Imaging systems and techniques are described. An imaging system determines, based on image data of a scene received from an image sensor, a movement path of an indicator object relative to a target object. The target object is represented in the image data from a first perspective. The imaging system identifies, based on the movement path of the indicator object and the first perspective, an outline of at least a portion of the target object. The imaging system generates a three-dimensional mesh based on the outline of at least the portion of the target object. The imaging system can generate the mesh additively or subtractively, by adding a volume based on the outline to a previous mesh or by subtracting the volume from a previous mesh, respectively. The imaging system can generate a texture for the mesh that is based on the target object in the image data.