Cached parameter added.

batch.go

@@ -26,7 +26,7 @@ var _ BasicTarget = (*Batch)(nil)
 //
 // Note, that if the container does not support TrianglesColor, color masking will not work.
 func NewBatch(container Triangles, pic Picture) *Batch {
-	b := &Batch{cont: Drawer{Triangles: container, Picture: pic}}
+	b := &Batch{cont: Drawer{Triangles: container, Picture: pic, Cached: true}}
 	b.SetMatrix(IM)
 	b.SetColorMask(Alpha(1))
 	return b

drawer.go

@@ -23,6 +23,7 @@ package pixel
 type Drawer struct {
 	Triangles Triangles
 	Picture   Picture
+	Cached    bool
 
 	targets    map[Target]*drawerTarget
 	allTargets []*drawerTarget
@@ -91,7 +92,10 @@ func (d *Drawer) Draw(t Target) {
 	pic := dt.pics[d.Picture]
 	if pic == nil {
 		pic = t.MakePicture(d.Picture)
-		dt.pics[d.Picture] = pic
+
+		if d.Cached {
+			dt.pics[d.Picture] = pic
+		}
 	}
 
 	pic.Draw(dt.tris)

sprite.go

@@ -27,7 +27,7 @@ func NewSprite(pic Picture, frame Rect) *Sprite {
 	tri := MakeTrianglesData(6)
 	s := &Sprite{
 		tri: tri,
-		d:   Drawer{Triangles: tri},
+		d:   Drawer{Triangles: tri, Cached: true},
 	}
 	s.matrix = IM
 	s.mask = Alpha(1)
@@ -44,6 +44,13 @@ func (s *Sprite) Set(pic Picture, frame Rect) {
 	}
 }
 
+// SetCached makes the sprite cache all the
+// incoming pictures if the argument is true, and
+// doesn't make it do that if the argument is false.
+func (s *Sprite) SetCached(cached bool) {
+	s.d.Cached = cached
+}
+
 // Picture returns the current Sprite's Picture.
 func (s *Sprite) Picture() Picture {
 	return s.d.Picture

text/text.go

@@ -136,6 +136,7 @@ func New(orig pixel.Vec, atlas *Atlas) *Text {
 
 	txt.transD.Picture = txt.atlas.pic
 	txt.transD.Triangles = &txt.trans
+	txt.transD.Cached = true
 
 	txt.Clear()