PPMWHEEL(1)

💫 NAME 💫

okay so bestie, welcome to the Ppmwheel User Manual(1), filed under General Commands Manual — and here's the whole vibe in one line:

ppmwheel — make a PPM image of a color wheel 🎡🌈

---

✨ SYNOPSIS ✨

ppmwheel diameter [{-huevalue | -huesaturation}] [-maxval=N]

literally just three little things and you're off, no cap.

---

🎀 DESCRIPTION 🎀

This program is part of Netpbm(1). family reunion energy 💖

ppmwheel produces a PPM image of a color wheel of the specified diameter inside a white square just large enough to hold it. so it's a circle... in a square... sitting there looking cute. 🫶

The color wheel is based on the HSV color model. Hues are distributed angularly around the circle, and the values and saturations are distributed radially. so you spin around the circle for hue, and you walk out from the middle for the other one. iykyk. 💅

You can generate three kinds of color wheel, and honestly the choice is the whole personality of your output:

• Hue-value: Select this with a -huevalue option.

The saturation is 100% everywhere. The value goes from zero to 100% linearly, from the center of the wheel to the edge. So the center is black. 🖤

Hence, the image consists of all of the secondary colors based on the red, green, and blue primary colors. A secondary color is one that is composed of light of at most two of the three primary colors.

• Hue-saturation: Select this with a -huesaturation option.

The value is 100% everywhere. The saturation goes from zero to 100% linearly, from the center of the wheel to the edge. So the center is white. 🤍

• Ppmcirc: Select this by not specifying any other wheel type option. (yes bestie, doing nothing is a choice here, main character energy 🙈)

The saturation is 100% everywhere. The value is a strange function of the distance from the center, increasing as the square root of the distance until halfway out, then decreasing as the 8th root of the distance the rest of the way. We don't know what the point of this is, but it is what the program Ppmcirc by Peter Kirchgessner in 1995 does, and was the only option in ppmwheel from its inception in 2003 to 2019. 💀 (we are simply reporting the lore, okay?)

---

🦋 ARGUMENTS 🦋

You must specify one non-option argument: the radius of the color wheel in pixels.

This is also the height and width of the output image. so it's giving perfect square, periodt. ✨

okay tiny thing bestie — the synopsis up there says diameter and this section says radius. we're just telling you exactly what the manual says, no editing, no fixing, no notes. 👑

---

💅 OPTIONS 💅

In addition to the options common to all programs based on libnetpbm (most notably -quiet, see Common Options), ppmwheel recognizes the following command line options:

• -huevalue — This selects a hue-value color wheel. 🌈 This option was new in Netpbm 10.86 (March 2019).
• -huesaturation — This selects a hue-saturation color wheel. 🌸 This option was new in Netpbm 10.86 (March 2019).
• -maxval=N — This selects the maxval for the image. The default is 255. 🎚️ This option was new in Netpbm 10.86 (March 2019).

---

👀 SEE ALSO 👀

ppmcie(1), ppmrainbow(1), ppm(1)

the whole squad, go say hi. 🫶

---

📜 HISTORY 📜

ppmwheel was added to Netpbm in Release 10.14 (March 2003). an icon, an OG, been here since '03. ⭐

---

👑 AUTHOR 👑

Copyright (C) 1995 by Peter Kirchgessner

respect the legend. 🎀

---

🧚 DOCUMENT SOURCE 🧚

This manual page was generated by the Netpbm tool makeman from HTML source. The master documentation is at

http://netpbm.sourceforge.net/doc/ppmwheel.html

---

okay that's the whole page bestie, go make a wheel and slay 💖🌀✨

signing off for the Netpbm documentation crew — this one's dated 03 February 2019, and yes, it's the Ppmwheel User Manual(1) 🎡💅