PERSPECTIVE(nged)

get or set the view perspective angle

📅 published 7.44.0, from nixpkgs unstable

💅 PERSPECTIVE (nged) — the get/set-your-view-angle page

okay bestie, welcome to perspective(nged), a BRL-CAD User Command and honestly one of the most underrated little glow-ups in your mged toolbox ✨

🌸 SYNOPSIS 🌸

perspective
perspective angle

that's it. two modes. no cap. 🎀

💖 DESCRIPTION 💖

the perspective command gets or sets the perspective (field-of-view) angle for the current view. literally just vibes control for how much depth your eyeballs get. 🦋

  • no arguments 🫶 — returns the current value of gv_perspective as a floating-point number. a value of 0 (or any value ≤ SMALL_FASTF) means orthographic (parallel) projection, iykyk.
  • one argument, angle 👑 — sets gv_perspective to the given value, in degrees. the behavior depends on the magnitude of the angle:
    • if angle > SMALL_FASTF (i.e. a positive, non-trivial value): a perspective projection matrix is constructed via persp_mat with aspect ratio 1.0, near clip at 0.01, and far clip at 1×10^10. that matrix gets stored in gv_pmat and the view is updated via bv_update. main character energy fr fr 🔥
    • if angle ≤ SMALL_FASTF (zero or negative): the perspective matrix gv_pmat is reset to the identity matrix, effectively switching to orthographic projection. bye bye depth 💀
typical useful perspective angles range from about 15° (narrow, telephoto-like) to 90° (wide, distorted). values above 90° produce strongly distorted views — dramatic, but not cute 🙈. setting the angle to 0 disables perspective entirely.

✨ EXAMPLES ✨

🍓 Example 1. Query the current perspective angle

mged> perspective

returns the current perspective angle, e.g. 0 when orthographic projection is active. a little vibe check for your view 🌈

🧚 Example 2. Enable a standard perspective view

mged> perspective 45

sets the field of view to 45°. objects farther from the viewer will appear smaller relative to nearby objects. the classic. the icon. 💅

⭐ Example 3. Use a narrow telephoto-style perspective

mged> perspective 15

sets a narrow 15° field of view, compressing depth and making distant objects appear proportionally larger. zoom zoom, lowkey obsessed 📸

💜 Example 4. Disable perspective (return to orthographic)

mged> perspective 0

resets gv_pmat to the identity matrix, switching the view back to orthographic (parallel) projection. flat, parallel, and honestly kind of chic. 🎀

👑 AUTHOR 👑

BRL-CAD Team — the devs behind the magic 🫶

😭 BUG REPORTS 😭

reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org. be nice, they're doing their best 💖

and that's the whole page, bestie! this was PERSPECTIVE(nged) from the BRL-CAD User Commands — go forth and set your angles wisely ✨💅🦋

📦 where this page comes from