Re: [Matplotlib-users] glumpy: fast OpenGL numpy visualization + matplotlib integration

[Christopher B. <Chr...@no...>]

Gökhan Sever wrote:
> This is technically called OpenGL backend, isn't it?

well, I think it's different -- he's not really using the standard 
backend API.

The trick with doing a real OpenGL back-end, is that a lot of 
computation time is spend doing transforms, and that can't be fully 
pushed to the back-end, because MPL provided arbitrary transforms.

There is also a fair bi tof time spent pushing data to the back-end.

I think to really get the benefit of OpenGL, you'd need the back-end to 
be semi-perstent -- you'd pass data in, and teh back-end would render it 
without having to pass the data in again. This would only support 
transforms that the back-end supports (linear only?). However, I think 
there could still be areal performance benefit bey breaking the 
transform pipeline into two parts -- one from arbitrary coordinates to 
something orthogonal and linear, and then a final one from that to 
screen coordinates (zooming and panning). Then you'd at least get full 
hardware accelerated performance for zooming and panning

We're doing this for a high-performance interactive mapping app, and 
it's working pretty well. However, OpenGL is pretty darn low-level, so 
there's a lot of code to write!

-Chris


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Chr...@no...