Moments of Inertia by Rachel Crawford

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Tutorial: Maya 2015 Plugin Development with Visual Studio

Filed Under: Programming

Tagged: Maya, C++, Visual Studio, oldblogs

Another resurrected old post, I’m afraid. Hopefully it is still useful to somebody.

The Simplest Possible Plugin

  • Open Visual Studio. I’m using 2013, but this stuff ought to be transferable to other versions. With a bit of tweaking, anyway.
  • Make a new empty project. Give it a nice, descriptive name.
  • Add a new C++ source file called ‘hello_maya.cpp’
  • Copy and paste this code into it:
#include <maya\MSimple.h>
#include <maya\MGlobal.h>
 
DeclareSimpleCommand(HelloMaya, "Rachel Crawford", "1.0";);
 
MStatus HelloMaya::doIt(const MArgList& args) {
    MGlobal::displayInfo("Hello Maya!");
    return MS::kSuccess;
}
  • Open the project’s properties.
  • Open Configuration Manager, and set the active solution platform to x64.
  • Under General:
    • Set Target Extension to .mll
    • Set Configuration Type to ‘Dynamic Library (.dll)’
  • Under C/C++:
    • Under General, in Additional Include Directories, put Path\to\Maya2015\include
    • Under Preprocessor, in Preprocessor Definitions, add WIN32; NDEBUG; _DEBUG; _WINDOWS; NT_PLUGIN; REQUIRE_IOSTREAM; _USRDLL; MAYAPLUGIN1_EXPORTS;
    • Under Code Generation, set Runtime Library to ‘Multi-threaded Debug DLL’
  • Under Linker:
    • Under General:
      • Set Output File to $(OutDir)$(ProjectName).mll
      • Set Additional Library Directories to Path\to\Maya2015\lib
    • Under Input, add these to Additional Dependencies: Foundation.lib; OpenMaya.lib; OpenMayaUI.lib; OpenMayaAnim.lib; OpenMayaFX.lib; OpenMayaRender.lib; Image.lib; opengl32.lib;
    • Under Command Line, in Additional Options, add /export:initializePlugin /export:uninitializePlugin

Phew! The hard part is over. Build your project and you should get a file called ‘$your_plugin_name.mll’.

Now open Maya 2015. Navigate to Window > Settings/Preferences > Plug-in Manager. Scroll down the window to the bottom. Click Browse and navigate to and select your .mll file. Provided it loads correctly, it should appear in the Plug-in Manager window beneath “Other Registered Plugins”. Check the ‘Loaded’ checkbox next to it.

Now you should be able to just type “HelloMaya” into a MEL script or maya.cmds.HelloMaya() into a Python script and Maya will print // Hello Maya! // to the console.

So what does the code do? In Maya plugins, you create new commands as classes which inherit from the MPxCommand class. You create your class and give it a creator method and a doIt method. Then you write two functions, initializePlugin and uninitializePlugin, in which you register and unregister the new class with the Maya API. That’s a lot of busywork for a simple plugin which only adds a single custom command, though, which is why the DeclareSimpleCommand macro exists. It does everything except define the command’s doIt method, which is left up to you. The disadvantage is that it locks you in to having only one custom command in your plugin.

When you’re ready to move on, unload the plugin by un-checking ‘Load’ in the Plugin Manager. While the .mll is being used by Maya, we won’t be able to overwrite it with new versions of the plugin built by Visual Studio.

Next Steps

Now we’ll expand on our work so far to create a good starting point for a plugin project.

Scrap the current version of hello_maya.cpp and bring in 3 new files: plugin_main.cpp, hello_maya.h, hello_maya.cpp. You can get the source code for these here. This time, instead of using the DeclareSimpleCommand macro we go the long way around and do all the things it does by hand.

If it builds and works, you can take a look at the code yourself and see how a budding plugin developer goes about making new commands to use in Maya. Good luck!