New Atari Lynx demo released - Jitter by Desire

[Heaven/TQA]

the cube part renderes into a sprite which then gets put on screen (3 sprites... 4x, 2x and 1x) to get the desired effect. so no palette is touched. so in theory I have no idea what causes the glitch except that rendering those 3 sprites take more time than 60 Hz?

 

and yeah. no double buffer if I remember correct as speedcode takes too much memory.

Edited November 14, 2016 by Heaven/TQA

[+karri]

I believe there is two different problems.

 

1) The palette effect causes Lynx I to turn to a black screen when the sequence with the ape starts.

2) The cube part crashes on Lynx 2 and I have no idea ow why.

 

The lack of double buffer explains the visual effects on the cube scene but not the reason of the crash.

 

What I would like to try out is the code without the fade before the apes to see if Lynx would also crash. Now the Lynx I goes on to the end with a black screen from the starting of the apes to the starting of the credits. Would it also crash if it was drawing the cubes?

[Heaven/TQA]

standalone version... nothing changed to the release... so no palette changes (that's why its green).

 

does this work without glitches?

cube3.zip

[sage]

your irc vectors and the vbl flag share the same memory location?

[Heaven/TQA]

Do they? I guess not...

[+karri]

The Lynx 1 did just show a black screen.

The Lynx 2 showed a huge white rectangle that rotated on a black screen.

Mednafen showed 3 green squares rotating.

 

No crashes.

 

I created a lnx file as I could not find my upload cable.

base.zip

[Heaven/TQA]

But if so one thing which as well drive me nuts is this ZP Makro Auto incrementing ZP Location... Never new why you need such Makro in assembler.

[Heaven/TQA]

Karri that's mainly (assume here) because I don't unit the chipset (see source) but another example that emus are far behind what other platforms offer in terms of accuracy.

[+karri]

Yes, of course. I used my own 52 byte bootloader that does not initialize Suzy or Mikey. With a stock downloader showing a title picture you have some colours already.

 

Here is a small whipped up o-file 2 lnx-file recipe.

 

 

head --bytes=271 nothing.lnx > base.lnx
head --bytes=6 cube3.o > hdr.bll
tail --bytes=3 hdr.bll | head --bytes=1 >> base.lnx
tail --bytes=4 hdr.bll | head --bytes=1 >> base.lnx
tail --bytes=1 hdr.bll | head --bytes=1 >> base.lnx
tail --bytes=2 hdr.bll | head --bytes=1 >> base.lnx
size=`stat --printf="%s" cube3.o`
data=$(expr $size - 10)
tail --bytes=$data cube3.o >> base.lnx

 

The "nothing.lnx" file is any recent cart produced with cc65.

 

I created it from this:

 

#include <stdio.h>
 
void main() {}

 

 

cl65 -t lynx -o nothing.lnx main.c

Edited November 14, 2016 by karri

[sage]

But if so one thing which as well drive me nuts is this ZP Makro Auto incrementing ZP Location... Never new why you need such Makro in assembler.

 

Matter of taste.

But mixing fixed addresses together with ZP macros is definitely a bad idea...

 

The overlap, well If I check your code you assign them the same offset!?

 

.o to .lyx:

 

http://lynxdev.atari.org/lynx/blog/o2lyx_hack.xhtml

Edited November 14, 2016 by sage

[Stun Runner 87]

How can I get this on cart?

Very good 3-D effect.

?

Edited November 15, 2016 by Stun Runner 87

[Heaven/TQA]

Yeah bad idea but most of the BSS include files use that and on c64, a8 you use fixed ones. So reusing code gives some trouble

[Heaven/TQA]

 

better recording with OpenEMU/Monosnap on OSX.

[Level42]

The Lynx 1 did just show a black screen.

The Lynx 2 showed a huge white rectangle that rotated on a black screen.

Mednafen showed 3 green squares rotating.

 

No crashes.

 

I created a lnx file as I could not find my upload cable.

 

What is this file ? I get a blank screen... ?

[+karri]

We were debugging why the rotating cube fails on the real hardware in some cases. On a Lynx I you really get a blank screen instead of a rotating set of cubes. So the best way is to enjoy this on an emulator.

[Level42]

The cubes work fine on my Lynx I but is does show some flickering at the top but I thought that might be the McWill,screen ?

[Level42]

Video....

[Level42]

Next try......

 

 

[Heaven/TQA]

the flickering has nothing to do with hardware failure etc... its simply my code which runs a little bit slower on real hw than in emu and seems not be in sync on real HW so don't worry...

[Heaven/TQA]

the cube is rendering without using double buffer.

[SlidellMan]

Your demos are quite impressive. Now if only you guys made a Lynx game with your 65c02 Assembly skills...

[Heaven/TQA]

It looks that it shares same skills but coding a game is something complete different imho.

 

Demo is a predictable environment for coder while game depends on the player.

 

Then it's not only about gfx music and code but about fun.... and that's something which needs talent