Moveable viewport. Absolute positioning (for UI etc) is possible. Added distance-based bounder for projectiles etc as 'screen' is no longer a suitable bounder. Removed debug msg.

component_animator.go

@@ -9,7 +9,6 @@ package GoRetro
 
 import (
 	"encoding/json"
-	"fmt"
 	"os"
 	"time"
 
@@ -65,12 +64,16 @@ func (an *animator) onUpdate() error {
 }
 
 func (an *animator) onDraw() error {
+	Position := an.container.Position
+	if !an.container.PositionAbsolute {
+		Position = vectorAdd(an.container.Position, ViewPort.Position)
+	}
 
 	return drawTexture(
 		an.tex,
 		VectorInt32{an.sequences[an.current].frames[an.sequences[an.current].frame].W, an.sequences[an.current].frames[an.sequences[an.current].frame].H},
 		VectorInt32{an.sequences[an.current].frames[an.sequences[an.current].frame].X, an.sequences[an.current].frames[an.sequences[an.current].frame].Y},
-		an.container.Position,
+		Position,
 		an.container.Rotation,
 		an.container.Renderer)
 }
@@ -131,8 +134,6 @@ func NewSequence(
 	}
 	defer jsonFile.Close()
 
-	fmt.Println(seq.frames)
-
 	seq.frame = 0
 	seq.sampleRate = sampleRate
 	seq.loop = loop

component_bounder_distance.go

@@ -0,0 +1,40 @@
+package GoRetro
+
+/*
+ * --------------------
+ * BounderDistance
+ * --------------------
+ * A bounder which triggers if the distance from spawn to current exceeds range
+ */
+
+type bounderDistance struct {
+	container    *Element
+	callbackFunc func(element *Element)
+	maxrange     float64
+}
+
+func NewBounderDistance(container *Element, callback func(element *Element), maxrange float64) *bounderDistance {
+	return &bounderDistance{
+		container:    container,
+		callbackFunc: callback,
+		maxrange:     maxrange,
+	}
+}
+
+func (bounder *bounderDistance) onDraw() error {
+	return nil
+}
+
+func (bounder *bounderDistance) onUpdate() error {
+	b := bounder.container
+
+	if vectorDistance(b.Position, b.SpawnPosition) > bounder.maxrange {
+		bounder.callbackFunc(bounder.container)
+	}
+
+	return nil
+}
+
+func (bounder *bounderDistance) onCollision(other *Element) error {
+	return nil
+}

component_bounder_screen.go

@@ -1,10 +1,13 @@
 package GoRetro
 
+import "fmt"
+
 /*
  * --------------------
  * BounderScreen
  * --------------------
  * A bounder which triggers if the element isn't on the screen
+ * TODO: Use dimensions of the entity
  */
 
 type bounderScreen struct {
@@ -13,6 +16,10 @@ type bounderScreen struct {
 }
 
 func NewBounderScreen(container *Element, callback func(element *Element)) *bounderScreen {
+	if !container.PositionAbsolute {
+		fmt.Println("Added screen bounder to non-absolute positioned element")
+	}
+
 	return &bounderScreen{
 		container:    container,
 		callbackFunc: callback,
@@ -26,8 +33,8 @@ func (bounder *bounderScreen) onDraw() error {
 func (bounder *bounderScreen) onUpdate() error {
 	b := bounder.container
 
-	if b.Position.X > float64(Config.ScreenWidth) || b.Position.X < 0 ||
-		b.Position.Y > float64(Config.ScreenHeight) || b.Position.Y < 0 {
+	if b.Position.X > float64(Config.WindowSize.X) || b.Position.X < 0 ||
+		b.Position.Y > float64(Config.WindowSize.Y) || b.Position.Y < 0 {
 		bounder.callbackFunc(bounder.container)
 	}
 

component_sprite_renderer.go

@@ -46,11 +46,16 @@ func (sr *spriteRenderer) onUpdate() error {
 }
 
 func (sr *spriteRenderer) onDraw() error {
+	Position := sr.container.Position
+	if !sr.container.PositionAbsolute {
+		Position = vectorAdd(sr.container.Position, ViewPort.Position)
+	}
+
 	return drawTexture(
 		sr.tex,
 		VectorInt32{-1, -1},
 		VectorInt32{0, 0},
-		sr.container.Position,
+		Position,
 		sr.container.Rotation,
 		sr.container.Renderer)
 }

component_spritesheet_renderer.go

@@ -42,11 +42,16 @@ func (sr *spriteSheetRenderer) onUpdate() error {
 }
 
 func (sr *spriteSheetRenderer) onDraw() error {
+	Position := ViewPort.Position
+	if !sr.container.PositionAbsolute {
+		Position = vectorAdd(sr.container.Position, ViewPort.Position)
+	}
+
 	return drawTexture(
 		sr.tex,
 		sr.size,
 		sr.sheetposition,
-		sr.container.Position,
+		Position,
 		sr.container.Rotation,
 		sr.container.Renderer)
 }

element.go

@@ -14,16 +14,18 @@ type component interface {
 }
 
 type Element struct {
-	Renderer       *sdl.Renderer
-	Position       Vector
-	Rotation       float64
-	Active         bool
-	Delete         bool
-	Collisions     []Circle
-	components     []component
-	parentElement  *Element
-	ZIndex         int
-	CollisionLayer int
+	Renderer         *sdl.Renderer
+	Position         Vector
+	SpawnPosition    Vector
+	PositionAbsolute bool
+	Rotation         float64
+	Active           bool
+	Delete           bool
+	Collisions       []Circle
+	components       []component
+	parentElement    *Element
+	ZIndex           int
+	CollisionLayer   int
 }
 
 var Elements []*Element

goretro.go

@@ -7,10 +7,13 @@ import (
 	"github.com/veandco/go-sdl2/sdl"
 )
 
-var Config struct {
-	ScreenWidth  int32
-	ScreenHeight int32
+var ViewPort struct {
+	Size     Vector
+	Position Vector
+}
 
+var Config struct {
+	WindowSize             VectorInt32
 	TargetTicksPerSecond   float64
 	DebugStatePrintSeconds float64
 
@@ -27,12 +30,12 @@ func Init() (*sdl.Renderer, *sdl.Window) {
 		return nil, nil
 	}
 
-	fmt.Printf("%d x %d", Config.ScreenWidth, Config.ScreenHeight)
+	fmt.Printf("%d x %d", Config.WindowSize.X, Config.WindowSize.Y)
 
 	window, err := sdl.CreateWindow(
 		"GoEscape",
 		sdl.WINDOWPOS_UNDEFINED, sdl.WINDOWPOS_UNDEFINED,
-		Config.ScreenWidth, Config.ScreenHeight,
+		Config.WindowSize.X, Config.WindowSize.Y,
 		sdl.WINDOW_OPENGL)
 	if err != nil {
 		fmt.Println("initializing window:", err)
@@ -116,9 +119,10 @@ func Tick(renderer *sdl.Renderer) bool {
 	Elements = Elements[:len(Elements)-truncate]
 
 	if DebugTick {
+		fmt.Printf("\n\n--\n")
 		fmt.Printf("TPS: %d\n", 1000000/(time.Since(frameStartTime).Microseconds()+1))
 		fmt.Printf("Elements: %d\n", len(Elements))
-
+		fmt.Printf("Viewport: %f %f %f %f\n", ViewPort.Position.X, ViewPort.Position.Y, ViewPort.Size.X, ViewPort.Size.Y)
 	}
 
 	Delta = time.Since(frameStartTime).Seconds() * Config.TargetTicksPerSecond