Line Tracing

[Stoli123]

In an older version, when I chose to Create G-Code from Image, I could select a mode that started at the top and moved down line by line. I assume that is "Line Tracing". When I select that mode, it seems to do the same thing that Vectorization does. Is that by design?

[svenhb]

The working prinziples are different (Form GCode from Image https://grbl-plotter.de/index.php?id=form-image&setlang=en):
In 'Line tracing' one by the other image pixel will be processed - line by line, in spiral pattern or other pattern to generate Z or S value. Better use 'B/W grayscale mode'.
In 'Vectorization' pixel with same color will be collected in shaped which can be filled. REcommend with 'Color mode'.

Via setup, you can define 'Auromatic vectorization' (https://grbl-plotter.de/index.php?id=form-setup-1#format-related):
Loaded image will be vectorized directly, without opening any form for setup. Using different algorithm for vectorization.
Only doing black/white. Was made for this kind of art: https://youtu.be/3JnVT8EVs3w

[Stoli123]

OK. So it sounds like you might have changed the algorithm. Before, when I went Line by line, and chose Top Down, the Y value in the gcode would start at the highest value and work its way down to the lowest value one step at a time. It would sort of act like a printer (top to bottom). Now, the line by line starts at the top, but when it finds an area, it will follow the outline of that area (decrease Y, all the way to zero if applicable) and then at the end of the file, it goes back and fills in the outlined areas.

[svenhb]

In B/W mode it still works top-down:

[Stoli123]

OK. Thanks. I noticed that but it varied the Z height based on the gray scale value and I'm needing an On/Off value for Z. Basically either ON (Z-3.0) or OFF (Z2.00). I'll explore those settings when I get a chance. Thanks for your time. I'm always amazed at your quick response!!!

[svenhb]

For on/off, just convert the image to black and white before creating the code (b/w or dithering):

[Stoli123]

Thanks again. Another question regarding Sorting. I'm importing an SVG file with multiple objects (paths) that are filled, so I am applying a hatch fill. Is there a combination of settings that would plot each object (outline and fill) in it's entirety from upper left to lower right? I can set the initial start point (Xmin, Ymax), but some objects are skipped, or only partially drawn and are finished after everything else is drawn.

[svenhb]

The sorting algorithm is somewhat simple: From the initial starting point, it searches for the nearest starting point of a figure, at the end of this figure it searches for the nearest starting point of the next figure.

You could use grouping, to keep objects together (if they use same color, pen-width or layer) https://grbl-plotter.de/index.php?id=form-setup-1#grouping