Search found 665 matches

by leonard
Mon Mar 27, 2017 6:13 pm
Forum: 680x0
Topic: about the blitter ^^
Replies: 27
Views: 21097

Re: Re:

SNES (which was released only one year after A500) was a twice or more better. it's extremly hard to compare the two systems, and even harder with numbers! ( twice or more ). What feature are you speaking? If you speak about CPU power, SNES is more than twice slower than AMIGA :) Of course SNES is ...
by leonard
Mon Mar 27, 2017 6:09 pm
Forum: Coding
Topic: YM : Sample and R13 retrig questions.
Replies: 11
Views: 10196

Re: YM : Sample and R13 retrig questions.

it does not also reset the software envelope too what do you mean by software envelope? You mean square wave generator? To my understanding, the YM works exactly the same on ATARI or CPC. On Atari at least it just reset the volume enveloppe. It does absolutly nothing on the three square wave genera...
by leonard
Sun Mar 26, 2017 5:16 pm
Forum: 680x0
Topic: about the blitter ^^
Replies: 27
Views: 21097

Re: about the blitter ^^

For plain 4 bitplan copy, the blitter is not much faster, true. But for one bitplan things, it's often twice as fast! for instance to display a 1 bitplan background, you will do : move.w (a0)+,offset(a1) this is 4 nops per write on CPU, only 2 with blitter! it's even better to clear one bitplan: 3 t...
by leonard
Fri Mar 24, 2017 5:00 pm
Forum: Hardware
Topic: Dilemma: Mega STE or not Mega STE?
Replies: 41
Views: 12194

Re: Dilemma: Mega STE or not Mega STE?

STe or MegaSTE, the "We Were @" demo ( http://www.pouet.net/prod.php?which=66702 ) will run the same, so you could do whatever you want :)
by leonard
Fri Mar 24, 2017 3:57 pm
Forum: Coding
Topic: YM : Sample and R13 retrig questions.
Replies: 11
Views: 10196

Re: YM : Sample and R13 retrig questions.

So there is a table converting a 8-bit value to 2 (or 3?) 4-bit values. Is there somewhere I can see this table ? - Is the result *really* 8 bits? Shouldn't it be only 5 bits (3 * 4-bit numbers) ? I attached one of these table here. The table layout is specific to please 68000 replay rout so some e...
by leonard
Tue Oct 25, 2016 8:52 pm
Forum: Coding
Topic: Quiz of the week: Single cycle accuracy code.
Replies: 18
Views: 7789

Re: Quiz of the week: Single cycle accuracy code.

Ijor, that's just awesome :) I mean, I have the feeling that I can learn new stuff about ATARI when reading atari forum till the end of my life :) I implemented the strange PSG timing access in SainT using a very empirical rule, and I never suspected the "+1" waitstate. In my wrong brain, it *should...
by leonard
Tue Oct 11, 2016 6:43 pm
Forum: Demos - General
Topic: Cuddly Demos and Fantasia patched
Replies: 19
Views: 32426

Re: Cuddly Demos and Fantasia patched

mikro wrote:If you mean changing amount of pixels in hz/v direction while keeping the ST palette registers then yes, this is possible. :)
really? you mean it's possible to set a 416*272 resolution with 4 bitplans and ST palette? If yes we could imagine a complete falcon port of cuddly demo, right?
by leonard
Mon Oct 10, 2016 12:43 pm
Forum: Demos - General
Topic: Cuddly Demos and Fantasia patched
Replies: 19
Views: 32426

Re: Cuddly Demos and Fantasia patched

The cuddly demo won't work on Falcon, even if you patch it to pass the loader, it requires an STF/STE shifter for all the border tricks, which the Falcon doesn't have (the Videl has a shifter compatible mode, but that's mainly for games/demos not using sync/freq switches to remove borders) Nicolas ...
by leonard
Thu Sep 08, 2016 7:32 pm
Forum: 680x0
Topic: Just another Blitter demo
Replies: 81
Views: 47369

Re: Just another Blitter demo

dml wrote:Oh I didn't manage in person unfortunately (family stuff) - just entered remotely. My entry was the Falcon030 realtime-raytracing 64k thing at the start of the compo.
Oh that was you! Congratulations, I really like that demo and the rendering pattern!
by leonard
Tue Sep 06, 2016 10:37 pm
Forum: 680x0
Topic: Just another Blitter demo
Replies: 81
Views: 47369

Re: Just another Blitter demo

dml wrote:we were both '@' that day on different platforms! :-)
really? sorry I didn't know how you looks like! What platform?
by leonard
Mon Sep 05, 2016 11:58 pm
Forum: 680x0
Topic: Just another Blitter demo
Replies: 81
Views: 47369

Re: Just another Blitter demo

I did a lot of generated blitter code in We Were @ demo, that's cool :) The endmask technic is nice and I play with it a bit in some non released code yet. Previous record seems to be 21 sprites here. Do you think you can do 22 with only end mask line re-ordering?
by leonard
Wed May 25, 2016 12:45 pm
Forum: 680x0
Topic: Just another Blitter demo
Replies: 81
Views: 47369

Re: Just another Blitter demo

Update: a new optimised version now displays 17 Blitter objects: :D This is really nice code! I love sprites record :) I though about exactly the same routine. I didn't write it but it's funny I though about reordering the mask data to use "move.l dn,(a0)+" and "'move.l dn,-(a0)" combined to keep u...
by leonard
Fri May 20, 2016 2:12 pm
Forum: CosmosEx
Topic: MP3 playing on STE - Decoding through the CosmosEx
Replies: 27
Views: 11848

Re: MP3 playing on STE - Decoding through the CosmosEx

nanard wrote:is that the proper init ?
yes, but you should not change bit 6 & 7 of register 7 to keep best compatibility ( not related to sound )

reg7 = (reg7 & 0xc0) | 0x3f;
by leonard
Wed May 18, 2016 9:00 pm
Forum: Coding
Topic: ATARI HDD low level info
Replies: 47
Views: 19164

Re: ATARI HDD low level info

TronicOfEffect wrote:Was a HDD version ever released to the general public? I saw Grazey had a version at Outline last week. Is there a link to download?
simply get latest version from pouet:

http://www.pouet.net/prod.php?which=66702
by leonard
Thu Apr 28, 2016 9:20 am
Forum: CosmosEx
Topic: MP3 playing on STE - Decoding through the CosmosEx
Replies: 27
Views: 11848

Re: MP3 playing on STE - Decoding through the CosmosEx

you do it that way, because a branch is slower when taken, right ?
exactly, 4 cycles win each sample

YM can "simulate" a 8 bits DAC using three 4 bits voices because YM volumes are logarithmic. So you can use small log values to "fine adjust" the global volume.
by leonard
Wed Apr 27, 2016 9:02 pm
Forum: CosmosEx
Topic: MP3 playing on STE - Decoding through the CosmosEx
Replies: 27
Views: 11848

Re: MP3 playing on STE - Decoding through the CosmosEx

prepare ym data on Pi directly tin is right, a very fast STF player is possible, even with more than 8bits sample quality. It requieres to prepare some data on rasp. On the ST side we can use almost 12bits quality YM table. And if you remove any TOS or ROM access in the main player core, we even ca...
by leonard
Tue Apr 26, 2016 11:06 am
Forum: CosmosEx
Topic: MP3 playing on STE - Decoding through the CosmosEx
Replies: 27
Views: 11848

Re: MP3 playing on STE - Decoding through the CosmosEx

that's really cool project! I guess there is many other cool ideas to do with the cosmoex cpu!

I'll have a look at your mediaplayer source code, I guess I can add STF replay compatible!
by leonard
Wed Apr 06, 2016 1:09 pm
Forum: 680x0
Topic: Let's talk about dev tools.
Replies: 12
Views: 7669

Re: Let's talk about dev tools.

qwe wrote:If the kernel can be usefull as a technique to reduce the amount of memory used by a program, where can we find its documentation?
sorry to answer so late... you could find usefull infos in the readme.txt in demosystem folder.
by leonard
Wed Apr 06, 2016 12:06 pm
Forum: Demos
Topic: ATARI ST demos working on Falcon 030. The list.
Replies: 3
Views: 15999

Re: ATARI ST demos working on Falcon 030. The list.

Hi!

Just see that old thread! can I add these two demos:

Amiga Demo 2 ( http://www.pouet.net/prod.php?which=52336 )

Oxygene sprite record ( http://www.pouet.net/prod.php?which=16231 )
by leonard
Fri Apr 01, 2016 9:31 am
Forum: Coding
Topic: ST Chipset decap
Replies: 144
Views: 86368

Re: ST Chipset decap

Below are simulation waveforms for the above circuit (SHIFTER Reload Control). This is awesome! As I'm not an hardware guy at all, I'm really fascinated how people like you can understand and even more "predict" weird shifter effects by just looking at a custom chip :) Now I dream about a new emula...
by leonard
Thu Mar 17, 2016 12:38 pm
Forum: 680x0
Topic: Let's talk about dev tools.
Replies: 12
Views: 7669

Re: Let's talk about dev tools.

Filesystem is a good way to go. But I personaly prefer my own toolchain, generating directly a bootable MSA disk. I already release it with sample. Just run a .BAT and you get the complete MSA disk file containing a demo, ready to use. I don't use vasm but "as68", a 68k assembler by the famous Ziggy...
by leonard
Tue Mar 15, 2016 12:00 pm
Forum: Demos - General
Topic: ATARI Bitmap converter
Replies: 3
Views: 13635

Re: ATARI Bitmap converter

npomarede wrote:I think you somewhat duplicated part of what Troed / sync
Oh I wasn't aware of that tool! Looks really similar. Mine just fit my needs in "We Were @" demo so it has sprite sheet support and "one palette per line" image converter. Obviously I didn't add any AMIGA options :)
by leonard
Mon Mar 14, 2016 10:53 pm
Forum: Demos - General
Topic: ATARI Bitmap converter
Replies: 3
Views: 13635

ATARI Bitmap converter

Hi, Here is a nice tool for demo creation. It's a bitmap converter, with several options. It can read any picture format ( use FreeImage internally ) and produce 1 to 4 bitplans image. Support chunky mode, 16 colors per line with dithering, support sprite sheet, etc. For information that tool was ma...
by leonard
Thu Mar 10, 2016 12:59 pm
Forum: News & Announcements
Topic: ATARI demo nominee in Meteoriks Awars 2015!
Replies: 4
Views: 4482

ATARI demo nominee in Meteoriks Awars 2015!

I'm more than proud to see that "We Were @" demo is nominee in two categories of Meteoriks Awards 2015 ( "Public Choice" and "Best Low End Demo" ) https://2016.meteoriks.org/nominees#nominees-7 https://2016.meteoriks.org/nominees#nominees-8 Please note two others ATARI demo are nominated too! ( by C...
by leonard
Wed Feb 10, 2016 12:12 am
Forum: Demos - General
Topic: We Were @ - wrong colors
Replies: 8
Views: 16892

Re: We Were @ - wrong colors

ggn wrote:What people call surprise... I call a huge 2-week email backlog. With Leonard nearing a nervous breakdown ;).
exactly :)

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