LayoutProperties is an optional part of Morph using some type of defined layout (mostly used by the LayoutPolicy subclasses), this is though not the only way to do layout for a Morph and its submorphs; so not every morph needs it nor should have it. Best regards, Henrik From: Pharo-dev [mailto:pharo-dev-bounces@lists.pharo.org] On Behalf Of Aliaksei Syrel Sent: Sunday, January 31, 2016 1:17 PM To: Pharo Development List <pharo-dev@lists.pharo.org> Subject: Re: [Pharo-dev] 17502. Morph layoutProperties must not be nil by default layoutProperties := NullLayoutProperties uniqueInstance to share only one object On Sun, Jan 31, 2016 at 1:06 PM, Esteban Lorenzano <estebanlm@gmail.com<mailto:estebanlm@gmail.com>> wrote: On 31 Jan 2016, at 12:43, Denis Kudriashov <dionisiydk@gmail.com<mailto:dionisiydk@gmail.com>> wrote: Hi. Wait, I do not like this... remember *anything* can be a Morph, not just a widget (points, "atoms bouncing", etc.). Could you explain it? Because you can't add point to morph for example. A morph can be a point. If you define: Morph new color: Color yellow; extent: 1@1; position: 10@10; openInWorld. you will have a âpointâ in the world. Now imagine 10k of those (to run simulations or whatever). Thatâs what I mean :) 2016-01-31 12:21 GMT+01:00 Esteban Lorenzano <estebanlm@gmail.com<mailto:estebanlm@gmail.com>>: no, I donât :) I commented there. On 30 Jan 2016, at 21:22, Aliaksei Syrel <alex.syrel@gmail.com<mailto:alex.syrel@gmail.com>> wrote: Hello Do you agree? https://pharo.fogbugz.com/f/cases/17502/Morph-layoutProperties-must-not-be-n... Cheers, Alex