Hello,

I'd like to draw a circle segment with a variable thickness, that is, like a pie chart with a hole in the middle.
So far, I've been able to do it using strokes, like this:

Code:

void drawSegment( int x, int y, int rad1, int rad2, float a1, float a2 )
{
  arc( x, y, rad1*2, rad1*2, a1, a2 );
  line( x+cos(a2)*rad2, y+sin(a2)*rad2, x+cos(a2)*rad1, y+sin(a2)*rad1 );
  arc( x, y, rad2*2, rad2*2, a1, a2 );
  line( x+cos(a1)*rad1, y+sin(a1)*rad1, x+cos(a1)*rad2, y+sin(a1)*rad2 );  
}


void setup()
{
  size( 400, 400 );
  noFill();
  drawSegment( 200, 200, 80, 90, 0, (TWO_PI/24) );   
}
 

However, as you can see i'm not drawing correctly since the second arc, in order to follow the logical drawing sequence, should draw from angle2 to angle 1. This becomes evident when using a fill(). The reason I did it like this is because I can't draw an arc counterclockwise.

Any idea on how i could do this?

Thanks!

Yes, Noah, it was my first idea, but the base remark of protozoo is valid, somehow Processing's arc command misses the large-arc and sweep flags of SVG, that would allow a finer control of path.

Another way to do the intended goal, although convoluted and not usable on complex background, is to draw a full arc section in intended color, then a smaller in the background color.
In both cases, the outline can be drawn afterward...