In the original plan, LeWitt doesn't specify the number of arcs to be drawn, but leaves this decision to the draftsperson. I have modified this drawing so that moving the mouse left and right across the surface of the image changes the number of arcs drawn. When the mouse is at the far right, there is only one arc drawn from either side and when the mouse is at the far left, there are over five hundred. As the mouse moves left, the arcs visually collide, creating a moiré pattern. This is a technically trivial change introduced with one line of code, but I feel it is a radical re-invention of LeWitt's concept and reveals the potential for creating responsive drawings in a software environment.
My favorite mouse region is the upper left corner. The moiré patterns that emerge are quite remarkable.
The moiré pattern is my favorite part of this exploration. I wonder how the moiré pattern would change if the arcs drawn did not have to abide by the limitations in resolution attributed to pixel-based monitors. It is quite striking to see the drastic change in composition when comparing far-right mouse position results with far-left mouse position results. Two simple very predictable arcs compared to a veritable chaos of symmetrical noise.
Wall Drawing #106
Arcs from the midpoints of two sides of the wall.
Modification: The horizontal position of the mouse is used to dynamically change the density of the arcs.
Implemented as software by Casey Reas