Commando - Only 3 Levels - Mistake? Remedy?

[KevinMos3]

I was playing Commando the other day (up to about 700,000 points till I got tired of it), and noticed it only has 3 actual levels instead of 4. I always thought the 8 missions consisted of 4 levels (Duty 1) repeated twice (Duty 2), but I was wrong. I thought maybe there was something overlooked when it was programmed (wouldn't be the first time I've seen this -- like the colors for floor 4 of Xenophobe being the same as floor 3 when it actually has its own color table, but the pointer is wrong).

 

I got into hacking the colors and sprites (it started out as just seeing how closely I could copy the 7800 version player sprite into this), and I've noticed some things that just raised more questions.

 

Each level has its own copies of the sprites, color tables, and playfield data.

However, each level's ROM area includes palm trees which don't appear anywhere in levels two or three. I'm wondering if there was no intention of a level 4, or if it was going to use parts of other levels but just never got completed so level 2 was used twice instead...

 

How difficult would it be to add a distinct level 4?

How about changing one of those palm trees in the level 2 or 3 areas into a pillbox and using it in a level 4?

Could the playfield be used for hills and barriers along the sides of the screen instead of just mini hills and pits?

Are these things something a programmer would be willing to look into and take on?

 

This isn't intended to be a hack posting thread, but an actual questions/discussion thread. However, here's the sprite and color edits I did. I was able to get the sprite very close to the 7800 version, but then decided I didn't like the 7800's run animation, so here's the result.

• Player/enemy sprites changed
  
• Enemy color changed to gray to match the arcade
  
• Fertilized those mounds in level 1 so now green "grass" grows on top
  
• Sandbag barriers now tan instead of green
  
• Grenade boxes now green instead of purple
  
• Extra lives sprite edited
  
• Orange and blue bridges in levels 2 and 3 changed to gray
  
• Green of level 2 / 4 changed to be a little less bright
  
• Ground of level 3 darkened a bit
  
• Detail (shading) added to fortresses
  

Commando.bin

 

And I couldn't call myself Airborne without doing this.

Commando Airborne!.bin

 

 

 

 

Airborne!

Edited March 16, 2012 by KevinMos3

[KevinMos3]

329 views with no replies. I'm would think someone has information, or at least theories about this.

[PFL]

TBH, I haven't a clue but thanks for making the game pretty.

[KevinMos3]

I'm glad you like it. Wouldn't it be great if someone were to make a level editor? Can you imagine 32K and some good level variation?

 

The playfield is used minimally (mounds, barriers, pits, bridges, & fortresses). I would think more could be added for some really nice looking levels. Imagine some mirrored playfield data for the plateaus, hills, rivers (with a bridge across like the arcade), and reflected playfield data for ponds and small buildings/huts like the arcade.

 

I actually made a title screen, but I'm not good enough with assembly to integrate it. A nice end of duty screen could be done the same way, or even intermissions.

[PFL]

A level editor would be cool indeed. I really hope someone can help you out with that and the title/intermissions too. You've got a talent and it would be lovely to see your visions come true... and it wouldn't be bad to play it too!

[Omegamatrix]

I started disassembling Commando, but ran out of time. I'm in school now, and rather then letting this slip by I thought I'd just post what I had so maybe someone could use it.

 

 

Commando(re).zip

 

Each level has its own copies of the sprites, color tables, and playfield data.

However, each level's ROM area includes palm trees which don't appear anywhere in levels two or three. I'm wondering if there was no intention of a level 4, or if it was going to use parts of other levels but just never got completed so level 2 was used twice instead...

 

Commando is 16K, or 4 banks. The first three banks contain large chunks of the same data, including the main playing screen kernel. There are some minor color changes in this data, but little difference otherwise. It is clear that each unique level occupies one of these three lower banks.

 

There was some left over space at the end of these banks, and the programmer used it for other routines (like an audio routine, etc).

 

Now, the final bank is where most of the logic of the game is handled. In there most of the parameters are set up, and when it comes time to draw the screen the game will bankswitch to the particular bank holding the unique level it needs.

 

The palm tree is common to the main kernel, and that is why it appears in the three lower banks, whether it be used or not. You can hack it into whatever you want for each level.

 

 

 

How difficult would it be to add a distinct level 4?

How about changing one of those palm trees in the level 2 or 3 areas into a pillbox and using it in a level 4?

Could the playfield be used for hills and barriers along the sides of the screen instead of just mini hills and pits?

Are these things something a programmer would be willing to look into and take on?

 

These things probably would not be difficult. You should begin by expanding the rom to 32K to add more levels. Then set up a more efficient bank switching routine. Next work on the Main Kernel to allow using PF0. Once that is working do away with the macros, and replace each directly into each bank. Then you can edit the palm tree and other stuff. Finally look at the last bank to see how each level is set up. Although the disassembly is far from complete it should lead you in the right direction.

Edited May 12, 2012 by Omegamatrix