adopt handedness conversion scheme from the fabric mod

conversion scheme still converts Minecraft's a right-handed system to Mumble's left-handed system but using a different approach (switching z axis instead of previously swapping z and y axis)

fixes #55

mod/build.gradle

@@ -18,7 +18,7 @@ apply plugin: 'net.minecraftforge.gradle'
 apply plugin: 'idea'
 apply plugin: 'maven-publish'
 
-ext.modversion              = "5.1.0"
+ext.modversion              = "6.0.0"
 ext.mcversion               = "1.18.1"
 ext.forgeversion_dependency = "39"
 ext.forgeversion            = "39.0.0"

mod/src/main/java/zsawyer/mods/mumblelink/mumble/UpdateData.java

@@ -100,65 +100,76 @@ public void set(Minecraft game) {
             // 1 unit = 1 meter
 
             // initialize multipliers
+            // converted to left-handed coordinate system
+            //   (Mumble uses a left-handed, Minecraft uses a right-handed)
+            float fAvatarPositionX = 1;
+            float fAvatarPositionY = 1;
+            float fAvatarPositionZ = -1; // switch to left-handedness
+
+            float fCameraPositionX = 1;
+            float fCameraPositionY = 1;
+            float fCameraPositionZ = -1; // switch to left-handedness
+
             float fAvatarFrontX = 1;
             float fAvatarFrontY = 1;
-            float fAvatarFrontZ = 1;
+            float fAvatarFrontZ = -1; // switch to left-handedness
 
             float fCameraFrontX = 1;
             float fCameraFrontY = 1;
-            float fCameraFrontZ = 1;
+            float fCameraFrontZ = -1; // switch to left-handedness
 
             float fAvatarTopX = 1;
-            float fAvatarTopY = 1; // Y points up
-            float fAvatarTopZ = 1;
+            float fAvatarTopY = 1;
+            float fAvatarTopZ = -1; // switch to left-handedness
 
             float fCameraTopX = 1;
-            float fCameraTopY = 1; // Y points up
-            float fCameraTopZ = 1;
+            float fCameraTopY = 1;
+            float fCameraTopZ = -1; // switch to left-handedness
 
             Vec3 lookDirection = game.player.getLookAngle();
             Vec3 topDirection = getTopVec(game);
 
             // Position of the avatar
             fAvatarPosition = new float[]{
-                    (float) game.player.getPosition(1f).x(),
-                    (float) game.player.getPosition(1f).z(),
-                    (float) game.player.getPosition(1f).y()
+                    (float) game.player.getPosition(1f).x() * fAvatarPositionX,
+                    (float) game.player.getPosition(1f).y() * fAvatarPositionY,
+                    (float) game.player.getPosition(1f).z() * fAvatarPositionZ
             };
 
             // Unit vector pointing out of the avatar's eyes (here Front looks
             // into scene).
             fAvatarFront = new float[]{
                     (float) lookDirection.x * fAvatarFrontX,
-                    (float) lookDirection.z * fAvatarFrontZ,
-                    (float) lookDirection.y * fAvatarFrontY
+                    (float) lookDirection.y * fAvatarFrontY,
+                    (float) lookDirection.z * fAvatarFrontZ
             };
 
             // Unit vector pointing out of the top of the avatar's head (here
             // Top looks straight up).
             fAvatarTop = new float[]{
                     (float) topDirection.x * fAvatarTopX,
-                    (float) topDirection.z * fAvatarTopZ,
-                    (float) topDirection.y * fAvatarTopY
+                    (float) topDirection.y * fAvatarTopY,
+                    (float) topDirection.z * fAvatarTopZ
             };
 
             // TODO: use real camera position, s.a.
+            // Position of the camera
             fCameraPosition = new float[]{
-                    (float) game.player.getPosition(1f).x(),
-                    (float) game.player.getPosition(1f).z(),
-                    (float) game.player.getPosition(1f).y()
+                    (float) game.player.getPosition(1f).x() * fCameraPositionX,
+                    (float) game.player.getPosition(1f).y() * fCameraPositionY,
+                    (float) game.player.getPosition(1f).z() * fCameraPositionZ
             };
 
             fCameraFront = new float[]{
                     (float) lookDirection.x * fCameraFrontX,
-                    (float) lookDirection.z * fCameraFrontZ,
-                    (float) lookDirection.y * fCameraFrontY
+                    (float) lookDirection.y * fCameraFrontY,
+                    (float) lookDirection.z * fCameraFrontZ
             };
 
             fCameraTop = new float[]{
                     (float) topDirection.x * fCameraTopX,
-                    (float) topDirection.z * fCameraTopZ,
-                    (float) topDirection.y * fCameraTopY
+                    (float) topDirection.y * fCameraTopY,
+                    (float) topDirection.z * fCameraTopZ
             };
 
             // Identifier which uniquely identifies a certain player in a