[Vm-dev] [squeak-dev] Backing a Form with e.g. mmap() or shm

[tim Rowledge]

Isn't there already support for external bitmaps/surfaces? I remember doing some things that feel related to this with andreas decades ago

> On 2022-06-23, at 10:41 AM, Eliot Miranda <eliot.miranda at gmail.com> wrote:
> 
> 
> 
> On Thu, Jun 23, 2022 at 10:28 AM Tony Garnock-Jones <tonyg at leastfixedpoint.com> wrote:
> On 6/23/22 18:15, Eliot Miranda wrote:
> > Can you say more about your use case?
> 
> I've been implementing the X11 protocol in pure Smalltalk and I want to 
> use a little bit of FFI to shmget/shmat and use that to get the pixels 
> over to the X server. At present XPutImage is working but flooding the 
> server with XPutImage seems to run into a rate limit from time to time 
> so it's not very usable. Best to switch to mmap/shm if I can.
> 
> Technical:
> 
> So in this use including the header in the first page would be ok?  Would the mapping be read-only from the perspective of the X server?  Do you need shmget to be run via the FFI or would it be OK to invoke it implicitly as part of a mapping allocation primitive?  Would it be better to create the mapping via the FFI and provide the mapping to the allocation primitive? How should the mapping be taken down?
> 
> Windows folks, how portable is this idea to other OS's, especially windows?  (I'm guessing this is a standard facility on most leading OS's).  So would it be worth evolving towards a cross-platform abstraction?
> 
> Procedural:
> Would you be prepared to build the VM to test this?  Perhaps even generate it from sources?  To what extent would you be able to collaborate with e.g. Tom & myself in implementing this?
> 
> _,,,^..^,,,_
> best, Eliot


tim
--
tim Rowledge; tim at rowledge.org; http://www.rowledge.org/tim
Strange OpCodes: START: Cancel preceding jobs in queue