overte/interface/resources/shaders/metavoxel_heightfield_shadow_map.frag
2014-08-15 16:13:47 -07:00

37 lines
1.3 KiB
GLSL

#version 120
//
// metavoxel_heightfield.frag
// fragment shader
//
// Created by Andrzej Kapolka on 7/28/14.
// Copyright 2014 High Fidelity, Inc.
//
// Distributed under the Apache License, Version 2.0.
// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//
// the diffuse texture
uniform sampler2D diffuseMap;
// the shadow texture
uniform sampler2DShadow shadowMap;
// the inverse of the size of the shadow map
const float shadowScale = 1.0 / 2048.0;
// the interpolated normal
varying vec4 normal;
void main(void) {
// compute the base color based on OpenGL lighting model
float diffuse = dot(normalize(normal), gl_LightSource[0].position);
float facingLight = step(0.0, diffuse) * 0.25 *
(shadow2D(shadowMap, gl_TexCoord[1].stp + vec3(-shadowScale, -shadowScale, 0.0)).r +
shadow2D(shadowMap, gl_TexCoord[1].stp + vec3(-shadowScale, shadowScale, 0.0)).r +
shadow2D(shadowMap, gl_TexCoord[1].stp + vec3(shadowScale, -shadowScale, 0.0)).r +
shadow2D(shadowMap, gl_TexCoord[1].stp + vec3(shadowScale, shadowScale, 0.0)).r);
vec4 base = gl_Color * (gl_FrontLightModelProduct.sceneColor + gl_FrontLightProduct[0].ambient +
gl_FrontLightProduct[0].diffuse * (diffuse * facingLight));
gl_FragColor = base * texture2D(diffuseMap, gl_TexCoord[0].st);
}