NetHandlerPlayClient.java

    /**
     * Handles changes in player positioning and rotation such as when travelling to a new dimension, (re)spawning,
     * mounting horses etc. Seems to immediately reply to the server with the clients post-processing perspective on the
     * player positioning
     */
    public void handlePlayerPosLook(S08PacketPlayerPosLook packetIn)
    {
        PacketThreadUtil.checkThreadAndEnqueue(packetIn, this, this.gameController);
        EntityPlayer entityplayer = this.gameController.thePlayer;
        double d0 = packetIn.getX();
        double d1 = packetIn.getY();
        double d2 = packetIn.getZ();
        float f = packetIn.getYaw();
        float f1 = packetIn.getPitch();

        if (packetIn.func_179834_f().contains(S08PacketPlayerPosLook.EnumFlags.X))
        {
            d0 += entityplayer.posX;
        }
        else
        {
            entityplayer.motionX = 0.0D;
        }

        if (packetIn.func_179834_f().contains(S08PacketPlayerPosLook.EnumFlags.Y))
        {
            d1 += entityplayer.posY;
        }
        else
        {
            entityplayer.motionY = 0.0D;
        }

        if (packetIn.func_179834_f().contains(S08PacketPlayerPosLook.EnumFlags.Z))
        {
            d2 += entityplayer.posZ;
        }
        else
        {
            entityplayer.motionZ = 0.0D;
        }

        if (packetIn.func_179834_f().contains(S08PacketPlayerPosLook.EnumFlags.X_ROT))
        {
            f1 += entityplayer.rotationPitch;
        }

        if (packetIn.func_179834_f().contains(S08PacketPlayerPosLook.EnumFlags.Y_ROT))
        {
            f += entityplayer.rotationYaw;
        }

        entityplayer.setPositionAndRotation(d0, d1, d2, f, f1);
        this.netManager.sendPacket(new C03PacketPlayer.C06PacketPlayerPosLook(entityplayer.posX, entityplayer.getEntityBoundingBox().minY, entityplayer.posZ, entityplayer.rotationYaw, entityplayer.rotationPitch, false));

        if (!this.doneLoadingTerrain)
        {
            this.gameController.thePlayer.prevPosX = this.gameController.thePlayer.posX;
            this.gameController.thePlayer.prevPosY = this.gameController.thePlayer.posY;
            this.gameController.thePlayer.prevPosZ = this.gameController.thePlayer.posZ;
            this.doneLoadingTerrain = true;
            this.gameController.displayGuiScreen((GuiScreen)null);
        }
    }