VisPy 0.12 released

[Lorenzo Gaifas]

Hi all,

On behalf of the vispy contributors, I'm happy to announce vispy v0.12!
Here are the main highlights:

- Better attenuated_mip shader for Volume visuals, which scales
automatically based on contrast limits
- Instanced rendering in gloo, with some examples showcasing how to use it
- Allow setting array to `symbol` in `MarkersVisual`

Several bugs were also fixed, and documentation was updated. For a complete
changelog, see https://github.com/vispy/vispy/releases/tag/v0.12.0

What is VisPy?
--------------

VisPy is a Python library for interactive scientific visualization that is
designed to be fast, scalable, and easy to use. VisPy leverages the
computational power of modern Graphics Processing Units (GPUs) through the
OpenGL library to display very large datasets. Applications of VisPy
include:

High-quality interactive scientific plots with millions of points.
Direct visualization of real-time data.
Fast interactive visualization of 3D models (meshes, volume rendering).
OpenGL visualization demos.
Scientific GUIs with fast, scalable visualization widgets (Qt or Jupyter
Notebook via jupyter_rfb).

See the Gallery and many other example scripts on the VisPy website (
http://vispy.org/).

Upgrading
---------

VisPy supports Python 3.x on Linux, Mac OSX, and Windows. VisPy's heavy use
of the GPU means that users will need to have modern and up-to-date video
drivers for their system. VisPy can use one of many backends, see the
documentation for details. We strive to keep backwards compatibility with
older versions of VisPy, but interfaces are still being designed to best
serve our users. As such, some things may have changed that break your
existing usage. See the Release Notes (linked below) for more information
on what has changed and contact the VisPy developers for help with any
problems you run into.

Links
-----

GitHub: https://github.com/vispy/vispy
Website: http://vispy.org/
Gitter (for chat): https://gitter.im/vispy/vispy
Mailing list: https://groups.google.com/forum/#!forum/vispy
Release Notes: https://github.com/vispy/vispy/blob/main/CHANGELOG.md

Contributing
------------

Help is always welcome. See our Contributor's Guide for information on how
you can participate:

https://vispy.org/dev_guide/contributor_guide.html

Thanks,
Lorenzo