Krasnow Color Grating Abstract Vector Filter

Preserve Black

With Preserve Black enabled, source-derived Black remains ordinary closed Black geometry using the matched Black Cut Setting, while other regions become gratings. With Preserve Black disabled, Black is treated like the other colors: its regions become grating lines and its LightBurn layer receives a clone of the Fauxlographic carrier setting.

The output does not place a full Black backing shape underneath the grating layers. Prepared regions have exclusive ownership so multiple laser settings do not engrave the same footprint.

Cell shapes and packing

Gap-free layouts include Square, Hexagon, Triangle, Diamond / Rhombus, and Puzzle Piece. The staggered Skull, Heart, Space Invader, Ghost, Bat, Alien Head, Paw Print, and Fish Scale layouts intentionally expose substrate between silhouettes. Patch Size determines the physical cell scale; it is independent of the processing pixel size.

When a cell covers multiple processed pixels, the prepared region and source samples within that cell determine its clipped ownership, angle, and carrier selection. Smaller cells retain more local variation but generate more geometry.

Visible line spacing

Line Spacing controls the visible distance between the parallel paths inside a cell. Hue Line Spacing Minimum and Maximum optionally vary that visible density by approximate wavelength order: violet and blue lie near the minimum and red near the maximum; purple and magenta follow a continuous violet-to-red proxy. Equal minimum and maximum values preserve uniform spacing, and low-saturation colors use Line Spacing.

These visible hatch distances are separate from the microscopic along-path pulse pitch created by laser speed and frequency.

Angle and color routing

Source luminance maps between Angle Minimum and Angle Maximum. For sufficiently saturated source colors, Hue Rotation and Ben Krasnow's inverse hue mapping contribute to the carrier-layer selection. The gradient endpoints and Gradient Curve add a position-dependent offset. Colors at or below Saturation Cutoff omit the hue contribution and use only that gradient.

In the dedicated Krasnow Color Grating abstract filter, Gradient Top and Gradient Bottom retain the established top-to-bottom artwork-wide behavior. In the Krasnow Grating Geometry Style, those endpoints are labeled Fauxlogram Gradient Start and Fauxlogram Gradient End, and the additional Scope and Direction controls determine where and how the progression is evaluated.

Fauxlogram Gradient controls in Geometry Style

Fauxlogram Gradient Scope offers Entire Artwork and Each Shape. Entire Artwork evaluates every grating cell against the bounds of the complete prepared artwork. Each Shape restarts the progression inside every disconnected prepared vector component, so separate objects can each receive a complete gradient.

Fauxlogram Gradient Direction offers Top to Bottom, Bottom to Top, Left to Right, Right to Left, Center to Edge, and Edge to Center. The radial choices use an elliptical normalized distance from the relevant artwork or shape center, so whole-artwork radial layouts are supported as well as shape-local radial layouts.

The Start and End values define the two ends of the carrier-selection offset, while Gradient Curve redistributes the transition between them. These controls change carrier-layer selection; they do not rotate the parallel grating paths. Angle Minimum and Angle Maximum still control line orientation. Touching regions that have already merged into one prepared component are treated as one shape, and very small shapes may contain too few cells to display a smooth progression.

Fauxlographic carrier setting

The selected material must contain a Cut Setting Entry identified as Fauxlographic. Rasterizer uses the Fauxlographic setting as the authoritative template and clones its power, frequency, pulse width, passes, and other applicable settings onto the grating carrier layers. Additional sublayers, if present, are ignored because the generated diffraction gratings rely on one precise Cut/Line operation. The clone retains each destination layer's LightBurn identity; calculated speed is adjusted for its target pulse pitch.

If a source field such as q-pulse width is genuinely absent, Rasterizer leaves it absent rather than inventing a device default. LightBurn may display a device-dependent value after opening the project.

Pulse pitch and Speed Spread

Along-path pulse pitch is speed divided by frequency. Rasterizer treats the Fauxlographic anchor speed and frequency as a machine-specific 1.00 µm reference and distributes target pitches across the available grating carriers. Speed Spread controls their divergence from that anchor: 0 keeps every carrier at the anchor speed, 1 uses the normal range, and 2 doubles the deviation.

The organizational RGB color of a LightBurn layer does not itself predict the physical diffraction color. Material, focus, optics, pulse behavior, illumination, and viewing angle all affect the observed result.

Abstract filter versus Geometry Style

Use the dedicated Krasnow Color Grating abstract filter for the established all-in-one workflow. Its correction remains an artwork-wide top-to-bottom gradient. Use Krasnow Grating as the Geometry Style when another compatible Image Style should transform the regions first or when shape-local, horizontal, or radial fauxlogram gradients are needed. No geometric effect plus Krasnow Grating with Entire Artwork and Top to Bottom provides the closest comparison to the dedicated filter; another Image Style intentionally changes the geometry entering the grating stage.

Physical validation

The calculations cannot verify that a particular machine and material produce the assumed diffraction response. Confirm every generated layer and setting in LightBurn, check that calculated speeds and frequencies remain within machine limits, and engrave a small test under the intended focus, lighting, and viewing conditions.

The approach is based on Ben Krasnow's MOPA Laser Diffraction Gratings reference project, adapted to the selected Rasterizer palette and Fauxlographic setting.

Control reference

Ranges and defaults below come directly from the current filter implementation.

Related documentation

• Geometry Styles and Per-Swatch Geometry Routing
• Abstract Raster-to-Vector Filters
• Color Separation: Rasterizer Swatches, Vector Geometry, and LightBurn Layers
• Laser Diffraction Gratings and Structural Color
• Generate a Fauxlographic Diffraction Calibration Grid