Hi I'm cleaning Sensor use so that we end up with a better layered system. Now I see this method and I wonder (replacing Sensor by hand does not work. But I do not understand why this methods has to explicitly invoke runStepMethods… to me it looks like a broken behavior due probably to the lack of a functionality or ticking behavior. What do you think? fromHand: hand "Let the user draw a polygon, clicking at each vertex, and ending by clicking within 5 of the first point..." "self fromHand: ActiveHand" | p1 poly oldVerts pN opposite | Cursor crossHair showWhile: [[Sensor anyButtonPressed] whileFalse: [self currentWorld displayWorldSafely; runStepMethods]. p1 := Sensor cursorPoint]. opposite := (Display colorAt: p1) negated. opposite = Color transparent ifTrue: [opposite := Color red]. (poly := LineMorph from: p1 to: p1 color: opposite width: 2) openInWorld. oldVerts := {p1}. self currentWorld displayWorldSafely; runStepMethods. [true] whileTrue: [[Sensor anyButtonPressed] whileTrue: [pN := Sensor cursorPoint. poly setVertices: (oldVerts copyWith: pN). self currentWorld displayWorldSafely; runStepMethods]. (oldVerts size > 1 and: [(pN dist: p1) < 5]) ifTrue: [hand position: Sensor cursorPoint. "Done -- update hand pos" ^ (poly setVertices: (poly vertices copyWith: p1)) delete]. oldVerts := poly vertices. [Sensor anyButtonPressed] whileFalse: [pN := Sensor cursorPoint. poly setVertices: (oldVerts copyWith: pN). self currentWorld displayWorldSafely; runStepMethods]].