Interview with Demoscener “kb” of Farbrausch

Wow, pretty good. I haven't followed games and the demoscene in the last few years, so modern graphics always impress me a lot.

My favorite demo is Sonnet by Threestate: http://www.pouet.net/prod.php?which=3282

Back in the DOS days, everyone more or less had to write their own rasterizers and write that data directly to the graphics controller (their own graphics driver), which probably took a few KB to do. Modern demos with full GPU acceleration use whichever 3D API/stack the OS provides, which (as a complete guess) is several hundred MB. Even that number pales in comparison to the amounts of data that the procedural generation within some 64k intros produce.

Additionally, many effects in modern demos run purely in shaders, written in HLSL or GLSL. The CPU part draws a single rectangle and the rest happens in a shader. Would you count that as depending on system libraries? Shader languages aren't much more high level than C, so its pretty close to the metal. In any case, you can't go more low level because GPU machine code (which HLSL etc compile down to) is pretty inaccessible in practice.

An OpenGL application that displays a triangle links to these libs:

libc.so.6 libdl.so.2 libdrm.so.2 libgcc_s.so.1 libglapi.so.0 libGL.so.1 libm.so.6 libpthread.so.0 librt.so.1 libSDL2-2.0.so.0 libstdc++.so.6 libX11.so.6 libX11-xcb.so.1 libXau.so.6 libxcb-dri2.so.0 libxcb-dri3.so.0 libxcb-glx.so.0 libxcb-present.so.0 libxcb.so.1 libxcb-sync.so.1 libXdamage.so.1 libXdmcp.so.6 libXext.so.6 libXfixes.so.3 libxshmfence.so.1 libXxf86vm.so.1

Now to be fair, we'll only count those we directly link against:

ibSDL2-2.0.so.0 libstdc++.so.6 libGL.so.1 libdl.so.2 libc.so.6 libgcc_c.so.1 libm.so.6

These few turn out to be the biggest in our bunch, totalling to 5.5MiB.

So there you have it, by linking a minimal graphics demo on Linux, you are implicitly linking to about 5.5MiB of direct system libs and 8.6MiB of indirect system libs. These numbers will vary wildly for other OS, but I guess the DirectX stuff would be larger.

The DOS 64k intros typically didn't link to any stdlib but would just provide their own implementation along with a few of the symbols that the C/C++ compiler (typically Watcom) would require. Combine that with a tiny DOS extender like PMODE/W and a compressor like UPX and you'd be off and running. A minimal intro (just showing a bouncing pixel or whatever) could be had with only just a few kilobytes.

Nowadays intros typically rely on, as mentioned, D3D or OGL but also usually on the MSVC runtimes. Compression is still done using tools like UPX or kkrunchy but that actually's becoming difficult to do because virusscanners are usually flagging them as suspicious nowadays because of all the malware that also uses these compressors. Also, file size is not something that most people care about too much nowadays so the whole concept of the intro seems to have become less and less interesting over the years.