the goal that never was..(how did he save that?)

Talk about EVERYTHING related to Kick Off 1 + 2.

Moderators: Rodolfo, Moderators, Rodolfo, Moderators

User avatar
Steve Camber
Mad! 7000+ poster!
Mad! 7000+ poster!
Posts: 7807
Joined: Sat Jun 16, 2001 12:00 am
Location: Sheffield, England
Contact:

Postby Steve Camber » Thu Jun 08, 2006 10:02 am

What Bob said!
--
SteveC - Kick Off engineer
18 Dec 2003 - "One day I'm going to disassemble the 68000 code, and find out exactly what's going on in there!! "

Ask me about online KO2 :) https://kickoff2.net
User avatar
gdh82
6000+ Poster!
6000+ Poster!
Posts: 6200
Joined: Fri May 26, 2006 8:16 pm
Location: Birmingham, England

Postby gdh82 » Thu Jun 08, 2006 12:21 pm

Thanks Steve and Bounty Bob - I appreciate the further explanation, even if my head is starting to spin !! Its easy to forget, I guess, that what the KO2 game is trying to create is a complicated 3-d business.

Going back to my original post, can you tell me about how the program checks the ball's position in 3-d space in relation to the goalie ? In asking about the goal-detection code (which I now realise is goal-post-detection code), this was where I was coming from. Re-reading this thread, you did point out that you hadn't looked at the goalkeeper code, so maybe I should shut up! :oops:

Thanks for any further advice though !!
User avatar
Bounty Bob
5000+ Poster!
5000+ Poster!
Posts: 5267
Joined: Sun Sep 19, 2004 7:16 pm

Postby Bounty Bob » Thu Jun 08, 2006 12:28 pm

I haven't looked at the KO2 code but considering when it was written and the technology base used, I'd expect something like:

The game knows the position of the keeper and the ball.
Each of these will have a virtual cube around them .
The keeper might have two collision areas, one for the upper and one for the lower parts of the body.
If either of these virtual spaces overlap with the balls space, then a collision between the two has been made.
If the ball has intersected with the bulk of the keepers upper box then make it a catch. If it's only just in there, then make it a fingertip save.
Keeping in mind what happens in fast moving instances with the ball and the goal posts, then you can begin to see where innaccuracies with the shot saving might come into it.
There will also most likely be an element of randomness to the keepers ability to catch, allowing for fumbles etc.

Like I say, I haven't looked at the code but I'd be surprised if it's a million miles away from what I describe. I've hope I've kept it understandable.
User avatar
gdh82
6000+ Poster!
6000+ Poster!
Posts: 6200
Joined: Fri May 26, 2006 8:16 pm
Location: Birmingham, England

Postby gdh82 » Thu Jun 08, 2006 1:35 pm

Thanks again Bounty Bob - that's very understandable and very helpful!

I imagine the size of the collision area will largely determine if the keeper 'saves' a shot even if the shot appears to his side. Added to that, I've got to take into account the collision areas are constantly on the move at varying speeds and directions. As you say, there's got to be some degree of inaccuracies which I just have to accept.

I guess in an ideal world I'd like what looks like a goal (i.e beats the keeper by, say, a body's width) to be a goal. In theory I imagine this would involve reducing the keeper's collision area - do you think that's realistically achieveable ? I recognise that is might not even be desireable to some and Steve has already made the valid point that this is just one of the game's charms (even if it still drives me barmy).

And I'm sure others would say I just want it to be easier to score goals so I should just polish up on my shooting skills!!! I'd still say I just want a goal to be a goal and a save to be a save!
User avatar
Bounty Bob
5000+ Poster!
5000+ Poster!
Posts: 5267
Joined: Sun Sep 19, 2004 7:16 pm

Postby Bounty Bob » Thu Jun 08, 2006 2:06 pm

Don't forget that there is a flip side to the impossible saves and they are the soft goals that should always be saved. Just look at the easy lob goals as example. It's swings and roundabouts.
Semtex
2000+ Poster!
2000+ Poster!
Posts: 2917
Joined: Tue Sep 03, 2002 12:00 am

Postby Semtex » Thu Jun 08, 2006 2:31 pm

Something that I'd like answered is:
Do the the keepers get affected by opposition players?
It seems a striker heading the ball will almost always cause the keeper to parry the ball straight back to the striker, whose forward motion carries the ball forward, into the goal...
Also, in the world cup I lost a game because when I ran the ball back to the keeper he parried the ball away, rather than, as I expected, simply picking it up (that's what normally happens) the oppostion striker was right on my defenders back. would that have affected the keeper? Did he 'panic'?
Robert
Moderator
Moderator
Posts: 16379
Joined: Fri Jun 15, 2001 12:00 am

Postby Robert » Thu Jun 08, 2006 3:09 pm

Steve that diagram of the goal....is it the same from the right hand side? I suspect not.
User avatar
Steve Camber
Mad! 7000+ poster!
Mad! 7000+ poster!
Posts: 7807
Joined: Sat Jun 16, 2001 12:00 am
Location: Sheffield, England
Contact:

Postby Steve Camber » Thu Jun 08, 2006 3:17 pm

Robert Swift wrote:Steve that diagram of the goal....is it the same from the right hand side? I suspect not.

Yes, the same theory hold for left and right.

Of course there may be deeper issues which mean squeezing the ball through the side netting may differ from left or right. Or maybe not ;)
--
SteveC - Kick Off engineer
18 Dec 2003 - "One day I'm going to disassemble the 68000 code, and find out exactly what's going on in there!! "

Ask me about online KO2 :) https://kickoff2.net
User avatar
Bounty Bob
5000+ Poster!
5000+ Poster!
Posts: 5267
Joined: Sun Sep 19, 2004 7:16 pm

Postby Bounty Bob » Thu Jun 08, 2006 3:38 pm

The diagram might be the same but maybe the code is different. :wink:
Robert
Moderator
Moderator
Posts: 16379
Joined: Fri Jun 15, 2001 12:00 am

Postby Robert » Thu Jun 08, 2006 3:43 pm

Let me start by saying that I am an expert practitioner of the 45 degree angle diagonal nearpost goal. Some of the Milan players can confirm this - when everything else is not working it absoutely is my get-me-out-of-trouble goal. For me, they are like the lob is to Steve Camber.

Now, right from the very earliest days of the game I have felt stronger attacking on the left post. In the end, this becomes a self-fulfilling propechy as you pick the straight shooting player on the left and tend to go for the shot more there.

Having said this, my belief is that either the keeper is weaker on that side, or the side netting hole is somewhat bigger, or both.

Steve, any light you could shed on this would be fascinating.
User avatar
Abyss
Moderator
Moderator
Posts: 5914
Joined: Wed Sep 18, 2002 12:00 am
Location: Athens, Greece
Contact:

Postby Abyss » Thu Jun 08, 2006 6:11 pm

And what about a probable difference between the up and down goal?

Isn't it easier to score from the top left side with the 45 deg shot Robert talked about than from the other three sides?
User avatar
Steve Camber
Mad! 7000+ poster!
Mad! 7000+ poster!
Posts: 7807
Joined: Sat Jun 16, 2001 12:00 am
Location: Sheffield, England
Contact:

Postby Steve Camber » Thu Jun 08, 2006 6:24 pm

Abyss wrote:And what about a probable difference between the up and down goal?

Isn't it easier to score from the top left side with the 45 deg shot Robert talked about than from the other three sides?

Possibly.
But no evidence has been found as yet, and I can't imagine what the cause might be. Could just be all in the mind!
--
SteveC - Kick Off engineer
18 Dec 2003 - "One day I'm going to disassemble the 68000 code, and find out exactly what's going on in there!! "

Ask me about online KO2 :) https://kickoff2.net
User avatar
Steve Camber
Mad! 7000+ poster!
Mad! 7000+ poster!
Posts: 7807
Joined: Sat Jun 16, 2001 12:00 am
Location: Sheffield, England
Contact:

Postby Steve Camber » Thu Jun 08, 2006 6:45 pm

Every player knows how far he is away from the ball, it's used all over the place.

When the goalie is in the air, jumping to catch the ball, the distance from the ball is checked. Then, if the ball height is between 10 and 32 units, and the distance is less than about 9 units then the keeper is given a chance to intercept the ball. This is based on the keeper's goalkeeping skills and a random factor.

Either
1. He catches it
2. He blocks it (Y velocity negated and halved, X and Z velocities given random adjustment)
3. He fumbles it (X and Z velocities given random adjustment)

So, when it comes to collisions, players are treated like (always upright) cylinders, and the ball is treated as a point in space.
--
SteveC - Kick Off engineer
18 Dec 2003 - "One day I'm going to disassemble the 68000 code, and find out exactly what's going on in there!! "

Ask me about online KO2 :) https://kickoff2.net

Who is online

Users browsing this forum: No registered users and 3 guests