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TI Scramble - Scramble clone


Asmusr

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I'm thinking about making a Scramble clone, with smooth scrolling graphics, of course.

 

post-35226-0-83277400-1377637895_thumb.png

 

This is just screen shots from MAME pasted together. So I present this challenge: are any of you clever enough to extract the original graphics from the ROMs, in a format that would be useful for the TI?

 

The above is just the first level out of five, and they managed to squeeze all this into 26 KB of ROMs, including the program. It looks like 16x16 tiles were used, and they have probably also used some kind of compression.

 

And then there is the minor issue of how to shoot and drop bombs using a one button joystick...

 

---------------------------------------------------------------------------

 

9918A demo (emulated):

 

F18A demo (emulated):

 

Latest version: tiscramble-1.0.2.zip (the latest version fixes a problem with rockets appearing out of nowhere at the end of level 1, and also includes ROM images)

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I'm thinking about making a Scramble clone, with smooth scrolling graphics, of course.

 

attachicon.gifScramble1st edited.png

 

And then there is the minor issue of how to shoot and drop bombs using a one button joystick...

 

Maybe it's time we all got together and designed a new interface for the old TI. We can agree on a standard, make up a PDF file on how construct the device and interface the new socket to the keyboard matrix of the TI.

 

I guess we could start with one question... what kind of currently sold and easily obtainable controller do we want to use?

 

We are bringing the TI into the 21st century in memory, serial interface, super cartridges, video display and storage devices, so why not the joystick too?

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Other 8 bit systems of the day got by with one fire button just fine with workarounds like space bar for second fire or joystick down + fire etc. I find it a bit late in the day and pointless to be re-working fundamentals like joystick control unless it was to be part of a new hardware project like the F18A.

Would still love to see a TI99/4A version of Super Cobra (Scramble Clone) but Scramble is good, definately not enough shooters or platform games on the TI99/4A.

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Other 8 bit systems of the day got by with one fire button just fine with workarounds like space bar for second fire or joystick down + fire etc. I find it a bit late in the day and pointless to be re-working fundamentals like joystick control unless it was to be part of a new hardware project like the F18A.

Would still love to see a TI99/4A version of Super Cobra (Scramble Clone) but Scramble is good, definately not enough shooters or platform games on the TI99/4A.

Yes I think fire + down will have to do it. Pressing space bar while holding a TI joystick seems impossible, unless you use you feet.

 

I never playedSuper Cobra myself. How is it different from Scramble, except for the graphics?

 

Parker Bros made a version of Super Cobra for the ColecoVision:

 

 

That proves it can be done, but I was hoping to be able to improve the graphics somewhat.

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I find it a bit late in the day and pointless to be re-working fundamentals like joystick control unless it was to be part of a new hardware project like the F18A.

 

 

I dunno know, it always drove me NuTz using the joystick just fine in Parsec, but then having to take my hand off the joystick to change the "LIFT" with the 1, 2 or 3 key on the keyboard to go through the refueling tunnel. I cannot tell you how many ships I've lost that way. It would be kind of neat to wire a modern controller into the keyboard matrix to have the 1,2 or 3 key be available on the controller, not just the fire button. A couple of other keys like the REDO or BACK would be useful as well. Defender is another game that would greatly benefit from an upgraded game controller for the TI.

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yes, i purchased that gamepad (2 Gamepad), but maybe i am unlucky but they are not confortable playable... i must press buttons and directions very hard to have a result...

and more, are not the standard controller of the genesis but a compatible model...

 

maybe only my two controllers have that problems ? ... i do not know but the seller do not answered my emails. :(

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This is just screen shots from MAME pasted together. So I present this challenge: are any of you clever enough to extract the original graphics from the ROMs, in a format that would be useful for the TI?

 

The above is just the first level out of five, and they managed to squeeze all this into 26 KB of ROMs, including the program. It looks like 16x16 tiles were used, and they have probably also used some kind of compression.

 

And then there is the minor issue of how to shoot and drop bombs using a one button joystick...

It's possible to do this by yourself, MAME actually gives you the tools to do it. This can be done by pausing the game with the P key then holding the SHIFT key and hitting the P to move the on screen skip by one frame. Then you take a screenshot with F12 and you save it to the screenshot folder. This is very useful for objects with animations, like explosions.

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Yes I think fire + down will have to do it. Pressing space bar while holding a TI joystick seems impossible, unless you use you feet.

 

I never playedSuper Cobra myself. How is it different from Scramble, except for the graphics?

 

Parker Bros made a version of Super Cobra for the ColecoVision:

 

 

That proves it can be done, but I was hoping to be able to improve the graphics somewhat.

Arcade Version :-

 

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Doh! how did I miss that? That's very useful for extracting the tiles.

 

Then there are the maps left. It's interesting when you look at the TileMap viewer while the game is running how the screen is built one column at a time from right to left, but the entire screen is never scrolled. I assume the hardware had scroll registers, but I still can't figure out what's going on. Is anything known about the VDP that Konami used?

 

I noticed that in a column only the surface tile is unique, while the tiles below the surface (vertically) are all the same. Perhaps this is how the maps were stored, as a list of surface tiles and heights?

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After seeing what Bob did with the 7800 version, I decided to have a go at a Jaguar version, see the results here.

 

Anyway, Bob gave me the details of how the arcade game decoded the map, so... in the attached zip is:

 

konami.map - the binary data for the map from the MAME romset

CharMode.BMP - the bitmaps for the character set used, in windows BMP format.

 

The data format in the map is as follows:

 

There are 6 bytes that describe each *column* of terrain, laid out like this:
$00 - Number of filled zones from top of the screen (like in the UFO stage)
$01 - Character at the bottom of the above filler
$02 - Number of skipped zones from the top of the screen (starts the bottom terrain)
$03 - Character at the top of the lower terrain (from that point forward, the bottom terrain is filled like the top terrain)
$04 - Vertical zone of the below object ($00 if none)
$05 - Object placed: $00 - None, $01 - Rocket, $02 - Fuel, $04 - Bonus Item, $08 - Base
$FF - 'next stage', and you eat that byte (it doesn't count as one of the six).

 

If required, I can upload my 68000 assembly map parser for this data.

scramble.zip

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Thanks, CyranoJ :)

 

I ripped the layout directly from the arcade game, although while the arcade version processed two columns at a time, I changed it to process one.

Here is a 'Scramble Editor' that jwierer wrote, it will at least let you see the layout on the 7800 version (which is the same as the arcade version):

 

http://atariage.com/forums/topic/200470-scramble-editor-for-the-7800/

 

The 7800 bin is here:

http://atariage.com/forums/topic/192136-happy-new-year-scramble-for-the-7800/page-7

(post #161)

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Anyway, Bob gave me the details of how the arcade game decoded the map, so... in the attached zip is:

 

konami.map - the binary data for the map from the MAME romset

CharMode.BMP - the bitmaps for the character set used, in windows BMP format.

Thank you, just what I needed. With all this help I just have to make a TI version...

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Here is a 'Scramble Editor' that jwierer wrote, it will at least let you see the layout on the 7800 version (which is the same as the arcade version):

Thanks, but when I try to open Scramble.A78 in the editor I get an error:

post-35226-0-14470500-1377785814_thumb.png

 

What could be wrong? I'm using Windows 7.

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konami.map - the binary data for the map from the MAME romset

CharMode.BMP - the bitmaps for the character set used, in windows BMP format.

I can't seem to get the characters to match up with the map. They are supposed to fit together, right?

 

For instance, the first 6 bytes in the map file are: 00 00 13 10 00 00 (hex), but that would make the first surface character 10 hex = blue square with a red border, if I understand your decoding instructions correctly. In MAME it looks more like it was supposed to be character 8 in your character set.

 

Thanks,

Rasmus

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Add 32 bytes as an offset - so at 4bpp thats 64 tiles in for tile 0.

Thanks. I guess on the TI it's 1 bpp, so I divided the numbers in the map by 2 and now it works.

 

One more question: What do you mean by "$04 - Vertical zone of the below object ($00 if none)". Is that similar to the filling at the top or something else?

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Its either the offset from the top of the screen to the top of the bottom part of the map, or the offset from the lowest plotted char at the top - I can't remember right now I'd have to check.

 

LOL.

Edited by CyranoJ
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This is just my horizontal demo applied to the Scramble graphics. The graphics transfer nicely to the TI. I had to move a few ground items to allow for the color transitions. I expect to replace the rockets by sprites is the game, but I have kept them as tiles for the demo.

 

scramdemo.dsk.zip

 

The file on the disk is an E/A3 object file called SCRAMO

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