From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: References: From: Lucio De Re Date: Thu, 18 Apr 2019 17:01:31 +0200 Message-ID: To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: text/plain; charset="UTF-8" Subject: Re: [9fans] Understanding /dev/draw Topicbox-Message-UUID: fae94e4a-ead9-11e9-9d60-3106f5b1d025 Whatever you do, do not start with Linux-type assumptions, or MIT-X assumptions. They will cripple your understanding. Everything is in the man pages, except the actual device driver, /dev/draw. VGA, if I understand your interest, you will be spared. I never quite understood everything involved in the Plan 9 graphics, but it all looked quite manageable. Lucio. On 4/18/19, Chris McGee wrote: > Hi All, > > I'm looking at creating an alternate filesystem for /dev/draw, /dev/mouse > and /dev/kbd that hooks up to a web server providing HTML interfaces (e.g. > canvas) for Plan 9 UI. I've been reading over the manual pages, which are > quite detailed, which is great, but there are some points of confusion for > me. > > In particular, /dev/draw's interface and documentation keep referring to > the concept of a "window" indirectly. It seems that in some cases the > server providing /dev/draw needs to track windows and refresh them. But, > what defines a window in this protocol? Is every image a window or only > some of them? > > Also, I'm trying to understand how off-screen images, such as fonts are > loaded. It seems that every image must be associated with a screen and be > given a position within the screen. So, how do you prevent the image from > being visible to the user? > > Hopefully, if I can understand some of the high-level concepts here then > the manual page will be all that I need. Does anyone have experience with > this area or could point me to information that might help clarify it? > > My next step will probably be to figure out how libmemdraw does all of this > on top of a frame buffer. > > Thanks, > Chris > -- Lucio De Re 2 Piet Retief St Kestell (Eastern Free State) 9860 South Africa Ph.: +27 58 653 1433 Cell: +27 83 251 5824 FAX: +27 58 653 1435