calculate inventory matrix based on current inv items - fix

pkg/data/items.go

@@ -61,10 +61,9 @@ func (i Inventory) Matrix() [4][10]bool {
 	invMatrix := [4][10]bool{} // false = empty, true = occupied
 	for _, itm := range i.ByLocation(item.LocationInventory) {
 		for k := range itm.Desc().InventoryWidth {
-			invMatrix[itm.Position.Y][itm.Position.X+k] = true
-		}
-		for k := range itm.Desc().InventoryHeight {
-			invMatrix[itm.Position.Y+k][itm.Position.X] = true
+			for j := range itm.Desc().InventoryHeight {
+				invMatrix[itm.Position.Y+j][itm.Position.X+k] = true
+			}
 		}
 	}