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From: bcw@rti.rti.org (Bruce Wright)
Newsgroups: comp.windows.ms.programmer
Subject: Re: MDI devloper Pen Pal
Summary: One other thing ...
Message-ID: <1991Apr17.154621.903@rti.rti.org>
Date: 17 Apr 91 15:46:21 GMT
References: <25920007@hpkslx.mayfield.HP.COM> <DSAMPSON.91Apr16105552@x102a.harris-atd.com>
Organization: Research Triangle Institute, RTP, NC
Lines: 37

In article <DSAMPSON.91Apr16105552@x102a.harris-atd.com>, dsampson@x102a.harris-atd.com (sampson david 58163) writes:
>
> [Text, lines, and aliasing]
>
> If you look at the diagram in the Petzold book where he explains the
> tmHeight, tmInternalLeading, and tmExternalLeading, you can see that
> the area you have to play with in terms of drawing a line, is
> somewhere in the tmExternalLeading region.  So as plan B, I tried to
> trigger the line drawing off of a fractional relationship like this:
> 
> /* this is declared somewhere in the code */
> yChar = tmHeight + tmInternalLeading + tmExternalLeading;
> 
> /* now for the loop to draw the line between rows of text */
> for (y = 1; y <= someMaxNum; y++)
> {
>   /* location to draw line */
>   yLine = (yChar + .3 * tmExternalLeading) * y;
>   
>   /* then draw the line at yLine */
> }

One other thing - I don't know if this is just a typo when you
typed in your article, or if it's actually in your program (in
which case this could be most of your problem right there).

Shouldn't the location to draw the line be computed as

	yLine = yChar * y + .3 * tmExternalLeading;

Seems to me you have an extra factor of y * .3 * tmExternalLeading
in your expression (since tmExternalLeading is also part of the
computation of yChar).

Good luck -

						Bruce C. Wright