Path: utzoo!utgpu!news-server.csri.toronto.edu!ois.db.toronto.edu!jonah Newsgroups: comp.arch From: jonah@db.toronto.edu (Jeff Lee) Subject: Re: Hardware mice pointers Message-ID: <90Jun17.102245edt.2802@ois.db.toronto.edu> Organization: University of Toronto, CSRI References: <136288@sun.Eng.Sun.COM> <6537@vax1.acs.udel.EDU> Date: 17 Jun 90 14:23:08 GMT Lines: 26 tomw@orac.esd.sgi.com (Tom Weinstein) writes: >And any X implementor who claims that X can't use a hardware cursor is >wrong. The X I'm running right now uses it quite well. To properly support X11, a hardware cursor should be at least 16x16 pixels, allow for user-specified "hot-spots", and provide two (arbitrary) colors plus "transparent". Furthermore it should be relatively easy/cheap to (1) move the cursor and (2) change the cursor. Some of the "older" workstations don't support all of these options (e.g. two colors) so the "standard" X11 (MIT version) usually doesn't use them. As it stands, the X11R4 "software" cursor can be moved programatically at a rate of around 400 movements per second on an 8MB Sun-3/60 (approx 3MIP) workstation (which has a memory mapped frame buffer). The biggest advantage of a hardware cursor is *not* that it can be moved quickly, but that (if it is a "sprite") it does not have to be unmapped before doing graphical operations which might overlap it. The biggest disadvantage is that there is typically only *one* (or some small finite number). Developers of multi-user collaborative software sometimes want users to see the mouse-cursor of other users as well as their own. If the hardware only supports a single cursor, you have to do the rest in software *anyways*. j.