DEMOSCENE THREAD

Your favorite platform ? favorite group ? Oldschool or Newschool ? Post about coding demo effects, music and graphics. Post your favorite demo parts or your own. I will supply you with a bunch of my favorites demos in the following posts. I also know quite a bit about C64 coding, so I could explain some tricks used on it if you'd like that.

Other urls found in this thread:

youtube.com/watch?v=5MexnBunH_g
youtube.com/watch?v=J2Jz1bu2CcA
youtube.com/watch?v=bIM4p0uL6Pw
youtu.be/hvX6Y2bW4Z0
youtu.be/jziQBWQxvok
youtu.be/JvgoWNI698o
youtu.be/9xBahrt8b1I
youtu.be/rWwNgVwQG1A
youtu.be/E0OzX7plbeY
youtu.be/OuA0IBrlUpw
twitter.com/NSFWRedditGif

PLATFORM : Amiga AGA
GROUP : Steroid
NAME : Unexpected (part 1/2)
YEAR : 1995

PLATFORM : Commodore64
GROUP : Reflex
NAME : Mathematica (part 1/3)
YEAR : 1995

Damn, those dot routines look awful when encoded to webm, I should have figured. And the tearing in vertical rasters part is not present on the real thing. It's because the video is not 50FPS. Sorry

PLATFORM : Commodore64
GROUP : Plush
NAME : +H2K (part 2/6)
YEAR : 2000

PLATFORM : Commodore64
GROUP : 64Ever
NAME : Insomnia (part 1&2/5)
YEAR : 2001

I'll write some about C64 coding, because it is nothing like coding on pc, and not just because of the little ram and very slow cpu. C64 coding is all about using the hardware the bad, unintentional way. I'm sure it's also true for other old platforms, but I know only the C64 so deeply. I will tell you about BAD LINES.

What are bad lines? The cpu and video chip (vic) share ram, so they can't use it at the same time. Every 8th line, so the first pixel line of the text line Vic takes the control of the bus to read the screen data. The cpu is idle when this happens. The bad line condition isn't hardwired however. C64 can scroll the image vertically and horizontally, but only by 8 pixels max. The condition for bad line is... the first 4 bits of the line counter have to match the scroll register. Lots of C64 tricks rely on causing bad lines in strategic moments.

If you cause the bad line at the very beginning of the line, Vic will simply read the screen data again. You can change the colours for example, cause the bad line and in resoult you get more colours than just standard 2 in 8x8 character. This technique is called FLI - flexible line interpretation. The second picture in OK uses that.

Another trick requires you to manipulate the scroll register in such a way that there's never a bad line. What happens then ? Vic just doesn't draw anything, only black pixels (and sprites if any). It will continue as soon as it encounters a bad line. With this technique called FLD - flexible line distance - you can move the whole screen downwards without coping single byte of screen data. Unfortunately, it doesn't wrap around the screen, but there's another trick for that

Now imagine what happens when you cause a bad line in the middle of the screen ? Vic suddenly wants to read the ram, but the cpu is using the bus, so Vic has to wait. Of course the raster beam doesn't wait, so when Vic finally starts to paint the image, the beam has already moved to the right and you get shifted image ( and it even wraps around ! ) this technique is called VSP - variable screen positioning. Another, less commonly used name is DNA delay.

DMA delay... sorry

Now you surely noticed the big border around the screen on the C64. It was a common practice on computers and consoles from the 80s, because the visible area of the tv wasn't standardized. To make sure that nothing gets clipped out, they made the actually screen much smaller and the rest is filled with a border. But notice that this demo for example

Draws in the border area. How is that possible ?

Do you remember the scroll register? When you scroll your image to the left or up, there's a blank space left at the right or bottom part of the screen. That's why they made it possible to make the border wider, to hide that empty spot.

Now imagine. You're in the narrow border mode, the bottom border starts at line 260. When you're in wide border mode the border stars at line 252. Now wait until you're past the line 252 and change the border mode to wide mode. Now the trigger for drawing the bottom border is at line 252, but you're already past that, so Vic doesn't draw the border ! It doesn't draw any characters there, it wasn't designed to do that, but it will draw sprites there. Same technique is used to open the sideborder, but this time you have to be cycle exact (because 8 pixels horizontally is one cpu cycle) and you have to do it every line. The demo I pointed to does that on almost all lines with that "normal is boring" banners, impressive, huh ? The first picture in the OP uses the top and bottom border area.

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PLATFORM : Amiga AGA
GROUP : Anadune
NAME : Sunrise (part 2/3)
YEAR : 1996

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Can anyone tell me if there's a _good_ documentary about the demoscene, bonus points if it has scandinavian demogroups.

Yes, there are two that I know, one was made by hungarians, the other is done by finish. I like the hungarian one much better.

youtube.com/watch?v=5MexnBunH_g

youtube.com/watch?v=J2Jz1bu2CcA

Thanks. Been interested in the early Assembly parties held in Helsinki for quite a while now because it's a 40 minute drive from where I live. Too late now to see the actual thing though.

PLATFORM : Amiga OCS
GROUP : Red Sector Inc.
NAME : Mega Demo (part 1/6)
YEAR : 1989

I really enjoy the shit they're still making even today. It is really impressive. What I have always disliked though, is the whole social element. The worshiping of the good/famous groups and people, the greetings list etiquette (almost like friending/unfriending on facebook today), the drama between groups/people, which everyone had to be made aware of.

But if you ignore that, it's cool to see what their coders are capable of.

I don't see it as such, at least not in the C64 scene. Greetz were for the elite and fucking for the lamers, and there's nothing bad about banter. If you don't agree, go make a demo about it, as the saying goes.

Btw, I think that's also my webm, i posted it in other threads hehe.

I just downloaded it from youtube, so I doubt it. Unless you posted it there.

Nah, I didn't. And I see now that yours uses a different capture. Mine is higher quality

PLATFORM : Commodore64
NAME : Dawnfall
GROUP : Oxyron
YEAR : 1995

PLATFORM : Commodore64
GROUP : Oxyron & Crest
NAME : Coma Job
YEAR : 1998

Recorded in debug mode where you can see how the side border is being open in the first part.

oops

What the fuck, I upload the webm but it doesn't appear here

youtube.com/watch?v=bIM4p0uL6Pw
youtu.be/hvX6Y2bW4Z0
youtu.be/jziQBWQxvok
youtu.be/JvgoWNI698o
youtu.be/9xBahrt8b1I
youtu.be/rWwNgVwQG1A

i have too many favourites.

youtu.be/E0OzX7plbeY

I WAS about to post the previous aga demo of theirs, but the quallity would suffer a lot with webm I think. I'll do it anyway. I ran makt on my Amiga and crt tv, looks amazing. I want to get myself C64 finally too, but they are quite expensive, especially with floppy drive and I don't want to use any floppy emulator or cartridge

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NEW JUST DROPPED
youtu.be/OuA0IBrlUpw

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If it comes to c64, just go to the monitor and you can read the source pretty much

Who here hasn't seen BB? It's literally in apt.

LOL, you made my day user.

pretty interesting user, feel free to share more!

was demoscene art drawn with one of those trackball mice? Or a keyboard? I don't think one would've had graphics tablets then, would you?

None of the above.

you could draw sprites with the keyboard by PEEK'ing and POKE'ing the screen memory. At least with the C64. It sounds difficult, but its really not, just very tedious and time consuming. You basically needed a piece of graph paper with your desired sprite drawn in and then to draw it on screen you'd just POKE the appropriate memory value plus the X/Y coordinates of the location

Surely one of your first programs would be a sprite editor!

Most of pictures on C64 is drawn with keyboard and joystick. Nowadays there are cross-platform tools, so you can just do your picture on the PC with is much easier, but a lot of people still do it on the real thing. You can also just use a conversion tool that will generate C64 compatible chars and colorram cells out of any picture, but these are frown upon and are actually easy to spot. The only exception to this rule is when said picture use some crazy graphic mode in which it would be impossible to draw by hand.

First 3 pics with are standard hi-res (2 colors in each 8x8 block)

Multi-Color images (4 colors in each 8x8 block, or 8x4, because the pixels are double wide, 2 colors are common for the whole picture)

Hi-Res or Multi-Color pics with graphics in the border area (only sprites are visible in the border)

Sorry, the turtle is not in the border... my bad
Here are some more

FLI and Interlaced FLI pictures
what is FLI ?


Notice that the turtle pic doesn't have the wide border on the left side. That area is called FLI-BUG and is unavoidable. This pic uses sprites to cover that and do a full-screen (not counting real borders) piccy.

More FLI and IFLI pics

NUFLI pics (FLI pics with sprites underlayed)

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I love that !

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Amiga AGA

Know anything the guys at Shin'en once made?