#version 430 core
in vec4 gColor;
in vec2 cenPosT;
in float gRadIn;
in float gRadOut;
in vec2 angles;
out vec4 fColor;
out float gl_FragDepth;

uniform float rotation;

void main()
{
  vec2 pos = gl_FragCoord.xy;
  float d = distance(pos,cenPosT);
  float dTest = max ( step(gRadOut/2,d)
                    , 1 - step(gRadIn/2,d)
                    );

  vec2 posDiff = pos - cenPosT;
  float sa = angles.x - rotation;
  vec2 sv = vec2 (-sin(sa), cos(sa));
  float saTest = dot(sv,posDiff) >= 0 ? 0 : 1;
  float ea = angles.y - rotation;
  vec2 ev = vec2 (-sin(ea), cos(ea));
  float eaTest = dot(ev,posDiff) <= 0 ? 0 : 1;
  float aTest = ea - sa < radians(180) ? max (saTest,eaTest) 
                                       : min (saTest,eaTest);

  float onArcTest = max(dTest,aTest); 

  gl_FragDepth = max(gl_FragCoord.z , onArcTest);
  fColor = gColor;
}