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Built-in resource editor with themes

Edit the X RESOURCE_MANAGER from inside macXserver. Theme switching, line-numbered code editor, reload without restart.

Built-in resource editor with themes
The Resources editor inside macXserver Preferences. The quickplot theme drives Motif widget colors, menu bar accents, and dialog chrome. Reload republishes RESOURCE_MANAGER to the next-launched X clients.

What it does

macXserver ships a built-in editor for the X RESOURCE_MANAGER property — the global string of resource directives that Motif, CDE, and Xt-based widgets read when they decide what they should look like. The editor has theme switching, a dark code-editor surface with line numbers, “Reload from Disk” to pick up changes you made in another editor, and “Revert to Defaults” with a backup-first safety net.

When you reload, macXserver republishes the new resources on the root window. Newly-launched X clients pick up the changes immediately. Already-running clients keep their original resources (Motif and Xt cache the database at client startup; that’s an X convention, not a macXserver choice).

Why it matters

A vintage Motif app’s appearance is almost entirely a function of what RESOURCE_MANAGER tells it. With no curation, Motif’s defaults are the era-correct gray-on-gray look from 1995 — not necessarily what reads cleanly next to a 2026 Mac desktop. The traditional path to customize this is to write an .Xdefaults file by hand, with X11-specific resource-line syntax and naming conventions that take some learning.

macXserver curates a default theme that looks reasonable out of the box, and the editor makes it easy to tweak. Pick the named theme that suits the app you’re running (the quickplot theme is tuned for the NASA plotting app; the default theme is tuned for the broader Motif and dt-app family), then customize the colors, fonts, and menu styling without leaving the app.

Technical detail

Resources are tiered. The editor surfaces all three tiers:

  1. Built-in defaults. Compiled into the binary. The “Revert to Defaults” button restores these.
  2. User file. ~/.macxserver-resources. Overrides the built-in defaults. This is what the editor reads and writes.
  3. Live overrides via the Preferences UI. Theme switching, font preferences, and a handful of other knobs that change the published RESOURCE_MANAGER content directly.

The file format is X11 resource syntax: widgetClass*resourceName: value per line, comments with !. A [section] block within the file lets you scope a group of resources to a named theme; switching the active theme in Preferences picks which section gets published. There’s a [global] section for resources that apply across themes, and a [macxserver-config] section for macXserver-specific tunables (like the Motif frame chrome).

The editor uses a SwiftUI text view inside an NSPanel with a plain NSView line-number gutter and scroll synchronization. Editing is plain text; the goal is “edit the X11 resource file with a real code editor” rather than “build a graphical resource designer.”

  • The user-editable resources file plus the editor window shipped on Day 19.
  • Tier 1 curated Motif widget-class font defaults shipped on Day 14.
  • The classic-quickplot color palette landed on Day 16.
  • Motif frame chrome configurable from ~/.macxserver-resources since Day 23.