Added rendering stuff, updated go mod

internal/renderer/renderer.go

@@ -1,7 +1,195 @@
 package renderer
 
-import "fmt"
+import (
+	"fmt"
+	"os"
+	"sshpong/internal/ansii"
+	"strings"
+	"time"
+	"unicode/utf8"
+)
 
-func render() {
-	fmt.Println("Test")
+var (
+	targetFps            float64 = 60.0
+	targetFpMilli        float64 = float64(targetFps) / 1000.0
+	millisecondTimeFrame float64 = float64(1 / targetFpMilli)
+	quit                 chan bool
+	userInput            chan rune
+	playerX              int = 10
+	playerY              int = 10
+)
+
+func Render() {
+	now := time.Now()
+	err := doFpsTest()
+	if err != nil {
+		fmt.Println("Error ", err)
+		return
+	}
+	then := time.Now()
+
+	total := float64(float64(then.UnixMicro()-now.UnixMicro()) / 1000.0)
+	fmt.Printf("\n\nTook %.3f milliseconds\n", total)
+}
+
+func writeCheckerBoard(height int, width int, builder *strings.Builder) {
+	for i := 0; i < height; i++ {
+		for j := 0; j < width; j++ {
+			if i%2 == 0 {
+				if j%2 == 0 {
+					builder.WriteString("█")
+				} else {
+
+					builder.WriteString(" ")
+				}
+			} else {
+				if j%2 == 0 {
+					builder.WriteString(" ")
+				} else {
+					builder.WriteString("█")
+				}
+			}
+		}
+	}
+}
+
+func drawScreen(frameNum int, startMs float64) (frameTimeMs float64) {
+	_ = frameNum
+	_, height := ansii.GetTermSize()
+	var builder = strings.Builder{}
+	builder.WriteString(string(ansii.Screen.ClearScreen))
+	// writeCheckerBoard(height, width, &builder)
+	// var xOffset = frameNum % width
+	// ansii.DrawBox(&builder, ansii.Offset{X: 0, Y: 0}, 5, 8, ansii.Colors.Purple)
+	ansii.DrawBox(&builder, ansii.Offset{X: playerX, Y: playerY}, 5, 1, ansii.Colors.Cyan)
+	ansii.DrawPixelStyle(&builder, ansii.Offset{X: playerX, Y: playerY}, ansii.Colors.Purple)
+	ansii.DrawPixelStyle(&builder, ansii.Offset{X: playerX, Y: playerY + 5}, ansii.Colors.Purple)
+	// Quit instructions
+	builder.WriteString(string(ansii.Screen.PlaceCursor(ansii.Offset{X: 0, Y: height})))
+	builder.WriteString("q to quit")
+
+	os.Stdout.WriteString(builder.String())
+	var frameTimeMilli = (float64(time.Now().UnixNano()) / 1_000_000.0) - startMs
+	// builder.WriteString(string(ansii.Screen.Coordinate(0, 0)))
+	return frameTimeMilli
+}
+
+func drawFrameStats(frameNum int, frameTimeMs float64) {
+	width, height := ansii.GetTermSize()
+	var spareTimeMilli = millisecondTimeFrame - frameTimeMs
+	os.Stdout.WriteString(string(ansii.Screen.PlaceCursor(ansii.Offset{X: width - 12, Y: height - 2})))
+	os.Stdout.WriteString(fmt.Sprintf("Frame #: %d", frameNum))
+	os.Stdout.WriteString(string(ansii.Screen.PlaceCursor(ansii.Offset{X: width - 19, Y: height - 1})))
+	os.Stdout.WriteString(fmt.Sprintf("Frame Time: %.4fms", frameTimeMs))
+	os.Stdout.WriteString(string(ansii.Screen.PlaceCursor(ansii.Offset{X: width - 20, Y: height})))
+	os.Stdout.WriteString(fmt.Sprintf("Spare Time: %.4fms", spareTimeMilli))
+}
+
+func handleInput(rawInput rune) {
+	action := ProcessInput(rawInput)
+	width, height := ansii.GetTermSize()
+
+	switch action {
+	case Quit:
+		fmt.Println("Quitting...")
+		close(quit)
+	case Left, LeftArrow:
+		playerX = max(playerX-1, 0)
+	case Right, RightArrow:
+		playerX = min(playerX+1, width)
+	case Up, UpArrow:
+		playerY = max(playerY-1, 0)
+	case Down, DownArrow:
+		playerY = min(playerY+1, height)
+	case Unknown:
+	default:
+		os.Stdout.WriteString(string(ansii.Screen.PlaceCursor(ansii.Offset{X: 0, Y: height - 2})))
+		os.Stdout.WriteString("Unrecognized Input: " + string(action))
+		close(quit)
+	}
+}
+
+func waitForFpsLock(startMs float64) {
+	for {
+		var nowMs = float64(time.Now().UnixNano()) / 1_000_000.0
+		if nowMs-startMs >= millisecondTimeFrame {
+			break
+		}
+	}
+}
+
+func doFpsTest() error {
+	prev, err := ansii.MakeTermRaw()
+	if err != nil {
+		return err
+	}
+	defer ansii.RestoreTerm(prev)
+	quit = make(chan bool, 1)
+	userInput = make(chan rune, 1)
+
+	// User input loop
+	go func() {
+		for {
+			buf := make([]byte, 3)
+			n, err := os.Stdin.Read(buf)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "Error reading from stdin: %v\n", err)
+				continue
+			}
+
+			if n > 0 {
+				if buf[0] == 0x1b { // ESC
+					if n > 1 && buf[1] == '[' { // ESC [
+						switch buf[2] {
+						case 'A':
+							userInput <- '↑' // Up arrow
+						case 'B':
+							userInput <- '↓' // Down arrow
+						case 'C':
+							userInput <- '→' // Right arrow
+						case 'D':
+							userInput <- '←' // Left arrow
+						default:
+							userInput <- '?'
+						}
+					} else {
+						userInput <- '?'
+					}
+				} else {
+					r, _ := utf8.DecodeRune(buf)
+					userInput <- r
+				}
+			}
+		}
+	}()
+	// Rendering loop
+	go func() {
+		for i := 0; i <= 10_000; i++ {
+			startMs := float64(time.Now().UnixNano()) / 1_000_000.0
+			select {
+			case <-quit:
+				return
+			default:
+				frameTimeMs := drawScreen(i, startMs)
+				drawFrameStats(i, frameTimeMs)
+				waitForFpsLock(startMs)
+			}
+		}
+		close(quit)
+	}()
+
+	os.Stdout.WriteString(string(ansii.Screen.HideCursor))
+	defer os.Stdout.WriteString(string(ansii.Screen.ShowCursor))
+	for {
+		select {
+		case <-quit:
+			fmt.Println("Exiting")
+			return nil
+		// case ui := <-userInput:
+		case input := <-userInput:
+			handleInput(input)
+		// fmt.Println(ui)
+		default:
+		}
+	}
 }

internal/renderer/user_inputs.go

@@ -0,0 +1,25 @@
+package renderer
+
+type UiAction rune
+
+const (
+	Unknown    UiAction = iota
+	Quit       UiAction = 81 // 'Q'
+	Left       UiAction = 65
+	Up         UiAction = 87
+	Right      UiAction = 68
+	Down       UiAction = 83
+	LeftArrow  UiAction = 8592
+	UpArrow    UiAction = 8593
+	RightArrow UiAction = 8594
+	DownArrow  UiAction = 8595
+)
+
+func ProcessInput(rawInput rune) (action UiAction) {
+	inputVal := int(rawInput)
+	// Convert to UpperCase
+	if inputVal >= 97 && inputVal <= 122 {
+		inputVal = inputVal - 32
+	}
+	return UiAction(inputVal)
+}