Add delta value between frames

game/game.go

@@ -23,26 +23,26 @@ func Run(root *node.Node, renderer rendering.Renderer2D, inputHandler input.Inpu
 
 	rotation_speed := 0.01
 	speed := 0.02
-	g.OnUpdate(func() error {
+	g.OnUpdate(func(delta float64) error {
 
 		if inputHandler.IsKeyJustReleased(sdl.SCANCODE_SPACE) {
 			rotation_speed = -rotation_speed
 		}
 
 		if inputHandler.IsKeyDown(sdl.SCANCODE_D) {
-			g.Position.X += speed
+			g.Position.X += speed * delta
 		}
 		if inputHandler.IsKeyDown(sdl.SCANCODE_A) {
-			g.Position.X -= speed
+			g.Position.X -= speed * delta
 		}
 		if inputHandler.IsKeyDown(sdl.SCANCODE_S) {
-			g.Position.Y += speed
+			g.Position.Y += speed * delta
 		}
 		if inputHandler.IsKeyDown(sdl.SCANCODE_W) {
-			g.Position.Y -= speed
+			g.Position.Y -= speed * delta
 		}
 
-		g.Rotation += rotation_speed
+		g.Rotation += rotation_speed * delta
 		return nil
 	})
 
@@ -51,7 +51,7 @@ func Run(root *node.Node, renderer rendering.Renderer2D, inputHandler input.Inpu
 	controller.SetProcessMode(node.ActiveProcessMode)
 	defer root.AddChild(&controller)
 
-	controller.OnUpdate(func() error {
+	controller.OnUpdate(func(float64) error {
 		if inputHandler.IsKeyJustPressed(sdl.SCANCODE_ESCAPE) {
 			if g.IsProcessing() {
 				g.SetProcessMode(node.PausedProcessMode)

go.mod

@@ -2,4 +2,4 @@ module github.com/manleydev/golang-game-framework
 
 go 1.18
 
-require github.com/veandco/go-sdl2 v0.4.21
+require github.com/veandco/go-sdl2 v0.4.25

go.sum

@@ -2,3 +2,5 @@ github.com/veandco/go-sdl2 v0.4.21 h1:85AtFYv3vSPZvyOOxkJ03sHoJe8ESjPSZLr0KueQtV
 github.com/veandco/go-sdl2 v0.4.21/go.mod h1:OROqMhHD43nT4/i9crJukyVecjPNYYuCofep6SNiAjY=
 github.com/veandco/go-sdl2 v0.4.24 h1:J+OCnPp0yfas4DAG13e3kIgC84mNxWGa3gpWYxrQQfI=
 github.com/veandco/go-sdl2 v0.4.24/go.mod h1:OROqMhHD43nT4/i9crJukyVecjPNYYuCofep6SNiAjY=
+github.com/veandco/go-sdl2 v0.4.25 h1:J5ac3KKOccp/0xGJA1PaNYKPUcZm19IxhDGs8lJofPI=
+github.com/veandco/go-sdl2 v0.4.25/go.mod h1:OROqMhHD43nT4/i9crJukyVecjPNYYuCofep6SNiAjY=

input/input_handler.go

@@ -4,5 +4,5 @@ type InputHandler interface {
 	IsKeyDown(uint) bool
 	IsKeyJustPressed(uint) bool
 	IsKeyJustReleased(uint) bool
-	Update() error
+	Update(delta float64) error
 }

main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"log"
+	"time"
 
 	"github.com/manleydev/golang-game-framework/game"
 	"github.com/manleydev/golang-game-framework/input"
@@ -27,16 +28,18 @@ func main() {
 	game.Run(&root, renderer, input)
 
 	running := true
+	var lastTimestamp int64 = time.Now().UnixMicro()
+	var delta float64 = 0.0
 	for running {
 
-		if err := root.Update(); err != nil {
+		if err := root.Update(delta); err != nil {
 			log.Fatal("Update: ", err)
 		}
-		if err := input.Update(); err != nil {
+		if err := input.Update(delta); err != nil {
 			log.Fatal("Input Update: ", err)
 		}
 
-		if err := renderer.Update(); err != nil {
+		if err := renderer.Update(delta); err != nil {
 			log.Fatal("Renderer Update: ", err)
 		}
 
@@ -47,5 +50,9 @@ func main() {
 			log.Fatal("Renderer Draw: ", err)
 		}
 
+		newTimestamp := time.Now().UnixMicro()
+		delta = float64(lastTimestamp) / float64(newTimestamp)
+		lastTimestamp = newTimestamp
+
 	}
 }

node/camera2d.go

@@ -13,8 +13,8 @@ type Camera2D struct {
 	renderer *rendering.Renderer2D
 }
 
-func (camera *Camera2D) Update() error {
-	if err := camera.Node2D.Update(); err != nil {
+func (camera *Camera2D) Update(delta float64) error {
+	if err := camera.Node2D.Update(delta); err != nil {
 		return err
 	}
 

node/inode.go

@@ -10,7 +10,7 @@ const (
 
 type INode interface {
 	GetName() string
-	Update() error
+	Update(delta float64) error
 	ready(INode) error
 	IsProcessing() bool
 	GetProcessMode() ProcessMode

node/node.go

@@ -14,7 +14,7 @@ type Node struct {
 	processMode ProcessMode
 
 	onReadyMethods  []func() error
-	onUpdateMethods []func() error
+	onUpdateMethods []func(float64) error
 	onDraw2dMethods []func(rendering.Renderer2D) error
 }
 
@@ -36,16 +36,16 @@ func (node *Node) OnReady(callback func() error) {
 	node.onReadyMethods = append(node.onReadyMethods, callback)
 }
 
-func (node *Node) Update() error {
+func (node *Node) Update(delta float64) error {
 	for _, child := range node.children {
-		if err := child.Update(); err != nil {
+		if err := child.Update(delta); err != nil {
 			return err
 		}
 	}
 
 	if node.IsProcessing() {
 		for _, updateMethod := range node.onUpdateMethods {
-			if err := updateMethod(); err != nil {
+			if err := updateMethod(delta); err != nil {
 				return err
 			}
 		}
@@ -54,7 +54,7 @@ func (node *Node) Update() error {
 	return nil
 }
 
-func (node *Node) OnUpdate(callback func() error) {
+func (node *Node) OnUpdate(callback func(float64) error) {
 	if callback == nil {
 		return
 	}

rendering/render2d.go

@@ -8,7 +8,7 @@ type Renderer2D interface {
 	DrawTexture2D(DrawTexture2DInput) error
 
 	Draw() error
-	Update() error
+	Update(delta float64) error
 	Destroy()
 	SetCamera(*Camera2D) error
 }

sdl/input_handler.go

@@ -37,7 +37,7 @@ func (input *SdlInputHandler) IsKeyJustReleased(key uint) bool {
 	return false
 }
 
-func (input *SdlInputHandler) Update() error {
+func (input *SdlInputHandler) Update(delta float64) error {
 	copy(input.lastKeyState, input.keyState)
 	input.keyState = sdl.GetKeyboardState()
 

sdl/render2d.go

@@ -69,7 +69,7 @@ func (w *SdlRenderer2D) SetCamera(camera *rendering.Camera2D) error {
 	return nil
 }
 
-func (w *SdlRenderer2D) Update() error {
+func (w *SdlRenderer2D) Update(delta float64) error {
 	for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
 		switch event.(type) {
 		case *sdl.QuitEvent: