charles University in Prague, Czech Republic
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Version: 1.0, May 11th, 2012
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Please visit http://cgg.mff.cuni.cz/projects/SkylightModelling/ to check if
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an updated version of this code has been published!
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============================================================================ */
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/*
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All instructions on how to use this code are to be found in the accompanying
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header file.
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*/
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#include "ArHosekSkyModel.h"
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#include "ArHosekSkyModelData.h"
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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// Some macro definitions that occur elsewhere in ART, and that have to be
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// replicated to make this a stand-alone module.
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#ifndef NIL
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#define NIL 0
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#endif
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#ifndef MATH_PI
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#define MATH_PI 3.141593
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#endif
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#ifndef ALLOC
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#define ALLOC(_struct) ((_struct *)malloc(sizeof(_struct)))
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#endif
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// internal definitions
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typedef double *ArHosekSkyModel_Dataset;
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typedef double *ArHosekSkyModel_Radiance_Dataset;
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// internal functions
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void ArHosekSkyModel_CookConfiguration(
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ArHosekSkyModel_Dataset dataset,
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ArHosekSkyModelConfiguration config,
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double turbidity,
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double albedo,
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double solar_elevation
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)
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{
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double * elev_matrix;
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int int_turbidity = turbidity;
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double turbidity_rem = turbidity - (double)int_turbidity;
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solar_elevation = pow(solar_elevation / (MATH_PI / 2.0), (1.0 / 3.0));
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// alb 0 low turb
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elev_matrix = dataset + ( 9 * 6 * (int_turbidity-1) );
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for( unsigned int i = 0; i < 9; ++i )
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{
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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config[i] =
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(1.0-albedo) * (1.0 - turbidity_rem)
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* ( pow(1.0-solar_elevation, 5.0) * elev_matrix[i] +
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5.0 * pow(1.0-solar_elevation, 4.0) * solar_elevation * elev_matrix[i+9] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[i+18] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[i+27] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[i+36] +
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pow(solar_elevation, 5.0) * elev_matrix[i+45]);
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}
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// alb 1 low turb
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elev_matrix = dataset + (9*6*10 + 9*6*(int_turbidity-1));
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for(unsigned int i = 0; i < 9; ++i)
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{
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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config[i] +=
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(albedo) * (1.0 - turbidity_rem)
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* ( pow(1.0-solar_elevation, 5.0) * elev_matrix[i] +
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5.0 * pow(1.0-solar_elevation, 4.0) * solar_elevation * elev_matrix[i+9] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[i+18] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[i+27] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[i+36] +
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pow(solar_elevation, 5.0) * elev_matrix[i+45]);
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}
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if(int_turbidity == 10)
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return;
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// alb 0 high turb
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elev_matrix = dataset + (9*6*(int_turbidity));
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for(unsigned int i = 0; i < 9; ++i)
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{
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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config[i] +=
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(1.0-albedo) * (turbidity_rem)
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* ( pow(1.0-solar_elevation, 5.0) * elev_matrix[i] +
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5.0 * pow(1.0-solar_elevation, 4.0) * solar_elevation * elev_matrix[i+9] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[i+18] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[i+27] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[i+36] +
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pow(solar_elevation, 5.0) * elev_matrix[i+45]);
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}
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// alb 1 high turb
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elev_matrix = dataset + (9*6*10 + 9*6*(int_turbidity));
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for(unsigned int i = 0; i < 9; ++i)
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{
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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config[i] +=
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(albedo) * (turbidity_rem)
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* ( pow(1.0-solar_elevation, 5.0) * elev_matrix[i] +
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5.0 * pow(1.0-solar_elevation, 4.0) * solar_elevation * elev_matrix[i+9] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[i+18] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[i+27] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[i+36] +
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pow(solar_elevation, 5.0) * elev_matrix[i+45]);
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}
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}
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double ArHosekSkyModel_CookRadianceConfiguration(
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ArHosekSkyModel_Radiance_Dataset dataset,
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double turbidity,
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double albedo,
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double solar_elevation
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)
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{
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double* elev_matrix;
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int int_turbidity = turbidity;
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double turbidity_rem = turbidity - (double)int_turbidity;
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double res;
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solar_elevation = pow(solar_elevation / (M_PI / 2.0), (1.0 / 3.0));
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// alb 0 low turb
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elev_matrix = dataset + (6*(int_turbidity-1));
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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res = (1.0-albedo) * (1.0 - turbidity_rem) *
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( pow(1.0-solar_elevation, 5.0) * elev_matrix[0] +
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5.0*pow(1.0-solar_elevation, 4.0)*solar_elevation * elev_matrix[1] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[2] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[3] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[4] +
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pow(solar_elevation, 5.0) * elev_matrix[5]);
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// alb 1 low turb
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elev_matrix = dataset + (6*10 + 6*(int_turbidity-1));
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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res += (albedo) * (1.0 - turbidity_rem) *
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( pow(1.0-solar_elevation, 5.0) * elev_matrix[0] +
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5.0*pow(1.0-solar_elevation, 4.0)*solar_elevation * elev_matrix[1] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[2] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[3] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[4] +
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pow(solar_elevation, 5.0) * elev_matrix[5]);
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if(int_turbidity == 10)
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return res;
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// alb 0 high turb
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elev_matrix = dataset + (6*(int_turbidity));
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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res += (1.0-albedo) * (turbidity_rem) *
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( pow(1.0-solar_elevation, 5.0) * elev_matrix[0] +
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5.0*pow(1.0-solar_elevation, 4.0)*solar_elevation * elev_matrix[1] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[2] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[3] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[4] +
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pow(solar_elevation, 5.0) * elev_matrix[5]);
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// alb 1 high turb
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elev_matrix = dataset + (6*10 + 6*(int_turbidity));
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//(1-t).^3* A1 + 3*(1-t).^2.*t * A2 + 3*(1-t) .* t .^ 2 * A3 + t.^3 * A4;
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res += (albedo) * (turbidity_rem) *
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( pow(1.0-solar_elevation, 5.0) * elev_matrix[0] +
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5.0*pow(1.0-solar_elevation, 4.0)*solar_elevation * elev_matrix[1] +
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10.0*pow(1.0-solar_elevation, 3.0)*pow(solar_elevation, 2.0) * elev_matrix[2] +
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10.0*pow(1.0-solar_elevation, 2.0)*pow(solar_elevation, 3.0) * elev_matrix[3] +
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5.0*(1.0-solar_elevation)*pow(solar_elevation, 4.0) * elev_matrix[4] +
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pow(solar_elevation, 5.0) * elev_matrix[5]);
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return res;
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}
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double ArHosekSkyModel_GetRadianceInternal(
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ArHosekSkyModelConfiguration configuration,
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double theta,
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double gamma
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)
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{
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const double expM = exp(configuration[4] * gamma);
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const double rayM = cos(gamma)*cos(gamma);
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const double mieM = (1.0 + cos(gamma)*cos(gamma)) / pow((1.0 + configuration[8]*configuration[8] - 2.0*configuration[8]*cos(gamma)), 1.5);
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const double zenith = sqrt(cos(theta));
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return (1.0 + configuration[0] * exp(configuration[1] / (cos(theta) + 0.01))) *
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(configuration[2] + configuration[3] * expM + configuration[5] * rayM + configuration[6] * mieM + configuration[7] * zenith);
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}
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// spectral version
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ArHosekSkyModelState * arhosekskymodelstate_alloc_init(
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const double turbidity,
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const double albedo,
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const double elevation
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)
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{
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ArHosekSkyModelState * state = ALLOC(ArHosekSkyModelState);
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for( unsigned int wl = 0; wl < 11; ++wl )
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{
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ArHosekSkyModel_CookConfiguration(
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datasets[wl],
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state->configs[wl],
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turbidity,
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albedo,
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elevation
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);
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state->radiances[wl] =
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ArHosekSkyModel_CookRadianceConfiguration(
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datasetsRad[wl],
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turbidity,
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albedo,
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elevation
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);
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}
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return state;
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}
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void arhosekskymodelstate_free(
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ArHosekSkyModelState * state
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)
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{
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free(state);
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}
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double arhosekskymodel_radiance(
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ArHosekSkyModelState * state,
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double theta,
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double gamma,
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double wavelength
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)
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{
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int low_wl = (wavelength - 320.0 ) / 40.0;
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double interp = fmod((wavelength - 320.0 ) / 40.0, 1.0);
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double val_low =
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ArHosekSkyModel_GetRadianceInternal(
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state->configs[low_wl],
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theta,
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gamma
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)
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* state->radiances[low_wl];
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if(interp < 1e-6)
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return val_low;
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double result =
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(1.0 - interp)
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* val_low
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+ interp
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* ArHosekSkyModel_GetRadianceInternal(
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state->configs[low_wl+1],
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theta,
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gamma
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)
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* state->radiances[low_wl+1];
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return result;
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}
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// xyz version
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ArHosekXYZSkyModelState * arhosek_xyz_skymodelstate_alloc_init(
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const double turbidity,
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const double albedo,
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const double elevation
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)
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{
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|
ArHosekXYZSkyModelState * state = ALLOC(ArHosekXYZSkyModelState);
|
||||||
|
|
||||||
|
for( unsigned int channel = 0; channel < 3; ++channel )
|
||||||
|
{
|
||||||
|
ArHosekSkyModel_CookConfiguration(
|
||||||
|
datasetsXYZ[channel],
|
||||||
|
state->configs[channel],
|
||||||
|
turbidity,
|
||||||
|
albedo,
|
||||||
|
elevation
|
||||||
|
);
|
||||||
|
|
||||||
|
state->radiances[channel] =
|
||||||
|
ArHosekSkyModel_CookRadianceConfiguration(
|
||||||
|
datasetsXYZRad[channel],
|
||||||
|
turbidity,
|
||||||
|
albedo,
|
||||||
|
elevation
|
||||||
|
);
|
||||||
|
}
|
||||||
|
|
||||||
|
return state;
|
||||||
|
}
|
||||||
|
|
||||||
|
void arhosek_xyz_skymodelstate_free(
|
||||||
|
ArHosekXYZSkyModelState * state
|
||||||
|
)
|
||||||
|
{
|
||||||
|
free(state);
|
||||||
|
}
|
||||||
|
|
||||||
|
double arhosek_xyz_skymodel_radiance(
|
||||||
|
ArHosekXYZSkyModelState * state,
|
||||||
|
double theta,
|
||||||
|
double gamma,
|
||||||
|
int channel
|
||||||
|
)
|
||||||
|
{
|
||||||
|
return
|
||||||
|
ArHosekSkyModel_GetRadianceInternal(
|
||||||
|
state->configs[channel],
|
||||||
|
theta,
|
||||||
|
gamma
|
||||||
|
)
|
||||||
|
* state->radiances[channel];
|
||||||
|
}
|
||||||
190
extern/skylight/ArHosekSkyModel.h
vendored
Normal file
190
extern/skylight/ArHosekSkyModel.h
vendored
Normal file
@ -0,0 +1,190 @@
|
|||||||
|
/*
|
||||||
|
This source is published under the following 3-clause BSD license.
|
||||||
|
|
||||||
|
Copyright (c) 2012, Lukas Hosek and Alexander Wilkie
|
||||||
|
All rights reserved.
|
||||||
|
|
||||||
|
Redistribution and use in source and binary forms, with or without
|
||||||
|
modification, are permitted provided that the following conditions are met:
|
||||||
|
|
||||||
|
* Redistributions of source code must retain the above copyright
|
||||||
|
notice, this list of conditions and the following disclaimer.
|
||||||
|
* Redistributions in binary form must reproduce the above copyright
|
||||||
|
notice, this list of conditions and the following disclaimer in the
|
||||||
|
documentation and/or other materials provided with the distribution.
|
||||||
|
* None of the names of the contributors may be used to endorse or promote
|
||||||
|
products derived from this software without specific prior written
|
||||||
|
permission.
|
||||||
|
|
||||||
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
|
||||||
|
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
||||||
|
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||||
|
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
|
||||||
|
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
||||||
|
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
||||||
|
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||||
|
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||||||
|
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
||||||
|
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||||
|
*/
|
||||||
|
|
||||||
|
|
||||||
|
/* ============================================================================
|
||||||
|
|
||||||
|
This file is part of a sample implementation of the analytical skylight model
|
||||||
|
presented in the SIGGRAPH 2012 paper
|
||||||
|
|
||||||
|
|
||||||
|
"An Analytic Model for Full Spectral Sky-Dome Radiance"
|
||||||
|
|
||||||
|
by
|
||||||
|
|
||||||
|
Lukas Hosek and Alexander Wilkie
|
||||||
|
Charles University in Prague, Czech Republic
|
||||||
|
|
||||||
|
|
||||||
|
Version: 1.0, May 11th, 2012
|
||||||
|
|
||||||
|
|
||||||
|
Please visit http://cgg.mff.cuni.cz/projects/SkylightModelling/ to check if
|
||||||
|
an updated version of this code has been published!
|
||||||
|
|
||||||
|
============================================================================ */
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
|
||||||
|
This code is taken from ART, a rendering research system written in a
|
||||||
|
mix of C99 / Objective C. Since ART is not a small system and is intended to
|
||||||
|
be inter-operable with other libraries, and since C does not have namespaces,
|
||||||
|
the structures and functions in ART all have to have the somewhat wordy
|
||||||
|
canonical names that begin with Ar.../ar..., like those seen in this example.
|
||||||
|
|
||||||
|
Usage information:
|
||||||
|
==================
|
||||||
|
|
||||||
|
|
||||||
|
Model initialisation
|
||||||
|
--------------------
|
||||||
|
|
||||||
|
A separate ArHosekSkyModelState has to be maintained for each spectral
|
||||||
|
band you want to use the model for. So in a renderer with num_channels
|
||||||
|
bands, you would need something like
|
||||||
|
|
||||||
|
ArHosekSkyModelState * skymodel_state[num_channels];
|
||||||
|
|
||||||
|
You then have to allocate these states. In the following code snippet, we
|
||||||
|
assume that "albedo" is defined as
|
||||||
|
|
||||||
|
double albedo[num_channels];
|
||||||
|
|
||||||
|
with a ground albedo value between [0,1] for each channel. The solar elevation
|
||||||
|
is given in radians.
|
||||||
|
|
||||||
|
for ( unsigned int i = 0; i < num_channels; i++ )
|
||||||
|
skymodel_state[i] =
|
||||||
|
arhosekskymodelstate_alloc_init(
|
||||||
|
turbidity,
|
||||||
|
albedo[i],
|
||||||
|
solarElevation
|
||||||
|
);
|
||||||
|
|
||||||
|
|
||||||
|
Using the model to generate skydome samples
|
||||||
|
-------------------------------------------
|
||||||
|
|
||||||
|
Generating a skydome radiance spectrum "skydome_result" for a given location
|
||||||
|
on the skydome determined via the angles theta and gamma works as follows:
|
||||||
|
|
||||||
|
double skydome_result[num_channels];
|
||||||
|
|
||||||
|
for ( unsigned int i = 0; i < num_channels; i++ )
|
||||||
|
skydome_result[i] =
|
||||||
|
arhosekskymodel_radiance(
|
||||||
|
skymodel_state[i],
|
||||||
|
theta,
|
||||||
|
gamma,
|
||||||
|
channel_center[i]
|
||||||
|
);
|
||||||
|
|
||||||
|
The variable "channel_center" is assumed to hold the channel center wavelengths
|
||||||
|
for each of the num_channels samples of the spectrum we are building.
|
||||||
|
|
||||||
|
|
||||||
|
Cleanup after use
|
||||||
|
-----------------
|
||||||
|
|
||||||
|
After rendering is complete, the content of the sky model states should be
|
||||||
|
disposed of via
|
||||||
|
|
||||||
|
for ( unsigned int i = 0; i < num_channels; i++ )
|
||||||
|
arhosekskymodelstate_free( skymodel_state[i] );
|
||||||
|
|
||||||
|
|
||||||
|
CIE XYZ Version of the Model
|
||||||
|
----------------------------
|
||||||
|
|
||||||
|
Usage of the CIE XYZ version of the model is exactly the same, except that
|
||||||
|
num_channels is of course always 3, and that ArHosekXYZSkyModelState and
|
||||||
|
arhosek_xyz_skymodel_radiance() have to be used instead of their spectral
|
||||||
|
counterparts.
|
||||||
|
|
||||||
|
*/
|
||||||
|
|
||||||
|
typedef double ArHosekSkyModelConfiguration[9];
|
||||||
|
|
||||||
|
|
||||||
|
// Spectral version of the model
|
||||||
|
|
||||||
|
|
||||||
|
typedef struct ArHosekSkyModelState
|
||||||
|
{
|
||||||
|
ArHosekSkyModelConfiguration configs[11];
|
||||||
|
double radiances[11];
|
||||||
|
}
|
||||||
|
ArHosekSkyModelState;
|
||||||
|
|
||||||
|
ArHosekSkyModelState * arhosekskymodelstate_alloc_init(
|
||||||
|
const double turbidity,
|
||||||
|
const double albedo,
|
||||||
|
const double elevation
|
||||||
|
);
|
||||||
|
|
||||||
|
void arhosekskymodelstate_free(
|
||||||
|
ArHosekSkyModelState * state
|
||||||
|
);
|
||||||
|
|
||||||
|
double arhosekskymodel_radiance(
|
||||||
|
ArHosekSkyModelState * state,
|
||||||
|
double theta,
|
||||||
|
double gamma,
|
||||||
|
double wavelength
|
||||||
|
);
|
||||||
|
|
||||||
|
|
||||||
|
// CIE XYZ version
|
||||||
|
|
||||||
|
|
||||||
|
typedef struct ArHosekXYZSkyModelState
|
||||||
|
{
|
||||||
|
ArHosekSkyModelConfiguration configs[3];
|
||||||
|
double radiances[3];
|
||||||
|
}
|
||||||
|
ArHosekXYZSkyModelState;
|
||||||
|
|
||||||
|
ArHosekXYZSkyModelState * arhosek_xyz_skymodelstate_alloc_init(
|
||||||
|
const double turbidity,
|
||||||
|
const double albedo,
|
||||||
|
const double elevation
|
||||||
|
);
|
||||||
|
|
||||||
|
void arhosek_xyz_skymodelstate_free(
|
||||||
|
ArHosekXYZSkyModelState * state
|
||||||
|
);
|
||||||
|
|
||||||
|
double arhosek_xyz_skymodel_radiance(
|
||||||
|
ArHosekXYZSkyModelState * state,
|
||||||
|
double theta,
|
||||||
|
double gamma,
|
||||||
|
int channel
|
||||||
|
);
|
||||||
17579
extern/skylight/ArHosekSkyModelData.h
vendored
Normal file
17579
extern/skylight/ArHosekSkyModelData.h
vendored
Normal file
File diff suppressed because it is too large
Load Diff
33
extern/skylight/README.txt
vendored
Normal file
33
extern/skylight/README.txt
vendored
Normal file
@ -0,0 +1,33 @@
|
|||||||
|
The files in this archive are a sample implementation of the analytical
|
||||||
|
skylight model presented in the SIGGRAPH 2012 paper
|
||||||
|
|
||||||
|
|
||||||
|
"An Analytic Model for Full Spectral Sky-Dome Radiance"
|
||||||
|
|
||||||
|
by
|
||||||
|
|
||||||
|
Lukas Hosek and Alexander Wilkie
|
||||||
|
Charles University in Prague, Czech Republic
|
||||||
|
|
||||||
|
|
||||||
|
Version: 1.0, May 11th, 2012
|
||||||
|
|
||||||
|
|
||||||
|
Please visit http://cgg.mff.cuni.cz/projects/SkylightModelling/ to check if
|
||||||
|
an updated version of this code has been published!
|
||||||
|
|
||||||
|
|
||||||
|
This archive contains the following files:
|
||||||
|
|
||||||
|
README.txt This file.
|
||||||
|
|
||||||
|
ArHosekSkyModel.h Header file for the reference functions. Their
|
||||||
|
usage is explained there, and sample code for
|
||||||
|
calling them is given.
|
||||||
|
|
||||||
|
ArHosekSkyModel.c Implementation of the functions.
|
||||||
|
|
||||||
|
ArHosekSkyModelData.h Coefficient data.
|
||||||
|
|
||||||
|
Please note that the source files are in C99, so that when e.g. compiling this
|
||||||
|
code with gcc, you have to add the "-std=c99" or "-std=gnu99" flags.
|
||||||
@ -814,3 +814,52 @@ void CubeSurface::toGamma(float gamma)
|
|||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
||||||
|
#if 0
|
||||||
|
// @@ Provide solar azimuth.
|
||||||
|
#include "ArHoseSkyModel.h"
|
||||||
|
void CubeSurface::sky(float turbidity, float albedo[3], float solarElevation) {
|
||||||
|
|
||||||
|
ArHosekSkyModelState * skymodel_state[3];
|
||||||
|
|
||||||
|
for (int i = 0; i < num_channels; i++) {
|
||||||
|
skymodel_state[i] = arhosekskymodelstate_alloc_init(turbidity, albedo[i], solarElevation);
|
||||||
|
}
|
||||||
|
|
||||||
|
// 700 nm (red), 546.1 nm (green) and 435.8 nm (blue).
|
||||||
|
float channel_center[3] = {
|
||||||
|
700, // Red 620–740,
|
||||||
|
546.1, // Green 520–570,
|
||||||
|
435.8, // Blue 450–490,
|
||||||
|
};
|
||||||
|
|
||||||
|
// @@ For each pixel:
|
||||||
|
// What's the channel center for the RGB model?
|
||||||
|
double skydome_result[3];
|
||||||
|
for (unsigned int i = 0; i < num_channels; i++) {
|
||||||
|
skydome_result[i] = arhosekskymodel_radiance(skymodel_state[i], theta, gamma, channel_center[i]);
|
||||||
|
}
|
||||||
|
|
||||||
|
for (int i = 0; i < num_channels; i++) {
|
||||||
|
arhosek_skymodelstate_free(skymodel_state[i]);
|
||||||
|
}
|
||||||
|
|
||||||
|
/*
|
||||||
|
ArHosekXYZSkyModelState * skymodel_state[3];
|
||||||
|
|
||||||
|
for (int i = 0; i < num_channels; i++) {
|
||||||
|
skymodel_state[i] = arhosek_xyz_skymodelstate_alloc_init(turbidity, albedo[i], solarElevation);
|
||||||
|
}
|
||||||
|
|
||||||
|
// @@ For each pixel.
|
||||||
|
double skydome_result[3];
|
||||||
|
for (unsigned int i = 0; i < num_channels; i++) {
|
||||||
|
skydome_result[i] = arhosek_xyz_skymodel_radiance(skymodel_state[i], theta, gamma, i);
|
||||||
|
}
|
||||||
|
|
||||||
|
for (int i = 0; i < num_channels; i++) {
|
||||||
|
arhosek_xyz_skymodelstate_free(skymodel_state[i]);
|
||||||
|
}
|
||||||
|
*/
|
||||||
|
}
|
||||||
|
#endif
|
||||||
Loading…
Reference in New Issue
Block a user