some things I'm confused on how to do...

[kilantolshi]

So I've been using Sandbox and reading through the forums for about two weeks now, and while I understand how to do most things there are still some things I am confused on how to do... I understand the tutorials and resources may not be the best place for this post, and if there is a more appropriate place I ask that a moderator move this to the correct location.

1.) how do you 'slope' materials (such as water/lava/glass)? I am trying to make a river that runs downhill but can't get the water material to slope with the ground...

2.) is it possible to add a sliding effect to glass to make it similar to ice (for an ice skating rink for instance)? would that be scripting, and if so how do you script the materials?

3.) I was trying to make a waterfall earlier, but all I can do so far is make a wall of water with billowing mist (smoke) at the bottom... how would one go about doing this correctly?

4.) though I've spent time looking through the forums, I could not find a tutorial on how to make certain keystrokes do certain things (i.e. make the 'b' button interact with an object, or make the 't' button select the nearest selectable target) I tried making the shopkeeper/quest script(s) but without a way to make the player interact with the target I can't test them myself

Again, any help would be appreciated. If some of these questions have already been answered elsewhere and I simply missed them, a link to the proper forum post would be just as appreciated. thank you.

[Hirato]

1) materials cannot be sloped, you can use the alpha material in connection with normal geometry to fake this for glass.
2) no, but there is a physics glitch you can exploit to a similar effect. Basically you create a diamond of slopes going from one to the next, I'll attach a screenshot a bit later
3) that's the closest we have to a proper waterfall, sorry
4) Those are called binds, you can find a lot of examples in data/ - I would suggest exercising caution.