fix: unnatural movement around obstacles

- predict next location based on moving direction
- add UP and DOWN to Direction as aliases of TOP and BOTTOM, for moving directions instead of location

1 files changed, 9 insertions, 3 deletions

diff --git a/objects/Obstacle.lua b/objects/Obstacle.lua
index fb66611..dc6a944 100644
--- a/objects/Obstacle.lua
+++ b/objects/Obstacle.lua
@@ -24,11 +24,17 @@ function Obstacle:getBorders()
     return { left, right, top, bottom }
 end
 
-function Obstacle:isMet(body, currentX, currentY, dv)
+function Obstacle:isMet(body, currentX, currentY, dv, dir)
     -- x,y should be the predicted next location of this body
     -- dv = speed * dt * direction
-    local x = currentX + dv
-    local y = currentY + dv
+    local x, y
+    if dir == Direction.LEFT or dir == Direction.RIGHT then
+        x = currentX + dv
+        y = currentY
+    elseif dir == Direction.UP or dir == Direction.DOWN then
+        x = currentX
+        y = currentY + dv
+    end
 
     return self.body:collide(body, self.x, self.y, x, y)
 end