add functionality to flip drawing horizontally

fcore/grid.sml

@@ -32,4 +32,14 @@ struct
   fun makeEmpty maxSide =
     Vector.tabulate (maxSide, fn _ =>
       Vector.tabulate (maxSide, fn _ => emptyPixel))
+
+  fun flipHorizontally (xAxis: t) =
+    Vector.mapi
+      (fn (xIdx, yAxis) =>
+         let
+           val flippedXIdx = Vector.length xAxis - 1 - xIdx
+           val flippedYAxis = Vector.sub (xAxis, flippedXIdx)
+         in
+           Vector.mapi (fn (yIdx, _) => Vector.sub (flippedYAxis, yIdx)) yAxis
+         end) xAxis
 end

fcore/layer-tree.sml

@@ -107,4 +107,6 @@ struct
     in
       insert (key, grid, tree)
     end
+
+  fun flipHorizontally tree = map (Grid.flipHorizontally, tree)
 end

fcore/normal-mode.sml

@@ -369,6 +369,15 @@ struct
     in (model, [])
     end
 
+  fun flipHorizontally (model: app_type) =
+    let
+      val {layerTree, arrowX, arrowY, ...} = model
+      val layerTree = LayerTree.flipHorizontally layerTree
+      val model = AppWith.layerTree (model, layerTree, arrowX, arrowY)
+    in
+      getDrawMessage (model, [])
+    end
+
   fun update (model: app_type, inputMsg) =
     case inputMsg of
       MOUSE_MOVE {x = mouseX, y = mouseY} =>
@@ -388,6 +397,7 @@ struct
     | KEY_W => updateCanvasWidth model
     | KEY_H => updateCanvasHeight model
     | KEY_M => enterMoveMode model
+    | KEY_F => flipHorizontally model
     | RESIZE_WINDOW {width, height} => resizeWindow (model, width, height)
     | UNDO_ACTION => undoAction model
     | REDO_ACTION => redoAction model

ffi/glfw-input.c

@@ -24,6 +24,7 @@ int KEY_W = GLFW_KEY_W;
 int KEY_H = GLFW_KEY_H;
 int KEY_C = GLFW_KEY_C;
 int KEY_M = GLFW_KEY_M;
+int KEY_F = GLFW_KEY_F;
 
 int KEY_ENTER = GLFW_KEY_ENTER;
 int KEY_SPACE = GLFW_KEY_SPACE;

ffi/glfw-input.sml

@@ -41,6 +41,8 @@ struct
     _symbol "KEY_C" public : ( unit -> int ) * ( int -> unit );
   val (KEY_M, _) =
     _symbol "KEY_M" public : ( unit -> int ) * ( int -> unit );
+  val (KEY_F, _) =
+    _symbol "KEY_F" public : ( unit -> int ) * ( int -> unit );
 
   val (KEY_T, _) =
     _symbol "KEY_T" public : ( unit -> int ) * ( int -> unit );

green.dsc

@@ -1,3 +1,3 @@
-24 3 {
-[  {0 1 0 1 0 0 0 1 } {1 0 22 0 0 0 0 1 } {1 1 22 1 239 239 239 1 } {1 2 22 2 0 0 0 1 } {23 1 23 1 0 0 0 1 } ]
+50 50 { 
+  [  { 1 48 1 50 0 0 0 1 }  { 1 49 18 50 0 0 0 1 }  { 2 47 2 47 0 0 0 1 }  { 3 46 3 46 0 0 0 1 }  { 4 45 5 45 0 0 0 1 }  { 6 44 7 44 0 0 0 1 }  { 8 43 9 43 0 0 0 1 }  { 10 38 10 42 0 0 0 1 }  { 10 42 11 42 0 0 0 1 }  { 11 35 11 37 0 0 0 1 }  { 12 33 12 34 0 0 0 1 }  { 13 31 13 32 0 0 0 1 }  { 14 30 14 30 0 0 0 1 }  { 15 29 15 29 0 0 0 1 }  { 16 28 16 28 0 0 0 1 }  { 17 25 17 27 0 0 0 1 }  { 17 29 17 30 0 0 0 1 }  { 17 42 18 42 0 0 0 1 }  { 18 24 18 24 0 0 0 1 }  { 18 31 18 32 0 0 0 1 }  { 18 42 18 50 0 0 0 1 }  { 19 23 19 23 0 0 0 1 }  { 19 33 19 33 0 0 0 1 }  { 19 39 19 41 0 0 0 1 }  { 20 22 20 22 0 0 0 1 }  { 20 30 20 32 0 0 0 1 }  { 20 34 20 38 0 0 0 1 }  { 21 27 21 29 0 0 0 1 }  { 22 25 22 26 0 0 0 1 }  { 23 24 23 24 0 0 0 1 }  ]
 }

imperative-shell/input-callbacks.sml

@@ -180,6 +180,10 @@ struct
       key = Input.KEY_M () andalso action = Input.PRESS () andalso mods = 0
     then
       Mailbox.send (mailbox, KEY_M)
+    else if
+      key = Input.KEY_F () andalso action = Input.PRESS () andalso mods = 0
+    then
+      Mailbox.send (mailbox, KEY_F)
     else
       ()
 

message-types/input-msg.sml

@@ -17,6 +17,7 @@ struct
   | KEY_M
   | KEY_C
   | KEY_L
+  | KEY_F
   | KEY_BACKSPACE
   | KEY_CTRL_S
   | KEY_CTRL_L