chryses@xurilka.UUCP (Phong Co) (06/17/91)
Hi there,
I seem to have found an inconsistency with LPtoDP(). I'm using the
MM_ISOTROPIC mode, with the origin at the lower left corner (ie., a
negative yextent).
During a WM_MOUSEMOVE, I get the cursor position from lParam, convert
it to logical coordinates with DPtoLP(). At this point, I may decide
to modify these values. I then move the cursor to that location,
(possibly the same location), using LPtoDP() and ClientToScreen() to
get the proper coordinates.
The problem is that, even when I don't modify the location, the value
returned by LPtoDP() has a different y component than my original point,
in fact it is 1 less.
DPtoLP LPtoDP
(x, y) ---------> (x', y') ---------> (x, y-1)
Since I am moving the cursor regardless of whether I want the location
changed, the cursor drifts downwards until it reaches the bottom (0).
Does anyone else have the same problem. The functions shouldn't be very
complicated, it's possible the offsets being used are slightly off.
Thanks for your help.
Phong.
--
=========================================================================
Phong T. Co |
chryses@xurilka.UUCP | Nice girls don't explode.
dada Indugu Inc. | -- Dave Sim (Cerebus #110)
Montreal, CANADA |