transbeam/resources/transbeam-common.asy

struct transbeamPrefs {
  real triangleRadius;
  real borderInset;
  real circleRadius;
  real bigBeamRadius;
  real smallBeamRadius;
  int beamCount;
  real beamAngle;
  real starterBeamAngle;
}

pen transBlue = rgb("55cdfc");
pen transPink = rgb("f7a8b8");

pen bigBeamColor = transPink;
pen smallBeamColor = transBlue;

path borderTriangle = dir(90)--dir(210)--dir(330)--cycle;

void drawTransbeam(transbeamPrefs prefs) {
  unravel prefs;

  path outerBorder = scale(triangleRadius)*borderTriangle;
  fill(outerBorder, white);

  path beam(real angle, real innerRadius, real outerRadius) {
    return arc((0,0), outerRadius, angle/2, -angle/2)--arc((0,0), innerRadius, -angle/2, angle/2)--cycle;
  }

  path bigBeam = beam(beamAngle, circleRadius, bigBeamRadius);
  path smallBeam = beam(beamAngle, circleRadius, smallBeamRadius);

  for (int i = 0; i < beamCount; ++i) {
    if (i > 0) {
      fill(rotate(360*i/beamCount)*bigBeam, bigBeamColor);
    }
    fill(rotate(360*(i+0.5)/beamCount)*smallBeam, smallBeamColor);
  }

  pair starterBeamTrianglePoint(real angle) {
    pair circlePoint = circleRadius*dir(angle);
    return intersectionpoint(circlePoint--(circlePoint+(triangleRadius,0)), outerBorder);
  }

  fill(starterBeamTrianglePoint(-starterBeamAngle/2)--arc((0,0), circleRadius, -starterBeamAngle/2, starterBeamAngle/2)--starterBeamTrianglePoint(starterBeamAngle/2)--cycle, bigBeamColor);

  draw(outerBorder, transPink+(2*borderInset));
  draw(scale(triangleRadius-borderInset)*borderTriangle, transBlue+borderInset);
}