Hardware Heritage
The Moire pattern is a classic example of visual interference. In retro computing, it wasn't just a mathematical curiosity, but a way to generate complex, shifting textures from simple, overlapping shapes.
Amiga XOR
Amiga coders leveraged the Blitter's hardware XOR mode. By blitting a static circular pattern over itself with a sub-pixel offset, the chipset generated complex interference fringes instantly with zero CPU cost.
PC Math
On PC, this served as a CPU benchmark. Calculating the distance for every pixel to draw the overlapping rings tested the machine's ability to handle high-frequency integer loops and fixed-point math.
Discrete Grids
Moire patterns are the visual byproduct of overlapping discrete grids—a hallmark of the "aliased" era of graphics where every pixel was a distinct, hard-edged unit.
Moire Pattern
The visual hum of geometric collision.
Legacy ASM (XOR)
; Amiga Blitter XOR mode move.w #$0B00,BLTCON0 move.l #Pattern,BLTAPTH move.l #Screen,BLTCPTH move.l #Screen,BLTDPTH move.w #$0000,BLTAMOD
Modern GLSL
float d1 = length(uv - p1) * 30.0; float d2 = length(uv - p2) * 30.0; float c1 = mod(floor(d1), 2.0); float c2 = mod(floor(d2), 2.0); float final = (c1 != c2) ? 1.0 : 0.0;