Re: [Fwd: Re: missing top border line]

[<br...@ph...>]

Ethan Merritt wrote:
> In 3D, draw_3d_graphbox() is called at the beginning of the plot,
> but any later calls are under the control of 'set hidden3d' and
> 'set grid {front|back}'.
> 
> The setting of 'set border {front|back}' has no effect in 3D.
> I don't know if that is a bug or if it is intentional.

A mixture of both, I'd guess.  Setting aside 'hidden3d', which does its 
own ordering anyway, the 3D graph box has always been drawn in two 
parts, IIRC: the back side edges are drawn before any plot elements, by 
draw_3d_graphbox(..BACKGRID), the front elements are drawn later (... 
FRONTGRID).  In a true non-map 3D plot, drawing the entire border frame 
in front would be wrong for every use except one: if you're trying to 
create an M.C. Escher effect.

The fact that 'set border {front|back}' doesn't have an effect on the
3D graph box is explainable by two observations:

1) in 3D, the grid is in the baseplane, and has a much stronger relation 
to the graph box.  Some of the parameters for drawing the base grid may 
not even exist outside draw_3d_graphbox.  So it actually makes some 
sense that 'set grid {front|back}' affects the border drawing, too.

2) Plain oversight: 'set border {front|back}' dates 2005-04-14, whereas 
the draw_3d_graphbox() code hasn't been touched since the 4.0 release.



> Probably the 'set view map' case should follow the 2D behaviour
> rather than the current 3D behaviour.  
> 
>> If this is a case, then all border lines should consistently of the same 
>> width.
> 
> They are.  The effect you are seeing may be due to the pm3d
> rectangles not being centered with respect to the same original as 
> the line segments.
> 
>> Further, they don't respect the "front" flag.
> 
> See above.
>