Contents
Islamic Pattern generates a repeating star rosette with alternating filled regions and crisp geometric outlines. Based on the mathematical modeling of symmetric Islamic design (Kaplan et al., 2019), it constructs complex {k, N} star polygons by rotating a point around a circle using alternating angle steps. The result creates the characteristic spiked stars, concave valleys, and interlocking strapwork found in traditional tilework, with full control over the star shape, line thickness, and region coloring.
Usage & Behavior
This node is unique because it is not just a texture lookup; it performs real-time geometric construction. The pattern is defined by two integers: N (the number of vertices) and K (the step interval). By changing these values, you can morph the pattern from simple stars to intricate, self-intersecting webs. The Line Width parameter allows you to create the "strapwork" look (lines separating colored tiles) typical of Alhambra mosaics. Not all k, N parameters will give back a regular pattern, so experiment a bit with those.
Key Features
- Geometric Construction: Uses the {k, N} star polygon math for authentic rosette shapes.
- Strapwork Generation: Automatically creates outline paths between filled regions.
- Region Coloring: Alternates colors based on even/odd crossing rules.
Parameters
- Low K: Open, convex shapes.
- High K: Sharp, spiky, self-intersecting stars.
Colors
Quick Recipes
Traditional configurations.
Classic 8-Point Rosette
- N 8
- K 2
- Line Width 0.05
Complex 12-Fold
- N 12
- K 4
- Radius 1.2
Simple Lattice
- N 6
- K 1
- Line Width 0.1
- Colors Same
raySegmentIntersection) to determine if a pixel is inside or outside the star polygon. By counting the number of "crossings" from the center to the pixel, it determines the fill color (even vs odd winding rule). However take care that ray-casting breaks down when applied to self-intersecting polys (ie. here stars) in a tiled domain where boundaries wrap, so coloring in some circumstances won't work correctly.