From: John Stone (
Date: Thu Aug 29 2019 - 15:24:40 CDT

  This is on my TODO list. I have to build a new FLTK, new Tcl/Tk
and various other libraries, and in particular FLTK and Tcl/Tk
have to be custom-patched to make them work. Since that work is
not really VMD-specific, I'm leaving to the end since VMD itself
has compiled in 64-bit mode on MacOS X for many years, but always
with issues from FLTK and Tcl/Tk GUI code (not ours). This is really
going to hinge entirely on the stability of the GUI toolkits.

A much more serious question about the long-term viability
of MacOS X now rests on Apple's announced deprecation of OpenGL
in favor of their proprietary (read non-portable) Metal graphics API.

There are some open source efforts underway to try and make OpenGL
code run on MacOS X through an emulation layer on top of the
proprietary Metal APIs, but so far ther're in their infancy.
Another option would be to run a Vulkan renderer on top of MetalVK,
a similar emulation layer that sits on top of Metal. That is more
apt to be a successful route, but requires VMD to have a completed
reimplementation of the entire interactive rasterization pipeline
in pure Vulkan, and I'm still only in the early stages of writing
that code since Vulkan itself has been coming along a bit slower than
I had originally anticipated.

You may have also noticed that Apple is also dropping support for OpenCL,
and they haven't had CUDA-capable GPUs in their machines for years.

To be honest, the future direction of the MacOS X OS platform is
starting to look like a poor match for scientific visualization
codes going forward. It may be that booting Windows or Linux on a
Mac ends up being a better way of utilizing the hardware to its
potential given what's been happening with Apple deprecating
the major cross-platform rasterization and computing APIs.

Anyway, one issue at a time. We've only recently gotten a Catalina
test box setup to work on ourselves, and we also discovered that
basic things like NIS/NFS etc don't work like they used to either,
so even our usual in-house development approach for MacOS X, with
use of network-based filesystems is problematic going forward.


On Thu, Aug 29, 2019 at 07:53:05PM +0000, Gumbart, JC wrote:
> Hi John et al.,
> The next MacOS is going to eliminate all support for 32-bit applications. Will there be a 64-bit VMD compilation made available for download in the near future, or should we compile it ourselves? (I have no idea how difficult it is to compile VMD on Macs!)
> I???ve already run into one person running a beta of Catalina who can???t install VMD. They were thinking of putting Windows on their Mac as a work-around???horrifying...
> Thanks!
> JC

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