S.K.O.B: Some kind of Bombjack (early WIP)

[+Nathan Strum]

This is probably closer to what the 2600 would do (and even then, this is an asymmetrical playfield, which has its own issues on the 2600):

 

[Atariboy2600]

Hum hey better then no backdrop^_^;

[LS_Dracon]

Nice playfield Nathan!

A way to display this is flickering. One frame display plataforms and bombs, in other display the playfield.

Edited September 8, 2007 by LS_Dracon

[Bakasama]

Given the limitations of the 2600, I think the best you can do is maybe a blue sky with something that vaguely looks like a pyramid for a background.

[Steril707]

Nice playfield Nathan!

A way to display this is flickering. One frame display plataforms and bombs, in other display the playfield.

 

I think you would not want to play that for longer than ten seconds.

 

(where is the vomiting smiley when you need it )

Edited September 8, 2007 by Steril707

[supercat]

I know Im not a programer and thsi maybe a huge pipe-dream idea but if theres anyway to add a backdrop image for each levels...

 

There's a limit to how much work the 6507 can do on each scan line. Just about everything is possible on the 2600 with the right trade-offs, but you have to decide whether the trade-offs are worthwhile.

 

The playfield is already required to show walls, and is probably required to show bombs as well. There may be ways of doing the bombs with missiles, but the prospect is a bit dodgy at best. It may be possible to interleave scan lines of different colors to show the walls, bombs, and backdrop, but making the bombs and walls stand out visually would probably be difficult. If you weren't trying for a backdrop, you could show the human and the bombs on one frame, and all the enemies on the other frame (30Hz flicker). Unfortunately, even 30Hz flicker only looks good when objects are displayed in front of a uniform dark background.

 

I think missilemen, with or without venetian blinds or flicker-blinds for the walls and bombs, are probably the way to go. Displaying 'men' with missiles is a little annoying, but not horrible. Half your scan lines will end with something like:

  lax (pf1a_shape),y ; #55
 lda (m_shape),y ; #60
 sta HMM1; #65
 stx PF1 ; First PF1 value for next line -- #68
 sta ENAM1; #71
 asl ; #73
 asl ; #75
 sta HMOVE; #1
 sta NUSIZ1; #4
 lda (p0_shape),y; #7
 sta GRP0 ; Assumes GRP1 was set elsewhere and is is v-delayed; #12
; #15

The choice of PF1 as the first 'visible' thing to hit was predicated upon the fact that if objects move in the central 128 pixels it's the first store you can do that needs to be done before the beam reaches column 16 of the next line.

[Steril707]

Using alternating scanlines, one showing walls, platforms and bombs and the other showing a backdrop would be possible without too much hassle.

 

Someone here who wants to convert Nathans Sphinx into usable PF data for the experiment?

 

 

 

edit/addendum: How are you getting pics into 1-bit mode (8 pixels = one byte) and reading the data out? I want to use that for my title screen, and the usual suspects (jpg, bmp, etc) don't seem to output the right data code.

 

edit2: Okay, i found out about this: Photoshop->convert to Bitmap, load into Hexeditor, copy hex as string into clipboard, paste into asm editor program.

Edited September 9, 2007 by Steril707

[Thomas Jentzsch]

Using alternating scanlines, one showing walls, platforms and bombs and the other showing a backdrop would be possible without too much hassle.

It might work with a low contrasting background and a high contrasting foreground. Else the background graphics will most likely become too distracting.

[Thomas Jentzsch]

Or something like this.

[Steril707]

Or something like this.

 

That might work, but if ithat's a visual advancement compared to the screen without a backdrop, i don't know...

Edited September 9, 2007 by Steril707

[Cybergoth]

I wouldn't bother much about the backdrop

[Thomas Jentzsch]

I wouldn't bother much about the backdrop

Agreed. After all, it's just eye candy and when it distracts from the gameplay it isn't even positive eye candy.

 

But at least it was worth a try, just to get an idea how it might have looked like.

[LS_Dracon]

Someone here who wants to convert Nathans Sphinx into usable PF data for the experiment?

 

Yes, I will do it.

Edited September 9, 2007 by LS_Dracon

[Thomas Jentzsch]

Yes, I will do it.

Problem is, that the vertical resolution needs to be reduced by ~50%. Maybe Nathan could do that best himself?

[LS_Dracon]

Like this?

I can convert both sizes in pf data, if Steril707 wants.

[Thomas Jentzsch]

Like this?

That's the best I can do too. Problem is, that Nathan's shading effects are gone none.

[Thomas Jentzsch]

Maybe this one is better?

bj.bin

Edited September 9, 2007 by Thomas Jentzsch

[Kurt_Woloch]

edit/addendum: How are you getting pics into 1-bit mode (8 pixels = one byte) and reading the data out? I want to use that for my title screen, and the usual suspects (jpg, bmp, etc) don't seem to output the right data code.

 

Hmmm... Title screen? Something like this?

[LS_Dracon]

Maybe this one is better?

Yes, good image Thomas.

 

I made my own, I don't work much on shading.

sphinx.bin

[Steril707]

So, if somebody is kind enough to give me the playfield file of that, i can try out if it works, and show you.

 

Hopefully i can finally get my coding computer connected to the internet around tuesday, so i can post my most recent .bin files. My girlfriend is already getting mad about me using her laptop all the time...

 

Mike

[Thomas Jentzsch]

So, if somebody is kind enough to give me the playfield file of that, i can try out if it works, and show you.

There you go. The data is for reflected PF mode.

bj.zip

[Steril707]

So, if somebody is kind enough to give me the playfield file of that, i can try out if it works, and show you.

There you go. The data is for reflected PF mode.

thanks...!!!

[Steril707]

Little Update:

 

* Title screen (still quite basic)

 

* one more layer of bombs and platforms added

 

* platforms work now (no walls yet though)

 

* small spaceman enemy to be seen (not moving yet)

 

* some animations added

 

If you collect all bombs or touch the enemy, the game jumps back to the title screen. It does ocassionally jump back to the title screen as well, for my routine checking up the number of the remaining bombs is still stupid as hell (adds up all remaining bits in the Bombs variables, and executes if 0. Sometimes adding up all those bits ends up in a zero as well, even if you still have bombs remaining).

 

Well, have fun..

 

Mike

 

 

 

 

 

Bombjack_v0_11.bin

Edited September 11, 2007 by Steril707

[gambler172]

Hi Mike

Looks great.Hope to see more.Bombjack on the 2600 would be a dream.

greetings Walter

[Kurt_Woloch]

Thanks for the new binary! Looks good so far... but I think you're overdoing it a bit with 40 bombs on one screen... I guess those are all the positions where bombs are possible?

 

* Title screen (still quite basic)

 

Yes, that's true, though I could imagine some simple ways to soup it up:

1. Let the 2 colors of the players "glow", that is, cycle between different colors (but maybe in a different order than the standard one of the Atari pallette... we've seen that too often now in other games.

2. Put some playfield graphics in the background. My favorite would be a blue vertical bar on a reflected playfield that simply changes its position with each frame so that it runs from the middle outwards, when it has reached the edge of the screen, it would start again in the middle. The playfield registers and colors would be set before displaying the title picture, so you don't need any additional writes in the 6-char routine.

Another alternative to that would be to "mask off" the title picture on the sides using the playfield graphics so that the title picture itself has two different colors than the border around it. Those two effects also could be combined by having the masked border and still a vertical bar which changes its position inside of the title picture.

Or... you keep the black border around the picture, but have an additional 4-pixel blue (or glowing) border around it which gets displayed by PF graphics.

Another idea would be to do the "spiral" above and below the box with the title picture. To do this, you would need two different spiral patterns... one would be exactly reflected, and the other gives a spiral if the bits are reversed in the right half from what they are in the left half. Together with reversing the colors, this would give a convincing "spiral" animation. If you use reflected mode (with correctly timed write for the inner PF byte), you only need to code 3 bytes per pattern line, because the right half is exactly the same as the left one, only in one of the patterns the bits are all reversed.

 

I've attached a modification of the screenshot you posed in order to show you some of my ideas. In it, you can see the blue border around the orange and red title box, and the spiral above and below it. Sorry if the colors aren't accuratly out of the 2600's pallette...

 

 

* platforms work now (no walls yet though)

 

Yes, I noticed that... though the flying logic could be improved too. Remember, you can "flap" in the arcade version which causes the falling speed to be zeroed on each press of the button. Oh, and when you run off the side of a platform, the falling speed also should start at zero (seems not to be the case now). And when pushing the joystick down, jumping isn't possible... in the arcade that results in an even smaller jump.

 

* small spaceman enemy to be seen (not moving yet)

 

Looks good and recognizeable so far. Bomb Jack himself somehow doesn't look that good, though, but at the moment I don't know how you could make him look better. Maybe you could color-stripe the main character? Would there be time enough in your 2-line kernal for that?