Mecode

From RepRapWiki
Jump to: navigation, search

Mecode is an open source library for generating GCode. It is written in python and licensed under the MIT license.

You can find the source code on github: https://github.com/jminardi/mecode

Mecode is designed to simplify GCode generation. It is not a slicer, thus it can not convert CAD models to 3D printer ready code. It simply provides a convenient, human-readable layer just above GCode. If you often find yourself manually writing your own GCode, then mecode is for you. Mecode can generate basic GCode commands like line and arc, as well as composed commands like rectangles and meanders.

Contents

Basic Use

To use, simply instantiate the `G` object and use its methods to trace your desired tool path.

from mecode import G
g = G()
g.move(10, 10)  # move 10mm in x and 10mm in y
g.arc(x=10, y=5, radius=20, direction='CCW')  # counterclockwise arc with a radius of 5
g.meander(5, 10, spacing=1)  # trace a rectangle meander with 1mm spacing between passes
g.abs_move(x=1, y=1)  # move the tool head to position (1, 1)
g.home()  # move the tool head to the origin (0, 0)

By default mecode simply prints the generated GCode to stdout. If instead you want to generate a file, you can pass a filename and turn off the printing when instantiating the `G` object.

g = G(outfile='path/to/file.gcode', print_lines=False)
  • NOTE: `g.teardown()` must be called after all commands are executed if you are writing to a file. This can be accomplished automatically by using G as a context manager like so:
with G(outfile='file.gcode') as g:
    g.move(10)

When the with block is exited, g.teardown() will be automatically called.

The resulting toolpath can be visualized in 3D using the `matplotlib` or `mayavi` package with the `view()` method:

g = G()
g.meander(10, 10, 1)
g.view()

The graphics backend can be specified when calling the `view()` method, e.g. `g.view('matplotlib')`. `'mayavi'` is the default graphics backend.

All GCode Methods

All methods have detailed docstrings and examples.

  • set_home()
  • reset_home()
  • feed()
  • dwell()
  • home()
  • move()
  • abs_move()
  • arc()
  • abs_arc()
  • rect()
  • meander()
  • clip()
  • triangular_wave()

Matrix Transforms

A wrapper class, `GMatrix` will run all move and arc commands through a 2D transformation matrix before forwarding them to `G`.

To use, simply instantiate a `GMatrix` object instead of a `G` object:

g = GMatrix()
g.push_matrix()      # save the current transformation matrix on the stack.
g.rotate(math.pi/2)  # rotate our transformation matrix by 90 degrees.
g.move(0, 1)         # same as moves (1,0) before the rotate.
g.pop_matrix()       # revert to the prior transformation matrix.

The transformation matrix is 2D instead of 3D to simplify arc support.

Renaming Axes

When working with a machine that has more than one Z-Axis, it is useful to use the `rename_axis()` function. Using this function your code can always refer to the vertical axis as 'Z', but you can dynamically rename it.

Credits

Mecode is currently maintained by Jack Minardi at Voxel8.