If “Xstraction” is a fair indicator, abstract painting is in a desultory state these days. The works here, by 36 artists, represent a wide range of familiar approaches.

The greatest number of participants focus on materials and processes. Andrew Sutherland made his large all-white Robert Ryman-like piece by applying unfolded and painted plastic trash bags to a stretched canvas, creating a pleasing surface of grided folds and creases. Ayan Farah stains see-through pieces of cotton silk with pale dyes and stretches them around wooden frames. Oscar Murillo adds small smudges and smears of paint and pieces of tape to dirtied raw canvases. While ostensibly unorthodox, works like these and many others in the show, including those made by digital means, invite a traditional connoisseur’s appreciation of formal aesthetics.

A smaller number of artists play with optical perception. Anoka Faruquee’s compact paintings made of fine, arcing parallel lines in multiple layers produce moiré effects. A composition of soft-focus horizontal and vertical bands by Adam Henry blurs in the central area as if obscured by a foggy cloudlet. These pieces alert viewers to the ways perception alters reality.

A metaphorically intriguing piece by Thomas Øvlisen is in the form of a heavily painted open frame the size and shape of a narrow door. The frame’s inner edge is rough, as if the door had been violently broken through. While most of the show’s artists remain preoccupied by surface aesthetics, as Mr. Øvlisen, this particular object suggests that for imaginative painters, abstraction may still be a portal to uncharted possibilities.