inventory ui transition wip

src/net/torvald/terrarum/ui/UIItemTransitionContainer.kt

@@ -0,0 +1,95 @@
+package net.torvald.terrarum.ui
+
+import com.badlogic.gdx.Gdx
+import com.badlogic.gdx.graphics.Camera
+import com.badlogic.gdx.graphics.Color
+import com.badlogic.gdx.graphics.g2d.SpriteBatch
+import net.torvald.terrarum.AppLoader
+
+open class UIItemTransitionContainer(
+        parent: UICanvas,
+        initialX: Int,
+        initialY: Int,
+        override val width: Int,
+        override val height: Int,
+        val transitionLength: Float = 0.212f,
+        var currentPosition: Float = 0f,
+        val uis: Array<out UICanvas>
+) : UIItem(parent, initialX, initialY) {
+
+    val debugvals = true
+
+    private var transitionRequested = false
+    private var transitionOngoing = false
+    private var transitionReqSource = currentPosition
+    private var transitionReqTarget = currentPosition
+    private var transitionTimer = 0f
+
+    private val epsilon = 0.001f
+
+    fun requestTransition(target: Int) {
+        if (!transitionOngoing) {
+            transitionRequested = true
+            transitionReqSource = Math.round(currentPosition).toFloat()
+            transitionReqTarget = target.toFloat()
+        }
+    }
+
+    override fun update(delta: Float) {
+        super.update(delta)
+
+        uis.forEachIndexed { index, ui ->
+            if (currentPosition > index - 1 + epsilon && currentPosition < index + 1 - epsilon) {
+                ui.update(delta)
+            }
+        }
+    }
+
+    open fun onTransition(currentPosition: Float, uis: Array<out UICanvas>) {}
+
+    override fun render(batch: SpriteBatch, camera: Camera) {
+        super.render(batch, camera)
+
+        if (transitionRequested && !transitionOngoing) {
+            transitionRequested = false
+            transitionOngoing = true
+            transitionTimer = 0f
+        }
+
+        if (transitionOngoing) {
+            transitionTimer += Gdx.graphics.rawDeltaTime
+
+            currentPosition = UIUtils.moveLinear(transitionReqSource, transitionReqTarget, transitionTimer, transitionLength)
+
+            if (transitionTimer > transitionLength) {
+                transitionOngoing = false
+                currentPosition = transitionReqTarget
+            }
+
+            onTransition(currentPosition, uis)
+        }
+
+        uis.forEachIndexed { index, ui ->
+            if (currentPosition > index - 1 + epsilon && currentPosition < index + 1 - epsilon) {
+                ui.setAsOpen()
+                ui.render(batch, camera)
+
+                if (debugvals) {
+                    AppLoader.fontSmallNumbers.draw(batch, "$index", 300f + (20 * index), 10f)
+                }
+            }
+            else {
+                ui.setAsClose()
+            }
+        }
+
+        if (debugvals) {
+            batch.color = Color.WHITE
+            AppLoader.fontSmallNumbers.draw(batch, "position:$currentPosition", 500f, 10f)
+        }
+    }
+
+    override fun dispose() {
+        uis.forEach { it.dispose() }
+    }
+}