Vagrearg - gcmc - G-Code Meta Compiler

gcmc - G-Code Meta Compiler

Introduction
Getting and building gcmc
Running gcmc
Changes
Bugs reports and feature requests
Gcmc documentation
Gcmc examples and screenshots

Introduction

Gcmc is a front-end language for generating G-code, SVG and DXF for CNC mills, lathes, laser cutters and other numerical controlled machines employing G-code, SVG or DXF. The language is a context-free grammar created to overcome the archaic format of G-code programming and aims to be more readable and understandable. Gcmc makes extensive use of vector mathematics to support the 3D nature of CNC machining.

An introduction document is available. The introduction goes through basic syntax and program outline and describes an example to create involute gears in under 200 lines of code (under 100 lines when excluding source code comments).

Getting and building gcmc

You can get the source from the link below. The windows executable is a 32/64bit MinGW cross-compiled command-line version.

Source tarball:	gcmc-1.9.2.tar.gz
Windows exe (32 bit):	gcmc32-1.9.2.zip
Windows exe (64 bit):	gcmc64-1.9.2.zip
Git repo:	https://gitlab.com/gcmc/gcmc

Please note: the git repository has been moved from gitorious.org to gitlab.com. You should rebase your local repository if you have cloned it.

Older sources are available and a SHA1 sum and/or SHA256 sum may be used to verify the archives.

Building from source is straight forward and should function on Linux, *BSD, MinGW/MSYS and Cygwin:

$ tar xzf gcmc-1.9.2.tar.gz
$ cd gcmc-1.9.2
$ ./configure
$ make

After 'make' you should have an executable in the 'src' directory named 'gcmc'. For a MinGW cross-compile you should use 'mingw32-configure' or 'mingw64-configure' or whatever your cross-target is and it should result in 'gcmc.exe' after running one of 'mingw{32,64}-make'.

Building on any system with a different set of autotools may require you to re-configure the setup. You should be able to run 'autoreconf -f' to update to your system. Be sure to do so for both gcmc and gcmcfont. See the first part of doc/debian.build on how to re-configure. This should work across distributions.

Running gcmc

Running gcmc, assuming you are in the src directory, is as simple as:

$ ./gcmc -o output.ngc input.gcmc

This will convert the input file "input.gcmc" into a G-code file "output.ngc". The output is written to stdout if no -o option is given. Stdin is used if no input file is given.

You may compile and inspect the examples by running (from the top or the example directory):

$ make examples

This will give you G-code, SVG and DXF versions of the examples, which can be inspected with the appropriate programs.

The gcmc man-page gives you a complete summary of all option.

Changes

gcmc-1.9.2 - 2024-05-21

Fix: Do not forget gcmcfont automake update

gcmc-1.9.1 - unreleased

Feature: Add lathmode() gcode function
Fix: Remove duplicate file in Makefile.am to allow proper install
Fix: Automake update

gcmc-1.9.0 - 2022-06-07

Feature: Add a debugger to debug gcmc scripts
Feature: Add SVG options -svg-no-pedantic and --dxf-no-pedantic to suppress warning about functions that cannot be mapped to the output format
Feature: Add SVG control of line width, color and opacity as special svg functions
Change: Make angular units consistent across the application by defaulting to radians; use the --degrees option for old behaviour
Fix: XZ-arc where radius sign was reversed
Fix: XZ-arc examples were wrong too
Fix: Properly highlight sign() function in syntax file
Fix: Do not emit unit-mismatch on comparison with literal constant zero
Fix: Cross-builds can now be both 32 and 64 bits and DLLs are properly collected

gcmc-1.8.3 - 2019-07-07

Fix: arc_* functions could generate a NaN in the SVG output
Fix: NaN and Inf now include sign due to changes newer printf behavior

gcmc-1.8.2 - 2017-02-19

Fix: spindle() function must first set speed with S before enabling spindle with M3/M4

gcmc-1.8.1 - 2017-02-11

Fix: Use-after-free bug in filename referencing when handling includes
Fix: Split the Bezier min-length and co-linear calculations to become slightly more accurate

gcmc-1.8.0 - 2016-07-25

Feature: Convert all internal string handling to Unicode (wchar_t)
Feature: to_float() and to_int() now can convert strings to values including units
Feature: Functions insert(), delete(), head(), tail() and reverse() can now operate on strings
Feature: Allow strings to be indexed as rvalues, returning the indexed character as string
Feature: Add to_val() and to_chr() functions to allow character manipulations
Feature: Add relocate() function to support adhoc relative offsets
Feature: Add TODO (wish)list
Fix: Several interpreter memory leaks plugged using valgrind
Fix: Allow delete() to delete all entries
Fix: Use correct source argument in insert() to insert into target
Fix: Fix relative arcs, specifically SVG, to use the correct movement
Fix: Fix arcs and circles, use global position whith undef end coord.

For older changes see Changes page for details.

Bugs reports and feature requests

Please report any bugs you may encounter to gcmc _at_ vagrearg.org. Please include an example that triggers the bug.

If you want more/extra/different features included, then write me an email with the request and a description what you want to add and want to achieve with the change or addition.

Gcmc documentation

gcmc man-page	All command-line options and switches.
gcmc introduction page	Starting with a simple step-by-step introduction to the basic concepts and ending with the creation of an example to create involute gears.
gcmc syntax page	Detailed description of language syntax and its semantics.
gcmc function reference page	All built-in functions described with all parameters, types and operational modes.
gcmc library page	Library functions are more complex operations like tool compensation and canned drill sequences.