TROGBlog

Are you forgetting how our grandfather toiled under the yoke of Marathon steel with the Arizona sun above and the blinding arc of a welder below? If it wasn't for the galactic steel workers' union, he never would have been able to afford that above ground pool we frolicked in or the majestic golden van of our youth.

 

I think your beef is with the galactic trade cartel, a genuinely malignant organization bent on cornering the market on solar panels.

The player ship explosion sound reminds me a lot of the crash noise on the Odyssey2.

 

The game generally looks pretty good, though if I might offer a couple of suggestions...

 

-1- I don't know how many segments there are in the shields, but it might be nice to have the segments be grouped into clumps (larger clumps on the outside).

 

-2- If you could make one of the rings rotate opposite the others, that would be nice.

 

Star Castle was a classic, so it will be nice if it can come to the 2600.

If you absolutely have a need for three more bits of RAM maybe you'd be interested in this:

http://www.atariage.com/forums/index.php?s...5226&st=375

 

Question to the hardware gurus:

The undefined bits in SWCHB (2,4, and 5)...are these used at all by either console? In the update, I was attempting to EOR bit 2 (in the ram copy "DifSw") to signify a board reset...which looks to work OK in emulation.

I'm not a hardware guru but these bits are not used by either console. You can use them for RAM if you would like. Before doing so though you must set the bits data direction.

 

   lda #%00110100
  sta SWBCNT

The player ship explosion sound reminds me a lot of the crash noise on the Odyssey2.

 

The game generally looks pretty good, though if I might offer a couple of suggestions...

 

-1- I don't know how many segments there are in the shields, but it might be nice to have the segments be grouped into clumps (larger clumps on the outside).

 

-2- If you could make one of the rings rotate opposite the others, that would be nice.

 

Star Castle was a classic, so it will be nice if it can come to the 2600.

 

The ship explosion sound is standard Atari fare. Just a low frequency white noise with a decreshendo. The explosion for the cannon will be more involved, both in sound and graphics. I'm starting to code up an effect that will make the remaining shield segments implode into the cannon before it explodes, similar to the original Star Castle.

 

There will be 6 shield rings in the final game. 3 will rotate clockwise and 3 will rotate counter-clockwise, alternating every other ring. If you look in the source, you'll see that about 300 bytes of ROM was used to hardwire the logic for the clockwise shield rotation. It doesn't use a loop. The diagonal movement of the bits is too complicated for looping. The whole thing is unwrapped, and it took several hours to code it up.

 

Version 0.16 used square rings, so it was easier to implement in a loop, but it only supported 5 rings because of the extra 28 byte RAM buffer that was necessary.

 

The game level will dictate how many rings are activated. On early levels, there will only be two or three shield rings. On the highest levels, you'll have to blast through all 6 rings. The game will get progressively harder with each level, to keep the player on his toes. Difficulty variations will include the speed of the cannon rotation, the speed of plasma cannon shots, the speed of the missiles, the speed of the shield rotation, the number of rings in the shield, and another feature that will be disclosed soon. Also, on the highest levels, colliding with the shield will be fatal, rather than just causing the ship to bounce off.

 

If you absolutely have a need for three more bits of RAM maybe you'd be interested in this:

http://www.atariage.com/forums/index.php?s...5226&st=375

 

Question to the hardware gurus:

The undefined bits in SWCHB (2,4, and 5)...are these used at all by either console? In the update, I was attempting to EOR bit 2 (in the ram copy "DifSw") to signify a board reset...which looks to work OK in emulation.

I'm not a hardware guru but these bits are not used by either console. You can use them for RAM if you would like. Before doing so though you must set the bits data direction.

 

   lda #%00110100
  sta SWBCNT

 

Thanks for the info, but I probably won't get that squeezed for RAM. If I really need the extra RAM, there are at least 10 more bytes that I can wring out of the current implementation. It will just mean a more efficient use of temp variables, and some nibble encoding. I'm also trying to remove all subroutines from the code, or at least limit the number of nested subroutines to one level, so I won't have to reserve more than 4 bytes for the stack.