[Bf-committers] About programming Blender device control interface

[Campbell Barton]

On Wed, Sep 22, 2010 at 11:28 PM, Anthony LAU <lauliullt at yahoo.com> wrote:
> Hi!
>
>  I'm currently doing a academic research on creating a new interface that can
> translate the real-life actions into 3D coordinates. To test the efficiency of
> such system, it's best to test it with some existing 3D programs.
>
>  THis makes Blender as my first choice as I could access the source codes for
> ease of customizing the interface with Blender 3D environment.
>
>  I've already downloaded the SVN and is able to compile it in either 32-bit or 64-bit
> Window platform. I'm also trying to read the online documents to look for clues how to
> program such control interface in Blender.
>
>  Nonetheless, I'm still a bit lost on where I should start from, e.g. like which part of
> Blender is dealing with cursor control, handling mouse events, etc.
>
>  Would anyone mind giving me some clues or guidelines where I should start to look
> into on the programming the input interface? Thanks.
>
> Anthony

If you need to deal with event system internals we have a low level
library called GHOST, you'd probably need to use this if you wanted to
add a new input device or event types.
But this is really low level and I dont think its a good starting
point unless your main goal is to extend event system code.

Id suggest looking into existing modal operators, these are tools
which take user input, and handle their own events.

Examples are the knife tool, viewport manipulation pan/zoom/orbit, fly
mode, border select and painting tools.
These can be written in C or Python:
The view manipulation operators are in view3d_edit.c.

A python view-editing-template can be accessed from the text editor,
Text -> Script Templates -> Operator Modal Draw.
To run it first tun the script to define the operator, then use the
spacebar operator search menu in the 3d view to execute it.
See other view properties:
http://www.blender.org/documentation/blender_python_api_2_54_0/bpy.types.RegionView3D.html