Only allow movement up to max

mwunsch · Oct 7, 2016 · 4904dd3 · 4904dd3
1 parent 552e819
commit 4904dd3
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Showing 2 changed files with 80 additions and 17 deletions.
diff --git a/src/Model.elm b/src/Model.elm
@@ -121,16 +121,35 @@ averageFighter pos =
     }
 
 
+
+-- TODO: move movement logic into attemptMove
+
+
 move : Model -> Position -> Model
 move model pos =
-    { model | position = pos }
+    let
+        distance =
+            Tabletop.distance model.position pos
+
+        newPos =
+            if distance > (toFloat model.remainingMove) then
+                maxAllowedMovement model pos
+            else
+                pos
+    in
+        { model | position = newPos }
 
 
 attemptMove : Model -> Position -> Result ( String, Model ) Model
 attemptMove model pos =
     Ok { model | position = pos }
 
 
+maxAllowedMovement : Model -> Position -> Position
+maxAllowedMovement model intent =
+    Tabletop.positionFromDirection model.position intent (toFloat model.remainingMove)
+
+
 type Injury
     = FleshWound
     | Down
@@ -162,13 +181,33 @@ movementView model pos =
 
         ( newX, newY ) =
             pos
+
+        distance =
+            Tabletop.distance model.position pos
+
+        ( maxX, maxY ) =
+            if distance > (toFloat model.remainingMove) then
+                maxAllowedMovement model pos
+            else
+                pos
     in
-        line
-            [ x1 (modelX |> toString)
-            , y1 (modelY |> toString)
-            , x2 (newX |> toString)
-            , y2 (newY |> toString)
-            , stroke "white"
-            , strokeWidth "0.25"
+        g []
+            [ line
+                [ x1 (modelX |> toString)
+                , y1 (modelY |> toString)
+                , x2 (maxX |> toString)
+                , y2 (maxY |> toString)
+                , stroke "white"
+                , strokeWidth "0.25"
+                ]
+                []
+            , line
+                [ x1 (maxX |> toString)
+                , y1 (maxY |> toString)
+                , x2 (newX |> toString)
+                , y2 (newY |> toString)
+                , stroke "grey"
+                , strokeWidth "0.25"
+                ]
+                []
             ]
-            []
diff --git a/src/Tabletop.elm b/src/Tabletop.elm
@@ -16,25 +16,25 @@ type alias Tabletop =
 
 
 type alias Position =
-    ( Int, Int )
+    ( Float, Float )
 
 
-posX : Position -> Int
+posX : Position -> Float
 posX ( x', _ ) =
     x'
 
 
-posY : Position -> Int
+posY : Position -> Float
 posY ( _, y' ) =
     y'
 
 
 positionFromMouseCoords : ( Int, Int ) -> Float -> Position
 positionFromMouseCoords ( x, y ) scale =
     let
-        transform : Int -> Int
+        transform : Int -> Float
         transform a =
-            round <| (toFloat a) / scale
+            (toFloat a) / scale
 
         x' =
             transform x
@@ -58,9 +58,33 @@ distance ( x1, y1 ) ( x2, y2 ) =
         x' =
             (x1 - x2) ^ 2
     in
-        (x' + y')
-            |> toFloat
-            |> sqrt
+        (x' + y') |> sqrt
+
+
+positionFromDirection : Position -> Position -> Float -> Position
+positionFromDirection start end len =
+    let
+        h =
+            distance start end
+
+        x' =
+            (posX end) - (posX start)
+
+        y' =
+            (posY end) - (posY start)
+
+        angle =
+            acos <| y' / h
+
+        co =
+            if x' > 0 then
+                1
+            else
+                -1
+    in
+        ( (posX start) + (sin angle * len) * co
+        , (posY start) + (cos angle * len)
+        )
 
 
 view : Tabletop -> List (Svg msg) -> Svg msg