> ## Getting Started with Entropy 3.0 under Linux/Irix

> ### September 1, 2001

> ###

> In the following discussion, we assume that the Entropy 3.0 distribution will reside in "/usr/local/exluna". To install in a different location, simply substitute "/usr/local/exluna" with the path corresponding to your desired location.

1. Remove any previously-installed version of Entropy

2. Unpack the Entropy 3.0 distribution
   Note that you may need root permission to create the /usr/local/exluna directory.
   `% mkdir /usr/local/exluna
   % cd /usr/local/exluna
   % tar xzvf Entropy30R1.mips3.tar.gz
   ` or`
   % tar xzvf Entropy30R1.linux.tar.gz`
   This will unpack the Entropy 3.0 distribution into `/usr/local/exluna/Entropy`.

3. Set the ENTROPYHOME environment variable
   Entropy uses the ENTROPYHOME environment variable to find default shaders and textures, the shading language pre-processor, and other files. You should set this environment variable in your shell initialization file (e.g. .tcshrc or .cshrc):
   ksh:`export ENTROPYHOME=/usr/local/exluna/Entropy`
   csh/tcsh: `setenv ENTROPYHOME /usr/local/exluna/Entropy`

4. Add `ENTROPYHOME/bin` to your path
   In order to run Entropy's various programs from a command prompt, you must add the Entropy 3.0 bin directory to your path in your shell initialization file (e.g., .tcshrc, .cshrc, etc.). For example, under tcsh, you could add the following line to the end of your .tcshrc file:
   `set path=($path /usr/local/exluna/Entropy/bin)`

5. Acquire and install Entropy 3.0 licenses
   See Entropy 3.0 Licensing for full details.

6. Recompile any previously-compiled Entropy shaders.
   If you have installed a previous version of Entropy, be sure to recompile any shaders with the new shader compiler.

7. Render a test scene from the examples directory
   In order to display rendered images, X Windows must be running.
   In a shell window:
   % cd /usr/local/exluna/Entropy/examples/scenes/vasegallery
   % entropy -d vasegallery1.rib
   An iv window should appear, and the image should begin to render.