more Kotlin, UIs now can open/close with animation, working world time with skybox colour changing (sunlight transition is still WIP), fixed project library settings so that the suggestion in IntelliJ IDEA would work properly

Former-commit-id: 82c857164f2636ad943d5a43f0690a3431ab0f26
Former-commit-id: 7c8b70e6b267f7c5c050d7d0902278739ec18b44

src/com/Torvald/ColourUtil/Col216.kt

@@ -0,0 +1,82 @@
+package com.Torvald.ColourUtil
+
+import org.newdawn.slick.Color
+
+/**
+ * 6-Step RGB with builtin utils.
+ * Created by minjaesong on 16-02-11.
+ */
+class Col216 : LimitedColours {
+
+    var raw: Byte = 0
+        private set
+
+    /**
+
+     * @param data
+     */
+    constructor(data: Byte) {
+        create(data.toInt())
+    }
+
+    /**
+
+     * @param r 0-5
+     * *
+     * @param g 0-5
+     * *
+     * @param b 0-5
+     */
+    constructor(r: Int, g: Int, b: Int) {
+        create(r, g, b)
+    }
+
+    override fun createSlickColor(raw: Int): Color {
+        assertRaw(raw)
+        val r = raw / MUL_2
+        val g = raw % MUL_2 / MUL
+        val b = raw % MUL
+
+        return createSlickColor(r, g, b)
+    }
+
+    override fun createSlickColor(r: Int, g: Int, b: Int): Color {
+        assertRGB(r, g, b)
+        return Color(LOOKUP[r], LOOKUP[g], LOOKUP[b])
+    }
+
+    override fun create(raw: Int) {
+        assertRaw(raw)
+        this.raw = raw.toByte()
+    }
+
+    override fun create(r: Int, g: Int, b: Int) {
+        assertRGB(r, g, b)
+        raw = (MUL_2 * r + MUL * g + b).toByte()
+    }
+
+    private fun assertRaw(i: Int) {
+        if (i >= COLOUR_DOMAIN_SIZE || i < 0) {
+            println("i: " + i.toString())
+            throw IllegalArgumentException()
+        }
+    }
+
+    private fun assertRGB(r: Int, g: Int, b: Int) {
+        if (r !in 0..MAX_STEP || g !in 0..MAX_STEP || b !in 0..MAX_STEP) {
+            println("r: " + r.toString())
+            println("g: " + g.toString())
+            println("b: " + b.toString())
+            throw IllegalArgumentException()
+        }
+    }
+
+    companion object {
+        @Transient private val LOOKUP = intArrayOf(0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF)
+
+        const val MUL = 6
+        const val MUL_2 = MUL * MUL
+        const val MAX_STEP = MUL - 1
+        const val COLOUR_DOMAIN_SIZE = MUL_2 * MUL
+    }
+}