GLBasic forum

Feature request => 2D => Topic started by: MrTAToad on 2015-Oct-14

Title: Clipping
Post by: MrTAToad on 2015-Oct-14
What would be useful is the ability to select a clipping area, so that anything outside this area isn't displayed.  This is somewhat different to viewports as a clipping area doesn't modify the current origin of graphics.
Title: Re: Clipping
Post by: Ian Price on 2015-Oct-14
You can do this with POLYVECTOR. OK, it' not as easy as selecting a rect (or other shaped) area, but it's not that much harder.
Title: Re: Clipping
Post by: spacefractal on 2015-Oct-14
VIEWPORT cant been used. Yes its does move x/y to its top corner on that VIEWPORT, but you can easy calculcate that.
Title: Re: Clipping
Post by: MrTAToad on 2015-Oct-14
Indeed, VIEWPORTS cant always be used as multiple overlapping viewports arent always allowed (OpenGL is very weird about that, although DirectX can be fine with it)
Title: Re: Clipping
Post by: Schranz0r on 2015-Oct-14
On a Tilemap?

You can draw a 1.000.000 tiles map with a simpl trick:
(btw. Old Code)

http://www.glbasic.com/forum/index.php?topic=966.msg5005#msg5005


simply draw things on the Screen not the outside one!
Title: Re: Clipping
Post by: MrTAToad on 2015-Oct-14
No, this is for objects on a pseudo 3d track, where multiple objects can overlay each other (which is why VIEWPORT wouldn't work).

I have been testing VIEWPORT, and another problem has cropped up with it, namely fractional parts (or rather a width or height < 1), mess up the positioning