Using Ogre 1.2.2 with Code::Blocks + MingW + STLPort
Table of contents
- Ogre 1.2.1 SDK for Code::Blocks + MingW + STLPort
- CodeBlocks Ogre SDK Tips
- CodeBlocks MinGW FAQ
MingW will statically link libstdc++ (the library portion, not the STL) to each dll or exe built. This creates a problem when passing strings and any stream types across dll's. Because the static linking has each copy of libstdc++ managing its own strings and streams, passing a string or stream to another dll and then having it modified there will trash memory. Ogre has several dll's and does pass strings and streams around. Do a debug build of Ogre with libstdc++ and then run it in gdb. You'll quickly find that OgrePlatform_d.dll crashes after the config window closes when it tries to modify/deallocate a string passed to it from OgreMain.dll.
A release build using libstdc++ "seems" to run fine for simple Ogre demos but if you start passing a lot of Ogre strings across dll's in a more complicated app, the app starts to misbehave. After a while crashes occur.
You could rebuild libstdc++ as a dll so that there is only one place where strings and streams are being managed.
That is what I tried. It does solve the problem, but there were still some issues. And doing the modifications to build a dll were a pain in the butt. Having used STLPort with vc6 back in 2003, I thought I would give it a try with MingW. STLPort 5.0.1 built out of the box with gcc 3.4.5 and was painless to setup up. It is used to build the dependencies and Ogre. STLPorts license is very clear too, but the license for libstdc++ as a dll doesn't seem so clear.
The MingW team has talked about supplying libstdc++.dll for many years (since 2000) but many roadblocks have prevented this.
Some links you can read about the issue:
The Ogre SDK comes with:
- all the Ogre modules built for you ie the dll's and static archives
- STLPort 5.0.2 pre-built + headers
- the Ogre manual in HTML format
- API reference in the form of a windows compiled help (.chm)
- All header files (*.h) for the libs/dll are included
- Source code and project files for 30 demos that you can compile and run as a confidence test of the SDK installation and to see what Ogre can do.
- All media resources required for demos
- Material Scripts + shader programs
- Compositor Scripts
- Particle Scripts
- Meshes + Animations
WARNING: this SDK requires the use of the latest Code::Blocks from svn HEAD and will not work with Code::Blocks 1.0rc2.
The SDK was built and tested with the following:
Download the following in the order given. MinGW must be setup before running Code::Blocks for the first time to make detection of MinGW go smoothly.
Download the following packages in the order given and unzip them in your MinGW directory ie C:\MinGW.
- use latest Nightly Build
DO NOT USE Code::Blocks 1.0 RC2 or earlier, you must use the Nightly build or build from svn HEAD.
- Do not install the Nightly build over 1.0 RC2 or you will experience crashes. Unzip the build into a clean directory. You can unzip Nightly builds into a previous nightly build with no problems.
There are two downloads you must get from the Nightly build post:
unzip wxmsw26u_gcc_cb.7z into the directory you will unzip CB into.
You may have to copy mingwm10.dll from the MinGW bin directory to the Code::Blocks bin directory if you didn't download it from the Nightly Build page.
There are some more detailed install instructions that can be found on the Code::Blocks wiki site
Make sure that Code::Blocks found your MinGW 3.4.5 installation by following these instructions here: Code Blocks Compiler Setup
Note: You do not need to download the dependecies package for Code::Blocks+MingW+STLPort, everything you need is included in the SDK.
The Ogre Core libraries and plugins:
In the settings menu select Compiler and Debugger to setup the directories.
Setup the include directories for the compiler.
Setup the lib directories for the linker. Note that DirectX SDK lib is not used. The import libs in the Ogre dependencies will be used instead since MingW cannot link directly to the libs provided in the DirectX SDK.
Include directory for windows resource compiler.
To build Ogre, open Ogre_stlp.workspace in Code::Blocks. Make sure you use Ogre_stlp.workspace and not Ogre.workspace. Ogre.workspace is for Code::Blocks 1.0 RC2 and does not use STLPort.
In the build menu select Build Workspace. This will build the debug and release targets of all projects listed in the workspace manager window.
When building Ogre for the very first time in Code::Blocks, a warning message will popup indicating that you must setup a global variable called stlport_dir.
Select OK and the Global Variable Editor will popup. All you have to do is fill in the base directory for stlport ie where you unzipped stlport in the dependencies zip and then select OK. The build process should then continue.
Note: The button to the right of the directory entry field will call up a directory dialogue so you can point and click the directory required. Do not fill in the fields below the Base Directory field.
The build process will take over an hour if all projects are built.
If you don't want to build the samples then use Save Workspace as... in the file menu, change the save name ie to OgreCore_stlp.workspace. Then close the Samples/projects you don't want and save again. You can use this workspace to build Ogre each time you update from cvs.
Here is an example of the minimum Ogre Core DLL's that must be built for the SDK. This assumes you need the BSP and Octree scenemanagers, both DirextX and OpenGL renderers, are using Cg shaders, and CEGUI.
Note: Code::Blocks builds the projects in the order listed in the Manager window. Dependencies have been setup so that if you decide to build a demo before the core libraries, the core library projects are built first if required.