#version 450
#extension GL_ARB_separate_shader_objects : enable
#extension GL_ARB_shading_language_420pack : enable
#extension GL_EXT_nonuniform_qualifier : require

struct MatPropData
{
  vec4 color;
  int textureIndex;
  float alpha;
  vec3 beta;
};

layout(location = 0) in struct
{
  vec4 vertPos; // location 0
  vec2 uv; // location = 1
  vec4 normal; // location = 2

} In;

// material stuff
layout(location = 3) flat in struct
{
  uint eid;
  vec3 textColor;
} In2;



layout(set = 4, binding = 0) uniform sampler2D fontBitmap;

layout(location = 0) out vec4 color;
layout(location = 1) out uint outEntityID;

float median(float r, float g, float b) 
{
  return max(min(r, g), min(max(r, g), b));
}

void main()
{
  vec3 msd = texture (fontBitmap, In.uv).rgb;
  float sd = median (msd.r, msd.g, msd.b);
  float screenPxDistance = 2 * (sd - 0.5f);
  float opacity = clamp (screenPxDistance + 0.5f, 0.0f, 2.0f);

  vec4 fragColor = vec4 (1.0f);

  if (opacity > 0.02f && opacity < 1.9f)
  {
    fragColor = vec4(0.0f, 1.0f, 1.0f, 1.0f);
  }

  fragColor = mix(vec4(0.0f), vec4(In2.textColor, 1.0f), min (opacity, 1.0f));


  color = fragColor;
  outEntityID = In2.eid;
}