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Hacking Hi-Def Graphics and Camerawork Into 4Kb
TRNick writes "The old home-computing art of hacking elaborate graphics and camerawork into tiny amounts of memory has been lost, right? Not so. The demoscene is keeping ingenious coding skills alive, and TechRadar finds out the latest developments. Winner of the 4kb competition at 2009's Breakpoint party was RGBA's demo 'Elevated,' a gorgeous scrolling demo featuring photo realistic landscapes and music, which fits into the memory used by one of your PC's desktop icons. This is really impressive stuff."
If you're not going to read the article, maybe you should at least have some idea of what the demo scene is about before rushing to first post.
What it is saying is that the executable file is 4096 bytes. The source code has little relation to that. If the program asks to use more memory beyond that after it's loaded, that's fine.
The source is much larger. The size counted is the size of the executable. Write as many comments as you like in your source code.
You can use as much memory as you like, but it's a very boring pile of memory if you don't then precompute a pile of pretty pictures using algorithms and data, which is what the 4kb is really counting.
You can use as many external libraries you like, as long as they're public; so you don't have to write your own OpenGL implementation, but you can't hide 200kb of your latest cool code somewhere other than the 4kb executable.
Feel free to hack the executable format to remove unnecessary headers and sections that an average compiler or linker would generate.
Does my bum look big in this?
It takes a 64MB avi to store the 4KB demo!
The compression techniques in demo code drive AV products nuts, that's just the way it is. They're not going to infect your system -- that would add too much bloat.
Shame it doesn't work on Win7 64-bit tho.
Funny is 4 KB app manages to do HDTV and your AV solution being thousands (if not millions) times bigger can't figure the difference between a trojan and packed executable. That is in case it is even packed.
Try .kkrieger -- FPS game in 96kB
I strongly suspect my video card won't be up to this, so I seeked out a capture of it on youtube:
http://www.youtube.com/watch?v=_YWMGuh15nE
Try Left 4K Dead
The fact is that cramming a lot of game into a small space is still worth doing.
The loaders they use to uncompress the image are routinly also used by virus writers for their own non-3d distructive payloads. Sometimes the people adding the virus signatures get lazy and just target the loader rather than the payload.
I'm just happy these demos run with DEP enabled.
Everyone going on here about how stupid it is that they used existing libraries mind you that typical compo rules state that it must run on a base install. Nobody here is linking to myuberleetcode.dll or anything. That and think about the freaking sound for a second or better yet try and write a 4k and then come back and talk about how stupid it is
Yes, and that'd be very neat and much much harder than you seem to think. Try it, go looking for that magical random seed that creates a 1MB blob of code that does something impressive. Maybe you should expand your idea to first generate a filtering program that can determine if a code sequence, when run over some data, creates a demo? :-)
4K demos are sort of an artistic exploration of Kolmogorov complexity.
Remember also that, if the judges die of old age before your demo appear, you're unlikely to place well in the compo.
Belief is the currency of delusion.
While demos like this are extremely neat, there are also some real limitations to what you can do. This is by no means an all inclusive list but some of the major limitations of making something like this:
1) All graphics are completely procedural, as in mathematically described. That means you don't get to have an artist sit down and draw them. Puts limits on how they can look and demands a fair bit of self similarity.
2) You use a MASSIVE amount of memory in relation to your file size. You may have noticed it sits at a black screen for a bit before running. Why? It is doing all its calculations, decompressing in to memory. When running on my system, it took 350MB. Rather than storing lots on disk and streaming as needed, you store little on disk and have to use tons of RAM.
3) You can't have things like voices and such in the game, takes too much space. Even with extremely efficient compression (which produces audible artifacts) voices will quickly make your game larger.
4) All assembly coding. To do this, you are writing everything as efficient as you can. That's wonderful, but hard to maintain. For a large project that is going to need to run on a lot of systems, be patched and so on, you want a higher level language. Doing everything in assembly would be a nightmare to maintain.
I could go on, this is just an example. What it comes down to is that this is neat for demos. I -love- stuff like this, Farbrausch is one of my favourties for this sort of thing. However it is not a realistic exercise for normal applications. You do not want to sacrifice everything just to try and have a small program footprint. On the contrary, if increasing the on disk size makes it better or more efficient, then you want to do that. Disk space is extremely cheap. Better to use more of it than to sacrifice in another area.
No, it just raises the bar. Back when all you had to work with was CGA in 320x200 it was impressive to show a rotating cube in 4k. Today, this demo nicely shows where the virtual bar is when even considering making a 4k demo. As you couldn't do "Elevated" on your 100 MHz 486 in *no* condition or with any libraries, so would you be laughed at if you presented a rotating cube or a wormhole today.
Here's an excerpt from TFA:
If you can do better, show your work :)
-- Sig down
You need d3dx9_33.dll, which is not included on 64 bit systems.
With that DLL it works fine on XP x64.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Torrent anyone ?
Hi guys. I'm one of the programmers behind Elevated, Inigo Quilez. I was responsible for the programing of the visuals. Christian Ronde made the music and Rune Stubbe made the synthetizer and music player.
Apparently some people cannot believe this, but I will say it myself so there is no more useless speculation going on: this is a 4096 bytes executable demo. Not 4096 of source code. ItÂs a 4096 bytes executable (actually, a few less bytes), x86 binary, with plays a realtime animation and music demonstration without using any external data file. It uses a few d3d functions to generate a rectangle, to compile a hlsl shader and to set a projection matrix. That's it. I have read some people claiming there is "3d engines" built in in directx; I must presume those were assertions coming from people who actually know little about computer graphics today. Also, obviously, Microsoft didn't make any RenderCool( D3DX_MOUNTAINS, D3DX_PLEASE ) function in any of their APIs nor LoadTerabytesOfTextures( D3DX_ROCK_AND_SNOW, D3DX_FROM_HIDDEN_SYSTEM_FOLDER );
The demo doesn't use any external library for sound or whatever. The demo could be recompiled in OpenGL/Linux very easily (it was Opengl in fact, just ported to DX in the last minute), and be something around 4300 bytes. We went for DX to fit in 4096 bytes to complain with the competition rules of Breakpoint, the party where we presented Elevated.
Regarding the music, the demo not only encodes the music track, but also implements the instrument synthesis and track playback. The complete sound system takes about 900 of the 4096 bytes, it's mainly FPU code. To see how this is possible, you can have a look for now to sound synthesis and DSP.
The "textures" are infinite, just as the terrain itself. You can travel as far as you want on the terrain, this never ends, and same for textures. The rock, vegetation, snow, texturing takes about 100 bytes, although it uses some Perlin noise functions that take about 350 bytes. So in essence, we encoded mega, tera, peta and hexabytes of texture in few hundred bytes. The prize, of course, is that they are just too fractalish. But it made the job. Cameras are based on simple sinus and cosinus functions, the playback code is 150 bytes or so, and the camera data itself is exactly 4 bytes for each shot (a 16 bit random seed to feed the sin/cos functions with random frequencies and phases), a velocity and a FOV value. The rest of the sequencing data and playback code (to fade in, fade out, summer/winter transitions, brightness/contrast and color correction parameters) are around 400 bytes. The rendering is done in a "deferred" way, for those who know about computer graphics a little bit, which means the zbuffer if filled first and then a full-screen rectangle is drawn with a shader invocation. This shader computes the surface normals, does the texturing (lakes and sky included) and then does some tonemaping and motion blur. The shader is huge, around 1500 bytes. Another 800 bytes are used for basic operations as opening a window, initializing the rendering surface, sending the synthetized sound to the sound card, implementing the rendering loop and listening for the ESC keypress.
All this code is written in assembler (nasm), for those who were saying we donÂt know what hardware means. We spoke to the machine in this demo, as much as you can do in a modern OS at least from user code. The C version of the demo (which we used during development and debugging) is close to the 4200 bytes. The demo is also selfcompressed, and in fact the first thing the demo does at runtime is to allocate some memory (350 megas), self decompress there, and ask windows to run from that memory location. The uncompressed demo as it comes from visual studio (cl+nasm) is 7 kilobytes if I remember well.
Making a full selfcontained 4 minutes audiovisual piece like this is possible if you know computers, progaming, maths, rendering technologies, you apply a bit of imagination, and you are lucky to be the first to do it. So, those who