[Scilab-users] Changing polyline properties in param3d1

[Samuel Gougeon]

Le 18/07/2018 à 15:19, Izabela Wójcik-Grząba a écrit :
> Hello,
>
> I am looking for an elegant and simple way to manage with changing 
> properties of polylines in a param3d1 plot. The problem is that 
> sometimes (in case of specific data) there is only one polyline to 
> draw but in most cases there are many polylines. By now I solved this 
> problem by using "if" statement like below:
>
> param3d1(X,Y,Z);
>
> if size(X,'c')==1 then
>     gce().polyline_style=4;
>     gce().thickness=2;
>     gce().foreground=32;
> else
>     gce().children.polyline_style=4;
>     gce().children.thickness=2;
>     gce().children.foreground=32;
> end

You are right: it would be preferable to get always the same graphical 
structure, whatever is the number of plotted curves, as it is the case 
with plot2d():

--> plot2d(1:10)
--> gce()
  ans  =

Handle of type "Compound" with properties:
==========================================
parent: Axes
children: "Polyline"
visible = "on"
user_data = []
tag = ""

--> clf, plot2d([1:10 ; 1:10]')
--> gce()
  ans  =
Handle of type "Compound" with properties:
==========================================
parent: Axes
children: ["Polyline";"Polyline"]
visible = "on"
user_data = []
tag = ""

So, the same stable architecture shall be reached for param3d1().
Such a change won't be back-compatible, but searching for "param3d1" in 
all existing programs and updating them will be easy.
This change can be proposed for Scilab 6.1.
For the time being, i am afraid that using an "if" as you do can't be 
avoided, as in:

param3d1(X,Y,Z);
c = gce();
if size(X,"c")>1, c = c.children;  end
c.polyline_style = 4;
c.thickness = 2;
c.foreground = 32;

The last 3 lines should be replaceable with simply
set(c, "polyline_style", 4, "thickness", 2, "foreground", 32);
but there is a bug => being fixed

Regards
Samuel