varying vec2 v_pos; #pragma mapbox: define highp vec4 outline_color #pragma mapbox: define lowp float opacity void main() { #pragma mapbox: initialize highp vec4 outline_color #pragma mapbox: initialize lowp float opacity float dist = length(v_pos - gl_FragCoord.xy); float alpha = 1.0 - smoothstep(0.0, 1.0, dist); gl_FragColor = outline_color * (alpha * opacity); #ifdef OVERDRAW_INSPECTOR gl_FragColor = vec4(1.0); #endif }