Drawing

[Golden-Death]

If I wanted to draw with a pen like function on the ground in game for others to see, what would be the best method?

[Megiddo]

Quads are the only direct thing you can use from lua to draw lines in the 3D world. You could also create small rectangle models and use those.

[Golden-Death]

Mm itd get really laggy. I was thinking of using such a drawing gun in a gamemode

[JamminR]

It would be difficult, but you could 'attach' GmodRects to 3d point(s) in space and convert it to 2d the same way my targeting system does.
Once that point was set, you could use any Rect material you wanted to do different things. I could see various 'materials' being created and drawn on a wall. One point for each material.
No where near as laggy as quads. (but, not in 3d space either, would only really look well when looking at a flat wall.)
Could adjust for size depending on distance away, to attempt to give a 3d look to it.
Use different materials, circle, angle, lines.

Sounds painful, but possible.

I'm going to have a LONG learning curve I think, but I'm really looking forward to what can be done on client end of GM10

[Golden-Death]

Or thinking about it, I could use a trail sprite like in lasertag or whatever that bouncy laser game garry made is and have it be drawn where you're pointing.

[Megiddo]

You could use ropes!

[Golden-Death]

But what knot would i use? 

[Mank]

Haha, I think that would be a cool thing to have.