Update the UI on game start

* update UI even when paused
* send frame events earlier

* closes #2081

app/game/Swarm/App.hs

@@ -77,8 +77,8 @@ appMain opts = do
       chan <- newBChan 5
       _ <- forkIO $
         forever $ do
-          threadDelay 33_333 -- cap maximum framerate at 30 FPS
           writeBChan chan Frame
+          threadDelay 33_333 -- cap maximum framerate at 30 FPS
 
       _ <- forkIO $ do
         upRel <- getNewerReleaseVersion (repoGitInfo opts)

src/swarm-tui/Swarm/TUI/Controller.hs

@@ -87,6 +87,7 @@ import Swarm.Language.Value (Value (VKey), envTypes)
 import Swarm.Log
 import Swarm.TUI.Controller.EventHandlers
 import Swarm.TUI.Controller.SaveScenario (saveScenarioInfoOnQuit)
+import Swarm.TUI.Controller.UpdateUI (updateAndRedrawUI)
 import Swarm.TUI.Controller.Util
 import Swarm.TUI.Editor.Controller qualified as EC
 import Swarm.TUI.Editor.Model
@@ -287,13 +288,12 @@ handleMainEvent forceRedraw ev = do
   let keyHandler = s ^. keyEventHandling . keyDispatchers . to mainGameDispatcher
   case ev of
     AppEvent ae -> case ae of
-      Frame
-        -- If the game is paused, don't run any game ticks, but do redraw the screen
-        -- if a redraw is forced.
-        | s ^. gameState . temporal . paused -> unless forceRedraw continueWithoutRedraw
-        | otherwise -> runFrameUI forceRedraw
+      -- If the game is paused, don't run any game ticks, but do redraw if needed.
+      Frame ->  if s ^. gameState . temporal . paused
+        then updateAndRedrawUI forceRedraw
+        else runFrameUI forceRedraw
       Web (RunWebCode c) -> runBaseWebCode c
-      _ -> continueWithoutRedraw
+      UpstreamVersion _ -> error "version event should be handled by top-level handler"
     VtyEvent (V.EvResize _ _) -> invalidateCache
     EscapeKey | Just m <- s ^. uiState . uiGameplay . uiModal -> closeModal m
     -- Pass to key handler (allows users to configure bindings)

src/swarm-tui/Swarm/TUI/Controller/EventHandlers/Frame.hs

@@ -38,10 +38,7 @@ ticksPerFrameCap = 30
 --   this may involve stepping the game any number of ticks (including
 --   zero).
 runFrameUI :: Bool -> EventM Name AppState ()
-runFrameUI forceRedraw = do
-  runFrame
-  redraw <- updateUI
-  unless (forceRedraw || redraw) continueWithoutRedraw
+runFrameUI forceRedraw = runFrame >> updateAndRedrawUI forceRedraw
 
 -- | Run the game for a single frame, without updating the UI.
 runFrame :: EventM Name AppState ()

src/swarm-tui/Swarm/TUI/Controller/UpdateUI.hs

@@ -6,6 +6,7 @@
 -- The main TUI update logic that is called from other controller parts.
 module Swarm.TUI.Controller.UpdateUI (
   updateUI,
+  updateAndRedrawUI,
 ) where
 
 import Brick hiding (Direction, Location)
@@ -43,6 +44,14 @@ import Swarm.TUI.View.Objective qualified as GR
 import Witch (into)
 import Prelude hiding (Applicative (..))
 
+-- | Update the UI and redraw if needed.
+--
+-- This function is used after running the game for some number of ticks.
+updateAndRedrawUI :: Bool -> EventM Name AppState ()
+updateAndRedrawUI forceRedraw = do
+  redraw <- updateUI
+  unless (forceRedraw || redraw) continueWithoutRedraw
+
 -- | Update the UI.  This function is used after running the
 --   game for some number of ticks.
 updateUI :: EventM Name AppState Bool