Glyph editor for the Modular Font Editor K project.

MFEKglif mixes three technologies: Skia, a powerful path rasterizer and manipulation library; Dear ImGui, an immediate mode GUI toolkit; and Rust, a modern high-performance systems language.

I wrote it after, hopefully, learning from the mistakes made by George Williams in FontForge, after being a user of FontForge for six years and a co-maintainer for one and a half years.

MFEKglif is the flagship program of the Modular Font Editor K project, which aims to create a full font editor by making many small programs that all work together, fulfilling the Unix adage that each program should have one task and do that task well. MFEKglif aims to do the task of creating and editing glyphs well.

To make this as easy as possible to build, and cross-platform without hassle, resources are compiled into the binary via the Rust include_str! macro, and MFEKglif is statically compiled by default to its C dependencies.

Note: This is a basic list to get you started. A complete list can be found in resources/default_keymap.xml. You may copy this file to e.g. $HOME/.config/MFEK/glif/keybindings.xml on Linux and modify it.

^{_{For more information, see § “I/O Help”.}}

• CtrlO — Open user-specified .glif or .glifjson file
• CtrlS — Save current glyph in a multi-layered .glifjson file
• CtrlShiftS — Save current glyph in a multi-layered user-specified .glifjson file
• CtrlU — Flatten the topmost layer, and write it to a user-specified .glif file
• CtrlShiftU — Flatten the topmost layer, and overwrite current .glif with it
• CtrlE — Export the multi-layered .glif to different glyphs/ directories for each layer, with layerinfo.plist and update layercontents.plist for each.

• A — Select «Pan» tool
• P — Select «Pen» tool
• V — Select «Select» tool
• Z — Select «Zoom» tool
• AltD — Select «Dash Along Path» tool
• AltP — Select «Pattern Along Path» tool
• W — Select «Variable Width Stroke» tool
• M — Select «Measure» tool
• N — Select «Anchors» tool
• S — Select «Shapes» tool

• CtrlA — Select all points in current layer
• Backspace — Delete currently selected points

MFEKglif is still alpha-quality software, and a numbered release hasn't been made yet. Before 1.0 is out, though, you can test it out with the artifacts function in GitHub. Go to «Actions», choose a commit, and download the artifact for your OS. Three are uploaded: MFEKglif-linux, MFEKglif-windows, and MFEKglif-macos (not notarized).

Apple charges a fee to "notarize" applications and without this "notarization" MFEKglif will not run correctly, or in some cases, at all. So, for the foreseeable future, you must build MFEKglif from source on OS X. This is not as hard as it sounds! :-)

• Download and install the Vulkan SDK.

MFEKglif depends on GTK3 (for the open/save dialogs). If using X11 and not Wayland, it depends on the X11 C shape extension (libxcb-shape.so.0) and the xfixes extension (libxcb-xfixes.so.0). Their header files are also needed: /usr/include/xcb/shape.h and /usr/include/xcb/xfixes.h.

On Arch Linux, these two packages provide all the dependencies: gtk3 libxcb

On Ubuntu, these three packages provide the dependencies: libgtk-3-dev libxcb-shape0-dev libxcb-xfixes0-dev

• Download and install rustup, selecting either the nightly or stable toolchain. MFEKglif builds on both as of 7 November 2021.
• Pull this repository, and finally…
• Compile the project. An example command is in § Contributing; you may also find the provided Makefile helpful.

If you previously pulled the repository and get errors related to glifparser, mfek-ipc, or another local unstable dependency, try running cargo update to force Cargo to pull the latest versions from GitHub.

By default, MFEKglif compiles and statically links to SDL2. If you have SDL2 installed, or find compiling it difficult for some reason and wish to link to a binary SDL2, you should provide the flag --no-default-features to cargo build. This will disable the features sdl2/bundled and sdl2/static-link, and your system will attempt to link to a dynamic libSDL2.

It's worth taking a moment to explain MFEKglif's I/O. Before November 6, 2021, a complex system was used to save private MFEKglif UFO .glif extensions to the standard .glif format. This became too confusing, both for users and developers, and was removed.

MFEKglif considers UFO .glif as an import format, and its own native format is .glifjson, which is just a JSON file with keys and values it understands. This is because MFEKglif supports multi-layered glyphs, variable-width stroking, pattern-along-path, and many other features that are of course not in standard .glif; others, such as Spiro and Hyperbézier curves, are planned.

So, when you save (Ctrl+S), MFEKglif will write a file named a.glifjson if you had open a.glif. To get back out UFO .glif output, you have to do one of the several export abilities MFEKglif has. If you instead save with Ctrl+U, you'll be given a dialog asking you a name for your output .glif file. If you save with Ctrl+Shift+U, MFEKglif will overwrite whatever the current filename is as a .glif, so if you've opened a.glif, it'll overwrite that; if you've opened a.glifjson, it'll write to a.glif. This flattens all layers, so you may instead want MFEKglif's most complex (and therefore potentially buggy! please open any issue you find) mode of saving: exporting—Ctrl+E. This will create a new directory for every layer in your glyph and save the layer into it, flattening layer groups.

I typically build and run MFEKglif like this:

RUST_LOG=debug RUST_BACKTRACE=1 cargo run -- examples/Q_.glif

We welcome all contributions! Please open an issue first so we can discuss before you make big changes so no effort is wasted.

It is possible to get even more debug output out of MFEKglif for figuring out where problems lie. To ask MFEKglif to dump the parsed .glif file on runtime, pass DEBUG_DUMP_GLYPH=Y. To see every single sdl2 event (warning: this will flood your stdout) pass DEBUG_EVENTS=Y.

Icons are themselves .glif files, see resources/fonts/MFEKglifIconFont.ufo/glyphs. Once you add a glyph to the UFO, you can rebuild the font (provided you have fontmake) with make iconfont.

Contributions which do not work on at least GNU/Linux and Windows will be rejected; we want to be able to build MFEKglif on as many platforms as possible. Both Skia and Dear ImGui are cross-platform; we use Vulkan and not OpenGL so we are future-proof even on OS X.

Contibutions will also be judged on how well they fit into the MFEK project as a whole. It's possible that your idea fits better into another module and not MFEKglif; we can help you figure out where it should go.

Copyright 2020–2021 Fredrick R. Brennan, Matthew Blanchard & MFEK Authors

Licensed under the Apache License, Version 2.0 (the "License"); you may not use
this software or any of the provided source code files except in compliance
with the License.  You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed
under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
CONDITIONS OF ANY KIND, either express or implied.  See the License for the
specific language governing permissions and limitations under the License.

By contributing you release your contribution under the terms of the license.