From 7fe09053e3e0a789cdbef8962a718c7b6503e9c3 Mon Sep 17 00:00:00 2001
From: Daniel Barlow <dan@telent.net>
Date: Sat, 16 Nov 2024 00:00:16 +0000
Subject: [PATCH] remove MapZoom{In,Out} messages

they can both be replaced with MapScale
---
 frontend/src/Main.elm | 20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/frontend/src/Main.elm b/frontend/src/Main.elm
index a991068..f999e5e 100644
--- a/frontend/src/Main.elm
+++ b/frontend/src/Main.elm
@@ -177,9 +177,7 @@ fetchTrack start duration = Http.get
 -- UPDATE
 
 type Msg
-  = MapZoomIn
-  | MapZoomOut
-  | MapScale Float
+  = MapScale Int
   | PointerDown (Int, Int)
   | PointerMove (Int, Int)
   | PointerUp (Int, Int)
@@ -195,15 +193,8 @@ update msg model = (newModel msg model, Cmd.none)
 
 newModel msg model =
     case msg of
-        MapZoomIn ->
-            { model | zoom = incZoom model.zoom zoomStep }
-
-        MapZoomOut ->
-            { model | zoom = incZoom model.zoom -zoomStep }
-
         MapScale y ->
-            let dir = floor(abs(y)/y)
-            in { model | zoom = incZoom model.zoom dir }
+            { model | zoom = incZoom model.zoom y }
 
         PointerDown (x,y) ->
             { model | drag = Dragging (x,y) (x,y) }
@@ -420,7 +411,8 @@ withSwallowing m =
 
 -- FIXME should do something useful with deltaMode as well as deltaY
 mapWheelDecoder =
-    D.map (withSwallowing << MapScale) (D.field "deltaY" D.float)
+    let sgn x = floor((abs x)/x)
+    in D.map (withSwallowing << MapScale << sgn) (D.field "deltaY" D.float)
 
 timeWheelDecoder =
     D.map (withSwallowing << TimeScale) (D.field "deltaY" D.float)
@@ -443,8 +435,8 @@ viewDiv model =
                     [canvasV]
               , text ("Zoom level " ++ (String.fromInt (toZoom model.zoom)))
               , span []
-                  [ button [ onClick MapZoomOut ] [ text "-" ]
-                  , button [ onClick MapZoomIn ] [ text "+" ]
+                  [ button [ onClick (MapScale -zoomStep) ] [ text "-" ]
+                  , button [ onClick (MapScale zoomStep) ] [ text "+" ]
                   ]
               ]
         , div [ style "display" "flex"