[Coco] DynoSprite source code now available!

[Richard Goedeken]

Hi David,

I hope that others do make use of this and release some great games.  It would
have been awesome to have this in the Coco's heyday of the late 80s, but
unfortunately it would have also been much harder to create and use then.  The
Python script that I wrote for dynamic sprite compilation is extremely complex
and isn't even really feasible for porting to the Coco.  It's only with the
modern tools that we have now that we can push the Coco to its limits.

I thought about this a little bit today.  The 2 really distinctive features
that DynoSprite supports are:

1. Full-screen vertical and horizontal scrolling with 1-byte accuracy.  A lot
of people know how to do this in theory, but it turns out that it's very hard
to implement this correctly and with good performance.  Very few Coco games
ever used fullscreen X and Y scrolling; I can only think of Z89 and Gold
Runner 2K.  And due to other hardware limitations, this is about the only way
to go to get decent performance.  To get an acceptable frame-rate, you either
have to do fullscreen scrolling and limit your static graphics (lives
remaining, score, etc), or else use a *tiny* window.  There are some games
that I really love like Gantelet 2 and Super Pitfall which use windowed
scrolling, and despite how nice they look, they are really painful to play
because the frame rate is just horrible.  Play Super Pitfall on an NES and
you'll see that it's a totally different experience even though it's the same
game.  I would really love to see a Gauntlet style game with DynoSprite; it
could be really smooth.

2. The dynamically compiled sprites.  Although they're not orders of magnitude
faster than a general-purpose algorithm, they are as fast as you can hope to
get on the Coco.  You need every little bit you can get.

People could use DynoSprite for games that don't need the scrolling.  The code
could be removed and the graphics aperature halved, greatly reducing memory
usage.  But I think DynoSprite will really shine in games that make use of
both of these features.

Richard



On 12/03/2014 09:45 PM, David Ladd wrote:
> Richard,
> 
> Thank you for releasing such a nice powerful tool :D  I am sure those
> of us who always wanted to make a DiskBasic game can now do it :D
> 
> Now if you only you could go back in time and give it to people back then :D
> --
> David Ladd
> --
>