Hi Brett,
In the CVS version, I have modified TPad::PaintBox to force the
box/width/heigth to be at least one pixel.
Rene Brun
On Fri, 27 Apr 2001, Brett Viren wrote:
> Hi Rene,
>
> Rene Brun writes:
> > TPad::PaintBox could be easily modified to set a minimum number
> > of pixels for the box.
>
> Ah, yes, I see this now.
>
> > However, you seem to imply that currently you have cases where
> > you do not see the box at all, not even one pixel !
> > Could you send me a very short macro with the box parameters
> > and the canvas/pad size to reproduce this problem ?
>
> I can't hit on the right parameters, but you can see the problem by
> doing the following:
>
> 1) At ROOT prompt, create a box, ie, with:
>
> {
> gROOT->Reset();
> TBox* b = new TBox(0.499999999999,0.4999999999,0.5,0.5);
> b->SetFillStyle(0);
> b->SetFillColor(1);
> b->Draw();
> }
>
> this will give you a 1 or 2 pixel size ``box''.
>
> 2) Resize (shrink) window. At, about 75% the original size I start to
> see the 1 pixel ``box'' start to disappear. Further shrinking and it
> cycles between appearance and disappearance (hmm, oscillating pixels,
> add this to MINOS's possible studies).
>
> I looked through TPad::PaintBox() and TGX11::DrawBox() but don't see
> any checks for the x1==x2 or y1==y2. I don't know what happens when
> XDrawRectangle() is called in this case ?
>
> -Brett.
>
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