X-Git-Url: http://www2.svjatoslav.eu/gitweb/?p=sixth-3d.git;a=blobdiff_plain;f=src%2Fmain%2Fjava%2Feu%2Fsvjatoslav%2Fsixth%2Fe3d%2Fgui%2FAvatar.java;h=6e4c5ec6daa039e5fc1a7d8f423ea4747dc95367;hp=4234593ae5ae1f78c830cf3263a543842a4eb800;hb=2e7e46514dd35006e9dde07b1959540078292691;hpb=58faaac88fe1a65fe42a68979d4e4d8f3765d878

diff --git a/src/main/java/eu/svjatoslav/sixth/e3d/gui/Avatar.java b/src/main/java/eu/svjatoslav/sixth/e3d/gui/Avatar.java
index 4234593..6e4c5ec 100755
--- a/src/main/java/eu/svjatoslav/sixth/e3d/gui/Avatar.java
+++ b/src/main/java/eu/svjatoslav/sixth/e3d/gui/Avatar.java
@@ -11,6 +11,9 @@ package eu.svjatoslav.sixth.e3d.gui;
 
 import eu.svjatoslav.sixth.e3d.geometry.Point3D;
 
+import static java.lang.Math.cos;
+import static java.lang.Math.sin;
+
 public class Avatar implements ViewUpdateListener {
 
     public static final double SPEED_LIMIT = 30;
@@ -23,7 +26,7 @@ public class Avatar implements ViewUpdateListener {
      * are updated within the world, avatar orientation relative to the world is
      * taken into account.
      */
-    private final Point3D movementDirection = new Point3D();
+    private final Point3D movementVector = new Point3D();
     public double avatarAcceleration = 0.1;
     /**
      * Avatar location within the 3D world.
@@ -41,6 +44,11 @@ public class Avatar implements ViewUpdateListener {
      */
     private double orientationYZ;
 
+    /**
+     * Determines amount of friction user experiences every millisecond while moving around in space.
+     */
+    private static final double MILLISECOND_FRICTION = 1.005;
+
     public Avatar() {
     }
 
@@ -62,27 +70,27 @@ public class Avatar implements ViewUpdateListener {
     }
 
     @Override
-    public boolean beforeViewUpdate(final ViewContext viewContext,
-                                    final int millisecondsSinceLastFrame) {
+    public boolean beforeViewUpdate(final ViewContext viewContext, final int millisecondsSinceLastFrame) {
 
         final Point3D locationBeforeUpdate = new Point3D(location);
-        updateLocation(millisecondsSinceLastFrame);
-
-        final double distanceMoved = location
-                .getDistanceTo(locationBeforeUpdate);
+        translateAvatarLocation(millisecondsSinceLastFrame);
+        applyFrictionToUserMovement(millisecondsSinceLastFrame);
+        return isFrameRepaintNeeded(locationBeforeUpdate);
+    }
 
+    private boolean isFrameRepaintNeeded(Point3D locationBeforeUpdate) {
+        final double distanceMoved = location.getDistanceTo(locationBeforeUpdate);
         return distanceMoved > 0.03;
-
     }
 
     public void enforceSpeedLimit() {
-        final double currentSpeed = movementDirection
+        final double currentSpeed = movementVector
                 .getDistanceTo(Point3D.ZERO);
 
         if (currentSpeed <= SPEED_LIMIT)
             return;
 
-        movementDirection.scaleDown(currentSpeed / SPEED_LIMIT);
+        movementVector.scaleDown(currentSpeed / SPEED_LIMIT);
     }
 
     public double getAngleXZ() {
@@ -109,49 +117,48 @@ public class Avatar implements ViewUpdateListener {
         this.location = location;
     }
 
-    public Point3D getMovementDirection() {
-        return movementDirection;
+    public Point3D getMovementVector() {
+        return movementVector;
     }
 
     public double getMovementSpeed() {
-        return movementDirection.getDistanceTo(Point3D.ZERO);
+        return movementVector.getDistanceTo(Point3D.ZERO);
+    }
+
+    private void applyFrictionToUserMovement(int millisecondsPassedSinceLastFrame) {
+        for (int i = 0; i < millisecondsPassedSinceLastFrame; i++)
+            applyMillisecondFrictionToUserMovementVector();
+    }
+
+    private void applyMillisecondFrictionToUserMovementVector() {
+        getMovementVector().x /= MILLISECOND_FRICTION;
+        getMovementVector().y /= MILLISECOND_FRICTION;
+        getMovementVector().z /= MILLISECOND_FRICTION;
     }
 
     /**
-     * Update camera location based on current speed
+     * Translate coordinates based on avatar movement vector and avatar orientation in the world.
+     *
+     * @param millisecondsPassedSinceLastFrame We want avatar movement to be independent of framerate.
+     *                                         Therefore we take frame rendering time into account when translating
+     *                                         avatar between consecutive frames.
      */
-    public void updateLocation(final int millisecondsPassedSinceLastFrame) {
-
-        // translate user coordinates based on avatar movement speed, and avatar
-        // orientation in the world
-        {
-            location.x -= (float) Math.sin(getAngleXZ())
-                    * getMovementDirection().z * SPEED_MULTIPLIER
-                    * millisecondsPassedSinceLastFrame;
-            location.z += (float) Math.cos(getAngleXZ())
-                    * getMovementDirection().z * SPEED_MULTIPLIER
-                    * millisecondsPassedSinceLastFrame;
-
-            location.x += (float) Math.cos(getAngleXZ())
-                    * getMovementDirection().x * SPEED_MULTIPLIER
-                    * millisecondsPassedSinceLastFrame;
-            location.z += (float) Math.sin(getAngleXZ())
-                    * getMovementDirection().x * SPEED_MULTIPLIER
-                    * millisecondsPassedSinceLastFrame;
-
-            location.y += getMovementDirection().y * SPEED_MULTIPLIER
-                    * millisecondsPassedSinceLastFrame;
-        }
-
-        final double millisecondFriction = 1.005;
-        // apply friction to progressively slow movement
-        for (int i = 0; i < millisecondsPassedSinceLastFrame; i++) {
-            getMovementDirection().x = getMovementDirection().x
-                    / millisecondFriction;
-            getMovementDirection().y = getMovementDirection().y
-                    / millisecondFriction;
-            getMovementDirection().z = getMovementDirection().z
-                    / millisecondFriction;
-        }
+    private void translateAvatarLocation(int millisecondsPassedSinceLastFrame) {
+        location.x -= (float) sin(getAngleXZ())
+                * getMovementVector().z * SPEED_MULTIPLIER
+                * millisecondsPassedSinceLastFrame;
+        location.z += (float) cos(getAngleXZ())
+                * getMovementVector().z * SPEED_MULTIPLIER
+                * millisecondsPassedSinceLastFrame;
+
+        location.x += (float) cos(getAngleXZ())
+                * getMovementVector().x * SPEED_MULTIPLIER
+                * millisecondsPassedSinceLastFrame;
+        location.z += (float) sin(getAngleXZ())
+                * getMovementVector().x * SPEED_MULTIPLIER
+                * millisecondsPassedSinceLastFrame;
+
+        location.y += getMovementVector().y * SPEED_MULTIPLIER
+                * millisecondsPassedSinceLastFrame;
     }
 }