Animating a nice backbuffer. Thank you Casey Muratori of Handmade Hero fame (https://www.youtube.com/watch?v=hNKU8Jiza2g)

ui/run.go

@@ -1,7 +1,6 @@
 package ui
 
 import (
-	"fmt"
 	"log"
 	"runtime"
 
@@ -9,8 +8,10 @@ import (
 	"github.com/veandco/go-sdl2/ttf"
 )
 
-var renderer *sdl.Renderer
-var font *ttf.Font
+const (
+	windowWidth  = 800
+	windowHeight = 600
+)
 
 func init() {
 	runtime.LockOSThread()
@@ -31,45 +32,27 @@ func Run(romPath string) {
 		"GB Player",
 		sdl.WINDOWPOS_UNDEFINED,
 		sdl.WINDOWPOS_UNDEFINED,
-		800, 600,
+		windowWidth, windowHeight,
 		sdl.WINDOW_SHOWN)
 	if err != nil {
 		panic(err)
 	}
 	defer window.Destroy()
 
-	renderer, err = sdl.CreateRenderer(window, -1, 0)
+	renderer, err := sdl.CreateRenderer(window, -1, 0)
 	if err != nil {
 		panic(err)
 	}
 	defer renderer.Destroy()
 	renderer.RenderSetVSync(true)
 
-	font, err = ttf.OpenFont("SourceCodePro.ttf", 18)
+	font, err := ttf.OpenFont("SourceCodePro.ttf", 18)
 	if err != nil {
 		log.Fatal(err)
 	}
 	defer font.Close()
 	font.SetStyle(ttf.STYLE_BOLD)
 
-	controller := NewController(renderer)
+	controller := NewController(window, renderer, font)
 	controller.Start(romPath)
 }
-
-func drawDebugWindow(fps float64) {
-	// FPS
-	textSurface, err := font.RenderUTF8Blended(fmt.Sprintf("FPS: %.2f", fps), sdl.Color{R: 0, G: 0, B: 0, A: 255})
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer textSurface.Free()
-
-	textTexture, err := renderer.CreateTextureFromSurface(textSurface)
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer textTexture.Destroy()
-
-	textRect := sdl.Rect{X: 0, Y: 0, W: textSurface.W, H: textSurface.H}
-	renderer.Copy(textTexture, nil, &textRect)
-}