INVADER OF SPACE - new issue

[Baby Blue Azure]

The guys over there on BPM are working overtime and emotions are heightened. This is to be expected. The internal timer expires and the game still isn't done. I feel for Bob and Kurt as well. It's a mammoth job they've taken on. I'm staying off the BPM blog because I know they'd say SHUT UP! Same thing happened at Atari, so we don't need that again. But I do support them 100% and understand the sacrifices they are making. If I did go there I would be an INVADER OF SPACE, hence my latest entry. I'd like to thank Karl G for the inspiration of sprites for this game.

 

PHOTOS:

 

INVASION OF SPACE, BINARY:

INVADER_OF_SPACE_FA24.bin

 

INVASION OF SPACE, a78:

Invader_Of_Space_16K.a78

 

Enjoy this game and Godspeed to the BPM crew!

/BBA

[Tinman]

Looks very cool! But, what is the difference between the .a78 file and the .bin file?

[+SmittyB]

A .bin is an exact copy of the data as it would be on a physical ROM chip, whereas a .A78 file contains 128 bytes at the start that emulators can use to get information about the game like if it uses any additional memory.

[Baby Blue Azure]

That is correct Smitty B., thanks for replying. Credits should be made to PMP Bob for the original port design of Space Invaders to the 7800 - one of my faves. The differences between this release and Bob's final release (checksum = 5010) is this isn't based on Bob's final release, it's some iterative (down-rev?) version that I don't know where it came from. This version was used on Space Invaders Coke and Space Invaders Time Attack which I modifixed here. When the invaders close in to kill the player, they turn red in this game. The game name was changed and I had to fudge up the message length to allow extra characters, and of course the sprites were changed. It's a standard non-invincible game and fun to try, in my opinion. We have the disassembly of this and it would be interesting to see if we could change things up a bit more. Maybe increase the invader speeds but the invaders step down less each time across the screen. That could probably be simply done with 2 byte changes. And when you die you always start on the far left. I would prefer to start where you died or close to where you died. And the delay for the return of the player could be reduced as well. Maybe I'll look at this over the weekend.

[+Karl G]

I'm flattered that you liked the Space Game sprites enough to use them in your game! There seems to be some collision-detection issues, though, as I've had a few bullets go right through the aliens without destroying them.

[Baby Blue Azure]

Glad you like it Karl G. I noticed the collision problem as well. The game is too easy so you're penalized for not hitting the invaders dead center. Well, actually the invaders are wider with the new sprites so the fine collision detection needs to be tweaked. However, I tried this and it didn't seem to work exactly right. Unfortunately, this must be a downrev version of Bob's final release (cs=5010) so how this bin works is anyone's guess. I'll post an update here but if we go any further I need to shoehorn my changes into the cs=5010 version to have any chance that this will work 100%.

 

This INV2 version updates the UFO sprite so now all of Karl G's sprites are on display. Also, the invaders no longer go left and they don't drop down either. And the speed is much faster. And the UFOs can appear even when there is only 1 invader remaining - exposing another glitch, which wasn't intended but is happening anyways: With one invader remaining, wait for the UFO to appear and shoot the last invader and then try to shoot the UFO. The shot freezes and the UFO freezes as well. The next rack appears and you can take your time to shoot the UFO or go get him right away. The UFO scoring still functions properly. Also another glitch is the game plays racks 01 thru 09 and then plays racks 02 thru 09 forever, I guess. Unknown why the game does this either. So this is clearly a gadget/WIP game in progress for fun only.

 

PHOTO OF THE NEW UFO SPRITE

INV2 A78 FILE - PLAY ON THE EMULATOR ALL YOU WANT!

INV2.a78

 

ENJOY, BBA