PixelCNC v1.62b Overview & Summer Sale!

PixelCNC v1.62b is live and its release is accompanied by a 60% off sale for the duration of the northern hemisphere's summer season. :)

Firstly, I'd like to point out that v1.62b removes some limitations on the free trial version of PixelCNC. The session time limit that was previously 60 minutes is now gone - as is the limit on the number of G-code moves that will be included for each operation in exported G-code. The saving of project files and exporting of canvas heightmap images/meshes remain reserved for owners who have activated PixelCNC.

The rest of this post details the more significant changes that are included with the v1.62b update. The rest of the changes can be viewed via the Help menu after installing the v1.62b update.

Parametric Supershape Stamping Tool

 It is now much easier to create a variety of radially and axially symmetrical shapes using the new Supershape Stamp tool that can be used while editing paths-layers. Shapes are specified through a number of parameters that can be adjusted. Several presets are available for quickly producing common shapes, and a few others.

These shapes can be directly used as toolpaths via the 2D milling operation types as well as the Medial-Axis Carving operation found under the Specialty Cuts op type category. They can also be used to create 3D shapes via the Shapes From Paths and Stroke Paths functions, as well as the Sweep Paths and Raster/Text Along Paths functions.

2D Repetition G-Code Export

 The G-code export dialog now includes provisions for repeating each operation's toolpath in a grid by a number of columns and rows with a specified spacing between each. This allows users to setup their CNC to cut multiples of a project.

Improved Canvas Rendering 

 There's been a long-standing issue with the way PixelCNC renders the canvas. To ensure optimal rendering speed on all graphics hardware PixelCNC employs a very efficient polygon-stack rendering strategy that is ultra-friendly to underpowered graphics hardware. This approach falls apart, however, when the canvas isn't being viewed from above. As such, additional polygon stacks along the horizontal viewing axes have been added to mitigate the issue. This is at the expense of a negligible amount of memory and compute time when updating the canvas geometry (which occurs only when modifying the canvas properties or Canvas Geometry setting under CNC/CAM Settings).

In the animation above the view is zoomed in to better illustrate the principle that is at play. From more common zoom levels the rendering artifacts are not apparent, whereas with earlier versions of PixelCNC you simply could not view the canvas from the sides at any camera zoom without it vanishing as the camera peered between polygons.

Users can reduce the Canvas Geometry setting via the CNC/CAM Settings dialog if they find that rendering is inconveniently slow or sluggish when the camera approaches horizontal viewing angles. This rendering technique employs more geometry for the horizontal viewing axes due to most projects having larger XY dimensions than Z for the canvas, which may incur a visible performance hit on less capable graphics hardware. Alternatively, users can enable the Fast View Update option found on the View Settings dialog. This option renders a much coarser canvas while the camera is moving, or when interacting with the canvas contents, and returns to a full geometric-resolution render once the view is no longer being interacted with.

This rendering feature has not yet been applied to the non-raymarched simulation rendering yet and remains affected by the horizontal viewing issue.

Narrow Trochoidal Cutpaths

 The algorithm for generating trochoidal cuts prevented them from being generated in tight narrow areas, due to a feedback effect that resulted from the stepover being reduced with the arc radius to accommodate narrower areas. This required a hard limit on the radius of the trochoid cut arcs themselves that prevented narrow areas from being cuttable at all.

v1.62b has rectified the situation by more closely adapting the stepover between cuts to a limit that's suited to the canvas resolution and the desired cut stepover. i.e. a higher canvas resolution and smaller stepover will allow for narrower areas to be cut while a lower resolution or larger stepover will prevent cuts from being entered.

In the example image above using a 1/4" end mill it's shown how v1.62b now will properly separate areas that are not reachable at a 50% stepover. Some leeway is still applied that allows the stepover to reduce to accommodate narrowness but beyond that margin it will simply consider the area not cuttable. At a 25% stepover the cut arc radii are able to go down to a smaller size and pass through the narrow areas that were not enterable at the 50% stepover.

Max Canvas Resolution to 1000ppi

 The canvas resolution was previously capped at 500 pixels-per-inch, which was fine for larger projects (which generally are fine with 200ppi or less) but for much smaller engraving type projects this was not enough. The limit has been increased to 1000ppi to allow for these small projects to retain the necessary resolution required for generating quality cutpaths.

In the example project pictured above, the text is 3/4" long and just about 1/8" tall (about 20mm x 3mm). The upper image is shown in PixelCNC v1.61b, with the max canvas resolution of 500ppi. A V-carve toolpath was generated using the medial-axis carving operation and saved. The project was opened in v1.62b and changed to 1000ppi and the medial-axis toolpath re-generated. It's subtle but the improvement in the cutpath quality is there.

It's important for users to keep in mind that the resolution of a project's canvas has a tremendous impact on the amount of processing time that's required to update the canvas during editing, and calculate toolpaths. A 2x doubling of canvas resolution equates to a 4x quadrupling of compute work. We strongly recommend that the lowest resolution required for a desired project fidelity be used for each project - otherwise a lot of unnecessary computation will be performed while working with a project. This can lead to many things taking much longer to calculate than is necessary.

Layer Move Up/Down Button Relocation

The buttons for moving the selected layer's position within the canvas layers list have been relocated to a fixed position in the user interface. This was intended to make it easier to re-arrange layers by simply clicking the buttons in series, for when layers need to be re-ordered by a decent amount.

Previously, PixelCNC had the buttons placed as small arrow-icon buttons which were visible on each layer, only when it was selected. This meant that moving a layer by multiple steps within the layer list required constantly chasing the small arrow buttons as the layer would shift up or down along the layers list.

The buttons may be moved closer to the layers list in a future update, perhaps immediately under the Layer Group buttons, eliminating the need to move the mouse back-and-forth between them and the layers list when there's a need to select and re-arrange multiple layers.

The Future

 It's time to make tutorial videos! There are also some improvements to the website that will be made over time.

Let us know what you think about this update and what you'd like to learn how to do in PixelCNC by posting a comment below, posting on the forum, or sending us an email at: support@deftware.org