BombJackNext Dev Blog

Discuss ZX Spectrum Next Games, Tools and more.
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ckirby101
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BombJackNext Dev Blog

Post by ckirby101 » Sat Jun 24, 2017 10:16 am

Ok as a quick "get back into Z80 dev and have a play" project i decided to write a Next version of BombJack from scratch..

Tools Used:

Z88DK (game is mostly asm but a few controls bits are easier with C).
Zeus (very quick to test using this EMU).
NextSpriteExtractor my tool for cutting sprites from a sprite sheet into usable asm files.
Sublime Text 3 great editor.



In game the raster lines are (running at 3.5mhz):
Green Sprite Update.
Red controls
White collision.

Link to video of game running so far... Not bad for a few days work which was mostly getting z88Dk setup and remembering z80 , last ganme i wrote in z80 was for GameGear in 1993..
https://dl.dropboxusercontent.com/u/573 ... ckNext.mp4
Last edited by ckirby101 on Tue Jun 27, 2017 12:10 pm, edited 1 time in total.

JoeZX
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Re: BombJackNext

Post by JoeZX » Sat Jun 24, 2017 10:32 am

Perfection.

Was waiting for "hoover maneuver" and .. there it is. So every cherry is/will be a 16x16 HW sprite ?

width - 28x8=224 pixels for main play area + side score board /256-224=32, nah/?
height - 28x8 = 224 pixels .. eh.


Arcade system:
Main CPU: Z80 (4MHz)
Sound CPU: Z80 (3.072MHz)
Sound Chips: 3 × AY-3-8910A (1.5MHz)
Video: 256×224 60Hz

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Baggers
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Re: BombJackNext

Post by Baggers » Sat Jun 24, 2017 11:03 am

Awesome work looks great!

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Kitty
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Re: BombJackNext

Post by Kitty » Sat Jun 24, 2017 11:07 am

Fantastic! I look forward to playing this on my Next in the future :mrgreen:
Image
www.vintageisthenewold.com #1 For Latest Retro Gaming News!

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ckirby101
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Re: BombJackNext

Post by ckirby101 » Sat Jun 24, 2017 11:43 am

So i'm using an extra 32 pixels in top border to fit the play area in.. The jump and fall tables are not correct yet plus its still very early days but i'm having fun with it...

Player ,bombs and enemy's will be sprites.
platforms will use Spectrum screen.
Background & right hand score panel will be layer 2.

JoeZX
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Re: BombJackNext

Post by JoeZX » Sat Jun 24, 2017 11:57 am

Thanks.

"Player ,bombs and enemy's will be sprites." - OK
"platforms will use Spectrum screen." - Ok
"Background & right hand score panel will be layer 2." - OK

.. but vertical resolution of your BombJackNext is 192+32 = 224 pixels .. so "over-border", global resolution will be non standard 256x224 pixel ? .. rendering in border, interesting .. I am asking coz we uneducated peasants dont know such details bout these things.

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ckirby101
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Re: BombJackNext

Post by ckirby101 » Sat Jun 24, 2017 11:59 am

The sprites can go in border.. And theirs no platforms in the border. If layer 2 can go into boarder great if not i feel a raster effect coming on to add a sky fade up there.. or even use a few sprites to add a little detail.. it will be fun working out what we can do..

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Flinnster
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Re: BombJackNext

Post by Flinnster » Sat Jun 24, 2017 12:00 pm

Great stuff :) For some reason I was exepecting the gfx to be redraws of the speccy original from Elite and not the arcade bitmaps.
One of my faves too!
Gamer. Pixelographist. Game Developer. Arcade Collector.

JoeZX
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Re: BombJackNext

Post by JoeZX » Sat Jun 24, 2017 12:03 pm

ckirby101 wrote:
Sat Jun 24, 2017 11:59 am
The sprites can go in border.
Yep, but isnt there a limit - 12 sprites per scanline .. 12x16=192 pixel strip .. or are you sprite multiplexing ?

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ckirby101
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Re: BombJackNext

Post by ckirby101 » Sat Jun 24, 2017 12:07 pm

no only the sprites , bombs and bad guys will be in border.. there no platforms up there.

if we can put layer2 background up there then great otherwise i'll use raster effects to blend into the layer2 background further down..

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