dillonhuff/gpr

A simple C++ G-code parser

Synopsis

GPR is a small, MIT license, C++11 G-code parser. It is intended to provide the lowest level of parsing for G-code, breaking up raw G-code text into blocks consisting of comments and word-address style commands.

What is G-code?

G-code is the universal language of machine tools. It is used to control everything from mills and lathes to EDM machines and 3D printers.

Though the syntax and semantics of g-code are officially defined by ISO 6983 it is not really a single language. Different machine vendors implement different subsets of the standard and different non-standard extensions for their own equipment.

What everybody agrees on is that G-code programs consist of blocks, which are really just lines of text. Each block consists of:

1. An optional block delete character '/'
2. An optional line number
3. Any number of words, parameter settings and comments
4. An end of line marker (carriage return)

G-code emitted by modern CAM systems usually consists mostly of comments and words. For example the G-code program below has 4 blocks: 1 comment, and three movement commands.

(*** Toolpath 1 ***)
G0 X0.0 Y0.0 Z0.0
G1 X1.0 F23.0
G1 Z-1.0 F10.0

Since the interpretation of G-code commands varies from vendor to vendor this parser does not make any attempt to interpret G-code commands. It simply parses G-code and returns the parsed blocks.

G-code Dialects Supported

This parser has been tested on 5 different G-code samples which are in the gcode_samples folder

1. RepRap: A common G-code dialect used by 3D printers like the monoprice select mini, the sample was produced by Cura.
2. LinuxCNC: The sample in the github repo was produced for a 3 axis mill by an experimental CAM system from Stanford.
3. Vectric: Generated by VCarve Pro for a CAMASTER router
4. HAAS: Taken from a machinists forum post.
5. Mazak: Produced by Mazak's Mazatrol to G-code converter.

Build Instructions

cmake .
make -j
./all-tests

Feedback

If you use this parser in your own project I would really like to hear from you about it. Let me know what you liked and what could be better, and if you like this parser please give the repo a star!

gpr's Issues

parser.cpp segmentation error

Hi, @dillonhuff
Faced the problem of parsing this non-standard code. M76 X Or something like that, without the address at the end.

There is a segmentation error in the line 249.

string next_next = *(s.remaining() + 1);

Perhaps it's worth checking the presence of the address somehow?

if (s.remaining() + 1 != s.end()) {
    string next_next = *(s.remaining() + 1);

    if (!is_num_char(next_next[0])) {
        return parse_isolated_word(s);
    }

    return parse_word_address(s);
}
return parse_isolated_word(s);

Could not execute the sample tests

Hi, I tried to download the GCode parser and run the

cmake .
make -j
./all-tests

but it returned with a failure:
error.pdf

"Library not loaded: @rpath/libgpr.dylib" when running tests/example

cmake .
make

then

$ ./all-tests
dyld[97154]: Library not loaded: @rpath/libgpr.dylib
  Referenced from: /Users/bramp/gpr/all-tests
  Reason: tried: '/usr/local/lib/libgpr.dylib' (no such file), '/usr/lib/libgpr.dylib' (no such file)
Abort trap: 6

Same issue with ./parse-gcode.

I don't understand dynamic linkers enough, but this is on a Mac.

Support the parsing of decimal gcode / sub codes

Prusa has a set of sub codes codes documented here. For example:

M862.1 P0.4 ; nozzle diameter check
M862.3 P "MK3S" ; printer model check

This appear in gcode files I generate with Prusa Slicer. gpr will parse them, but it seems to drop the decimal part, ".1", ".2", etc.

Wondering if it does text/numbers to Gcode

Hello,

I have a small question. I'm looking for a program that can run in a commandline that will output gcode from an input from a string (numbers and text). I was wondering if this does that?

Comments?

Nice code, but please make it a habbit to add comments.

What is a chunk?
What is a block?

How can I see the data in the debugger? (QT Creator)

Thanks :)

run all tests failed

I successfully build the code but when I run the all test, it gives me the error:

all-tests is a Catch v1.3.1 host application.
Run with -? for options

-------------------------------------------------------------------------------
Full sample parsing
  Parse HAAS sample
-------------------------------------------------------------------------------
/home/flexiv/Downloads/gpr/test/parser_tests.cpp:170
...............................................................................

/home/flexiv/Downloads/gpr/test/parser_tests.cpp:203: FAILED:
due to a fatal error condition:
  SIGSEGV - Segmentation violation signal

===============================================================================
test cases: 19 | 18 passed | 1 failed
assertions: 28 | 27 passed | 1 failed



It seems the parser did not succeed when handling the file HAAS_sample.NCF.