What is new on Andropolis demo?

[Heaven/TQA]

 

the winning demo... I like their Recycle demo more I have to admit...

 

but you c64 guys must be bored like hell with the rotating checkboards?

 

the best part is the imho the rotating rubber rube at the beginning (but seems prerendered) and the kicking ass picture fader where the rotating bar is cutting the two pics...

Edited July 21, 2009 by Heaven/TQA

[pps]

Hey heaven... maybe the wrong forum for that, eh?!?

[Heaven/TQA]

nope...here are Oky, Pete, TMR, Andy...

[PeteD]

hehe yeah, we love our Commie

 

It's full of pretty stuff, yet again but yeah the same pretty things as most demos for a while now. I remember seeing Deus Ex when I first got into c64 stuff again. The last demos I'd seen were back when I was coding in the mid-late 80s. I was blown away, even more hardware tricks, some nice fast routines but even since then nothing has changed much, now it's all about style. If you're going to do the same tricks, make sure it all fits together. This demo for example, from the first thing where the bar wipes across the screen to later where the same thing wipes between two pictures. I like it. But yeah, twisters, roto/zoomers etc are getting a bit boring.

 

 

Pete

[Heaven/TQA]

the rotating bar cutting the 2 pics as fader is my best demo fx for years and reminds me GTA vice city "cutting scene 70" style...

[Heaven/TQA]

btw... the first thing what Graham has coded on A8 was a full screen plasma... you commie guys are so "I want to do no-border"-fx like we are with "sprite overlays"...

 

oh... and TMR first A8 coding was plasma, too...

[PeteD]

hehe but of course C64 guys are going to want to get straight at the A8 palette and what better way than a plasma

[Heaven/TQA]

Pete... I tell you now 2 demo coding secrets... very time critical for

 

- opening the borders... POKE 559,35

- 16 shade mode... POKE 623,64

 

[TMR]

Demos are in part about evolving routines, most of these are fairly clever in that respect:

 

Opening wipe

There appears to be a cycle-timed vertical split in the upper and lower borders where the bar is (changing the background colour) that travels across the screen with the yellow; the screen itself is a high res bitmap copy that has it's attribute data changed as the bar moves across and i suspect the side borders during the screen are being masked by a couple of expanded sprites (one each side).

 

Twisting cube

Pre-calculated for sure, presumably it's using hyperscreen to keep the timings "simple" for the side borders and splitting $d018 to change the data pointers for the twist; it never uses the lowest part of the screen so i'm guessing that's where all the table juggling is taking place and some time has been left free for the loader to work (that's technically "just" a loading part).

 

Zooming chessboard with gaps

i bet that's fiddly... i'm guessing multiple fonts and using a similar $d011 trick to FPD to display everything - i don't think there's any sprite layers involved at least.

 

Rotating wipe

This is scarily complex when you pay serious attention to it; the line is high resolution until it gets too wide for the sprites to handle and is toggled to using horizontal expansion; the difficult bit must have been working out when it was "safe" to transition the picture so that the changes don't poke out of the edges of the bar; all the changes have to happen on an attribute cell by attribute cell basis (meaning it re-writes ten bytes in one pass, eight for the bitmap and two for the attribs).

 

Chessboard rotozoom

Haven't kept up with the state of the art on these, but that does appear to be a particularly tidy example of the genre; i doubt it'd be included if it wasn't doing something different and it's bloody quick considering it's being swung on and off as well...

 

Horizontal picture flip

Now this one i really like and it's being rather sneaky; the picture fades in as a bitmap but switches to characters soon afterwards (using character colour set to black with multi enabled, multicolours and background generating the actual colours in use). Looking at it in VICE with the speed cranked down, it seems to be using about eight frames and relying on the speed of motion and horizontal swing to mask the imperfections.

 

Tile zoomer

Hmm, looking at the scaling i think it's got pre-calculated stages to keep the shading in roughly the right shape; bit like that "infinite picture zoom" effect Booze did in EoD.

 

3D walk-through

It's a complex enough engine to handle stairs and so forth, from what was said on IRC t'other night he has a version that is joystick controlled (well, there can't be room for co-ordinates, it doesn't have very long after that part before the picture upscroller kicks in).

 

Picture upscroller

This one actually worries me slightly... i've done double buffered bitmap scrollers and at a push it's possible to go at a pixel a frame (9K of transfers spread over the first seven frames, then crash dumping the colour RAM on the eighth) but if i'm right it's actually loading in more data during the shift...

Edited July 21, 2009 by TMR

[TMR]

oh... and TMR first A8 coding was plasma, too...

 

Actually, the first thing i did was that high res picture with player underlays, the one that only worked because the emulator didn't show up the issues when using players like that. The second routine i did was a picture with some player overlays, then a Kefrens bar routine... and i have a "real" 240 colour infinite raster bar routine as well! i should release some of this stuff. =-)

[Heaven/TQA]

ah... I can remember that...I made a digi cam pic on real machine for you... the internet radio intro...

 

thanks for the explanation...

[potatohead]

 

I like new 8 bit demos. This one repeated a time or two when it probably would have been better to move on, but is a good production.

 

Love it: "get right at the palette" + plasmas. Hey, where can one get a "plasma for my device for idiots explanation of how those work?"

 

The 3D walker was ok actually. Nice job.

 

My favorite was the image wiper. Excellent!!

[PeteD]

What was that demo recently with the 2 images of the woman, maybe holding a sid chip or something and the picture wiped between the two using some expanding circles? I loved that one.

[Heaven/TQA]

it really kicks ass at 1:54 ff on the youtube video... I never seen that on A8... I not often see this kind of transition fx which are based on the char mem and color ram on a8....

 

I mean it is simple in terms of algorithm... but it looks damned good...

Edited July 21, 2009 by Heaven/TQA

[PeteD]

Like I say, the best demos these days (imho) are the ones with just that bit more style.

[TMR]

What was that demo recently with the 2 images of the woman, maybe holding a sid chip or something and the picture wiped between the two using some expanding circles? I loved that one.

 

Amplifire by Instinct and Horizon, one of the releases from X'08.

[PeteD]

That's the one, ta was driving me mad trying to remember.

[TMR]

Love it: "get right at the palette" + plasmas. Hey, where can one get a "plasma for my device for idiots explanation of how those work?"

 

Depends on the plasma, the one i released wasn't a real plasma as such (actually, i don't think i've done a traditional plasma on the A8 and now i think about it that'd possibly be a fun thing to try with APAC). Here's what i released:

 

 

That's just using the display list to repoint the bitmap once per scanline really, the only "difficult" part was finding the time to update the table of addresses each frame.

[TMR]

Like I say, the best demos these days (imho) are the ones with just that bit more style.

 

i'd not entirely agree with that personally, some of the "battles" over the last few years have led to some phenomenal code that isn't wrapped in any design as such and Crossbow's little productions like Krestage 3 or Don't Meet Crest (which has a fairly unique take on the whole idea of hidden stuff in demos and a notefile as impressive as the demo itself) are great but all-out "coder pr0n".

[PeteD]

Oh yeah, don't get me wrong it's good there are new/better techniques else the whole thing would stagnate. That's why I still love the C64 so much but what I'm not keen on is demos that have 1 clever thing and just show it over and over and over and look we can change a colour on it.

[+Stephen]

The rotating wipe between the 2 pics was awesome.

 

Stephen Anderson

[TMR]

...but what I'm not keen on is demos that have 1 clever thing and just show it over and over and over and look we can change a colour on it.

 

A short burst of something like a chessboard zoom rotator could simply be pre-calculated animations, so longer sequences and changes in the move data (and indeed colours) are used to prove that the code is generating the display on the fly rather than just dumping frames from memory to the screen - the duration of effects in these situations is usually governed by how involved the routine itself is, if it's doing something very impressive or new it gets a bit longer. With some effects it's a case of it being a loading part so the effect has to last longer than the disk or de-crunch operation, the twisting cube at the start of Andropolis for example pops up a couple of times because the demo is loading data during its parts of the intro.

[PeteD]

Sorry fella but you can't tell me what I like in a demo Granted most of the new demos from the top groups have some coderporn, but if I don't like the way its presented then it means nothing to me, as it would mean to anyone who isn't a coder anyway.

[TMR]

Sorry fella but you can't tell me what I like in a demo

 

i'm not trying to, merely pointing out that if they didn't do some of the things you're complaining about the odds are that the style of the demo would be adversely affected elsewhere; running a single effect with a number of presets gives a little more time for "housekeeping" tasks such as loading and decompression, without those repeated moments the overall style of the demo would also be compromised.

 

Take Andropolis for example, the cube at the start comes back a couple times because the demo is loading data simultaneously, if that was just a quick "look, twisty cube - next effect please" there'd be a black screen whilst it loaded that effect which would've been a far more significant dent in the flow.

 

Granted most of the new demos from the top groups have some coderporn, but if I don't like the way its presented then it means nothing to me, as it would mean to anyone who isn't a coder anyway.

 

That sort of goes against what demos are, their primary audience is meant to be coders and it's about showing off; these days if the viewer doesn't understand the code pr0n it's well presented but the design decisions should be about showing off the routines rather than pleasing that secondary audience... they're the people who would've looked at VSP&IK+ and said "nice picture" and missed the point entirely.

[PeteD]

But I still get the feeling you're trying to change my mind about what I personally like

 

You know that I know what you're saying. I'm just saying that I can not like some stuff for whatever reason I want and it matters not one bit to me if every other c64 coder in the world thinks its the bees knees