I wrote a Raytracer for DOS, 16 VGA colors

In this tool-assisted education video I create a raytracer from scratch.
The raytracer renders in 16-color VGA palette at 640x480 resolution.

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Homepage: https://iki.fi/bisqwit/

Source code:
‣ https://bisqwit.iki.fi/jkp/raytrace.cpp (only compiles in Borland C++ 3.1 and runs in DOS; this is verbatim the program that I wrote in this video)
‣ https://bisqwit.iki.fi/jkp/raytrace2.cpp (runs on most OSes, uses OpenMP thread-parallelism)
‣ https://bisqwit.iki.fi/jkp/raytrace3.cpp (runs on most OSes, uses CUDA for GPU parallelism, depends on this header file: https://bisqwit.iki.fi/jkp/helper_cuda.h)

List of programs written by me that made this video possible:
- ADLMIDI (This plays MIDI files through OPL3 emulation)
- JAINPUT (Japanese input editor)
- E.EXE (Full-screen DOS editor)
- SPCPLAY (This plays SPC files, which are SNES music), however see below
- New.php (With this I architected how exactly to input the code, where to resize the screen and where to scroll the window etc.)
- INPUTTER (This tool ensured that the plan is followed perfectly, given the time constraints)
- SPCtoMIDI (This converts log files created by SPCPLAY into MIDI files)
- Firstframe.php (This rendered the various effects at 11:10 to 11:54 , after which the real rendered frames were displayed verbatim. The slowness in the beginning was how the BC++ compiled program would have appeared, but it was simulated with this PHP program.)
- Animmerger (This ensured that the frames produced by Firstframe.php were indeed of the EGA palette and dithered the same way as the raytracing was)
- Hudmaker (This converts raw audio and video streams and overlays graphical items, like subtitles, into it, and sends result to encoder)
- Tile4 (This did the four-video inset at the end of the video. I got the idea from Freddy Wong (user:Freddiew).)

List of significant programs involved that were not written by me (all but BC++ are open-source):
- DOSBox and its associated utilities like "mount"
- FreeDOS command prompt
- Borland C++ compiler, Turbo Assembler, Turbo Link
- SNES9x (I used portions of SNES9x in SPCPLAY)
- MEncoder (Video+Audio Encoder; The video recorded by DOSBox was of varying FPS and of varying resolution, due to all the screenmode changes. With MEncoder I resampled them all into a common format, which was 3200x2400 120-fps RGB16 raw video.)
- Lzop (I compressed raw video streams with this for intermediate storage)
- GCC, GNU assembler, GNU gold (After verifying that the program _works_ on BC++, I compiled the _actual_ raytracer with this and did the actual rendering on a multicore Linux server, because raytracing is, well, quite slow)
- Imagemagick (This converted 16-bit PNGs into 8-bit ones)
- Audacity (I mixed audio tracks together with this tool)
- Sox (I may have used it to convert WAV from/to RAW)
- X264 (Video Encoder, used for the final encoding)
- Oggenc (Audio Encoder, used for the final encoding)
- MKVmerge (Video+Audio Multiplexer, used for the final encoding)
- HDPMI32 also makes an appearance in this video, but it's a decoy, as is ADLMIDI in this video. The audio produced within DOSBox was discarded, because it was choppy. I recorded and mixed the audio separately.

More source code links:
ADLMIDI: https://bisqwit.iki.fi/source/adlmidi.html
JAINPUT: https://bisqwit.iki.fi/source/jainput.html
Animmerger: https://bisqwit.iki.fi/source/animmerger.html
Hudmaker: https://bisqwit.iki.fi/source/hudmaker.html

Видео I wrote a Raytracer for DOS, 16 VGA colors канала Bisqwit