#version 150 core

uniform sampler2D Texture;
uniform vec4 Fill;

in vec2  TextureCoord;

out vec4 FragColor;

#define MEDIAN(x, y, z) max(min(x, y), min(max(x, y), z))

void main() {
  vec4 msd = texture2D(Texture, TextureCoord);

  // float sd = MEDIAN(msd.r, msd.g, msd.b);
  // float fw = fwidth(sd);
  // float alpha = smoothstep(0.5 - fw, 0.5 + fw, sd);

  float sd = msd.a;
  float fw = 6 / 16.0;
  float alpha = smoothstep(0.5 - fw, 0.5 + fw, sd);

  // float alpha = msd.a;

  FragColor = Fill * alpha;
}