allow moving objects

2 files changed, 68 insertions, 8 deletions

diff --git a/main.go b/main.go
index 9abf997..04828a7 100644
--- a/main.go
+++ b/main.go
@@ -11,8 +11,11 @@ import (
 	"github.com/hajimehoshi/ebiten/v2"
 	"github.com/hajimehoshi/ebiten/v2/ebitenutil"
 	"github.com/hajimehoshi/ebiten/v2/inpututil"
+
 )
 
+
+
 const (
     screenWidth = 400
     screenHeight = 240
@@ -125,7 +128,6 @@ func (g * Game)ReplayPlayerAi() {
         g.KillPlayer()
     }
 
-    fmt.Printf("pframe %d/%d\n", g.playerAiIdx, len(g.playerAi))
 }
 
 func (g * Game)ReplayPoint() {
@@ -261,24 +263,24 @@ func (g *Game) Update() error {
         for _, obj := range g.objects {
             obj.Update(*g.tilemap, g.objects)
         }
+
         g.tilemap.Update()
         g.ReplayPlayerAi()
 
+        cx, cy := ebiten.CursorPosition()
+
         if len(g.toPlace) > 0 {
             placeable := g.toPlace[0]
-            cx, cy := ebiten.CursorPosition()
             cx = int(math.Floor(float64(cx)/float64(g.tilemap.tileSize)))*g.tilemap.tileSize
             cy = int(math.Floor(float64(cy)/float64(g.tilemap.tileSize)))*g.tilemap.tileSize
 
             cx += placeable.offsetX
             cy += placeable.offsetY
-
             placeable.x = float32(cx)
             placeable.y = float32(cy)
-
-            if inpututil.IsMouseButtonJustPressed(ebiten.MouseButton0) {
-                g.PlaceObject(cx, cy)
-            }
+        }
+        if inpututil.IsMouseButtonJustPressed(ebiten.MouseButton0) {
+            g.PlaceObject(cx, cy)
         }
     }
     if g.player.y > screenHeight {
@@ -290,6 +292,17 @@ func (g *Game) Update() error {
 }
 
 func (g *Game) PlaceObject(cx, cy int) {
+        if len(g.toPlace) == 0 {
+            object := GetObjectAt(g.objects, float32(cx), float32(cy))
+            if object != nil {
+                if object.movable {
+                    g.toPlace = append([]*GameObject{object}, g.toPlace...)
+                    g.RemoveObject(object)
+                }
+            }
+            return
+        }
+
         placeable := g.toPlace[0]
         if placeable.HasCollision(*g.tilemap, g.objects, NONE) {
             return
@@ -330,7 +343,6 @@ func (g *Game) Draw(screen *ebiten.Image) {
 
         // AFTER THE END
         if g.time > g.animStart + 60 {
-            fmt.Printf("end of end state transition\n")
             g.TransitionState()
         }
     }
@@ -387,6 +399,10 @@ func (g *Game) KillPlayer() {
             g.ResetAll()
             g.playerAi = g.playerAi[:0]
             g.state = IN_GAME
+
+            for _, o := range g.objects {
+                o.movable = false
+            }
         }
     }
 }
@@ -400,6 +416,24 @@ func (g *Game) EndLevel() {
     }
 }
 
+func (g *Game)RemoveObject(obj *GameObject) {
+
+    i := 0 // output index
+    for _, x := range g.objects {
+        if x != obj {
+            // copy and increment index
+            g.objects[i] = x
+            i++
+        }
+    }
+    // Prevent memory leak by erasing truncated values 
+    // (not needed if values don't contain pointers, directly or indirectly)
+    for j := i; j < len(g.objects); j++ {
+        g.objects[j] = nil
+    }
+    g.objects = g.objects[:i]
+}
+
 func main() {
     LoadShaders()
 
diff --git a/objects.go b/objects.go
index 0c24beb..b301495 100644
--- a/objects.go
+++ b/objects.go
@@ -3,7 +3,9 @@ package main
 import (
 	"log"
     "image"
+    "image/color"
     "github.com/hajimehoshi/ebiten/v2"
+    "github.com/hajimehoshi/ebiten/v2/vector"
 	"github.com/hajimehoshi/ebiten/v2/ebitenutil"
 )
 
@@ -37,6 +39,7 @@ type GameObject struct {
     onCollideDown func(this, other *GameObject) bool
     onCollideLeft func(this, other *GameObject) bool
     onCollideRight func(this, other *GameObject) bool
+    movable bool
 }
 
 
@@ -82,6 +85,19 @@ func (o * GameObject) Update(tilemap Tilemap, others []*GameObject) {
         o.onGround = false;
     }
 }
+func GetObjectAt(objects []*GameObject, x, y float32) *GameObject {
+
+    for _, object := range objects {
+        maxX := object.x + float32(object.image.Bounds().Dx())
+        maxY := object.y + float32(object.image.Bounds().Dy())
+        minX := object.x
+        minY := object.y
+        if x >= minX && x < maxX && y >= minY && y < maxY {
+            return object
+        }
+    }
+    return nil
+}
 
 func (o * GameObject) HasCollision(tilemap Tilemap, others []*GameObject, dir Direction) bool {
     if tilemap.CollideObject(o) {
@@ -114,6 +130,13 @@ func (o * GameObject) Draw(screen *ebiten.Image, tilemap Tilemap) {
     op := &ebiten.DrawImageOptions{}
     op.GeoM.Translate(float64(o.x), float64(o.y))
     screen.DrawImage(o.image, op)
+
+    
+    if o.movable {
+        vector.StrokeRect(screen, o.x, o.y, float32(o.image.Bounds().Dx()), float32(o.image.Bounds().Dy()), 2, color.RGBA{255, 100, 100, 255}, false)
+    }
+
+
 }
 
 func (object * GameObject) Collide(other *GameObject) bool {
@@ -171,6 +194,7 @@ func NewObject(game *Game, x, y float32) *GameObject{
     obj.resistance = airResistance
     obj.x = obj.startx
     obj.y = obj.starty
+    obj.movable = true
     return obj
 }
 
@@ -184,6 +208,7 @@ func NewPlayer(game *Game, x, y float32) *GameObject{
 
     player.image = playerImage.SubImage(image.Rect(4, 8, 27, 32)).(*ebiten.Image)
 
+    player.movable = false
     return player
 }
 
@@ -196,6 +221,7 @@ func NewExit(game *Game, x, y float32) *GameObject{
     exit.onCollideLeft = OnCollideExit
     exit.onCollideRight = OnCollideExit
 
+    exit.movable = false
     return exit
 }