conveyer belt wip

src/net/torvald/terrarum/gameactors/ActorConveyors.kt

@@ -0,0 +1,71 @@
+package net.torvald.terrarum.gameactors
+
+import com.badlogic.gdx.graphics.g2d.SpriteBatch
+import net.torvald.terrarum.TerrarumAppConfiguration.TILE_SIZED
+import kotlin.math.atan2
+import kotlin.math.cos
+import kotlin.math.sin
+
+/**
+ * Created by minjaesong on 2025-03-10.
+ */
+class ActorConveyors : ActorWithBody {
+
+    // make it savegame-reloadable
+    private constructor() {
+        axleX1 = -1
+        axleY1 = -1
+        axleX2 = -1
+        axleY2 = -1
+    }
+
+    val axleX1: Int // can be negative when the conveyor crosses the world border
+    val axleY1: Int
+    val axleX2: Int // always positive
+    val axleY2: Int
+
+    /**
+     * xy1 is always the starting point, and the starting point's x-value is always lower than the end points',
+     * even when the conveyor crosses the edge of the world border, in which case the x-value is negative.
+     */
+    constructor(x1: Int, y1: Int, x2: Int, y2: Int) {
+        axleX1 = x1
+        axleY1 = y1
+        axleX2 = x2
+        axleY2 = y2
+    }
+
+    override fun drawBody(frameDelta: Float, batch: SpriteBatch) {
+        val inclination = atan2(axleY2.toDouble() - axleY1, axleX2.toDouble() - axleX1)
+        val declination = atan2(axleY1.toDouble() - axleY2, axleX1.toDouble() - axleX2)
+
+        val wxSpinCntrStart = (axleX1 + 0.5) * TILE_SIZED
+        val wySpinCntrStart = (axleY1 + 0.5) * TILE_SIZED
+        val wxSpinCntrEnd = (axleX2 + 0.5) * TILE_SIZED
+        val wySpinCntrEnd = (axleY2 + 0.5) * TILE_SIZED
+
+        val r = 0.5 * TILE_SIZED
+
+        val wxBeltTopStart = wxSpinCntrStart + r * sin(inclination)
+        val wyBeltTopStart = wySpinCntrStart + r * cos(inclination)
+        val wxBeltTopEnd = wxSpinCntrEnd + r * sin(inclination)
+        val wyBeltTopEnd = wySpinCntrEnd + r * cos(inclination)
+
+        val wxBeltBtmStart = wxSpinCntrStart + r * sin(declination)
+        val wyBeltBtmStart = wySpinCntrStart + r * cos(declination)
+        val wxBeltBtmEnd = wxSpinCntrEnd + r * sin(declination)
+        val wyBeltBtmEnd = wySpinCntrEnd + r * cos(declination)
+
+
+        // belt top
+        drawLineAtWorld(wxBeltTopStart, wyBeltTopStart, wxBeltTopEnd, wyBeltTopEnd)
+        // belt bottom
+        drawLineAtWorld(wxBeltBtmStart, wyBeltBtmStart, wxBeltBtmEnd, wyBeltBtmEnd)
+        // left arc
+
+        // right arc
+
+
+
+    }
+}