diff --git a/src/net/torvald/spriteassembler/ADPropertyObject.kt b/src/net/torvald/spriteassembler/ADPropertyObject.kt
new file mode 100644
index 000000000..0292bfdb4
--- /dev/null
+++ b/src/net/torvald/spriteassembler/ADPropertyObject.kt
@@ -0,0 +1,115 @@
+package net.torvald.spriteassembler
+
+import java.io.InputStream
+import java.io.Reader
+import java.util.*
+import kotlin.collections.HashMap
+
+class ADProperties {
+    private val javaProp = Properties()
+
+    /** Every key is CAPITALISED */
+    private val propTable = HashMap<String, List<ADPropertyObject>>()
+
+    constructor(reader: Reader) {
+        javaProp.load(reader)
+        continueLoad()
+    }
+
+    constructor(inputStream: InputStream) {
+        javaProp.load(inputStream)
+        continueLoad()
+    }
+
+    private fun continueLoad() {
+        javaProp.keys.forEach { propName ->
+            val propsStr = javaProp.getProperty(propName as String)
+            val propsList = propsStr.split(';').map { ADPropertyObject(it) }
+
+            propTable[propName.capitalize()] = propsList
+        }
+    }
+
+    operator fun get(identifier: String) = propTable[identifier.capitalize()]
+    val keys
+        get() = propTable.keys
+    fun containsKey(key: String) = propTable.containsKey(key)
+    fun forEach(predicate: (String, List<ADPropertyObject>) -> Unit) = propTable.forEach(predicate)
+}
+
+/**
+ * @param propertyRaw example inputs:
+ * - ```DELAY 0.15```
+ * - ```LEG_RIGHT 0,-1```
+ *
+ * Created by minjaesong on 2019-01-05.
+ */
+class ADPropertyObject(propertyRaw: String) {
+
+    /** If the input is like ```UPPER_TORSO``` (that is, not a variable-input pair), this holds the string UPPER_TORSO. */
+    val variable: String
+    val input: Any?
+        get() = when (type) {
+            ADPropertyType.IVEC2 -> field!! as Vector2i
+            ADPropertyType.FLOAT -> field!! as Float
+            else -> null
+        }
+    val type: ADPropertyType
+
+    init {
+        val propPair = propertyRaw.split(variableInputSepRegex)
+
+        if (isADvariable(propertyRaw)) {
+            variable = propPair[0]
+            val inputStr = propPair[1]!!
+
+            if (isADivec2(inputStr)) {
+                type = ADPropertyType.IVEC2
+                input = toADivec2(inputStr)
+            }
+            else if (isADfloat(inputStr)) {
+                type = ADPropertyType.FLOAT
+                input = toADfloat(inputStr)
+            }
+            else {
+                throw IllegalArgumentException("Malformed input, input property seems not ivec2, float nor string: $propertyRaw")
+            }
+        }
+        else {
+            variable = propertyRaw
+            input = null
+            type = ADPropertyType.STRING
+        }
+    }
+
+    companion object {
+        private val floatRegex = Regex("""-?[0-9]+(\.[0-9]*)?""")
+        private val ivec2Regex = Regex("""-?[0-9]+,-?[0-9]+""")
+        private val variableInputSepRegex = Regex(""" +""")
+
+        fun isADivec2(s: String) = ivec2Regex.matches(s)
+        fun isADfloat(s: String) = floatRegex.matches(s) && !ivec2Regex.containsMatchIn(s)
+
+        fun toADivec2(s: String) = if (isADivec2(s))
+                Vector2i(s.substringBefore(',').toInt(), s.substringAfter(',').toInt())
+            else throw IllegalArgumentException("Input not in ivec2 format: $s")
+        fun toADfloat(s: String) = if (isADfloat(s))
+                s.toFloat()
+            else throw IllegalArgumentException("Input not in ivec2 format: $s")
+
+        /** example valid input: ```LEG_RIGHT 0,1``` */
+        fun isADvariable(property: String) = variableInputSepRegex.containsMatchIn(property)
+        /** example valid input: ```sprites/test.tga``` */
+        fun isADstring(property: String) = !isADvariable(property)
+    }
+
+    data class Vector2i(var x: Int, var y: Int)
+
+    enum class ADPropertyType {
+        STRING, IVEC2, FLOAT
+    }
+
+    override fun toString(): String {
+        return "$variable ${input ?: ""}: $type"
+    }
+}
\ No newline at end of file
diff --git a/src/net/torvald/spriteassembler/ANIMATION_DESCRIPTION_LANGUAGE.md b/src/net/torvald/spriteassembler/ANIMATION_DESCRIPTION_LANGUAGE.md
new file mode 100644
index 000000000..4087fc745
--- /dev/null
+++ b/src/net/torvald/spriteassembler/ANIMATION_DESCRIPTION_LANGUAGE.md
@@ -0,0 +1,97 @@
+## Animation Description Language
+
+This is a text version of my drawing of same name. 2018-01-04 CuriousTorvald
+
+Author's node: yet another non-JSON domain-specific language because why not?
+
+## Objective
+
+* Java .properties-compatible
+* Case insensitive
+
+## Example code
+
+```
+SPRITESHEET=sprites/test
+EXTENSION=.tga.gz
+
+ANIM_RUN=DELAY 0.15;ROW 2
+ANIM_RUN_BODYPARTS=HEAD;UPPER_TORSO;LOWER_TORSO;ARM_FWD_LEFT;ARM_FWD_RIGHT;LEG_LEFT;LEG_RIGHT
+ANIM_RUN_1=LEG_RIGHT 1,-1;LEG_LEFT -1,0
+ANIM_RUN_2=ALL 0,-1;LEG_RIGHT 0,1;LEG_LEFT 0,-1
+ANIM_RUN_3=LEG_RIGHT -1,0;LEG_LEFT 1,-1
+ANIM_RUN_4=ALL 0,-1;LEG_RIGHT 0,-1;LEG_LEFT 0,1
+
+ANIM_IDLE=DELAY 2;ROW 1
+ANIM_IDLE_BODYPARTS=HEAD;UPPER_TORSO;LOWER_TORSO;ARM_REST_LEFT;ARM_REST_RIGHT;LEG_LEFT;LEG_RIGHT
+ANIM_IDLE_1=
+! ANIM_IDLE_1 will not make any transformation
+ANIM_IDLE_2=UPPER_TORSO 0,-1
+
+ANIM_CROUCH=DELAY 1;ROW 3
+ANIM_CROUCH_BODYPARTS=HEAD;UPPER_TORSO;LOWER_TORSO;ARM_FWD_LEFT;ARM_FWD_RIGHT;LEG_CROUCH_LEFT;LEG_CROUCH_RIGHT
+ANIM_CROUCH_1=
+...
+```
+
+### In-detail
+
+```
+ANIM_RUN=DELAY 0.15;ROW 2
+```
+
+Each line defines one property. A property is a field-value pair. In this code, field is ```ANIM_RUN```, and the value is ```DELAY 0.15;ROW 2```
+
+The values are further parsed using ```;``` (semicolon with NO spaces attached) as a separator.
+
+```
+In this example, ANIM_RUN contains two variables:
+
+DELAY = 0.15
+ROW = 2
+```
+
+A value of the field is consisted of zero or more variable-input pairs. Variable and the input are separated with one or more connected spaces.
+
+#### Variables
+
+Variables can have only one of the two types: ```float``` and ```ivec2```. Single integer value ('2' in the ROW) are regarded as a float.
+
+Float and Ivec2 are determined by:
+
+* Ivec2: inputs that are matched by the regex ```-?[0-9]+,-?[0-9]+``` (we call this "ivec2 regex")
+* Float: inputs that are matched by the regex ```-?[0-9]+(\.[0-9]*)?```, but not even partially matched by the ivec2 regex.
+
+Any argument to the body parts takes ivec2, to move the parts accordingly.
+
+#### Just one exception: SPRITESHEET and EXTENSION
+
+SPRITESHEET and EXTENSION property is not parsed as a property, it's just a single string like the original .properties
+
+### Naming convention of properties
+
+If a field is recognised as an animation (in this case ANIM_RUN), the assembler will look for the fields named like ANIM_RUN_1, ANIM_RUN_2, ... , ANIM_RUN_9, ANIM_RUN_10 and beyond.
+
+### Naming convention of files
+
+If the animation specifies a "body part" (in this example LEG_LEFT and LEG_RIGHT), the assembler will look for a file ```sprites/test_leg_left.tga.gz``` and ```sprites/test_leg_right.tga.gz``` respectively.
+
+#### Reserved keywords
+
+|Name|Type|Meaning|
+|---|---|---|
+|SPRITESHEET|property/string|base file name of the images|
+|EXTENSION|property/string|extension of the base file|
+|DELAY|variable: float|delay between frames, in seconds|
+|ROW|vareable: float|which row the animation goes in the spritesheet|
+
+### Notes
+
+* All indices are one-based
+
+## Operation
+
+* Each line describes transformation
+* Transformation are applied sequentially from left to right. In other words, their order matters. Be wary of the clipping that may occur!
+* The Field is an identifier the game code -- sprite assembler -- recognises.
+* The Field of animation's name is the name the game code looks for. Example: ```this.setAnim("ANIM_RUN")```
diff --git a/src/net/torvald/terrarum/tests/ADLParsingTest.kt b/src/net/torvald/terrarum/tests/ADLParsingTest.kt
new file mode 100644
index 000000000..d59189927
--- /dev/null
+++ b/src/net/torvald/terrarum/tests/ADLParsingTest.kt
@@ -0,0 +1,49 @@
+package net.torvald.terrarum.tests
+
+import net.torvald.spriteassembler.ADProperties
+import java.io.StringReader
+
+/**
+ * Created by minjaesong on 2019-01-05.
+ */
+class ADLParsingTest {
+
+    val TEST_STR = """
+        SPRITESHEET=sprites/test
+        EXTENSION=.tga.gz
+
+        ANIM_RUN=DELAY 0.15;ROW 2
+        ANIM_RUN_BODYPARTS=HEAD;UPPER_TORSO;LOWER_TORSO;ARM_FWD_LEFT;ARM_FWD_RIGHT;LEG_LEFT;LEG_RIGHT
+        ANIM_RUN_1=LEG_RIGHT 1,-1;LEG_LEFT -1,0
+        ANIM_RUN_2=ALL 0,-1;LEG_RIGHT 0,1;LEG_LEFT 0,-1
+        ANIM_RUN_3=LEG_RIGHT -1,0;LEG_LEFT 1,-1
+        ANIM_RUN_4=ALL 0,-1;LEG_RIGHT 0,-1;LEG_LEFT 0,1
+
+        ANIM_IDLE=DELAY 2;ROW 1
+        ANIM_IDLE_BODYPARTS=HEAD;UPPER_TORSO;LOWER_TORSO;ARM_REST_LEFT;ARM_REST_RIGHT;LEG_LEFT;LEG_RIGHT
+        ANIM_IDLE_1=
+        ! ANIM_IDLE_1 will not make any transformation
+        ANIM_IDLE_2=UPPER_TORSO 0,-1
+
+        ANIM_CROUCH=DELAY 1;ROW 3
+        ANIM_CROUCH_BODYPARTS=HEAD;UPPER_TORSO;LOWER_TORSO;ARM_FWD_LEFT;ARM_FWD_RIGHT;LEG_CROUCH_LEFT;LEG_CROUCH_RIGHT
+        ANIM_CROUCH_1=
+    """.trimIndent()
+
+    operator fun invoke() {
+        val prop = ADProperties(StringReader(TEST_STR))
+
+        prop.forEach { s, list ->
+            println(s)
+
+            list.forEach {
+                println("\t$it")
+            }
+        }
+    }
+
+}
+
+fun main(args: Array<String>) {
+    ADLParsingTest().invoke()
+}
\ No newline at end of file
diff --git a/src/org/dyn4j/geometry/Vector2.kt b/src/org/dyn4j/geometry/Vector2.kt
index 3b9724322..e1629da4e 100644
--- a/src/org/dyn4j/geometry/Vector2.kt
+++ b/src/org/dyn4j/geometry/Vector2.kt
@@ -57,7 +57,7 @@ import org.dyn4j.Epsilon
  * |a rotate th|Vector2(a).rotate(th)|
  * |a to b     |Vector2(a).to(b)     |
  *
- * @author William Bittle
+ * @author William Bittle and Minjaesong (Torvald)
  * *
  * @version 3.1.11
  * *