vtkxform(1)

💖 vtkxform — bestie edition 💖

okay so real talk, this one lives in the The Computational Morphology Toolkit, aka CMTK, and it is so much simpler than it looks. it takes points from a VTK file, yeets them through a coordinate transformation you hand it, and hands you back the glow-up. that's it. that's the whole vibe. 🦋

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✨ NAME ✨

vtkxform — applies a coordinate transformation to point coordinates inside a VTK file. no cap, that's literally its entire job description. 💅

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🌸 SYNOPSIS 🌸

vtkxform XformList

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🎀 DESCRIPTION 🎀

okay so here's the tea. vtkxform reads an ASCII-format VTK file from standard input (yes, stdin, the classic), and then it takes the coordinate transformation you gave it — which can optionally be inverted, if that's the mood — and applies it to the vertex coordinates.

then it writes a VTK file with the transformed points out to standard output, and honestly? iconic. point in, transformed point out. the circle of life. 🧚

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👑 OPTIONS 👑

💜 Global Toolkit Options (these are shared by all CMTK tools)

bestie these are the family options, every CMTK tool has them, they're basically the group chat you're in with all your sibling utilities. 💖

• --help — writes the list of basic command line options to standard output.
• --help-all — writes the complete list, basic AND advanced, to standard output. the full lore drop.
• --wiki — writes the list of command line options to standard output in MediaWiki markup. wiki girlies rise 🫶
• --man — writes the man page source in 'nroff' markup to standard output.
• --version — writes the toolkit version to standard output.
• --echo — writes the current command line to standard output. so you can see what you just did. receipts. 🧾
• --verbose-level <integer> — sets the verbosity level. pick your own adventure, numerically.
• --verbose, -v — increments the verbosity level by 1. heads up though, it's deprecated — it's only still here for backward compatibility. it's giving legacy. 💀
• --threads <integer> — sets the maximum number of parallel threads (for POSIX threads and OpenMP). go fast, but responsibly. 🔥

🌈 Main Options

the actual ✨main character✨ options, the ones that decide what happens to your points:

• --inversion-tolerance <double> — the numerical tolerance of B-spline inversion, measured in mm. here's the trade-off bestie, listen close: smaller values = more accurate inversion, but they may also increase the failure rate. it's giving risk/reward. [Default: 0.001]
• --source-image <string> — sets the source image of the transformation, meaning the image that the transformation maps points FROM. you use this to correct for differences in orientation and coordinate space. [Default: NONE]
• --target-image <string> — sets the target image of the transformation, meaning the image that the transformation maps points TO. same deal, corrects for differences in orientation and coordinate space. [Default: NONE]

🫶 friendly reminder from the source material: source = FROM, target = TO. pls don't swap them, i'm begging, it will not go the way you want.

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⭐ AUTHORS ⭐

Torsten Rohlfing, with contributions from Michael P. Hasak, Greg Jefferis, Calvin R. Maurer, Daniel B. Russakoff, and Yaroslav Halchenko. an absolute squad. 👑

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💅 LICENSE 💅

http://www.fsf.org/licensing/licenses/gpl.html

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🙈 BUGS 🙈

report bugs at http://nitrc.org/projects/cmtk/ — pls do, we're not mad, we're just disappointed. jk, we'd genuinely love to know. 💖

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🌟 ACKNOWLEDGMENTS 🌟

CMTK is developed with support from the NIAAA under Grant AA021697, National Consortium on Alcohol and Neurodevelopment in Adolescence (N-CANDA): Data Integration Component. From April 2009 through September 2011, CMTK development and maintenance was supported by the NIBIB under Grant EB008381. funding lore, we love to see it. 🎀

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and that's the whole page bestie!! CMTK 3.3.1p2, dated Jun 24 2026, filed under vtkxform(1) — now go transform some points and slay 💅✨🦋