New game: Earthraid

[LCD]

  Earthraid.png (Size: 3.03 KB / Downloads: 6,968)
Cooming soon: "EARTHRAID". This is a game published in 1986 for the Commodore C64. I made a Spectrum conversion of it. Its allready finished, but waiting now for a soundtrack.

[boriel]

And you did it in ZX BASIC??? hock:
Awesome!

[LCD]

And you did it in ZX BASIC??? hock:
Awesome!

Yes, it is done in ZX BASIC. The Water-Animation is slower than on C64, but C64 has a character-based display where if you change a font character, it is instantly updated on the entire screen. Spectrum has a bitmapped display, so the updates must be written everytime to all animated cells. But it the game is still excellently playable. Surely I could do it faster, but I think, the current speed is fully okay for a compiled ZX BASIC program and will cause some "Wow's!" on WOS . The Grow of Molusks (The invaders) is also slower than on C64, but this is a turn-based game.
I hope to get the music within 1 week.

[JBGV]

It seems a very good job.

We hope to play it soon ¡¡

[LCD]

It seems a very good job.

We hope to play it soon ¡¡

This is the original C64 version (available only in german): <!-- m --><a class="postlink" href="http://www.gametronik.com/site/fiche/commodore_c64/Earthraid/">http://www.gametronik.com/site/fiche/co ... Earthraid/</a><!-- m -->
My version is in english, has some additions like build-in instruction, missile visualisation, nice font, etc.
Expect it this week.

[slenkar]

looks very interesting

[LCD]

Update: Game available from my homepage.

[JBGV]

Where?

I can´t find it :oops:

This type of games I've always liked

[LCD]

Where?

I can´t find it :oops:

This type of games I've always liked

Go to the ZX Spectrum section of my homepage and click on the screenshoot. I hope you will like the game. For the sound effects I used BeepFX. 128K soundtrack was caned because the game uses all available ressources and this distrubed the interrupt routine too much.
Here is the direct link: <!-- m --><a class="postlink" href="http://members.inode.at/838331/zx/Earthraid.zip">http://members.inode.at/838331/zx/Earthraid.zip</a><!-- m -->

[slenkar]

nice little game, I was able to do level 1 easily but maybe the others will offer more challenge

[JBGV]

How do you do the water effect??!!

Awesome ¡¡

[LCD]

nice little game, I was able to do level 1 easily but maybe the others will offer more challenge

It is a almost 1:1 conversion from C64. The game plays exactly equal as on C64. The difference between levels is following:
For each level the mollusks lifetime is increased by two rounds, you must wait two rounds longer for a missile and there is less water.
Its not a question of winning, but the question of score.
By the way, I noticed that BeepFX crashes in ZXBC if is called inside a SUB:

Code:

Sub BeepFX(effect as ubyte)
  poke 60001,effect
  asm
    call 60000
  end asm
end sub

Outside subs it works fine.
On C64 the game took 4 kb by the way, but coded in pure assembler, on hardware that has character based display and sprites and SID. I had to use many tricks to make the conversion working, and these use much memory. Anyway, I'm happy with this conversion.

[boriel]

How do you do the water effect??!!

Awesome ¡¡

I was wondering the same!

[LCD]

How do you do the water effect??!!

Awesome ¡¡

I was wondering the same!

I used Britlions Putchars and two counters for animation frames: one for water (8 frames) and one for mollusks (4 frames), then scanned the playfield. Everytime a water or mollusk was detected, the tile was redrawn with new frame of animation. There was also a sup which redraws on a mask, to not let the helicopter or missile flicker over mollusks or water, as Spectrum has no sprites. I also though about a possibility to use a second screen to eliminate any flickering and tearing, but I wanted to make the game playable on Spectrum 48K.
So for the speed of graphics I credit Britlions PutChars routine.
I hope to show with this game on WOS how fantastic ZXBC is, and get more users who will use it. And to demonstrate the speed of development I released two games at same time.

[LCD]

How do you do the water effect??!!

Awesome ¡¡

I was wondering the same!

I will upload the sources pack later.