Optical Color Mix Abstract Vector Filter
Optical Color Mix samples the original source image before ordinary one-swatch color quantization can discard intermediate colors. For each mixing cell, it compares the target source color with every available direct swatch and with the dot ratios representable by every pair of available swatches. When a direct palette match is adequate, all ordinary processed swatch geometry in that cell remains continuous vector geometry. Only a cell better represented by a two-swatch calculation becomes non-overlapping marks on the component swatches' LightBurn layers.
What the filter is doing
This is a hybrid of ordinary Rasterizer vectors and spatial color mixing. Areas already represented adequately by available palette swatches remain continuous filled vector regions. Viewed closely, only the unavailable-color areas reveal individual component-color marks; viewed from farther away, the eye may average those marks into another perceived color.
Direct Color Preference controls how much improvement a calculated mixture must provide before the filter replaces a cell's normal vectors with the extra dot-layer complexity.
Matching models
Perceptual Lab is the recommended default. It mixes the declared swatch colors in linear-light RGB, converts the predicted mixture to Lab, and selects the candidate with the smallest normalized perceptual difference from the source target. Linear RGB compares optical intensities directly. Creative HSV compares hue, saturation, and value and may produce more stylized choices.
The Mixing Model selector is categorical rather than numeric and is therefore described here instead of in the numeric control table below.
Mixing cells and dots
Dot Pitch sets the physical center spacing. Mixing Cell Dots sets how many dot rows and columns form one ratio cell: a 4-by-4 cell provides 16 positions and therefore represents pair ratios in sixteenth-sized steps. Dot Size Ratio changes mark coverage without allowing neighboring marks to overlap.
Smaller pitch can improve blending but creates more vector objects and may demand marks near or below the effective laser spot size. Larger mixing cells provide more precise ratios but make color transitions coarser. Begin with a small test at the intended viewing distance.
Uncalibrated correction controls
Hue Shift, Saturation Gain, and Brightness Gamma alter the predicted appearance of every available swatch before mixture selection. Dot Influence changes how strongly the minority swatch is predicted to affect a mixture compared with its geometric coverage. Neutral Bias discourages or favors Black and gray participation. These are global approximations, not substitutes for measured per-swatch calibration.
Pattern Seed changes the repeatable arrangement of the same component ratios. Square Dots replaces circular marks with squares while preserving exclusive layer ownership.
Physical limitations
Declared RGB values do not fully predict oxide color, diffraction color, spectral reflectance, viewing-angle changes, illumination, focus, heat accumulation, scan-length behavior, or how a setting developed for a large fill behaves on a small mark. Optical Color Mix can expand useful perceived transitions between available swatches, but it cannot guarantee a requested color or synthesize colors outside the practical gamut of the engraved component marks.
Open the generated project in LightBurn, verify that every component layer has the intended tested setting, engrave a small sample, and adjust the correction controls from the physical result before producing large artwork.
Control reference
Ranges and defaults below come directly from the current filter implementation.
Dot pitch
Sets the physical center-to-center spacing of the optical mixing marks. Smaller spacing improves viewing-distance blending but increases mark count, file size, and sensitivity to laser spot size.
Analogy: Choosing how fine the colored dots are on a printed image.
Mixing cell dots
Sets the width and height, in dots, of each ratio cell. Larger values provide finer two-color ratio steps but represent source-color changes over a larger physical area.
Analogy: Using more tiles in each mosaic block so its color ratio can be measured more precisely.
Dot size ratio
Sets each mark's diameter or width as a fraction of Dot Pitch. Lower values leave more unmarked metal between dots; higher values increase coverage without allowing neighboring marks to overlap.
Analogy: Changing the diameter of printed dots without moving their centers.
Direct color preference
Penalizes two-swatch mixtures so a nearby direct swatch is retained unless mixing improves the predicted match enough. Higher values create fewer mixtures and generally simpler projects.
Analogy: Choosing a paint straight from the tube unless mixing clearly improves the match.
Hue shift
Rotates the predicted physical swatch colors before mixture selection to compensate approximately for a consistent warm, cool, or hue-direction error.
Analogy: Turning the reference color wheel to compensate for a consistent tint.
Saturation gain
Scales the predicted saturation of every available swatch before calculating mixtures. Use values below 1 when engraved colors appear duller than their declared swatches and values above 1 when they appear stronger.
Analogy: Adjusting a global color-intensity control before mixing paint.
Brightness gamma
Curves the predicted brightness of available swatches before mixture selection. Values above 1 predict darker physical results; values below 1 predict brighter results.
Analogy: Correcting a display that consistently renders midtones too dark or too light.
Dot influence
Changes how strongly the minority swatch is predicted to affect a mixture compared with its geometric dot count. Values above 1 make minority dots count more; values below 1 make them count less.
Analogy: Accounting for a strong pigment that changes a mixture even when only a little is present.
Neutral bias
Discourages or favors Black, gray, and low-saturation swatches during mixture selection. Positive values reduce their use; negative values invite them into more mixtures.
Analogy: Deciding how readily gray paint may be added to every color mixture.
Pattern seed
Changes the repeatable distribution order of component-color dots without changing the selected ratios. The same value recreates the same layout.
Analogy: Rearranging the same quantities of colored tiles while preserving their totals.
Square dots
Changes the marks from circles to grid-aligned squares.
Analogy: Switching a printing screen from round ink dots to square pixels.
Keep available colors as vectors
Keeps ordinary continuous vector geometry wherever a palette swatch adequately represents the source color. Turn it off to render direct matches and calculated mixtures alike with the dot matrix.
Analogy: Printing colors already available as solid ink while screening only colors that need to be mixed.