Re: [tuxracer-devel] Course precisions

[Steve B. <sjb...@ai...>]

Jasmin Patry wrote:
> 
> [Sorry for the delay in responding, I've had to devote 100% of my time
> over the last few days to finishing a term project...]

Tsk, tsk, tsk - get your priorities right!!  :-)


> There's a first cut at a damage system in 0.12, but you won't see the
> health display unless you include "health" in the debug variable in
> ~/.tuxracer.  It still needs work.  Paddling saps Tux's health, he takes
> damage when he hits a tree, and damage is also incurred based on the
> magnitude of the force exerted on him by the terrain.

In my first cut of my Tux game, I had the concept of "strength" or
"energy" and the concept of "health" or "damage" rolled into a single
variable.

This had some serious problems - and I eventually split them up into
two separate concepts.

Why?

Well, it's rather complex - but I think it's profound and applies to
Tux Racer as much as it does to Tux - A Quest for Herring:

1) I needed 'strength/energy' to limit the amount of 'flying' that Tux
   could do.  Being a Penguin, Tux can't exactly fly in my game, but
   flapping frantically does slow his falls and increase his jump
   distances.  However, if Tux was close to death due to damage, it
   seemed very wrong that a jump/flap should kill him.  Even worse,
   excessive jump/flapping would kill him and that's just plain silly.

2) It's almost a cardinal rule of games design that you shouldn't let
   the player get themselves in a position where you are wandering
   around in a level with no possibility of being able to complete it
   due to an earlier mistake.  That just leads to frustration - and
   the goal of a game is NOT to frustrate people unduly.

   With energy that you can just 'run out of', you might have a place
   in a level where you  need to 'flap' to extend a jump in order to
   complete the level.  If you can run out of energy then you can't
   possibly make the jump and you are frustrated.  I could (and did)
   fix that by providing 'Silver Herring' that Tux could eat to give
   him more energy.  But that wasn't enough.  You could still get to
   the point where you'd eaten all the herring you could ever reach
   and then run out of energy and THEN want to make that jump.

   The fix was to allow Tux's energy to gradually recharge. Slowly
   enough to prevent you leaping and flapping all the time - but
   fast enough to allow you to complete a level come-what-may.

   The trouble with *THAT* is that if 'energy' and 'damage' are the
   same thing then damage gradually recharges.  This makes it unnecessary
   to avoid hurting Tux because no matter how often he gets hit over the
   head or bitten by Killer Whales, you only have to find a safe place
   and wait around for a while and you'll be OK again.  That makes
   it really hard to design levels where the player has to be careful.
   He could always play recklessly and then wait for a recharge.

So, in short, I think it would be A Bad Thing for paddling to damage
Tux.  You would get to a point where you'd slipped into a hollow and
needed to paddle to get out - but had so much damage that you couldn't
afford to paddle.

I think you need to do what I did and split 'energy' (which gets drained
by frantic paddling - and which recharges either gradually over time -
or suddenly if you eat a really common silver herring)...and 'damage'
(which gets drained by hitting trees and such - and which cannot be
recharged over time - although there might also be a bonus thing that'll
repair damage).

This seems rather like real life.  If you get tired from running, you
can stop and rest - or drink a Gatorade (or so the manufacturers would
have you believe).  If you cut yourself, it takes a week to heal.

> > > 100? points for never using the paddle key
> >
> > I don't think you need to do that - if you have to resort to paddling,
> > you've already lost so much time that you'll get a bad time score.
> > No need for a double penalty.
> 
> Well, paddling at the start of a race gives you a nice speed boost.  But
> I like the idea that paddling saps your health.  Comments?

Energy - not Health.

Dunno - I'd suggest that once Tux reaches a speed higher than his
flippers can move, paddling would slow him down rather than speeding
him up - which happens to be a useful thing from a game play
perspective.  When you are going slowly (or stuck in a hollow),
paddling can somewhat speed you up - but you have to know when to
stop paddling if you want a really good speed.  That's kindof
analogous to Olympic bobsledders who have to know when to stop
pushing and jump into the sled.

Also, having paddling slow you down when sliding fast will be a
useful thing.  Not good for your time - but maybe needed by poor
players who are trying to reach a bonus item or avoid a tree.

That may mean that you don't need a penalty for paddling.  This
seems more natural to me.

> > For example, I have 'spinning herrings' in different colours
> > (Silver for a points bonus, Gold for a major prize, Red for
> > a random-ish special effect, Green for bad things you'd want
> > to avoid.  I use small spinning Tux icons for 'extra lives')
> 
> I like the idea of herring for health (I would use silver for small
> health boost, gold for big health boost)...

Yep.  Perfect.  I also use little spinning Tux icons for extra 'lives'.

Presumably, once you have health - and a need to score certain points
to get onto the next level, you need to decide what to do when Tux
'dies'.   Typically, this will simply force you to retry that course -
but if you choose to have a finite number of 'lives' - then if you run
out of lives then you also lose all your current points and have to
start the whole game over from scratch.

That's a pretty serious thing to happen - and in Tux_AQFH, I provide
plenty of free-life tokens to ensure that any player who is paying
attention will never run out of lives...but it does add another thing
that you have to collect and not run out of - which adds some more
richness to the game experience.

> ...but for speed boosts I favour
> some kind of symbol on the terrin itself -- chevrons have been used in
> so many racing games that they're instantly recognizable (which I think
> is a good thing).

Yes - I agree.  I havn't come up with a 'speed boost' thing for Tux_AQFH
because it isn't that kind of a game.

I agree that the red and yellow chevrons used in so many games have
become a 'culturally obvious' icon and to choose anything else would
be silly.

I'm starting to write a 'TuxKart' game (al'la Mario-Kart) in odd moments
(I've opened a SourceForge project for it to kindof reserve the name),
I'll certainly be using red and yellow chevrons for that.

The thing I *don't* like about that is that the graphic chevron implies
a direction.  In games like DiddyKong Racing (also N64), hitting a
chevron from one side not only boosts your speed - but also sends
you off in the direction that the chevron is pointing...Newtonian
Mechanics not withstanding.

I don't like that behaviour - and probably won't reproduce it in
TuxKart.
 
> Bonus points should be represented by something other than herring,
> IMHO, though off the top of my head I can't think of anything good
> (bowtie?  CD?  3-D /. ?)

I'd use a floating number (so you can see how many points it's worth
and you can decide whether it's worth blowing 10 seconds of time to
collect a measly 10 point bonus)...an alternative would be to use
coins of various colours - bonus points are kindof analogous to money
I suppose.
 
> I would make the teleporters look like portals of some sort -- say a
> (translucent?) polygon with an animated perlin-type texture, or something
> similar.

Yep.  That's what I did for Tux_AQFH.  I have a texture map that looks
like a 'sparkle'.  It uses an animation technique that allows the texture
to twinkle in an interesting manner by just translating the map sideways
by a carefully specified distance each frame.

In Tux_AQFH, I map that onto a billboarded circle.  It sortof looks like
a sphere (because the circle turns to face you - so it appears spherical)
but the fact that the texture is mapped onto a dead flat surface means
that it looks like a 'portal' or something.

Children have no trouble recognising it as a teleporter without me ever
telling them....which is amazing!

Anyway, you should probably download Tux_AQFH if you havn't already - then
you can steal my transporter and herring textures if you so desire.

For *displaying* current lives, health and energy, I use a row of tiny Tuxes
for lives, a row of 'life sparks' to show health and a herring that gradually
turns into herring bones as Tux 'consumes' his energy.  I had a lot of fun
programming that status bar.

I also have a pile of snowballs that depletes as Tux throws them and a row
of bubbles that show how much air he has left when swimming or wearing his
space helmet.

I wanted to avoid having numerical displays where possible - but I think
Tux Racer will need numerical timers (and perhaps bonus point counters).
 
> > You'd want to make it EASY to 'open up' the first few levels - but
> > make things increasingly hard right up to the end.
> 
> Right, that makes sense to me.  (I can't remeber what 1080 does...
> doesn't it have a few open at the start, and then they're opened up one
> at a time?)

Yes - exactly.

-- 
Steve Baker                  http://web2.airmail.net/sjbaker1
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