Result from fillPolygon is sometimes incorrect for concave polygons

[JohnDeptuch]

When I run the following the polygon is filled incorrectly.

import 'dart:io';
import 'package:image/image.dart';
 
void main() {
  final i0 = Image(width: 200, height: 200);
 
  final vertices = <Point>[
    Point(50, 50),
    Point(50, 150),
    Point(150, 150),
    Point(150, 50),
    Point(100, 100),
  ];
 
  fillPolygon(i0, vertices: vertices, color: ColorRgb8(176, 0, 0));
  drawPolygon(i0, vertices: vertices, color: ColorRgb8(0, 255, 0));
  File('fillpolygon.png')
    ..createSync()
    ..writeAsBytesSync(encodePng(i0));
}

[brendan-duncan]

Yeah, sorry, the drawing functions are pretty rudimentary. The fillPolgon doesn't support concave polygons. I can see about doing a proper fillPolygon when I get a chance.

[brendan-duncan]

I had a few minutes, so I rewrote fillPolygon to use a ray-cast fill method that can better handle complex concave polygons.

[JohnDeptuch]

It's now working for me. Thanks for the fast response.