Through November 8, the paintings of Miami-based artist Xavier Cortada will be on display at the Galeria Sol y Luna, 510 E. Houston, San Antonio (210-354-3433).   Cortada, a native of New York and a Cuban American, paints from his own urban and cultural experience, in bold colors and strong textures, as seen in this painting, Torso 3.  Admission to the gallery is free.