shader_type spatial;

render_mode cull_front, unshaded, depth_draw_never;

uniform vec4 outline_color : source_color;
uniform float outline_width = 4;

void vertex() {
  vec4 clip_position =
      PROJECTION_MATRIX * (MODELVIEW_MATRIX * vec4(VERTEX, 1.0));
  vec3 clip_normal =
      mat3(PROJECTION_MATRIX) * (mat3(MODELVIEW_MATRIX) * NORMAL);
  clip_position.xy += normalize(clip_normal.xy) / VIEWPORT_SIZE *
                      clip_position.w * outline_width;
  POSITION = clip_position;
}

void fragment() { ALBEDO = outline_color.rgb; }