geom.go
func (g *GeoM) Translate(tx, ty float64) {
	g.tx += float32(tx)
	g.ty += float32(ty)
}
func (g *GeoM) Translate(tx, ty float64) {
	g.tx += float32(tx)
	g.ty += float32(ty)
}
// Translate translates the matrix by (tx, ty).