diff --git a/res/graphics/black_body_col_1000_40000_K.png b/res/graphics/colourmap/black_body_col_1000_40000_K.png
similarity index 100%
rename from res/graphics/black_body_col_1000_40000_K.png
rename to res/graphics/colourmap/black_body_col_1000_40000_K.png
diff --git a/res/graphics/black_body_how_to_use.txt b/res/graphics/colourmap/black_body_how_to_use.txt
similarity index 100%
rename from res/graphics/black_body_how_to_use.txt
rename to res/graphics/colourmap/black_body_how_to_use.txt
diff --git a/res/graphics/col12spectrum.png b/res/graphics/colourmap/col12spectrum.png
similarity index 100%
rename from res/graphics/col12spectrum.png
rename to res/graphics/colourmap/col12spectrum.png
diff --git a/res/graphics/col216spectrum.png b/res/graphics/colourmap/col216spectrum.png
similarity index 100%
rename from res/graphics/col216spectrum.png
rename to res/graphics/colourmap/col216spectrum.png
diff --git a/res/graphics/colourkey12.png b/res/graphics/colourmap/colourkey12.png
similarity index 100%
rename from res/graphics/colourkey12.png
rename to res/graphics/colourmap/colourkey12.png
diff --git a/res/graphics/colourkey216.png b/res/graphics/colourmap/colourkey216.png
similarity index 100%
rename from res/graphics/colourkey216.png
rename to res/graphics/colourmap/colourkey216.png
diff --git a/res/graphics/health_bar_colouring_4096.png b/res/graphics/colourmap/health_bar_colouring_4096.png
similarity index 100%
rename from res/graphics/health_bar_colouring_4096.png
rename to res/graphics/colourmap/health_bar_colouring_4096.png
diff --git a/res/graphics/sky_colour.png b/res/graphics/colourmap/sky_colour.png
similarity index 70%
rename from res/graphics/sky_colour.png
rename to res/graphics/colourmap/sky_colour.png
index 57fb26e88..995a57d0b 100644
Binary files a/res/graphics/sky_colour.png and b/res/graphics/colourmap/sky_colour.png differ
diff --git a/src/net/torvald/terrarum/ENVIRON.md b/src/net/torvald/terrarum/ENVIRON.md
new file mode 100644
index 000000000..4feb3e7aa
--- /dev/null
+++ b/src/net/torvald/terrarum/ENVIRON.md
@@ -0,0 +1,15 @@
+## Colour overlay ##
+
+Colour overlay is set to 6 500 K as untouched. The value must be
+
+* Increased when:
+    - Overcast (~ 7 000 K)
+    - Freezing area (~ 7 500 K)
+    
+* Decreased when:
+    - Tropical area (~ 5 500 K)
+    
+    
+## Sunlight ##
+
+Sunlight of the midday must have colour temperature of 5 700 K.
\ No newline at end of file
diff --git a/src/net/torvald/terrarum/Game.kt b/src/net/torvald/terrarum/Game.kt
index 0cdd307f5..80120abd2 100644
--- a/src/net/torvald/terrarum/Game.kt
+++ b/src/net/torvald/terrarum/Game.kt
@@ -94,7 +94,7 @@ constructor() : BasicGameState() {
         shaderBlurV = Shader.makeShader("./res/blurV.vrt", "./res/blur.frg")
 
 
-        GRADIENT_IMAGE = Image("res/graphics/sky_colour.png")
+        GRADIENT_IMAGE = Image("res/graphics/colourmap/sky_colour.png")
         skyBox = Rectangle(0f, 0f, Terrarum.WIDTH.toFloat(), Terrarum.HEIGHT.toFloat())
 
         TilePropCodex()
diff --git a/src/net/torvald/terrarum/gameactors/AVKey.kt b/src/net/torvald/terrarum/gameactors/AVKey.kt
index 681c2070a..49d447f5e 100644
--- a/src/net/torvald/terrarum/gameactors/AVKey.kt
+++ b/src/net/torvald/terrarum/gameactors/AVKey.kt
@@ -20,6 +20,7 @@ object AVKey {
     const val ENCUMBRANCE = "encumbrance"
     const val LUMINOSITY = "luminosity"
     const val PHYSIQUEMULT = "physique$MULT"
+    const val DRAGCOEFF = "dragcoeff"
 
     const val NAME = "name"
 
diff --git a/src/net/torvald/terrarum/gameactors/ActorWithBody.kt b/src/net/torvald/terrarum/gameactors/ActorWithBody.kt
index e8ce61311..6b3903f22 100644
--- a/src/net/torvald/terrarum/gameactors/ActorWithBody.kt
+++ b/src/net/torvald/terrarum/gameactors/ActorWithBody.kt
@@ -35,13 +35,13 @@ open class ActorWithBody constructor() : Actor(), Visible {
      *     veloY += 3.0
      * +3.0 is acceleration. You __accumulate__ acceleration to the velocity.
      */
-    val velocity = ChainedVector2(0.0, 0.0)
+    internal val positioningDelta = Vector2(0.0, 0.0)
     var veloX: Double
-        get() = velocity.x
-        set(value) { velocity.x = value }
+        get() = positioningDelta.x
+        private set(value) { positioningDelta.x = value }
     var veloY: Double
-        get() = velocity.y
-        set(value) { velocity.y = value }
+        get() = positioningDelta.y
+        private set(value) { positioningDelta.y = value }
     @Transient private val VELO_HARD_LIMIT = 10000.0
 
     var grounded = false
@@ -92,14 +92,14 @@ open class ActorWithBody constructor() : Actor(), Visible {
         set(value) {
             if (value < 0)
                 throw IllegalArgumentException("[ActorWithBody] Invalid elasticity value: $value; valid elasticity value is [0, 1].")
-            else if (value > 1) {
-                println("[ActorWithBody] Elasticity were capped to 1.")
+            else if (value >= ELASTICITY_MAX) {
+                println("[ActorWithBody] Elasticity were capped to $ELASTICITY_MAX.")
                 field = ELASTICITY_MAX
             }
             else
                 field = value * ELASTICITY_MAX
         }
-    @Transient private val ELASTICITY_MAX = 0.993
+    @Transient private val ELASTICITY_MAX = 0.993 // No perpetual motion!
     private var density = 1000.0
 
     /**
@@ -119,7 +119,15 @@ open class ActorWithBody constructor() : Actor(), Visible {
     @Transient private val SI_TO_GAME_VEL = METER / Terrarum.TARGET_FPS
 
     @Transient private var gravitation: Vector2 = map.gravitation
-    @Transient private val DRAG_COEFF = 1.0
+    @Transient val DRAG_COEFF_DEFAULT = 1.2
+    /** Drag coeffisient. Parachutes have much higher value than bare body (1.2) */
+    private var DRAG_COEFF: Double
+        get() = actorValue.getAsDouble(AVKey.DRAGCOEFF) ?: DRAG_COEFF_DEFAULT
+        set(value) {
+            if (value < 0)
+                throw IllegalArgumentException("[ActorWithBody] drag coefficient cannot be negative.")
+            actorValue[AVKey.DRAGCOEFF] = value
+        }
 
     @Transient private val CONTACT_AREA_TOP = 0
     @Transient private val CONTACT_AREA_RIGHT = 1
@@ -158,7 +166,7 @@ open class ActorWithBody constructor() : Actor(), Visible {
     @Transient private var posAdjustX = 0
     @Transient private var posAdjustY = 0
 
-    @Transient private val BASE_FRICTION = 0.3
+    @Transient internal val BASE_FRICTION = 0.3
 
     @Transient val KINEMATIC = 1
     @Transient val DYNAMIC = 2
@@ -168,6 +176,10 @@ open class ActorWithBody constructor() : Actor(), Visible {
     private val CCD_THRE = 1.0
     private val CCD_TICK = 0.125
 
+    val movementDelta = Vector2(0.0, 0.0)
+    val externalDelta = Vector2(0.0, 0.0)
+    private val gravityDelta = Vector2(0.0 , 0.0)
+
     init {
 
     }
@@ -230,9 +242,6 @@ open class ActorWithBody constructor() : Actor(), Visible {
                 baseSpriteWidth = sprite!!.width
             }
 
-            // copy gravitational constant from the map the actor is in
-            gravitation = map.gravitation
-
             /**
              * Actual physics thing (altering velocity) starts from here
              */
@@ -242,6 +251,8 @@ open class ActorWithBody constructor() : Actor(), Visible {
                 //applyBuoyancy()
             }
 
+            positioningDelta.set(movementDelta + externalDelta + gravityDelta)
+
             // hard limit velocity
             if (veloX > VELO_HARD_LIMIT) veloX = VELO_HARD_LIMIT
             if (veloY > VELO_HARD_LIMIT) veloY = VELO_HARD_LIMIT
@@ -290,18 +301,19 @@ open class ActorWithBody constructor() : Actor(), Visible {
              * W = mass * G (9.8 [m/s^2])
              */
             val W: Vector2 = gravitation * mass
+            /**
+             * Area
+             */
+            val A: Double = scale * scale
             /**
              * Drag of atmosphere
              * D = Cd (drag coefficient) * 0.5 * rho (density) * V^2 (velocity) * A (area)
              */
-            // TODO replace 1.292 with fluid tile density
-            val A: Double = scale * scale
-            val D: Vector2 = velocity.copy().toVector() * DRAG_COEFF * 0.5 * 1.292 * A
+            val D: Vector2 = (gravityDelta + movementDelta) * DRAG_COEFF * 0.5 * A * tileDensityFluid.toDouble()
 
-            //veloY += (W - D) / mass * SI_TO_GAME_ACC
             val V: Vector2 = (W - D) / mass * SI_TO_GAME_ACC
-            veloX += V.x
-            veloY += V.y
+
+            gravityDelta += V
         }
     }
 
@@ -335,12 +347,14 @@ open class ActorWithBody constructor() : Actor(), Visible {
                 if (isColliding(CONTACT_AREA_BOTTOM)) { // the ground has dug into the body
                     adjustHitBottom()
                     veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY()
+                    gravityDelta.zero()
+                    hitAndReflectY()
                     grounded = true
                 }
                 else if (isColliding(CONTACT_AREA_BOTTOM, 0, 1)) { // the actor is standing ON the ground
                     veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY()
+                    gravityDelta.zero()
+                    hitAndReflectY()
                     grounded = true
                 }
                 else { // the actor is not grounded at all
@@ -352,11 +366,11 @@ open class ActorWithBody constructor() : Actor(), Visible {
                 if (isColliding(CONTACT_AREA_TOP)) { // the ceiling has dug into the body
                     adjustHitTop()
                     veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY()
+                    hitAndReflectY()
                 }
                 else if (isColliding(CONTACT_AREA_TOP, 0, -1)) { // the actor is touching the ceiling
                     veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY() // reflect on ceiling, for reversed gravity
+                    hitAndReflectY() // reflect on ceiling, for reversed gravity
                 }
                 else { // the actor is not grounded at all
                 }
@@ -409,12 +423,12 @@ open class ActorWithBody constructor() : Actor(), Visible {
                     // the actor is embedded to the wall
                     adjustHitRight()
                     veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
+                    hitAndReflectX()
                 }
                 else if (isColliding(CONTACT_AREA_RIGHT, 2, 0) && !isColliding(CONTACT_AREA_LEFT, 0, 0)) { // offset by +1, to fix directional quarks
                     // the actor is touching the wall
                     veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
+                    hitAndReflectX()
                 }
                 else {
                 }
@@ -425,12 +439,12 @@ open class ActorWithBody constructor() : Actor(), Visible {
                     // the actor is embedded to the wall
                     adjustHitLeft()
                     veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
+                    hitAndReflectX()
                 }
                 else if (isColliding(CONTACT_AREA_LEFT, -1, 0) && !isColliding(CONTACT_AREA_RIGHT, 1, 0)) {
                     // the actor is touching the wall
                     veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
+                    hitAndReflectX()
                 }
                 else {
                 }
@@ -503,14 +517,10 @@ open class ActorWithBody constructor() : Actor(), Visible {
         if (!isNoCollideWorld) {
             // axis Y
             if (veloY >= 0) { // check downward
-                if (isColliding(CONTACT_AREA_BOTTOM)) { // the ground has dug into the body
-                    veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY()
-                    grounded = true
-                }
-                else if (isColliding(CONTACT_AREA_BOTTOM, 0, 1)) { // the actor is standing ON the ground
-                    veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY()
+                if (isColliding(CONTACT_AREA_BOTTOM) || isColliding(CONTACT_AREA_BOTTOM, 0, 1)) {
+                    // the actor is hitting the ground
+                    //veloY = 0.0 // reset veloY, simulating normal force
+                    hitAndReflectY()
                     grounded = true
                 }
                 else { // the actor is not grounded at all
@@ -519,43 +529,32 @@ open class ActorWithBody constructor() : Actor(), Visible {
             }
             else if (veloY < 0) { // check upward
                 grounded = false
-                if (isColliding(CONTACT_AREA_TOP)) { // the ceiling has dug into the body
-                    veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY()
-                }
-                else if (isColliding(CONTACT_AREA_TOP, 0, -1)) { // the actor is touching the ceiling
-                    veloY = 0.0 // reset veloY, simulating normal force
-                    elasticReflectY() // reflect on ceiling, for reversed gravity
+                if (isColliding(CONTACT_AREA_TOP) || isColliding(CONTACT_AREA_TOP, 0, -1)) {
+                    // the actor is hitting the ceiling
+                    //veloY = 0.0 // reset veloY, simulating normal force
+                    hitAndReflectY()
                 }
                 else { // the actor is not grounded at all
                 }
             }
             // axis X
             if (veloX >= 0.5) { // check right
-                if (isColliding(CONTACT_AREA_RIGHT) && !isColliding(CONTACT_AREA_LEFT)) {
-                    // the actor is embedded to the wall
-                    veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
-                }
-                else if (isColliding(CONTACT_AREA_RIGHT, 2, 0) && !isColliding(CONTACT_AREA_LEFT, 0, 0)) { // offset by +1, to fix directional quarks
-                    // the actor is touching the wall
-                    veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
+                if ((isColliding(CONTACT_AREA_RIGHT) && !isColliding(CONTACT_AREA_LEFT))
+                || (isColliding(CONTACT_AREA_RIGHT, 1, 0) && !isColliding(CONTACT_AREA_LEFT, 0, -1))) {
+                    // the actor is hitting the right wall
+                    //veloX = 0.0 // reset veloX, simulating normal force
+                    hitAndReflectX()
                 }
                 else {
                 }
             }
             else if (veloX <= -0.5) { // check left
                 // System.out.println("collidingleft");
-                if (isColliding(CONTACT_AREA_LEFT) && !isColliding(CONTACT_AREA_RIGHT)) {
-                    // the actor is embedded to the wall
-                    veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
-                }
-                else if (isColliding(CONTACT_AREA_LEFT, -1, 0) && !isColliding(CONTACT_AREA_RIGHT, 1, 0)) {
-                    // the actor is touching the wall
-                    veloX = 0.0 // reset veloX, simulating normal force
-                    elasticReflectX()
+                if ((isColliding(CONTACT_AREA_LEFT) && !isColliding(CONTACT_AREA_RIGHT))
+                || (isColliding(CONTACT_AREA_LEFT, -1, 0) && !isColliding(CONTACT_AREA_RIGHT, 1, 0))) {
+                    // the actor is hitting the left wall
+                    //veloX = 0.0 // reset veloX, simulating normal force
+                    hitAndReflectX()
                 }
                 else {
                 }
@@ -565,17 +564,22 @@ open class ActorWithBody constructor() : Actor(), Visible {
         }
     }
 
-    private fun elasticReflectX() {
-        if (veloX != 0.0 && (veloX * elasticity).abs() > 0.5) {
+    private fun hitAndReflectX() {
+        if ((veloX * elasticity).abs() > SLEEP_THRE) {
             veloX = -veloX * elasticity
-
+        }
+        else {
+            veloX = 0.0
         }
     }
 
-    private fun elasticReflectY() {
-        if (veloY != 0.0 && (veloY * elasticity).abs() > 0.5) {
+    private fun hitAndReflectY() {
+        if ((veloY * elasticity).abs() > SLEEP_THRE) {
             veloY = -veloY * elasticity
         }
+        else {
+            veloY = 0.0
+        }
     }
 
     private fun isColliding(side: Int, tx: Int = 0, ty: Int = 0): Boolean = getContactingArea(side, tx, ty) > 1
@@ -689,11 +693,11 @@ open class ActorWithBody constructor() : Actor(), Visible {
      * Get highest friction value from feet tiles.
      * @return
      */
-    private val tileFriction: Int
+    internal val tileFriction: Int
         get() {
             var friction = 0
 
-            //get highest friction
+            // take highest value
             val tilePosXStart = (hitbox.posX / TSIZE).roundToInt()
             val tilePosXEnd = (hitbox.hitboxEnd.x / TSIZE).roundToInt()
             val tilePosY = (hitbox.pointedY.plus(1) / TSIZE).roundToInt()
@@ -708,6 +712,30 @@ open class ActorWithBody constructor() : Actor(), Visible {
         }
     fun Int.tileFrictionToMult() = this / 16.0
 
+    /**
+     * Get highest tile density from occupying tiles, fluid only
+     */
+    private val tileDensityFluid: Int
+        get() {
+            var density = 0
+
+            // take highest value
+            val tilePosXStart = (hitbox.posX / TSIZE).roundToInt()
+            val tilePosXEnd = (hitbox.hitboxEnd.x / TSIZE).roundToInt()
+            val tilePosYStart = (hitbox.posY / TSIZE).roundToInt()
+            val tilePosYEnd = (hitbox.hitboxEnd.y / TSIZE).roundToInt()
+            for (y in tilePosXStart..tilePosYEnd) {
+                for (x in tilePosXStart..tilePosXEnd) {
+                    val tile = map.getTileFromTerrain(x, y)
+                    val prop = TilePropCodex.getProp(tile)
+
+                    if (prop.isFluid && prop.density > density)
+                        density = prop.density
+                }
+            }
+            return density
+        }
+
     /**
      * Get highest density (specific gravity) value from tiles that the body occupies.
      * @return
diff --git a/src/net/torvald/terrarum/gameactors/Player.kt b/src/net/torvald/terrarum/gameactors/Player.kt
index 73da15585..19e0e916e 100644
--- a/src/net/torvald/terrarum/gameactors/Player.kt
+++ b/src/net/torvald/terrarum/gameactors/Player.kt
@@ -6,6 +6,8 @@ import net.torvald.terrarum.gamecontroller.KeyMap
 import net.torvald.terrarum.mapdrawer.MapDrawer
 import net.torvald.terrarum.Terrarum
 import net.torvald.spriteanimation.SpriteAnimation
+import org.dyn4j.geometry.ChainedVector2
+import org.dyn4j.geometry.Vector2
 import org.lwjgl.input.Controller
 import org.lwjgl.input.Controllers
 import org.newdawn.slick.GameContainer
@@ -33,8 +35,10 @@ class Player : ActorWithBody, Controllable, Pocketed, Factionable, Luminous, Lan
 
     var vehicleRiding: Controllable? = null
 
+    /** how long the jump button has down, in frames */
     internal var jumpCounter = 0
-    internal var walkPowerCounter = 0
+    /** how long the walk button has down, in frames */
+    internal var walkCounter = 0
     @Transient private val MAX_JUMP_LENGTH = 17 // use 17; in internal frames
 
     private var readonly_totalX = 0.0
@@ -115,30 +119,38 @@ class Player : ActorWithBody, Controllable, Pocketed, Factionable, Luminous, Lan
      * @param absAxisVal (set AXIS_POSMAX if keyboard controlled)
      */
     private fun walkHorizontal(left: Boolean, absAxisVal: Float) {
-        readonly_totalX = veloX +
-                          actorValue.getAsDouble(AVKey.ACCEL)!! *
+        readonly_totalX = //veloX +
+                          /*actorValue.getAsDouble(AVKey.ACCEL)!! *
                           actorValue.getAsDouble(AVKey.ACCELMULT)!! *
                           Math.sqrt(scale) *
                           applyAccelRealism(walkPowerCounter) *
                           (if (left) -1 else 1).toFloat() *
-                          absAxisVal
+                          absAxisVal*/
+                actorValue.getAsDouble(AVKey.ACCEL)!! *
+                actorValue.getAsDouble(AVKey.ACCELMULT)!! *
+                Math.sqrt(scale) *
+                applyVelo(walkCounter) *
+                (if (left) -1 else 1).toFloat() *
+                absAxisVal
 
-        veloX = readonly_totalX
+        // veloX = readonly_totalX
+        movementDelta += Vector2(readonly_totalX, 0.0)
 
-        if (walkPowerCounter < WALK_FRAMES_TO_MAX_ACCEL) {
-            walkPowerCounter += 1
-        }
+        walkCounter += 1
 
         // Clamp veloX
-        veloX = absClamp(veloX, actorValue.getAsDouble(AVKey.SPEED)!!
-                        * actorValue.getAsDouble(AVKey.SPEEDMULT)!!
-                        * Math.sqrt(scale))
+        movementDelta.x = absClamp(movementDelta.x,
+                actorValue.getAsDouble(AVKey.SPEED)!!
+                * actorValue.getAsDouble(AVKey.SPEEDMULT)!!
+                * Math.sqrt(scale))
 
         // Heading flag
         if (left)
             walkHeading = LEFT
         else
             walkHeading = RIGHT
+
+        println("$walkCounter: ${movementDelta.x}")
     }
 
     /**
@@ -148,51 +160,35 @@ class Player : ActorWithBody, Controllable, Pocketed, Factionable, Luminous, Lan
      * @param absAxisVal (set AXIS_POSMAX if keyboard controlled)
      */
     private fun walkVertical(up: Boolean, absAxisVal: Float) {
-        readonly_totalY = veloY +
+        readonly_totalY =
                 actorValue.getAsDouble(AVKey.ACCEL)!! *
-                        actorValue.getAsDouble(AVKey.ACCELMULT)!! *
-                        Math.sqrt(scale) *
-                        applyAccelRealism(walkPowerCounter) *
-                        (if (up) -1 else 1).toFloat() *
-                        absAxisVal
+                actorValue.getAsDouble(AVKey.ACCELMULT)!! *
+                Math.sqrt(scale) *
+                applyVelo(walkCounter) *
+                (if (up) -1 else 1).toFloat() *
+                absAxisVal
 
-        veloY = readonly_totalY
+        movementDelta.set(Vector2(0.0, readonly_totalY))
 
-        if (walkPowerCounter < WALK_FRAMES_TO_MAX_ACCEL) {
-            walkPowerCounter += 1
-        }
+        if (walkCounter <= WALK_FRAMES_TO_MAX_ACCEL) walkCounter += 1
 
         // Clamp veloX
-        veloY = absClamp(veloY, actorValue.getAsDouble(AVKey.SPEED)!!
-                        * actorValue.getAsDouble(AVKey.SPEEDMULT)!!
-                        * Math.sqrt(scale))
+        movementDelta.y = absClamp(movementDelta.y,
+                actorValue.getAsDouble(AVKey.SPEED)!! *
+                actorValue.getAsDouble(AVKey.SPEEDMULT)!! *
+                Math.sqrt(scale))
     }
 
-    /**
-     * For realistic accelerating while walking.
+    private fun applyAccel(x: Int): Double {
+        return if (x < WALK_FRAMES_TO_MAX_ACCEL)
+            Math.sin(Math.PI * x / WALK_FRAMES_TO_MAX_ACCEL)
+        else 0.0
+    }
 
-     * Naïve 'veloX += 3' is actually like:
-
-     * a
-     * |      ------------
-     * |
-     * |
-     * 0+------············  t
-
-     * which is unrealistic, so this method tries to introduce some realism by doing:
-
-     * a
-     * |           ------------
-     * |        ---
-     * |       -
-     * |    ---
-     * 0+----··················· t
-
-
-     * @param x
-     */
-    private fun applyAccelRealism(x: Int): Double {
-        return 0.5 + 0.5 * -Math.cos(10 * x / (WALK_FRAMES_TO_MAX_ACCEL * Math.PI))
+    private fun applyVelo(x: Int): Double {
+        return if (x < WALK_FRAMES_TO_MAX_ACCEL)
+            0.5 - 0.5 * Math.cos(Math.PI * x / WALK_FRAMES_TO_MAX_ACCEL)
+        else 1.0
     }
 
     // stops; let the friction kick in by doing nothing to the velocity here
@@ -217,7 +213,8 @@ class Player : ActorWithBody, Controllable, Pocketed, Factionable, Luminous, Lan
 
         //veloX = 0f
 
-        walkPowerCounter = 0
+        walkCounter = 0
+        movementDelta.zero()
     }
 
     // stops; let the friction kick in by doing nothing to the velocity here
@@ -243,7 +240,36 @@ class Player : ActorWithBody, Controllable, Pocketed, Factionable, Luminous, Lan
 
         ///veloY = 0f
 
-        walkPowerCounter = 0
+        walkCounter = 0
+        movementDelta.zero()
+    }
+
+    /**
+     * See ./work_files/Jump\ power\ by\ pressing\ time.gcx
+     */
+    private fun jump() {
+        if (jumping) {
+            val len = MAX_JUMP_LENGTH.toFloat()
+            val pwr = actorValue.getAsDouble(AVKey.JUMPPOWER)!! * (actorValue.getAsDouble(AVKey.JUMPPOWERMULT) ?: 1.0)
+
+            // increment jump counter
+            if (jumpCounter < len) jumpCounter += 1
+
+            // linear time mode
+            val init = (len + 1) / 2.0
+            var timedJumpCharge = init - init / len * jumpCounter
+            if (timedJumpCharge < 0) timedJumpCharge = 0.0
+
+            val jumpAcc = pwr * timedJumpCharge * JUMP_ACCELERATION_MOD * Math.sqrt(scale)
+
+            movementDelta.y -= jumpAcc
+        }
+
+        // for mob ai:
+        //super.setVeloY(veloY
+        //        -
+        //        pwr * Math.sqrt(scale)
+        //);
     }
 
     private fun updateMovementControl() {
@@ -391,34 +417,6 @@ class Player : ActorWithBody, Controllable, Pocketed, Factionable, Luminous, Lan
 
     }
 
-    /**
-     * See ./work_files/Jump\ power\ by\ pressing\ time.gcx
-     */
-    private fun jump() {
-        if (jumping) {
-            val len = MAX_JUMP_LENGTH.toFloat()
-            val pwr = actorValue.getAsDouble(AVKey.JUMPPOWER)!! * (actorValue.getAsDouble(AVKey.JUMPPOWERMULT) ?: 1.0)
-
-            // increment jump counter
-            if (jumpCounter < len) jumpCounter += 1
-
-            // linear time mode
-            val init = (len + 1) / 2.0
-            var timedJumpCharge = init - init / len * jumpCounter
-            if (timedJumpCharge < 0) timedJumpCharge = 0.0
-
-            val jumpAcc = pwr * timedJumpCharge * JUMP_ACCELERATION_MOD * Math.sqrt(scale)
-
-            veloY -= jumpAcc
-        }
-
-        // for mob ai:
-        //super.setVeloY(veloY
-        //        -
-        //        pwr * Math.sqrt(scale)
-        //);
-    }
-
     private fun isFuncDown(input: Input, fn: EnumKeyFunc): Boolean {
         return input.isKeyDown(KeyMap.getKeyCode(fn))
     }
diff --git a/src/net/torvald/terrarum/gameactors/physicssolver/CollisionSolver.kt b/src/net/torvald/terrarum/gameactors/physicssolver/CollisionSolver.kt
index c5baccbba..fa0002e62 100644
--- a/src/net/torvald/terrarum/gameactors/physicssolver/CollisionSolver.kt
+++ b/src/net/torvald/terrarum/gameactors/physicssolver/CollisionSolver.kt
@@ -127,10 +127,10 @@ object CollisionSolver {
                 val vy_1 = (uy_2 * (m1 - m2) + 2 * m2 * uy_2) / (m1 + m2)
                 val vy_2 = (uy_2 * (m2 - m1) + 2 * m1 * uy_1) / (m1 + m2)
 
-                a.veloX = vx_1
+                /*a.veloX = vx_1
                 a.veloY = vy_1
                 b.veloX = vx_2
-                b.veloY = vy_2
+                b.veloY = vy_2*/
             }
         }
     }
diff --git a/src/net/torvald/terrarum/gamemap/GameMap.kt b/src/net/torvald/terrarum/gamemap/GameMap.kt
index bca168cd6..236c439b2 100644
--- a/src/net/torvald/terrarum/gamemap/GameMap.kt
+++ b/src/net/torvald/terrarum/gamemap/GameMap.kt
@@ -32,7 +32,7 @@ constructor(//properties
 
     //public World physWorld = new World( new Vec2(0, -TerrarumMain.game.gravitationalAccel) );
     //physics
-    /** \[m / s^2\] */
+    /** Meter per second squared. Currently only the downward gravity is supported. No reverse gravity :p */
     var gravitation: Vector2 = Vector2(0.0, 9.8)
     /** RGB in Integer */
     var globalLight: Int = 0
diff --git a/src/net/torvald/terrarum/mapdrawer/LightmapRenderer.kt b/src/net/torvald/terrarum/mapdrawer/LightmapRenderer.kt
index a64475215..972b65a3d 100644
--- a/src/net/torvald/terrarum/mapdrawer/LightmapRenderer.kt
+++ b/src/net/torvald/terrarum/mapdrawer/LightmapRenderer.kt
@@ -229,8 +229,7 @@ object LightmapRenderer {
         }
         // luminous tile on top of air
         else if (thisWall == AIR && thisTileLuminosity.toInt() > 0) {
-            val darkenSunlight = darkenColoured(sunLight, thisTileOpacity)
-            lightLevelThis = maximiseRGB(darkenSunlight, thisTileLuminosity) // maximise to not exceed 1.0 with normal (<= 1.0) light
+            lightLevelThis = maximiseRGB(sunLight, thisTileLuminosity) // maximise to not exceed 1.0 with normal (<= 1.0) light
         }
         // opaque wall and luminous tile
         else if (thisWall != AIR && thisTileLuminosity.toInt() > 0) {
diff --git a/src/net/torvald/terrarum/mapdrawer/MapDrawer.kt b/src/net/torvald/terrarum/mapdrawer/MapDrawer.kt
index 071950cef..96ef3cae6 100644
--- a/src/net/torvald/terrarum/mapdrawer/MapDrawer.kt
+++ b/src/net/torvald/terrarum/mapdrawer/MapDrawer.kt
@@ -13,12 +13,12 @@ import org.newdawn.slick.*
 object MapDrawer {
     const val TILE_SIZE = 16
 
-    private var envOverlayColourmap: Image = Image("./res/graphics/black_body_col_1000_40000_K.png")
+    private var envOverlayColourmap: Image = Image("./res/graphics/colourmap/black_body_col_1000_40000_K.png")
 
     private val ENV_COLTEMP_LOWEST = 5500
     private val ENV_COLTEMP_HIGHEST = 7500
 
-    val ENV_COLTEMP_NOON = 6500
+    val ENV_COLTEMP_NOON = 6500 // 6500 == sRGB White == untouched!
 
     private var colTemp: Int = 0
 
diff --git a/src/org/dyn4j/geometry/ChainedVector2.kt b/src/org/dyn4j/geometry/ChainedVector2.kt
index 4957e64ac..550d41ba3 100644
--- a/src/org/dyn4j/geometry/ChainedVector2.kt
+++ b/src/org/dyn4j/geometry/ChainedVector2.kt
@@ -378,7 +378,7 @@ class ChainedVector2 {
      * *
      * @return [ChainedVector2] this vector
      */
-    operator fun plus(vector: ChainedVector2): ChainedVector2 {
+    fun plus(vector: ChainedVector2): ChainedVector2 {
         this.x += vector.x
         this.y += vector.y
         return this
@@ -428,7 +428,7 @@ class ChainedVector2 {
      * *
      * @return [ChainedVector2] this vector
      */
-    operator fun minus(vector: ChainedVector2): ChainedVector2 {
+    fun minus(vector: ChainedVector2): ChainedVector2 {
         this.x -= vector.x
         this.y -= vector.y
         return this
@@ -500,7 +500,7 @@ class ChainedVector2 {
      * *
      * @return [ChainedVector2] this vector
      */
-    operator fun times(scalar: Double): ChainedVector2 {
+    fun times(scalar: Double): ChainedVector2 {
         this.x *= scalar
         this.y *= scalar
         return this
@@ -512,7 +512,7 @@ class ChainedVector2 {
      * *
      * @return [ChainedVector2] this vector
      */
-    operator fun div(scalar: Double): ChainedVector2 {
+    fun div(scalar: Double): ChainedVector2 {
         this.x /= scalar
         this.y /= scalar
         return this
@@ -525,7 +525,7 @@ class ChainedVector2 {
      * *
      * @return [ChainedVector2]
      */
-    infix fun product(scalar: Double): ChainedVector2 {
+    fun product(scalar: Double): ChainedVector2 {
         return ChainedVector2(this.x * scalar, this.y * scalar)
     }
 
@@ -536,7 +536,7 @@ class ChainedVector2 {
      * *
      * @return double
      */
-    infix fun dot(vector: ChainedVector2): Double {
+    fun dot(vector: ChainedVector2): Double {
         return this.x * vector.x + this.y * vector.y
     }
 
@@ -559,7 +559,7 @@ class ChainedVector2 {
      * *
      * @return double
      */
-    infix fun cross(vector: ChainedVector2): Double {
+    fun cross(vector: ChainedVector2): Double {
         return this.x * vector.y - this.y * vector.x
     }
 
@@ -581,7 +581,7 @@ class ChainedVector2 {
      * *
      * @return [ChainedVector2]
      */
-    infix fun cross(z: Double): ChainedVector2 {
+    fun cross(z: Double): ChainedVector2 {
         return ChainedVector2(-1.0 * this.y * z, this.x * z)
     }
 
@@ -628,7 +628,7 @@ class ChainedVector2 {
      * Negates this [ChainedVector2].
      * @return [ChainedVector2] this vector
      */
-    operator fun not() = negate()
+    fun not() = negate()
 
     /**
      * Negates this [ChainedVector2].
@@ -663,7 +663,7 @@ class ChainedVector2 {
      * *
      * @return [ChainedVector2] this vector
      */
-    infix fun rotate(theta: Double): ChainedVector2 {
+    fun rotate(theta: Double): ChainedVector2 {
         val cos = Math.cos(theta)
         val sin = Math.sin(theta)
         val x = this.x
diff --git a/work_files/graphics/colourmap/.gitattributes b/work_files/graphics/colourmap/.gitattributes
new file mode 100644
index 000000000..ca82ef549
--- /dev/null
+++ b/work_files/graphics/colourmap/.gitattributes
@@ -0,0 +1 @@
+*.{psd,tga,ogg} filter=lfs diff=lfs merge=lfs -text
\ No newline at end of file