Re: R: [stella] PCMSG 2.5 (Oystron?)

Subject: Re: R: [stella] PCMSG 2.5 (Oystron?)
From: Piero Cavina <p.cavina@xxxxxxxxxxxxx>
Date: Tue, 2 Sep 1997 20:06:47 +0100
there are so few bytes left that I can't add any new "serious" feature,
like a new enemy type.
Obviously, I can drop a feature for a better one that takes more or less
the same space!
Think that I've spent almost an hour converting two pieces of code into a
single subroutine to save about 15 bytes...

Glenn Saunders wrote:

>Here is my advice:
> Aesthetics
>Could you give the wing tips of the spaceship a different color?

Highly unlikely, thought I'm doing experiments. Too many instructions to
add in already very busy parts of code, where all the three registers are
already being used. You should have noticed that in most of the Atari 2600
games where the player is amongst the enemies, the player sprite is
monochrome, and this didn't happen because the programmers were lazy... You
can say...: ok, but yours is a double scanline thing... I will say: ok, but
I'm not David Crane... :)

>How about making a different life indicator?  Are there sprites left for
>that?  If not, why not moving the indicator down vertically where those
>sprites are free?

changed, smaller.

>Aesthetically I think we should try to avoid simple solid block graphics
>wherever possible.

ok... but don't touch the early bbblocky games, I love them!

>Fringing the pearls vertically with gradients of grey would also help, but
>may not be possible CPU-time-wise.

there's also the problem of the ball (one of the two player's shots) having
the same colors of the playfield...

>Also, it seems as if the ships/monsters pop off the screen when they
>scroll back to the right too early.  Is this necessary or can they get
>farther to the right of the screen before they disappear?


>As for the new flickering missile graphic for the boundaries of the
>pearls, aesthetically speaking these tiny graphics do not really fit in
>with the rest of the game, which is primarily double-line res sprites. Why
>not use the width register and bring them out a little more.

ok, the dots are made with missile 1 in single width/2 copies wide mode.
They can be expanded to 2,4,8 pixels width but I'm not sure that it would
look better. I'll let you see the results...

>If possible, why not make them random noise like in Yar's Revenge?  If
>this is too
>distracting, you could mute the colors so they stay relatively grey.

It's not possible to have a full vertical strip like in Yar's revenge, I
can use only missile 1 that is available only in one line out of eight.
I can easily drop the flicker, maybe it's better.

>Do you have any enemies that require 2 or more shots to kill?  This may be
>something to add as the difficulty ramps up, as well as upping the overall
>speed of the attackers.

I've done this modifying the behavior of the red enemies. Also, they change
direction at every hit. You can make them dance... very funny!

>Also, maybe you should penalize the player if a pearl is not taken and
>moves off to the right by having it mutate into a unique creature.

GREAT! Tried that, it takes only a few instructions. Looks like a great
It think that I'll make it work more or less in this way...

levels 1-4: pearls bounce to the right (easy)
levels 5-8: pearls disappear (annoying)
levels 9-12: pearls mutate into one of the "mild" enemies (dangerous)
level 13 and beyond: pearls mutate into a dangerous enemy (very dangerous)

>The reset switch is disabled during gameplay.  This is a nono.  Please
>restore it so that you can restart a game without having to actually end
>the current game.  On the SC you can not reset a loaded game just by
>powering down and back up again.


>Also please implement the "couch potato"


>reset hook to the fire button as all mid to late 2600 games do.


>Heck, you could hook the game select to up/down on the joystick too if you
>had the memory.

maybe, but this would be really the LAST thing, uh? :)

>As for game variations, why not building a matrix for options such as
>curvy shots, single vs. doubleshots, and whether you can group pearls

sorry, what's "curvy"?
As for the single shots, I think that they're always too boring.

>VERTICALLY as well as horizontally?  It seems as though a vertical bar
>would be harder to create than a horizontal one, because creatures that
>remove pearls are always coming in at different vertical spots.  It's much
>easier to "protect" a horizontal band and build there than it is to build
>vertically.  The more variations the better.  It's much better than
>hardcoding one or the other in there.

The "vertical rows" thing would be very interesting, but also much more
complex to code. Now to check a row out I need only something like LDA
ROW,Y... CMP #$FF, while for the vertical rows I would need a loop, a
table... not possible at this point. See below.

>Another option might be to make the spaceship 50-100% wider (vertically)
>so that one can no longer thread the needle just by shooting one enemy
>when three are coming at you.  This would REALLY make it difficult.

Nono, this would really make _my life_ difficult... :))

>Not having read any docs, I don't know how you are ramping up difficulty
>but there are issues such as extra lives, et. al. which will no doubt need
>to be fine tuned before you should stop development on this game.

I'm preparing a table to show how the difficulty is increased. I think it's
important an important thing to fine-tune.

>There is no way for you to know how easy or hard it is until we are
>allowed to play it for a while and give you our high scores.

Personally, I find the first levels too easy, but maybe it's because I've
already played the game a lot. I need to avoid the eventuality that it
becomes suddenly too difficult.

>If would be nice if this game had a difficulty curve that eventually beats
>all but the select few, so it's theoretically possible to continue
>playing, but only with pixel-accurate movement and frame-accurate timing.


>The sound is very good, but it suffers from there being no default noise.
>I'm wondering whether it ever uses both sound channels at once.  Does it?
>It would be nice if there were a general ship noise that it would default
>to and a "whoosh" when you change directions rather than the dead silence
>(other than the beaming in of enemies).

psycotronic "music" added :) I'll try to add a kick-drum, but I'm not sure...

>If you work on this stuff you'll have a title at least as good as any 4K
>Activision or Imagic title!

You're too good, they would have done a single-scanline resolution game! :)

>And remember, unless this game has to be a 4K
>ROM, if you run out of memory, don't be afraid to take advantage of the
>Supercharger's features.  The writable memory and the multiload
>capabilities are there to be exploited.

This project must be completed as a 4K thing, or the risk is of _never
finishing it_ .
In fact, I won't have the same time to spend on this program from these
days onward, and I can't start thinking about Supercharger programming and
new features now. It would take too much time.

But what I would really like to do in better times (let's say... around
Christmas? :) is a Supercharger-enhanced version. With more enemies,
power-ups, more bosses, **4-FRAMES-ANIMATIONS** ... all this and much more
should fit in the extra 2K.


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