Added Vector2.

core/src/commonMain/kotlin/cn/rdlevel/rdkt/core/data/Vector2.kt

@@ -0,0 +1,74 @@
+@file:OptIn(RDKTInternalAPI::class)
+
+package cn.rdlevel.rdkt.core.data
+
+import cn.rdlevel.rdkt.core.annotations.RDKTInternalAPI
+import cn.rdlevel.rdkt.core.serialization.TransformSerializer
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.builtins.ListSerializer
+import kotlinx.serialization.builtins.serializer
+import kotlin.jvm.JvmSynthetic
+
+/**
+ * Represents a vector in 2D space with x and y components.
+ *
+ * @property x The x component of the vector.
+ * @property y The y component of the vector.
+ */
+@Serializable(Vector2.Serializer::class)
+public data class Vector2(val x: Double, val y: Double) {
+    override fun toString(): String {
+        return "[$x, $y]"
+    }
+
+    /**
+     * Returns a new vector2 with the x component changed to [newX].
+     */
+    public fun withX(newX: Double): Vector2 = copy(x = newX)
+
+    /**
+     * Returns a new vector2 with the y component changed to [newY].
+     */
+    public fun withY(newY: Double): Vector2 = copy(y = newY)
+
+    /**
+     * Returns a new vector2 added by [other].
+     */
+    public operator fun plus(other: Vector2): Vector2 = Vector2(x + other.x, y + other.y)
+
+    /**
+     * Returns a new vector2 subtracted by [other].
+     */
+    public operator fun minus(other: Vector2): Vector2 = Vector2(x - other.x, y - other.y)
+
+    /**
+     * Returns a new vector2 multiplied by [scalar].
+     */
+    public operator fun times(scalar: Double): Vector2 = Vector2(x * scalar, y * scalar)
+
+    /**
+     * Returns a new vector2 divided by [scalar].
+     */
+    public operator fun div(scalar: Double): Vector2 = Vector2(x / scalar, y / scalar)
+
+    public companion object {
+        public val ZERO: Vector2 = Vector2(0.0, 0.0)
+        public val ONE: Vector2 = Vector2(1.0, 1.0)
+    }
+
+    public object Serializer :
+        TransformSerializer<Vector2, List<Double>>("Vector2", ListSerializer(Double.serializer())) {
+        override fun toData(value: Vector2): List<Double> = listOf(value.x, value.y)
+
+        override fun fromData(data: List<Double>): Vector2 {
+            require(data.size == 2) { "Expected list of size 2 for vector2, got ${data.size}" }
+            return Vector2(data[0], data[1])
+        }
+    }
+}
+
+/**
+ * Creates a [Vector2] with the given x and y components.
+ */
+@JvmSynthetic
+public fun vectorOf(x: Double, y: Double): Vector2 = Vector2(x, y)