Hi Fitz! I don't know what things were like years ago, but I know there is a lot of support now! I'm also with you on not using plug-ins or dll's. At least not until I know the full potential of DBPro without them. My experience so far is teaching me that most plug-in and/or dll functionality is already in DBPro, just a little more difficult to get at.
Anyone else reading this - please no flaming: I am not saying dll's or plug-ins don't have value or don't do things that DBPro can't do.
The question you are asking probably really should be in the DBPro Discussion board since it's a pretty advanced topic and you might not get the help you need here in the Newcomer's section. I'll give it a go though.
Because of the complex nature (high poly count) of terrrain .x models, the collision for the model needs to be set to polygons in order for it to work properly. The problem then is that due to the high polygon count, setting terrain collision to polygons will slow any system to a virtual halt.
The solution then is to not use the built-in collision system. You will have to write your own or find one on the forums. Basically, you are looking to use this command:
INTERSECT OBJECT(Object Number, X, Y, Z, ToX, ToY, ToZ)
Start by turning the collision for the terrain object off. Then use the Intersect Object command to draw a line down, directly below a character or object you want to interact with the terrain (i.e standing on it). Using a very short line, you can tell if the object is "standing" on the ground or not. You can use a similar method to check around your objects to detect collisions, such as walls, cliffs, etc. Check in the Snippets section. There was a very popular thread (still is I believe) using this method. I'll edit this post with the link or name.
Edit: Here's a good link:
http://forum.thegamecreators.com/?m=forum_view&t=10315&b=6
It's not the one I was thinking about, but it'll do.
Edit 2: Here's the one I was thinking of originally.
http://forum.thegamecreators.com/?m=forum_view&t=45212&b=6
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