Use screen scaling

internal/ui/window.go

@@ -13,8 +13,7 @@ import (
 )
 
 var (
-	winX = flag.Int("win-x", 1280, "width of the view-map window")
-	winY = flag.Int("win-y", 1024, "height of the view-map window")
+	screenScale = flag.Float64("screen-scale", 1.0, "Scale the window by this factor")
 
 	cpuprofile = flag.String("cpuprofile", "", "write cpu profile to `file`")
 )
@@ -29,6 +28,7 @@ type Window struct {
 	drawFn   func(*ebiten.Image) error
 
 	debug bool
+	firstRun bool
 }
 
 // 0,0 is the *top left* of the window
@@ -41,6 +41,7 @@ func NewWindow(title string) (*Window, error) {
 		Title:         title,
 		KeyUpHandlers: make(map[ebiten.Key]func()),
 		debug:         true,
+		firstRun:      true,
 	}, nil
 }
 
@@ -54,6 +55,11 @@ func (w *Window) OnMouseWheel(f func(x, y float64)) {
 }
 
 func (w *Window) run(screen *ebiten.Image) error {
+	if w.firstRun {
+		ebiten.SetScreenScale(*screenScale)
+		w.firstRun = false
+	}
+
 	if err := w.updateFn(); err != nil {
 		return err
 	}
@@ -108,5 +114,5 @@ func (w *Window) Run(updateFn func() error, drawFn func(*ebiten.Image) error) er
         defer pprof.StopCPUProfile()
     }
 
-	return ebiten.Run(w.run, *winX, *winY, 1, w.Title)
+	return ebiten.Run(w.run, 640, 480, 1, w.Title) // Native game resolution: 640x480
 }