Create another For iterator that leaves out the fake null rune

Apparently it was intended behavior. Closes #4

drawer.go

@@ -13,20 +13,20 @@ type Drawer struct { TypeSetter }
 // Draw draws the drawer's text onto the specified canvas at the given offset.
 func (drawer Drawer) Draw (
 	destination draw.Image,
-	color       color.Color,
+	col         color.Color,
 	offset      image.Point,
 ) (
 	updatedRegion image.Rectangle,
 ) {
-	source := image.NewUniform(color)
+	source := image.NewUniform(col)
 	
-	drawer.For (func (
+	drawer.ForRunes (func (
 		index    int,
 		char     rune,
 		position fixed.Point26_6,
 	) bool {
 		// leave empty space for space characters
-		if unicode.IsSpace(char){
+		if unicode.IsSpace(char) {
 			return true
 		}
 		
@@ -37,7 +37,7 @@ func (drawer Drawer) Draw (
 		mask, maskPoint, _, ok := drawer.face.Glyph(dot, char)
 		// tofu
 		if !ok {
-			drawer.drawTofu(char, destination, color, dot)
+			drawer.drawTofu(char, destination, col, dot)
 			return true
 		}
 

setter.go

@@ -259,8 +259,18 @@ type RuneIterator func (
 )
 
 // For calls the specified iterator for every rune in the typesetter. If the
-// iterator returns false, the loop will immediately stop.
+// iterator returns false, the loop will immediately stop. This method will
+// insert a fake null rune at the end.
 func (setter *TypeSetter) For (iterator RuneIterator) {
+	setter.forInternal(iterator, true)
+}
+
+// ForRunes is like For, but leaves out the fake null rune.
+func (setter *TypeSetter) ForRunes (iterator RuneIterator) {
+	setter.forInternal(iterator, false)
+}
+
+func (setter *TypeSetter) forInternal (iterator RuneIterator, fakeNull bool) {
 	setter.needAlignedLayout()
 
 	index := 0
@@ -271,7 +281,7 @@ func (setter *TypeSetter) For (iterator RuneIterator) {
 		for _, word := range line.Words {
 		for _, char := range word.Runes {
 			lastCharRightBound = word.X + char.X + char.Width
-			keepGoing := iterator (index, char.Rune, fixed.Point26_6 {
+			keepGoing := iterator(index, char.Rune, fixed.Point26_6 {
 				X: word.X + char.X,
 				Y: line.Y,
 			})
@@ -280,7 +290,7 @@ func (setter *TypeSetter) For (iterator RuneIterator) {
 		}}
 		
 		if line.BreakAfter {
-			keepGoing := iterator (index, '\n', fixed.Point26_6 {
+			keepGoing := iterator(index, '\n', fixed.Point26_6 {
 				X: lastCharRightBound,
 				Y: line.Y,
 			})
@@ -289,12 +299,14 @@ func (setter *TypeSetter) For (iterator RuneIterator) {
 		}
 	}
 	
-	keepGoing := iterator (index, '\000', fixed.Point26_6 {
-		X: lastCharRightBound,
-		Y: lastLineY,
-	})
-	if !keepGoing { return }
-	index ++
+	if fakeNull {
+		keepGoing := iterator (index, '\000', fixed.Point26_6 {
+			X: lastCharRightBound,
+			Y: lastLineY,
+		})
+		if !keepGoing { return }
+		index ++
+	}
 }
 
 // AtPosition returns the index of the rune at the specified position.