Re: [Texmacs-dev] Displaying table grids

[Joris van der Hoeven]

Dear Norbert,

On Mon, Dec 14, 2009 at 09:39:09PM +0000, Norbert Nemec wrote:
> in fact, I had initially intended to make the lines 1px wide just as you  
> describe. After some fiddling I found that it always ended up looking  
> strangely asymmetric. The problem is that the cyan environment frames  
> are always 1px-wide lines outside the box, defining the box boundaries  
> to sit exactly between pixels. A 1px wide line can therefore only sit  
> either to the left or to the right of the box boundary. Any way you  
> choose this, it looks crooked. The only solution to allow good-looking  
> 1px-wide grids would be to shift the cyan box guides as well as the red  
> selection markers.

Hmm, I still would like to see this.

> Ultimately, though, I found that 2px lines actually have the advantage  
> that they can be displayed in fainter gray while still giving the same  
> visual impact. This should reduce the visual clutter with the black page  
> content.
>
> As for the eqnarray* grids - indeed that look takes some getting used  
> to. After using it for some time, I actually began to like it. I am not  
> quite sure how to change this cleanly. Currently, the whole code is  
> really simple, drawing a rectangle around each cell individually. Trying  
> to find adjacent cells and then determining the line between is  
> certainly much more messy and may be quite tricky to get correct for  
> cell spans etc.

I think that one ultimately gets used to about any convention.
Nevertheless, the first impression is important, and it still seems
a bit messy to me. But I think that it should be possible to do
something about it. Also true that the implementation will be non trivial;
the current solution is definitely the easiest one.

> Actually, do you have an idea what the mechanism is that causes the  
> space between the lines in eqnarray* ? I never managed to cause the same  
> effect in a table.

This is just the interparagraph space.

> Currently, my own major grievance with the table grid code is that cell  
> borders are hidden *behind* the grid. I tried to put the visual hints  
> behind the text, but this did not work nicely with overlays (which I use  
> heavily in one special layout). As I said, alpha-channel rastering would  
> be the perfect solution for this...

Yes, we should try to implement alpha rendering sometime soon;
this should be possible with the Qt port.

Best wishes, --Joris

PS: happy christmas to everybody on the list;
I will be off for a long week.