Behind the Scenes #1 news - CSPromod for Counter-Strike: Source

Hi, my name is Mike and I help out with development here for CSP. To give you guys a better idea of what we try to do, I'm going to write up a multi-part series about some of the work we have been doing this past year in closed beta testing.

Welcome to part one of this multi-part series.

One of the major issues with CSP's game mechanics was the way in which the source engine handles fall damage. In most Source Games you can fall extremely far and take very little damage. As with many things in Source, this would be unacceptable in the long run.

For CSP we wanted better replication of the fall damage to more closely match the values you find in cs 1.x. This is important because if you jump off heaven down to that first train car, or if you jump down from rafters on nuke, you should be given the same damage amounts as cs 1.x.

However, the issue is easier to say, then to do. You can't just change global gravity, because then projectiles and player jump height are screwed. So our coder amogan stated to really customize the values which control falling velocity for the player based on how high they fall from.

Now, the issue is, how exactly do you calculate the fall distances from one game engine to another? We tried jumping or falling from known locations in various maps, but it just didn't feel quite right no matter what we did.

Luckily, one of our testers from Australia, j0lt created two developer test maps. One for Counter-Strike 1.6, the other for CSP. Using textures that were pixel identical, he was able to create Unit Identical maps between the two games.

We are using these to test many different features now, and they are extremely handy. Heres a little screen of what they look like:

So, using these another tester from the UK, Brainkiller spent hours testing, and making unit specific data for the development team. Here are his findings:

"Brainkiller" wrote: Height Chart (In Exact Pixel Units)
1) 64
2) 128
3) 192
4) 256
5) 320
6) 384
7) 448
8) 512
9) 576
10) 640
11) 704

CSP Fall damage standing
1) 0
2) 0
3) 0
4) 11
5) 28
6) 43
7) 58
8) 70
9) 84
10) 96
11) 100+

CSP Fall damage landing in a crouched position
1) 0
2) 0
3) 0
4) 16
5) 34
6) 49
7) 63
8) 75
9) 89
10) 99
11) 100+

1.6 Fall damage standing
1) 0
2) 0
3) 8
4) 28
5) 43
6) 58
7) 71
8) 83
9) 95
10) 100+
11) 100+

1.6 Fall damage landing in crouched position
1) 0
2) 0
3) 15
4) 31
5) 48
6) 60
7) 75
8) 87
9) 98
10) 100+
11) 100+

As of this internal beta, those numbers match each other within less then 1hp.

In closing, it was a ton of work for multiple people, spanning across 3 countries 1/2 a world apart, but it really paid off. Although admittedly this may seem like a minor change, falling from rafters or heaven is a big deal again, and really adds to the polish and 1.x "feel" of the game.

Thanks for reading, and spread the word. See you soon.

-Mike