uniform vec4 lightColor;
uniform vec4 darkColor;
uniform vec2 repeat;

czm_material czm_getMaterial(czm_materialInput materialInput)
{
    czm_material material = czm_getDefaultMaterial(materialInput);

    // From Stefan Gustavson's Procedural Textures in GLSL in OpenGL Insights
    float b = smoothstep(0.3, 0.32, length(fract(repeat * materialInput.st) - 0.5));  // 0.0 or 1.0

    vec4 color = mix(lightColor, darkColor, b);
    color = czm_gammaCorrect(color);
    material.diffuse = color.rgb;
    material.alpha = color.a;

    return material;
}