Using Flagpoll with VR Juggler 2.0

VR Juggler 2.0.2 introduced the use of Flagpoll as an alternative to the *-config scripts (vrjuggler-config et. al.). VR Juggler 2.2 and beyond require the use of Flagpoll because the *-config scripts have been removed. It is possible to use Flagpoll with VR Juggler 2.0.2 and newer to ease the transition to VR Juggler 2.2.

Install Doozer 2.1

To begin, Doozer 2.1.4 or newer must be installed instead of Doozer 2.0.0. For RPM-based Linux distributions, Doozer 2.1.x packages are available. See the VR Juggler download page for details on the Infiscape YUM repository.

Modify vrj.appdefs.mk

Next, the file $VJ_BASE_DIR/share/vrjuggler/vrj.appdefs.mk must be modified. The change is very simple, but it may interfere with other users and their use of a shared VR Juggler 2.0 installed. Make sure that everyone is aware that $VJ_BASE_DIR/share/vrjuggler/vrj.appdefs.mk is being changed.

First, we need to remove the (conditional) assignment of $(DZR_BASE_DIR) because, as we will see, it is set elsewhere. This line will be near the top of the file. It looks like this:

DZR_BASE_DIR?=         $(VJ_BASE_DIR)/share/Doozer

In Doozer 2.1, the file $VJ_BASE_DIR/share/vrjuggler/vrj.appdefs.mk is included by Doozer's ext/vrjuggler/dzr.vrjuggler.mk file. Thus, the file in $VJ_BASE_DIR/share/vrjuggler/vrj.appdefs.mk that includes ext/vrjuggler/dzr.vrjuggler.mk must be removed. Otherwise, a circular inclusion will occur, and GNU Make will run into serious problems. The line to remove looks like this:

include $(DZR_BASE_DIR)/ext/vrjuggler/dzr.vrjuggler.mk

Modifying a Doozer-Based Makefile

Finally, two simple changes must be made to VR Juggler 2.0 application makefiles based on Doozer. They are as follows:

1. Remove the line that includes $(VJ_BASE_DIR)/share/vrjuggler/vrj.appdefs.mk
2. Add the following lines:

DZR_BASE_DIR=  $(shell flagpoll doozer --get-prefix)
include $(DZR_BASE_DIR)/ext/vrjuggler/dzr.vrjuggler.mk

An example of the change to the Doozer-bsaed makefile is shown below as a unified diff:

--- Makefile.in (revision 19219)
+++ Makefile.in (revision 19220)
@@ -37,7 +37,8 @@
 srcdir=		@srcdir@
 SRCS=		MPApp.cpp main.cpp
 
-include $(VJ_BASE_DIR)/share/vrjuggler/vrj.appdefs.mk
+DZR_BASE_DIR=	$(shell flagpoll doozer --get-prefix)
+include $(DZR_BASE_DIR)/ext/vrjuggler/dzr.vrjuggler.mk
 include $(DZR_BASE_DIR)/ext/vrjuggler/dzr.vrjuggler.glapp.mk
 
 # -----------------------------------------------------------------------------

These are the very same changes that must be made for VR Juggler 2.2 use, and by making these changes, a VR Juggler 2.0 application makefile based on Doozer can work with both VR Juggler 2.0 and 2.2.