Moved game loop examples from README into the examples repository

Signed-off-by: Lilis Iskandar <[email protected]>

README.md

@@ -199,194 +199,7 @@ func main() {
 }
 ```
 
-There are two ways a game might be running: one that updates on user input and one that updates regardless of user input. The following example updates on user input:
-```go
-package main
-
-import "github.com/veandco/go-sdl2/sdl"
-
-const (
-	TITLE  = "README"
-	WIDTH  = 800
-	HEIGHT = 600
-)
-
-var (
-	playerX, playerY = int32(WIDTH / 2), int32(HEIGHT / 2)
-)
-
-func main() {
-	if err := sdl.Init(sdl.INIT_EVERYTHING); err != nil {
-		panic(err)
-	}
-	defer sdl.Quit()
-
-	window, err := sdl.CreateWindow(TITLE, sdl.WINDOWPOS_UNDEFINED, sdl.WINDOWPOS_UNDEFINED, WIDTH, HEIGHT, sdl.WINDOW_SHOWN)
-	if err != nil {
-		panic(err)
-	}
-	defer window.Destroy()
-
-	surface, err := window.GetSurface()
-	if err != nil {
-		panic(err)
-	}
-
-	// Draw initial frame
-	draw(window, surface)
-
-	for event := sdl.WaitEvent(); event != nil; event = sdl.WaitEvent() {
-		switch t := event.(type) {
-		case sdl.QuitEvent: // NOTE: Please use `*sdl.QuitEvent` for `v0.4.x` (current version).
-			println("Quitting..")
-			return
-		case sdl.KeyboardEvent:
-			if t.State == sdl.RELEASED {
-				if t.Keysym.Sym == sdl.K_LEFT {
-					playerX -= 4
-				} else if t.Keysym.Sym == sdl.K_RIGHT {
-					playerX += 4
-				}
-				if t.Keysym.Sym == sdl.K_UP {
-					playerY -= 4
-				} else if t.Keysym.Sym == sdl.K_DOWN {
-					playerY += 4
-				}
-				if playerX < 0 {
-					playerX = WIDTH
-				} else if playerX > WIDTH {
-					playerX = 0
-				}
-				if playerY < 0 {
-					playerY = HEIGHT
-				} else if playerY > HEIGHT {
-					playerY = 0
-				}
-				draw(window, surface)
-			}
-			break
-		}
-	}
-}
-
-func draw(window *sdl.Window, surface *sdl.Surface) {
-	// Clear surface
-	surface.FillRect(nil, 0)
-
-	// Draw on the surface
-	rect := sdl.Rect{playerX, playerY, 4, 4}
-	colour := sdl.Color{R: 255, G: 0, B: 255, A: 255} // purple
-	pixel := sdl.MapRGBA(surface.Format, colour.R, colour.G, colour.B, colour.A)
-	surface.FillRect(&rect, pixel)
-
-	window.UpdateSurface()
-}
-```
-
-And this one updates many times per second regardless of user input according to the desired framerate:
-```go
-package main
-
-import "github.com/veandco/go-sdl2/sdl"
-
-const (
-	TITLE     = "README"
-	WIDTH     = 800
-	HEIGHT    = 600
-	FRAMERATE = 60
-)
-
-var (
-	playerX, playerY   = int32(WIDTH / 2), int32(HEIGHT / 2)
-	playerVX, playerVY = int32(0), int32(0)
-	running            = true
-)
-
-func main() {
-	if err := sdl.Init(sdl.INIT_EVERYTHING); err != nil {
-		panic(err)
-	}
-	defer sdl.Quit()
-
-	window, err := sdl.CreateWindow(TITLE, sdl.WINDOWPOS_UNDEFINED, sdl.WINDOWPOS_UNDEFINED, WIDTH, HEIGHT, sdl.WINDOW_SHOWN)
-	if err != nil {
-		panic(err)
-	}
-	defer window.Destroy()
-
-	surface, err := window.GetSurface()
-	if err != nil {
-		panic(err)
-	}
-
-	for running {
-		for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
-			handleEvent(event)
-		}
-
-		loopTime := loop(surface)
-		window.UpdateSurface()
-
-		delay := (1000 / FRAMERATE) - loopTime
-		sdl.Delay(delay)
-	}
-}
-
-func handleEvent(event sdl.Event) {
-	switch t := event.(type) {
-	case sdl.QuitEvent: // NOTE: Please use `*sdl.QuitEvent` for `v0.4.x` (current version).
-		println("Quitting..")
-		running = false
-		break
-	case sdl.KeyboardEvent:
-		if t.State == sdl.RELEASED {
-			if t.Keysym.Sym == sdl.K_LEFT {
-				playerVX -= 1
-			} else if t.Keysym.Sym == sdl.K_RIGHT {
-				playerVX += 1
-			}
-			if t.Keysym.Sym == sdl.K_UP {
-				playerVY -= 1
-			} else if t.Keysym.Sym == sdl.K_DOWN {
-				playerVY += 1
-			}
-		}
-		break
-	}
-}
-
-func loop(surface *sdl.Surface) (loopTime uint32) {
-	// Get time at the start of the function
-	startTime := sdl.GetTicks()
-
-	// Update player position
-	playerX += playerVX
-	playerY += playerVY
-	if playerX < 0 {
-		playerX = WIDTH
-	} else if playerX > WIDTH {
-		playerX = 0
-	}
-	if playerY < 0 {
-		playerY = HEIGHT
-	} else if playerY > HEIGHT {
-		playerY = 0
-	}
-
-	// Clear surface
-	surface.FillRect(nil, 0)
-
-	// Draw on the surface
-	rect := sdl.Rect{playerX, playerY, 4, 4}
-	colour := sdl.Color{R: 255, G: 0, B: 255, A: 255} // purple
-	pixel := sdl.MapRGBA(surface.Format, colour.R, colour.G, colour.B, colour.A)
-	surface.FillRect(&rect, pixel)
-
-	// Calculate time passed since start of the function
-	endTime := sdl.GetTicks()
-	return endTime - startTime
-}
-```
+There are two ways a game might be running: one that updates on user input using `sdl.WaitEvent()` and one that updates regardless of user input using `sdl.PollEvent()`. You can check the examples of those two loops [here](https://github.com/veandco/go-sdl2-examples/tree/master/examples/gameloop).
 
 For more runnable examples, see https://github.com/veandco/go-sdl2-examples. You can run any of the `.go` files with `go run`.