Render Z levels slightly more accurately

cmd/view-map/main.go

@@ -222,10 +222,11 @@ func (s *state) renderCell(x, y, z int, target pixel.Target) {
 
 	// Taking the Z index away *seems* to draw the object in the correct place.
 	// FIXME: There are some artifacts, investigate more
-	fX := float64(x - z)
-	fY := float64(y - z)
+	fX := float64(x)
+	fY := float64(y)
 
 	iso := s.cellToPix(pixel.V(fX, fY))
+	iso = iso.Add(pixel.Vec{0.0, -float64(z * 48.0)})
 
 	for _, sprite := range sprites {
 		sprite.Spr.Draw(target, pixel.IM.Moved(iso))