From 7be3a4383c91a9ea4841fa4588556ebca7442fa0 Mon Sep 17 00:00:00 2001
From: Thomas Friedel <tomee6@gmail.com>
Date: Wed, 4 Apr 2018 15:53:26 +0200
Subject: [PATCH] paths with sub-paths fixed

---
 paths.go         | 35 ++++++++++++++++++++++++++---------
 triangulation.go | 16 ++++++++--------
 2 files changed, 34 insertions(+), 17 deletions(-)

diff --git a/paths.go b/paths.go
index c956f99..1e48ec2 100644
--- a/paths.go
+++ b/paths.go
@@ -231,9 +231,16 @@ func (cv *Canvas) ClosePath() {
 	if isSamePoint(cv.linePath[len(cv.linePath)-1].tf, cv.linePath[0].tf, 0.1) {
 		return
 	}
-	cv.LineTo(cv.linePath[0].pos[0], cv.linePath[0].pos[1])
-	cv.linePath[len(cv.linePath)-1].next = cv.linePath[0].tf
-	cv.polyPath[len(cv.polyPath)-1].next = cv.polyPath[0].tf
+	closeIdx := 0
+	for i := len(cv.linePath) - 1; i >= 0; i-- {
+		if cv.linePath[i].move {
+			closeIdx = i
+			break
+		}
+	}
+	cv.LineTo(cv.linePath[closeIdx].pos[0], cv.linePath[closeIdx].pos[1])
+	cv.linePath[len(cv.linePath)-1].next = cv.linePath[closeIdx].tf
+	cv.polyPath[len(cv.polyPath)-1].next = cv.polyPath[closeIdx].tf
 }
 
 func (cv *Canvas) Stroke() {
@@ -424,14 +431,24 @@ func lineIntersection(a0, a1, b0, b1 vec) (vec, float64, float64) {
 }
 
 func (cv *Canvas) Fill() {
-	lastMove := 0
-	for i, p := range cv.polyPath {
-		if p.move {
-			lastMove = i
-		}
+	if len(cv.polyPath) < 3 {
+		return
 	}
+	cv.activate()
+	start := 0
+	for i, p := range cv.polyPath {
+		if !p.move {
+			continue
+		}
+		if i >= start+3 {
+			cv.fillPoly(start, i)
+		}
+		start = i
+	}
+}
 
-	path := cv.polyPath[lastMove:]
+func (cv *Canvas) fillPoly(from, to int) {
+	path := cv.polyPath[from:to]
 	if len(path) < 3 {
 		return
 	}
diff --git a/triangulation.go b/triangulation.go
index a1fc2be..ad3c20f 100644
--- a/triangulation.go
+++ b/triangulation.go
@@ -113,17 +113,17 @@ func (cv *Canvas) cutIntersections(path []pathPoint) []pathPoint {
 	var cutBuf [50]cut
 	cuts := cutBuf[:0]
 
-	for i := 0; i < len(cv.polyPath); i++ {
-		ip := (i + len(cv.polyPath) - 1) % len(cv.polyPath)
-		a0 := cv.polyPath[ip].pos
-		a1 := cv.polyPath[i].pos
-		for j := i + 1; j < len(cv.polyPath); j++ {
-			jp := (j + len(cv.polyPath) - 1) % len(cv.polyPath)
+	for i := 0; i < len(path); i++ {
+		ip := (i + len(path) - 1) % len(path)
+		a0 := path[ip].pos
+		a1 := path[i].pos
+		for j := i + 1; j < len(path); j++ {
+			jp := (j + len(path) - 1) % len(path)
 			if ip == j || jp == i {
 				continue
 			}
-			b0 := cv.polyPath[jp].pos
-			b1 := cv.polyPath[j].pos
+			b0 := path[jp].pos
+			b1 := path[j].pos
 			p, r1, r2 := lineIntersection(a0, a1, b0, b1)
 			if r1 <= 0 || r1 >= 1 || r2 <= 0 || r2 >= 1 {
 				continue