Abstract: In this work, we present an interactive interface for sketching synthesized textures. Reaction-Diffusion (RD) is used as the basis for texture synthesis. RD allows an unlimited amount of non-repeating texture and offers great flexibility for mapping textures to arbitrary surfaces. However, it can be difficult to find starting values of parameters that will produce interesting patterns. We use machine learning to resolve the difficulty of determining appropriate initial values of the RD system. The system described here allows a user to sketch a pattern of spots or stripes with arbitrary orientations, and then automatically generates a pattern with the same attributes as the sketch. It also allows the user to interactively create more complex textures by adding another layer of pattern, as well as manipulate the color of the resulting texture. We also show that this procedure can be applied to realistic 3D surfaces.