overte/interface/resources/shaders/metavoxel_heightfield_splat.frag

30 lines
923 B
GLSL

#version 120
//
// metavoxel_heightfield_splat.frag
// fragment shader
//
// Created by Andrzej Kapolka on 8/20/14.
// 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 number of splats per pass
const int SPLAT_COUNT = 4;
// the splat textures
uniform sampler2D diffuseMaps[SPLAT_COUNT];
// alpha values for the four splat textures
varying vec4 alphaValues;
void main(void) {
// blend the splat textures
gl_FragColor = vec4(gl_Color.rgb, step(1.0, gl_Color.a + 1.0 / 512.0)) *
(texture2D(diffuseMaps[0], gl_TexCoord[0].st) * alphaValues.x +
texture2D(diffuseMaps[1], gl_TexCoord[1].st) * alphaValues.y +
texture2D(diffuseMaps[2], gl_TexCoord[2].st) * alphaValues.z +
texture2D(diffuseMaps[3], gl_TexCoord[3].st) * alphaValues.w);
}