Where Are The Bats Created In The Bats Sample Code?

[blainelocklair]

Hi, everyone!

 

I'm guessing Nanochess has the best handle on this, but anyone that can answer is much appreciated.

 

I've looked at the code for the bats sample, and I can see the code where the sprites are generated. What I can't figure out is where the images for the bats, including both animation images, are located. I was expecting to see one of those BMP code sets with the dots and pound signs to make up the sprites. All I see in the code is the call to create the sprites. I looked in constants.bas and didn't see anything there that looked like that either. Where and how are the sprites stored?

 

Thanks!
Blaine

[+nanochess]

Hi Blaine.

 

The sprite uses the character designed by array f()

 

The array f() is filled alternately with $2d, $37 and $36.

 

These codes are used to retrieve the GROM characters, so I'm using letters M and W for wings, and V for attacking.

 

Note the SPRITE statement using f(a) * 8 and then adding the color. Using the GRAM I would need to add $0800 and of course changing the values filled into f().

[blainelocklair]

http://wiki.intellivision.us/index.php?title=Graphics_ROM

 

Very cool. I get it now. Very convincing animations from ASCII characters. I can follow the ASCII grid on the link above and see where the codes you used came from. Went from muddy to clear now. Thanks for your help!

 

Blaine

[+DZ-Jay]

http://wiki.intellivision.us/index.php?title=Graphics_ROM

 

Very cool. I get it now. Very convincing animations from ASCII characters. I can follow the ASCII grid on the link above and see where the codes you used came from. Went from muddy to clear now. Thanks for your help!

 

Blaine

 

Blain, check the IntyBASIC SDK folder "Documents/Tech" for a file called "grom.txt". This is an ASCII dump of the GROM chip directly from the ROM.

 

-dZ.

[blainelocklair]

Very cool. Thanks for letting me know about the doc on the GROM. I read it over to get a sense of what's in there.

 

So, to that end, are gridlines in games such as TRON Deadly Discs (non-moving) and BeamRider (moving) best done through the use of GROM ASCII? Two separate techniques here, I understand, because of the animation, but similar processes? I guess it makes things run more smoothly when the images are already in the GROM to be called upon.

 

Thanks!
Blaine

[+nanochess]

I think no GROM characters could account for these graphics, except for some horizontal lines.

 

So most of these are GRAM defined graphics.

[+DZ-Jay]

In TRON, perhaps some of the graphics use GROM, the ones that are card-aligned. in Beamrider, probably not. Take a look at the graphics in GROM and see for yourself.

 

By the way, it does not make it "smoother" to use cards in GROM. It works exactly the same as if it were on GRAM, except that you do not have to load them. It does, however, reduce the use of GRAM, which opens it up for additional custom cards to be used for greater detail.

 

For my own graphics, I have a tile ripper script I made that takes my artwork made in a sort of ASCII art format, and turns it into GRAM tiles. While doing so, it compares each tile with the GROM set to see if it can be replaced. If so, then that's one less GRAM card needed, which is now available for other background details or for sprites.

 

Take a look at this sample:

 

You may not know it, but there are many GROM cards in use there. Including, for example, the serifs (little decorative strokes) at the bottom of the "A" in "CAROL," and the "T" in "PRESENTS" -- those are the apostrophe character. Some of the straight lines on the presents' ribbons are also GROM cards.

 

If I were to use only GRAM, I wouldn't have been able to fit the entire screen in 64 custom cards.

 

-dZ.