Re: [matplotlib-devel] Kivy backend

[Cyrille R. <cyr...@gm...>]

> Note that with OPenGL in general, its the transforming that buys you
> performance -- when you push brand new data to be rendered, it takes a lot
> of time to push that data to the video card, so drawing the first time
> doesn't buy you much. But if you need to re-render that same data in a
> different view, say zooming in or out, etc, then GL can fly -- if that
> transformation can be done on the GPU.
>
> As far as I understand it, that's what vispy is doing.

Exactly. Note that pushing data on the GPU is not that slow: in one
second, you can send hundreds of millions of points on a modern GPU.
However it would be a bit slow to send large amounts of data at every
frame.

GPU-based transformations are extremely fast, and you have full
control on how they're implemented; in the end, it's just arbitrary C
code that runs on the GPU on a per-vertex or per-pixel basis.