¬ just serendipity 🍀 (not just serendipity)

I struggled a little to get started with Ogre3d graphics, so here are a few notes. In this post we will be able to run some basic examples from the framework.

Installation #

Get a distribution with a nice packaging system and install ogre from it. I can cite two: Arch Linux family (pacman-based) or Gentoo family (portage-based). The point is: DON’T install the ogre package from deb-based distros (Debian and Ubuntu).

They have a few problems:

1.1 Packages are usually outdated #

In the case of ogre, this isn’t a super problem. Its current version is 1.9, and Ubuntu offers 1.8. You can live with that.

1.2 Some files are missing from the packages #

I compared the upstream ogre tree (from Bitbucket) with files installed on Ubuntu (dpkg-query -L libogre-1.8-dev), and some files were missing. One example: SDK Trays.

1.3 Some files are installed in non-standard locations #

For example, x86_64-linux-gnu being used as a directory. This is non-standard. And what about /usr/lib/ogre? This folder doesn’t even exist on Ubuntu, but should!

Worse yet: Ogre documentation assumes the default installation directory is /usr/local. This assumes you don’t use a package manager and used make install after compiling, which requires sudo rights. This is too restrictive. Everything that ends up in /usr/local (programs installed manually) eventually becomes a mess.

Disclaimer: I’m not trying to convince you not to use Ubuntu for ogre3d development. I’m just stating I had an awful experience. If you can handle it, please comment how you did that!

I’m using Arch for ogre3d development now; if forced to use Ubuntu (work, lab), I’ll have to install ogre locally on the system.

Building with Arch #

pacman -Syu ogre

Now see if you can run the most basic pre-example from Ogre. Download it. Files include:

• ogreapp
  • CMakeLists.txt
  • BaseApplication.h
  • BaseApplication.cpp
  • TutorialApplication.h
  • TutorialApplication.cpp
• dist/ folder

There’s a CMakeLists.txt, so the build should be straightforward. Create your build directory, cd into it, cmake .. and make. Copy the OgreApp executable into the dist folder manually.

Note: The build system could be better. Just do it.

There’s a warning: see the plugins.cfg config file. Change /usr/local/lib/OGRE to /usr/lib/OGRE.

Basic Example 1 #

Get it from Ogre Basic Tutorial 1. Uncompress it, move its files to a ‘basic1’ directory, and copy CMakeLists.txt and dist/ from the previous example. Copy and paste the code from the wiki to TutorialApplication::createScene in TutorialApplication.cpp. Build as usual, and copy the OgreApp executable to the dist/bin directory. Done!

PS: I’ll likely write another post about Ogre.

Footnotes #

• The problem isn’t cmake (I had experience with it). The problem is the documentation. Ogre’s wiki is scattered. There should be one entry point for “getting started with ogre”, but there are several. A typical beginner struggles to decide which one to begin with. Documentation outside ogre3d.org is poor—forums, Reddit, blogs are either inactive, old, or poor.
• Bias: I love both Arch and Gentoo.
• PPAs? Please don’t use them.