Date: Mon, 22 Apr 1996 12:10:11 -0700
From: ron@apple.com (Ron Hochsprung)
Subject: Item #337: Dev Sup Ext 0.6: "mouse" get-event clarification


P1275 Openboot Working Group Proposal -- Proposal #:337 Ver 1

Title:          Device Support Extension: "mouse" get-event clarification

Author:         Ron Hochsprung

Date:           4/22/96

Ed/Tech:        Technical

Synopsis:       define pos.x,pos.y interpretation

Doc & Version:  Device Support Extensions 0.6

Problem:

There is an ambiguity of how pos.x and pos.y are interpreted in the return
results of the GET-EVENT call for the "mouse" device.  In one implementation,
the values assume that 0,0 is at the top left, so that an increasing pos.x
value is down.  In another, 0,0 is at bottom-left and increasing pox.x
values are up.

Proposal:

add the following sentence to at line 46 of page 9:

  The coordinate system of x,y follows that of Open Firmware's graphics
  coordinates.  I.e., 0,0 is at top-left and increasing x values are
  down and increasing y values are to the right.

[ P1275 Item #337 -- Received: Mon Apr 22 12:09:19 PDT 1996 ]