BI temporary removal

BI Rewrite

Road map

There are two ways of how to achieve new Viewport

1. Make a new Render Engine and develop it keeping old Viewport.
2. Incrementally modify current Viewport.

Actually, I don't see reasons why we should do permanent removal of BI immediately. First way for me is more convenient, because in this case we will have a single code base for debugging and Viewports comparison at runtime. My proposal is to move BI to an addon.

Useful links:

https://code.blender.org/2014/09/viewport-project-targets-current-state-of-the-code/

https://code.blender.org/2014/12/future-viewport-the-design/

https://wiki.blender.org/index.php/User:Psy-Fi/TODO

https://wiki.blender.org/index.php/Dev:2.8/Viewport

http://www.frostbite.com/wp-content/uploads/2014/11/course_notes_moving_frostbite_to_pbr.pdf

Summing up, I conclude that this is not convenient to maintain old code to aim future Viewport. So it should be isolated. I'll try to weaken relations with kernel and learn the code.

Remove ~ temporary

1. Remove BI
2. Cleanup Viewport code
3. Refactor Viewport and keep BI part
4. Bring back BI as an addon (but without Texture nodes; see notes bellow).

Target is Cycles-like modularity.

What we have to keep?

• Shader Nodes
• Viewport part of BI

What we can move to the addon?

• All rendering algorithms and probably some BI specific DNA and rna props.

Goals

More convenient state of the codebase for further development

Current state and notes

Unfortunately texture nodes can't be moved to the addon and should be kept as well as Viewport part of BI, or can be replaced by the latest updates for procedural textures in Cycles Viewport.

Comparison BI, Viewport, Blend4Web [1]