cesium/Source/Shaders/Materials/ElevationContourMaterial.js

CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.

//This file is automatically rebuilt by the Cesium build process.
define(function() {
    'use strict';
    return "#ifdef GL_OES_standard_derivatives\n\
    #extension GL_OES_standard_derivatives : enable\n\
#endif\n\
\n\
uniform vec4 color;\n\
uniform float spacing;\n\
uniform float width;\n\
\n\
czm_material czm_getMaterial(czm_materialInput materialInput)\n\
{\n\
    czm_material material = czm_getDefaultMaterial(materialInput);\n\
\n\
    float distanceToContour = mod(materialInput.height, spacing);\n\
\n\
#ifdef GL_OES_standard_derivatives\n\
    float dxc = abs(dFdx(materialInput.height));\n\
    float dyc = abs(dFdy(materialInput.height));\n\
    float dF = max(dxc, dyc) * width;\n\
    material.alpha = (distanceToContour < dF) ? 1.0 : 0.0;\n\
#else\n\
    material.alpha = (distanceToContour < (czm_resolutionScale * width)) ? 1.0 : 0.0;\n\
#endif\n\
\n\
    material.diffuse = color.rgb;\n\
\n\
    return material;\n\
}\n\
";
});