Splitting up functions, introducing the game director

game.go

@@ -1,63 +1,14 @@
 package main
 
 import (
-	"fmt"
 	"log"
-	"strconv"
+	"time"
 
 	"github.com/gdamore/tcell/v2"
 )
 
-func updateScore(screen tcell.Screen, style tcell.Style, score int) {
+func initilize() (tcell.Screen, tcell.Style, error) {
-	var x, y int
+	style := tcell.StyleDefault.Background(tcell.ColorReset).Foreground(tcell.ColorReset)
-	_, y = screen.Size()
-	x = 5
-	for _, r := range []rune("[ Score: " + strconv.FormatInt(int64(score), 10) + " ]") {
-		screen.SetContent(x, y-1, r, nil, style)
-		x++
-	}
-}
-
-func drawBox(s tcell.Screen, x1, y1, x2, y2 int, style tcell.Style) {
-	if y2 < y1 {
-		y1, y2 = y2, y1
-	}
-	if x2 < x1 {
-		x1, x2 = x2, x1
-	}
-
-	// Fill background
-	for row := y1; row <= y2; row++ {
-		for col := x1; col <= x2; col++ {
-			s.SetContent(col, row, ' ', nil, style)
-		}
-	}
-
-	// Draw borders
-	for col := x1; col <= x2; col++ {
-		s.SetContent(col, y1, '═', nil, style)
-		s.SetContent(col, y2, '═', nil, style)
-	}
-	for row := y1 + 1; row < y2; row++ {
-		s.SetContent(x1, row, '║', nil, style)
-		s.SetContent(x2, row, '║', nil, style)
-	}
-
-	// Only draw corners if necessary
-	if y1 != y2 && x1 != x2 {
-		s.SetContent(x1, y1, '╔', nil, style)
-		s.SetContent(x2, y1, '╗', nil, style)
-		s.SetContent(x1, y2, '╚', nil, style)
-		s.SetContent(x2, y2, '╝', nil, style)
-	}
-
-	//drawText(s, x1+1, y1+1, x2-1, y2-1, style, text)
-	updateScore(s, style, 10)
-}
-
-func main() {
-
-	defaultStyle := tcell.StyleDefault.Background(tcell.ColorReset).Foreground(tcell.ColorReset)
 
 	var err error
 
@@ -69,33 +20,48 @@ func main() {
 	if err != nil {
 		log.Fatalln("Error initializing screen: ", err)
 	}
+	return screen, style, err
+}
+
+func quit(screen tcell.Screen) {
+	maybePanic := recover()
+	screen.Fini()
+	if maybePanic != nil {
+		panic(maybePanic)
+	}
+}
+
+func game_director(screen tcell.Screen, style tcell.Style) {
+
+	//var score int
+	//var scoreCounter int = 1
+	//var field [80][24]int
+	// fill up the field:
+	// 0: empty
+	// 1: snake
+	// 2: apple
+	// 3: border
 
 	x, y := screen.Size()
+	drawBox(screen, 0, 0, x-1, y-1, style)
 
-	screen.Clear()
+	var snakex int = 3
-
+	var snakey int = 12
-	drawBox(screen, 0, 0, x-1, y-1, defaultStyle)
-
-	quit := func() {
-		// You have to catch panics in a defer, clean up, and
-		// re-raise them - otherwise your application can
-		// die without leaving any diagnostic trace.
-		maybePanic := recover()
-		screen.Fini()
-		if maybePanic != nil {
-			panic(maybePanic)
-		}
-	}
-	defer quit()
 
 	for {
-		screen.Show()
+
+		// Clean the screen
+		screen.Clear()
+
+		// Poll for an event
 		ev := screen.PollEvent()
+
+		// Fetch the type, and check if any other actions are required.
 		switch ev := ev.(type) {
 		case *tcell.EventResize:
 			x, y := screen.Size()
-			drawBox(screen, 0, 0, x-1, y-1, defaultStyle)
+			drawBox(screen, 0, 0, x-1, y-1, style)
-			fmt.Println("size=ok:", checkSize(screen))
+			updateScore(screen, style, snakex)
 			screen.Sync()
 		case *tcell.EventKey:
 			//fmt.Println("Key: ",ev.Rune())
@@ -108,6 +74,23 @@ func main() {
 			} else if ev.Rune() == 'C' || ev.Rune() == 'c' {
 				screen.Clear()
 			}
+		default:
+			time.Sleep(500 * time.Millisecond)
+
 		}
+
+		drawBox(screen, 0, 0, x-1, y-1, style)
+		updateScore(screen, style, snakex)
+		updateSnakePos(&snakex, &snakey)
+		drawSnake(screen, style, snakex, snakey)
+
+		// Draw the screen
+		screen.Show()
+
+		if snakex > 75 {
+			return
+		}
+
 	}
+
 }

main.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"log"
+)
+
+func main() {
+
+	screen, style, err := initilize()
+	if err != nil {
+		log.Fatalln("Initlization error: ", err)
+	}
+
+	game_director(screen, style)
+
+	quit(screen)
+
+}

render.go

@@ -1,6 +1,10 @@
 package main
 
-import "github.com/gdamore/tcell/v2"
+import (
+	"strconv"
+
+	"github.com/gdamore/tcell/v2"
+)
 
 /*
 func renderScreen(&screen tcell.Screen, event tcell.Event, score int) {
@@ -21,3 +25,50 @@ func checkSize(screen tcell.Screen) bool {
 	}
 	return retval
 }
+
+func updateScore(screen tcell.Screen, style tcell.Style, score int) {
+	var x, y int
+	_, y = screen.Size()
+	x = 5
+	for _, r := range []rune("[ Score: " + strconv.FormatInt(int64(score), 10) + " ]") {
+		screen.SetContent(x, y-1, r, nil, style)
+		x++
+	}
+}
+
+func drawBox(s tcell.Screen, x1, y1, x2, y2 int, style tcell.Style) {
+	if y2 < y1 {
+		y1, y2 = y2, y1
+	}
+	if x2 < x1 {
+		x1, x2 = x2, x1
+	}
+
+	// Fill background
+	for row := y1; row <= y2; row++ {
+		for col := x1; col <= x2; col++ {
+			s.SetContent(col, row, ' ', nil, style)
+		}
+	}
+
+	// Draw borders
+	for col := x1; col <= x2; col++ {
+		s.SetContent(col, y1, '═', nil, style)
+		s.SetContent(col, y2, '═', nil, style)
+	}
+	for row := y1 + 1; row < y2; row++ {
+		s.SetContent(x1, row, '║', nil, style)
+		s.SetContent(x2, row, '║', nil, style)
+	}
+
+	// Only draw corners if necessary
+	if y1 != y2 && x1 != x2 {
+		s.SetContent(x1, y1, '╔', nil, style)
+		s.SetContent(x2, y1, '╗', nil, style)
+		s.SetContent(x1, y2, '╚', nil, style)
+		s.SetContent(x2, y2, '╝', nil, style)
+	}
+
+	//drawText(s, x1+1, y1+1, x2-1, y2-1, style, text)
+	updateScore(s, style, 10)
+}

snake.go

@@ -0,0 +1,13 @@
+package main
+
+import (
+	"github.com/gdamore/tcell/v2"
+)
+
+func updateSnakePos(x *int, y *int) {
+	*x = *x + 1
+}
+
+func drawSnake(screen tcell.Screen, style tcell.Style, x int, y int) {
+	screen.SetContent(x, y, '🐍', nil, style)
+}