Edge line control on a prism.

[Anonymous]

I'm having problems with the way edge lines are displayed in elevation. This example is a simple square with the corners rounded off.

material mat
pen edgepen

crad=0.02	                !corner radius
wid=0.1		!width
hi=0.1		!height

put		0+crad, 	0,			15,
		wid-crad,	0,			13,
		wid, 		0+crad,		15+1000,
		wid,		hi-crad,	13,
		wid-crad,	hi,			15+1000,
		0+crad,		hi,			13,
		0,			hi-crad,	15+1000,
		0,			0+crad,		13,
		0+crad,		0,			15+1000,
		0+crad,		0,			-1

prism_ nsp/3, 0.02, get (nsp)

I can't seem to find a satisfactory way of consistantly getting an edge line all the way around when viewed side-on. I don't want to see the lines created by the curves, but changing the status code to 13 removes the very line that actually defines the boundary of the shape.

Does anyone have any tips or advice please? I'd be happy if I could get it to look 'correct' viewing from just the left and right directions.

[Anonymous]

Hi Peter,

Try this:

material mat 
pen edgepen 

crad=0.02                   !corner radius 
wid=0.1      !width 
hi=0.1      !height 

put      0+crad,    0,         79, 
      wid-crad,   0,         79, 
      wid,       0+crad,      79+1000, 
      wid,      hi-crad,   79, 
      wid-crad,   hi,         79+1000, 
      0+crad,      hi,         79, 
      0,         hi-crad,   79+1000, 
      0,         0+crad,      79, 
      0+crad,      0,         79+1000, 
      0+crad,      0,         -1 

prism_ nsp/3, 0.02, get (nsp)

HTH.

[Anonymous]

Braza, you are a genius! It's perfect!

Out of curiosity, do you happen to know where in the GDL Reference Guide this is mentioned. I've no idea what '79' actually does or how it works (but it does seem to work!)

Many thanks!

[Anonymous]

Oh... I recall my joy when I discovered it.

15+64=79

Its right there in the GDL Ref Manual page 139:

"j7: special additional status value effective only when j2=1 and controls the viewpoint dependent visibility of the current vertical
edge"

I'm Glad it helped.

[Anonymous]

Ahh, I found it - p171 AC13. It all becomes clear!?

Anyway, the fruits of my labour - A UK spec lightswitch!

[Anonymous]

Wow! First quality lightswitch.

BTW... I noticed some hided contour edges... Are you still using status code 13 on your prism?

If so, turn all status codes to 79 and only the visible contour edge will show up.

[Anonymous]

Thanks!!

They are all 79 now, and it displays perfectly in elevation from all angles. It is only in 3d that the corner curves have no distinctive edge, which doesn't matter too much.

I appreciate the help - thankyou.