make UI smoother

fix: make CtrlW (center circuit in window) work consistently
feat: add button to memory source change menu

src/Renderer/DrawBlock/Sheet.fs

@@ -471,12 +471,14 @@ let getWindowParasToFitBox model (box: BoundingBox)  =
     getScreenEdgeCoords model
     |> Option.map (fun edge -> 
         let lh,rh,top,bottom = edge.Left,edge.Right,edge.Top,edge.Bottom
+        printfn $"------------------\nbox LRTB=({edge.Left},{edge.Right},{edge.Top},{edge.Bottom})" //>
         let wantedMag = min ((rh - lh)/box.W) ((bottom-top)/box.H)
         let magToUse = min wantedMag Constants.maxMagnification
         let xMiddle = (box.TopLeft.X + box.W/2.)*magToUse
         let xScroll = xMiddle - (rh-lh)/2.
         let yMiddle = (box.TopLeft.Y + (box.H)/2.)*magToUse
         let yScroll = yMiddle - (bottom-top)/2.
+        printfn $"mid XY=({xMiddle},{yMiddle}) scroll XY={xScroll},{yScroll}\n----------------" //>
         {|Scroll={X=xScroll; Y=yScroll}; MagToUse=magToUse|})
 
 let addBoxMargin (fractionalMargin:float) (absoluteMargin:float) (box: BoundingBox) =

src/Renderer/DrawBlock/SheetUpdate.fs

@@ -241,7 +241,7 @@ let update (msg : Msg) (issieModel : ModelType.Model): ModelType.Model*Cmd<Model
                 sheetCmd CheckAutomaticScrolling // Also check if there is automatic scrolling to continue
             else
                 Cmd.none
-        // keep last 4 updates yo filte corresponding OnScroll events
+        // keep last 4 updates to filter corresponding OnScroll events
         recentProgrammaticScrollPos <- scrollPos :: List.truncate 4 recentProgrammaticScrollPos
         scrollSequence <- scrollSequence + 1 // increment sequence counter
         viewIsAfterUpdateScroll <- true

src/Renderer/DrawBlock/SheetUpdateHelpers.fs

@@ -20,14 +20,16 @@ let fitCircuitToScreenUpdate (model: Model) =
     let model', parasOpt = fitCircuitToWindowParas model
     match parasOpt with
     | Some paras ->
-        //printf "CtrlW Calculated Scroll = %A" paras.Scroll
+        printf "CtrlW Calculated Scroll = %A" paras.Scroll //>
         model', 
         Cmd.batch 
             [
                 sheetCmd (SheetT.Msg.UpdateScrollPos paras.Scroll)
                 sheetCmd SheetT.Msg.UpdateBoundingBoxes
                 if abs (model.Zoom - model'.Zoom) > 0.001 then
-                    sheetCmd (SheetT.Msg.KeyPress CtrlW)
+                    printfn "Sheet has chnaged: recursively called CtrlW" //>
+                    ModelType.Msg.RunAfterRender (false, (fun dispatch model -> (dispatch <| ModelType.Msg.Sheet (SheetT.Msg.KeyPress CtrlW)); model))
+                    |> Cmd.ofMsg
             ]
     | None -> model, Cmd.none
 

src/Renderer/Model/ModelType.fs

@@ -508,7 +508,7 @@ type Msg =
     | SaveModel
     | CheckMemory
     | ChangeWaveSimMultiplier of int
-    | RunAfterRender of ((Msg -> unit) * ((Msg -> unit) -> Model -> Model))
+    | RunAfterRender of (bool * ((Msg -> unit) -> Model -> Model))
 
 
 //================================//

src/Renderer/UI/MenuHelpers.fs

@@ -259,6 +259,18 @@ let makeSourceMenu
             br []; br []
             Menu.menu []
                 [ Menu.list [] menu ]
+            Level.level [ Level.Level.Props [ Style [ Width "100%"; PaddingTop "20px"] ] ] [
+                Level.left [] []
+                Level.right [] [
+                    Level.item [] [
+                        Button.button [
+                            Button.Color IsSuccess
+                            Button.OnClick (fun _ -> 
+                                dispatch ClosePopup)
+                        ] [ str "Change Source" ]
+                    ]
+                ]
+            ]
 
         ]
 
@@ -664,6 +676,8 @@ let setupProjectFromComponents (finishUI:bool) (sheetName: string) (ldComps: Loa
     }
     |> SetProject // this message actually changes the project in model
     |> dispatch
+    printfn "Centering schematic" //>
+    //dispatch <| Sheet (SheetT.KeyPress  SheetT.KeyboardMsg.CtrlW) //>
     dispatch SynchroniseCanvas
 
 

src/Renderer/UI/Update.fs

@@ -68,8 +68,8 @@ let update (msg : Msg) oldModel =
     //-------------------------------------------------------------------------------//
 
     match testMsg with
-    | RunAfterRender( dispatch, fn) ->
-        {model with RunAfterRenderWithSpinner = Some {FnToRun=fn; ButtonSpinnerOn = true}}, Cmd.none
+    | RunAfterRender( withSpinner, fn) ->
+        {model with RunAfterRenderWithSpinner = Some {FnToRun=fn; ButtonSpinnerOn = withSpinner}}, Cmd.none
 
     | ChangeWaveSimMultiplier key ->
         let table = Constants.multipliers

src/Renderer/UI/WaveSim/WaveSimTop.fs

@@ -286,7 +286,7 @@ let refreshButtonAction canvasState model dispatch = fun _ ->
                 dispatch <| UpdateWSModel (fun wsModel -> {wsModel with  DefaultCursor = Default})
             else
                 dispatch <| SetWSModelAndSheet ({ wsModel with State = NonSequential}, wsSheet)
-    dispatch <| RunAfterRender(dispatch, fun dispatch model -> startWaveSimulation dispatch model; model)
+    dispatch <| RunAfterRender(true, fun dispatch model -> startWaveSimulation dispatch model; model)