Sliding Collision?

[Supermonkey]

I'm not much of a maths whizz, the most I did was an intro to 3D graphics course at uni and I was litterally in tears whilst doing the coursework . Infact my lack of maths knowledge is why at a very young age I realised I wasn't ever going to be a games programmer.
However, now many years later I'm interested in doing a bit of games programming. I've taken a look at some tutorials and their is just too many calculations for my liking, does anyone have a working example I could look at?

I tried searching the forums, I only found some code of davy's that was no longer available for download.

[DJLinux]

What do you mean with Sliding Collision ?

Joshy

[Supermonkey]

Well the response to the collision is for the object to slide along the plane of the other object, it's commonly seen in FPS games. When you collide with an object it doesn't cause the player to get "stuck".

[shadow008]

why not instead of when colliding with an object to stop, just deflect velocity?

[Supermonkey]

Wouldn't that have the same effect (i.e. stop the player)? I'm thinking in a 3D world, handling walking up ramps, going up stairs, walking on a terrain, these would all use a "sliding" response would they not? My understanding of collision detection/response doesn't go much past 2 dimensional techniques, such as basic boundary checking and some simple line/ray intersect.

[matthew]

I don't know if they're the ones you're looking for but I've done some searching on my hard-drive & found some of the terrain collision programs that davy *wrote* a while back.

Attachments:

[Supermonkey]

Yep, that's what I was after, cheers .

[edit]
Ah it's not as hard as I thought. Usually tutorials are a good thing, in this case just looking at code was a lot easier.

[matthew]

You might find this useful as well, when Xenovacivus created his collision detection dll he also wrote a program in C++ that would load an .obj file & let you move around it. The source is included too.

Attachments:

[Supermonkey]

That's even better, thanks .

[twasik4]

Those downloads seem like a job for my file sharing website for B4GL xD

[DJLinux]

With the Colllision Plugin you get all infos you need.

The triangle of collision the point of collision and the face/triangle normale.

The angle between the face normal and players direction are simple
the dot product.

CosAngle = DotProduct(FaceNormal, PlayerDirection)

Now mirror the PlayerDirection soft or sharpen around the FaceNormal

Joshy

w = wall
pd = player direction
pc = point of collision
fn = face normale
s1 = from soft
s2 = to
s3 = hard sharped new player direction

top view

  w     pd
  |    /
  |   /
  |  /
  | /
  |/
  pc-------fn
  |\\
  ||\ \
  || \ \ 
  ||  \  \
  | |  \   \
  | |   \   \
  | |    \    \
  | s1    s2   s3