Build

In PowerShell, to build:

cargo build --release

Run

To run:

.\target\release\ray-tracing.exe --image-width=400 --aspect-ratio="16,9" --samples-per-pixel=10 --max-depth=50 --out-file="img/a.ppm"

To profile the running time:

Measure-Command { .\target\release\ray-tracing.exe --image-width=400 --aspect-ratio="16,9" --samples-per-pixel=10 --max-depth=50 --out-file="img/a.ppm" }

Example run

On my machine, to generate the image at the end of the book,

Days              : 0
Hours             : 0
Minutes           : 33
Seconds           : 14
Milliseconds      : 344
Ticks             : 19943446029
TotalDays         : 0.0230826921631944
TotalHours        : 0.553984611916667
TotalMinutes      : 33.239076715
TotalSeconds      : 1994.3446029
TotalMilliseconds : 1994344.6029

Misc

To convert a PPM to a PNG:

magick. img\a.ppm a.png

For some reason, using a path like img\a.png makes the command fail with an error about "improper image headers".

To diff two PPM files:

fc.exe img\a.ppm img\b.ppm

The output will be something like:

Comparing files .\IMG\a.ppm and .\IMG\b.ppm
FC: no differences encountered

TODO:

• Profile code w/ flame graph and determine bottlenecks. The flamegraph SVG has text that is cut off. Try the text output instead. Maybe the random number generation is the bottleneck after adding buffered writes?
• Add a CameraOptions struct to simplify the process of initializing a camera. Right now there's a fairly long list of params to Camera::new().
• Figure out the improper image header issue with ImageMagick.
• GPU rendering!

Obsolete

This section is preserves some solutions to problems I faced earlier.

If the binary is set up to write pixels to stdout, then to run, don't run this

# .\target\release\ray-tracing.exe <-- BAD, don't do this. It sets the encoding to UTF-16

See here for details. Instead, do this:

.\target\release\ray-tracing.exe | Set-Content img\a.ppm -encoding String