FED and the Font Editor generations

Architecture and visible surface

The old implementation builds one FED-WINDOW-CLASS in a single-frame window. The window owns the scaled grid, the editable plane, character-box coordinates, a non-mouse cursor, typeout stream, current font and character, and sample string. The default requested window is 700 by 600 pixels and the initial grid scale is 14 host pixels per glyph cell.

The label shows the selected font, character code and glyph, and sample text. At a scale of one the character-box lines are suppressed; below six the grid points are suppressed. Redisplay tracks a changed rectangle so a point edit need not redraw the entire plane.

Selecting a font can use an already bound font, load its QFASL from the font directory, or create a new descriptor after confirmation. Selecting a character copies its current raster and metrics into the edit plane. Merge copies another character into the current plane. Save replaces the selected live character. Font parameters include line spacing, baseline, blinker height, blinker width, and default space width; the character box supplies the current character width and left kern.

The all-font display labels each glyph with the corresponding default-font character, so a non-alphabetic font can be identified by character position. The sample string uses the font under edit. Reflection accepts an axis and rotation turns the glyph right by 90 degrees.

Complete literal keyboard table

The source folds lowercase letters to uppercase and accumulates decimal digits as a numeric argument. The movement keys use that argument, or derive a power-of- two distance from Control/Meta modifier bits when no explicit argument was typed.

Mouse table

The distinction between complementing and setting matters for reconstructing the feel of the editor: a stroke over an already black point erases it. XFED and the later editors change that default.

Files and preservation

The interactive file commands expose KST only. KST was the PDP-10/ITS font interchange format; it is a source-like textual/binary-word representation, not a screenshot of the edit plane. The museum's public CADR font recovery parses KST alongside AST and Alto sources without using a load band.

Exact functional differences from fed.165

XFED's region eraser recurses only through horizontal and vertical neighbors; diagonal contact does not join two regions. Apart from the listed changes, an exact source diff shows the same font/character selection, metrics, merge, save, sample, transform, KST I/O, numeric argument, redisplay, and command structure. The B break command remains present and undocumented by the short Help text.

The most defensible interpretation is therefore “an interaction experiment or variant of old FED.” What X was intended to mean is TODO.

Architecture and layout

The flavor-based src/lmwin/fed.73 is a substantial architectural rewrite. It uses grid, plane, character-box, and layout flavors rather than the old DEFCLASS window. Its frame contains:

• a prompt pane;
• a typeout pane for font displays and Help;
• the main grid/edit pane; and
• a command menu.

The grid still defaults to scale 14 and suppresses grid points below scale six, but it has incremental redisplay degrees and plane-aware redraw. The menu items are exactly Erase, Home, Save, and Draw line.

The draw mode begins in XOR, or flip, mode. Middle-click cycles the raster ALU through ANDCA (erase), XOR (flip), and IOR (draw). This source-level default is easy to miss in a feature list: the first unmodified left stroke can erase existing pixels as well as set blank ones.

Complete literal input table

The handlers establish all of these variants; the source-embedded Help also confirms the Control-R and Control-W QFASL paths. QFASL input loads a compiled font definition; QFASL output dumps the selected symbol value. The Control-Meta-R AL path is source-established but omitted from that short Help, and is read-only. Ordinary KST read and write retain a per-font default pathname.

Features and implementation findings

Font selection displays the font after choosing it, and can create a descriptor for an absent name. Save updates both the descriptor and the live display font. It warns when the character box is incompatible with the font's height or baseline and when pixels would be clipped outside the stored vertical range.

Display font marks each position using the default character and uses the edited version of the current character. Sample renders a chosen string. Draw line is exposed through the menu. A spline-drawing function is present in the source but is not installed in either the literal keyboard table or the menu; it is a source-visible dormant capability, not an advertised command.

The tracked, non-evaluating Help recovery preserves the public source strings for this generation in lmwin/fed.73.help.lisp, with the old FED and XFED Help beside it. These are implementation help strings, not a substitute for observing a runnable System 46 build.

Provenance and system status

The maintained LM-3 tree at check-in 4df393c declares FONT-UTILITIES as a normal component but FED as optional software loadable by the user. Its FED system reads the font definitions and loads image tools, font conversion, and the window implementation. The program is also registered on system key F with the label Font Edit.

The source file is a maintained composite, not an untouched release artifact. Its header attributes “vanilla FED” to Richard Stallman and calls that portion public domain, while later sections say they were copied from a Release 3 file in October 1986 and other sections add frame-grabber facilities. The narrow header statement is not treated here as a license for every line in the composite.

Full frame and data model

The standard frame is full-screen and contains, from top to bottom, a command menu, main raster grid, a label/sample pane, a row of six explicitly declared register panes, and a prompt pane. The source also carries a register-count calculation bounded from two to eight, but no call site connects it to the six declared panes; dynamic register-count behavior is therefore not claimed. Register display scale decreases for taller fonts so the row cannot consume the whole frame.

The main grid has two one-bit planes:

• the black plane, which is the editable glyph saved into the font; and
• the gray plane, a movable reference or merge source.

The label contains mouse-sensitive font, character, character-code, line-height, baseline, blinker-height, blinker-width, width, and sample-string fields. An asterisk beside the character code marks unsaved raster changes. The sample and all-font display use the edited raster even before it is stored: a global list of FED windows tracks which font/character each window is editing. The same tracking warns when another FED window is editing a target character.

Complete standard command menu

Optional frame-grabber menu

If the color subsystem exists, the frame selects an extended configuration with a threshold slider and medium-resolution color-screen support. It adds:

This configuration is conditional on runtime color hardware support. The museum's monochrome System 303 harness did not reach FED, so none of these frame-grabber operations has runtime confirmation here.

Drawing, transformations, and registers

The main pane starts in Latch mode. Left-drag draws the inverse of the first cell encountered for the duration of the stroke. Middle-click cycles Latch, Draw, Erase, and Flip; right-drag moves a character-box edge; a right double-click opens the system menu. Lines and splines use the current draw mode, except Latch behaves as draw for those shape commands.

Stretch accepts separate integer numerator and denominator values for X and Y. Reflection offers horizontal, vertical, and both diagonal axes. The gray-plane merge operations are:

• copy gray as the new black plane;
• set every black bit corresponding to a gray bit;
• clear every corresponding black bit; or
• flip every corresponding black bit.

Each register stores a raster plus its character-box geometry. Left-click saves black into the register; middle-click replaces black with the register; and right-click opens this complete operation set: clear register, save black, save gray, restore to black, copy to black or gray, set bits in black or gray, clear bits in black or gray, and flip bits in black or gray.

Complete literal keyboard table

There are two sequential X entries in the source table. Setup writes them in order into the same array, so static analysis indicates the later Exchange Planes entry shadows Set X. The embedded keyboard Help also calls X exchange, although another Help passage still discusses X and Y as coordinate setters. Because the optional system could not be loaded, the actual built dispatch was not observed. The source-level collision and likely shadowing are established; runtime behavior remains TODO.

Fonts, saving, and files

Font selection can choose a loaded font, load a QFASL found in the font directory, or create a new font. Character selection is by character or octal code. Save compacts the black plane to a character descriptor, retains left kern and advance width, and warns about incompatible height/baseline or pixels that would be lost above or below the stored character region.

The file menu is broader than the keyboard letter suggests:

Again, Save Char changes the selected live font; Files writes a persistent font representation. The implementation maintains separate KST and AST default pathnames where available.

Source findings beyond the embedded Help

• Multiple FED windows share edited-character awareness. All-font and sample output can show an unsaved edit from another FED instead of the installed live glyph.
• Unsaved changes are represented explicitly and shown with an asterisk. The source warns on character changes and cross-window collisions; Help text that says a change is simply lost does not describe every implementation path.
• The frame-grabber configuration is chosen at instantiation time. The source warns against saving a live FED instance in a load band because color and monochrome environments instantiate differently.
• The duplicate X binding is an implementation inconsistency not evident from a clean feature list.

A separate Dynamic Windows implementation

The Genera Font Editor is not the System 303 FED-FRAME source with renamed menus. Its program framework inherits from a reusable bitmap-editor and the Dynamic Windows Help Program. The system declaration classifies Bitmap Editor as a basic, non-advertised system and loads raster-plane support, color helpers, Bitmap Editor, Stipple Editor, and Font Editor serially after the graphic-editing dependency.

The framework is selected by the { system key when loaded and also exports a global Edit Font command. It has two configurations:

• Tall: title, sample, and large grid at left; Help, Undo, draw mode, Draw, Gray, Font, parameter, character, and register panes at right; command interactor below.
• Wide: title, sample, grid, registers, controls, and command interactor stacked horizontally across the wider frame, with menus arranged in columns.

Both contain a scrollable/typeout-capable grid, a 128-entry character pane, accept-values panes for edit and font parameters, a sample pane, and raster registers. The character pane is hard-coded to the first 128 indices; a source comment leaves proper character-set scrolling as unfinished work.

The default state uses character width 10, grid scale 10, baseline height 10, and total height 12. In this specialization only the left and right bounding-box components are draggable. Font height and baseline are changed through the font parameter pane rather than by dragging the top, baseline, or bottom edges.

Font-menu commands

Font names in List Fonts/Show Font output are presentations: selecting one can invoke Edit Font or Show Font without retyping it. A separate presentation translator makes displayed character objects selectable for editing or loading into gray.

Inherited Draw and Gray menus

The Font Editor inherits this complete visible Bitmap Editor menu surface:

Draw Polygon exists as a command but has no menu accelerator, so it is available through the full command interface rather than the visible Draw menu. Flood fails with a command error if the selected region is not closed. Line and spline commands survive from old FED even though the source notes that low glyph resolution limits their usefulness without subsequent pixel editing.

For a normal one-bit font, the drawing-mode pane contains Draw, Erase, and Flip. Bitmap Editor also supports Foreground and Background modes for richer image element types, but those are not additional colors in an ordinary bit font.

Mouse and modifier behavior

Control and Meta are sampled while the mouse is moving, not just when the stroke begins. A user can therefore press or release a modifier during one drag to change its operation. The default source setting suppresses command echo for ordinary point drawing, avoiding a command transcript for every pixel.

Complete explicit keyboard accelerators

The framework inherits general Dynamic Windows command entry and the command interactor. These are the Font Editor's literal single-key accelerators:

There is deliberately no asserted one-key accelerator for Gray Char: a source comment considers G but does not install it. Menu commands without a key remain available from the menu or command interactor.

Character metrics, sample, and save behavior

Genera represents the editable font as a BFD and the selected glyph as a BCD. The character parser understands one literal character, a character-set name, or an octal code within the selected set. Editing a missing position creates a new blank character at the font's default advance.

The sample pane renders the edited glyph in place of each occurrence of the current character, so changes can be judged before Save Char. Its incremental redisplayer remembers only up to 10 pixels of left and top kern around the edited image. That source-visible “magic number” is a preview limitation, not a font-format limit.

Changing font, changing character, or exiting offers to save a modified character. Drawing without a current character triggers a confirmation before proceeding to another selection. Save compacts the occupied raster, records advance width and left kern, and warns before clipping ink outside the vertical font box. The implementation deliberately does not preserve per-character top kern in its save path; vertical alignment comes from the font-wide baseline and height. Font parameters expose height, baseline, blinker width, and blinker height; edit parameters expose the character width and view/bounding-box state.

Undo/redo covers font and character selection, sample and rename changes, loading gray, pixel and shape edits, plane operations, registers, transforms, scale/view changes, and bounding-box manipulation. Writing a file is a persistence action, not an inverse raster edit, and is not represented as an undoable transformation in the inspected source.

Registered file formats

The file commands query a registry rather than hard-coding one menu. The matching Genera 8.5 font I/O source registers:

When a pathname's canonical type names an available operation, the Font Editor uses it automatically; otherwise it prompts from only the formats that implement the requested read or write side. The conversion routines normalize older font descriptors into BFDs for editing.

Manual, source, and release differences

The licensed media includes five Sage binary files titled Font Editor. Their 83 records cover concepts, entry and exit, drawing, gray plane, registers, transformations, files, parameters, and mouse sensitivities. The document's own front matter identifies Release 6.0, while these installed binaries were compiled on 25 August 1993 under system version 451 and Sage 439. They are valuable intended-use evidence but are not assumed to be a complete Genera 8.5 behavioral specification.

Two examples show why the implementation was audited independently:

• the manual presents the user workflow, but the source establishes the hard- coded 128-character pane and 10-pixel sample-preview kern limit; and
• the source exposes Draw Polygon through command entry without a visible menu accelerator and considers, but does not bind, a G accelerator for Gray Char.

The manual payload remains ignored under build/help/genera/ and is not linked from publishable documentation. The tracked Genera Help extraction note describes how to reproduce the local decode without distributing the prose.

System 303-0

The isolated CADR session d30-fed-cadr-20260718, generation 1, ran from 08:14:54 to 08:19:14 EDT on 18 July 2026. The base and private disk began as SHA-256 bb16e46ad81decfe1efe691d36b6aa4ce3fd4ffb82474365de3520989d397cb5. The pinned public system source was 4df393c, the private copy matched it, and the executed usim SHA-256 was 707a77d23e28ea1c45ae0eb0145dc181fa7ba649b9defc30044d4f847ac2c5be.

Calling FED by package name reported an undefined function because the optional system was not resident. (make-system 'fed :noconfirm) then tried to retrieve its configured source/binaries from AMS-BRIDGE-1 and stopped with “Host not responding.” The harness intentionally supplies no guest-visible file service. This proves that the editor is absent from this band and that its configured load path needs a file server; it does not prove that the FED implementation itself fails.

The session stopped cleanly (forced_stop: false, state_may_be_incomplete: false), both emulator and Xvfb exited with status zero, and the base disk was unchanged. Raw captures show only the listener and load error. They are not application evidence and were not selected for publication.

Screenshot TODO: build or obtain a rights-clear System 303 band with the optional FED system already loaded, or provide the configured source tree through a research file service, then capture the standard FED frame, gray-plane merge, register menu, and—only if the required color subsystem can be reproduced— the extended frame-grabber configuration.

Genera 8.5

The clean Genera attempt is generation 3 of d30-font-editor-genera-20260718, from 08:31:16 to 08:33:01 EDT on 18 July 2026. It used the licensed 54,804,480-byte Genera-8-5.vlod, SHA-256 a8ee5e86cc7e322f7385af3e0cd579d7650d4dcfc3ce328acbf8b25515dd0672, and VLM SHA-256 9f5e18d5770f973879716182b6856ef5a8ee9d3b2bb907476ea0cf35986aa4c7. The action log records Select plus {, followed by direct command input Edit Font.

The Select gesture left the cold listener unchanged and the direct command was reported as not a command name. Static source establishes that { and Edit Font are registered when the Bitmap Editor system is loaded, so the bounded runtime conclusion is that the application was not loaded into this cold base world. No attempt was made to broaden the isolated guest with a Symbolics site or file service merely to satisfy this page.

The action log has four intent/outcome records and SHA-256 b7299b03e8e8799b9bc3e60b57fc54fc2c16d350700f179525b09c51c317c09a. Shutdown reached the prompt, accepted confirmation, and made cleanup progress, then encountered the already documented VLM cleanup deadlock and required a bounded forced stop. Accordingly forced_stop and state_may_be_incomplete are true; host shutdown was not orderly. The private and base world hashes remained unchanged. The harness did not invoke Save World or create a process checkpoint, and whether an in-guest save occurred remains unknown rather than inferred from shutdown.

Raw captures show only the unchanged listener and command error. They do not show the Font Editor, add no useful visual evidence to this article, and were not selected for rights review or publication.

Screenshot TODO: in a fresh isolated session, load the licensed Bitmap Editor system through an appropriately configured local Genera site, then capture only the minimum scholarly evidence needed: the initial Font Editor frame, one character with black/gray planes and metrics, one register or transform interaction, and the format chooser. Each image must separately pass the runtime screenshot publication review.

Public MIT and LM-3 source

The System 46 sources are from public commit 8e978d7d1704096a63edd4386a3b8326a2e584af and carry the snapshot's three-clause BSD license. The LM-3 rows match maintained Fossil check-in 4df393c68d7f083ce42d5c377039d26043cc18a9031ace28258dc97f4137eb91.

Licensed Genera implementation and Help

These identities permit local reinspection without publishing the proprietary files or decoded Help. Paths are relative to the purchased release's sys.sct tree.

The installed Font Editor book consists of five Sage binary files:

All five record system version [451,0] and Sage version [439,0]. The decoded copies remain local and ignored. This article paraphrases findings and contains no recovered glyph raster, font file, manual passage, or proprietary source.