Videopac / Odyssey2 forum

Programming the Videopac / Odyssey2 => Homebrews => Topic started by: Chris! on September 13, 2019, 11:35:48 PM



Title: Chris the Cranberry
Post by: Chris! on September 13, 2019, 11:35:48 PM
Time to get back into the Odyssey 2 scene. I'm going to make a new racing game in the style of Excitebike and MotoRodeo (more info on MotoRodeo for the 2600: https://atariage.com/software_page.php?SoftwareLabelID=1020 (https://atariage.com/software_page.php?SoftwareLabelID=1020))
I'm calling it Chris the Cranberry. Here is its title screen, all I have so far.
(http://www.atari2600land.com/odyssey2/christhecranberrytitlescreen.png)

I got my Odyssey 2 out and it still works great.


Title: Re: Chris the Cranberry
Post by: Chris! on September 14, 2019, 03:42:39 AM
Added a timer to display during the race. It works fine on a real Odyssey 2 and O2EM but for some reason runs really slow on Homer.
(http://www.atari2600land.com/odyssey2/christhecranberrytimer.png)


Title: Re: Chris the Cranberry
Post by: Chris! on September 14, 2019, 06:20:51 AM
Figured out that that timer is incorrect. This version should have a better timer, but I had to sacrifice the hundredths digit.


Title: Re: Chris the Cranberry
Post by: Rafael on September 14, 2019, 06:32:27 PM
 8) 8) 8)


Title: Re: Chris the Cranberry
Post by: Chris! on September 15, 2019, 06:10:36 AM
Added the first obstacle: A big box.
(http://www.atari2600land.com/odyssey2/christhecranberrybox.png)


Title: Re: Chris the Cranberry
Post by: Chris! on September 16, 2019, 03:26:35 AM
HELP!
Suppose I want to have the boxes be various y positions.
I have this code:
Code:
boxydata:
db 029h, 039h, 049h, 059h

add a,#boxydata & 0ffh
movp a, @a ;get byte
mov r1, a

mov r0,#000h ; pointer to sprite 0 Y pos in VDC
mov r7, #1
call copyspriteloop
It works good for the first position (029h), but I can't figure out how to advance the correct number in boxydata for it to read it and make the box be in the second position listed (039h) the second time.
Code:
copyspriteloop:
mov a,r1
movp a,@a ; get byte
movx @r0,a
inc r0
inc r1
djnz r7,copyspriteloop
ret


Title: Re: Chris the Cranberry
Post by: Chris! on September 16, 2019, 07:02:32 AM
I figured it out. I needed to add this:
Code:
mov r1,#obstaclenumber
mov a,@r1
mov r3,a
and change that other bit of code to this:
Code:
copyspriteloop2:
mov a,r3
movp a,@a ; get byte
movx @r0,a
ret
So now I might be able to design some rudimentary tracks now. I'd like some ideas for more stuff to put in. I already put in an item that when Chris runs over he gets a short burst of speed (the green arrow thingy.) Thoughts?


Title: Re: Chris the Cranberry
Post by: Chris! on September 18, 2019, 04:07:54 AM
Time for a little update, even though nobody downloaded the previous one. I'm still working on stuff.


Title: Re: Chris the Cranberry
Post by: cjherr on September 18, 2019, 03:30:19 PM
Nice! I like where this is going!


Title: Re: Chris the Cranberry
Post by: Chris! on September 19, 2019, 06:15:12 AM
Thanks!

Can someone with a PAL tv test this latest version? I only have an NTSC TV and an Odyssey 2 so I am wondering if the sprites disappear all the way off the screen when not used because I doubled their height.


Title: Re: Chris the Cranberry
Post by: Chris! on September 19, 2019, 09:48:39 PM
Don't need a PAL tester any more. I recoded it so I don't need to worry.
I also got rid of the title screen "music" and replaced it with a countdown at the start.


Title: Re: Chris the Cranberry
Post by: Chris! on September 20, 2019, 09:51:05 PM
The first track is done.


Title: Re: Chris the Cranberry
Post by: Rafael on September 21, 2019, 04:15:12 PM

Doesn't look too challenging


Title: Re: Chris the Cranberry
Post by: Chris! on September 22, 2019, 03:19:55 AM
Yeah, I know. Perhaps I won't finish this game after all.


Title: Re: Chris the Cranberry
Post by: Nesrocks on September 23, 2019, 10:09:52 PM
I have tested this twice, but I don't think my character is moving. I did start the game and the timer started counting but nothing seems to happen.


Title: Re: Chris the Cranberry
Post by: Chris! on September 30, 2019, 04:33:46 PM
You need to press right to make the cranberry move.