paysages3d/src/experiments/bruneton/copyInscatterN.glsl

79 lines
2.5 KiB
GLSL

/**
* Precomputed Atmospheric Scattering
* Copyright (c) 2008 INRIA
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of the copyright holders nor the names of its
* 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 OWNER OR CONTRIBUTORS 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.
*/
/**
* Author: Eric Bruneton
*/
// adds deltaS into S (line 11 in algorithm 4.1)
uniform float r;
uniform vec4 dhdH;
uniform int layer;
uniform sampler3D deltaSSampler;
#ifdef _VERTEX_
void main() {
gl_Position = gl_Vertex;
}
#endif
#ifdef _GEOMETRY_
#extension GL_EXT_geometry_shader4 : enable
void main() {
gl_Position = gl_PositionIn[0];
gl_Layer = layer;
EmitVertex();
gl_Position = gl_PositionIn[1];
gl_Layer = layer;
EmitVertex();
gl_Position = gl_PositionIn[2];
gl_Layer = layer;
EmitVertex();
EndPrimitive();
}
#endif
#ifdef _FRAGMENT_
void main() {
float mu, muS, nu;
getMuMuSNu(r, dhdH, mu, muS, nu);
vec3 uvw = vec3(gl_FragCoord.xy, float(layer) + 0.5) / vec3(ivec3(RES_MU_S * RES_NU, RES_MU, RES_R));
gl_FragColor = vec4(texture3D(deltaSSampler, uvw).rgb / phaseFunctionR(nu), 0.0);
}
#endif