Fixed polygon filling

examples/glaggle/main.go

@@ -6,14 +6,25 @@ import "image/png"
 import "git.tebibyte.media/tomo/ggfx"
 
 func main () {
-	img := image.NewRGBA(image.Rect(0, 0, 800, 600))
+	img := image.NewRGBA(image.Rect(0, 0, 300, 300))
 	canvas := ggfx.Image[uint8] {
 		Pix:    img.Pix,
 		Stride: img.Stride,
 		Bounds: img.Rect,
 		Width:  4,
 	}
-	canvas.FillRectangle([]uint8 { 255, 0, 0, 255 }, image.Rect(7, 4, 34, 78))
+	black := []uint8 { 0,   0, 0, 255 }
+	red   := []uint8 { 255, 0, 0, 255 }
+	canvas.FillPolygon (
+		black,
+		image.Pt(10, 10),
+		image.Pt(70, 50),
+		image.Pt(20, 70))
+	canvas.StrokePolygon (
+		red, 1,
+		image.Pt(10, 10),
+		image.Pt(70, 50),
+		image.Pt(20, 70))
 	
 	file, err := os.Create("TEST.png")
 	if err != nil { panic(err.Error()) }