mrxz

uniform vec3 color;
uniform vec3 borderColor;
uniform float borderWidth;
varying vec2 vUv;

// Technique based on Inigo Quilez's 'Analytic checkers pattern filtering'
// https://iquilezles.org/articles/checkerfiltering/
float border(in vec2 uv, in vec2 ddx, in vec2 ddy) {
	// filter kernel
	vec2 w = max(abs(ddx), abs(ddy)) + 0.001;