Few questions - Githubissues

martindevans / Cassowary.net

An incremental constraint solver for .NET

http://jozilla.net/Software/CassowaryNet

GNU Lesser General Public License v2.1

3 stars 5 forks source link

Few questions #7

Closed krypt-lynx closed 4 years ago

krypt-lynx commented 4 years ago

how to do constraint priority in this implementation? I see ClStrength and ClSymbolicWeight, first requires second and ClSymbolicWeight requires 3 numbers to init. What are those numbers?
I'm trying to wrap my head around and don't see solution yet: how to do nested constraints? For example: I have a view inside a view, and I need size of external view is constrained by one set of rules and internal one depends on size of external

Basically, I'm trying to understood it in terms of Apple's AutoLayout

martindevans commented 4 years ago

It's a long time since I've used this library, so I'm afraid I can't really remember these kinds of details, sorry :(

The original library which I forked was a port of this project. In particular this paper describes the details of the algorithm.

krypt-lynx commented 4 years ago

Thanks. Is it that thesis mentioned in original repository?

martindevans commented 4 years ago

Yep, it's link #2 in the readme.

krypt-lynx commented 4 years ago

Hi! I did quite a few changes in my repo (https://github.com/krypt-lynx/Cassowary.net)

Operator overrides based constraint builder (looks to be more stable, at least I can make calls in parameters)
ToString() readability
Some extra methods in ClSimplexSolver

Not creating merge requests because changes are making my fork incompatible with yours.

Also, looks like the original author cheated in his thesis... In this implementation Strengths are not sorted by order, like he states in it. So, Medium with weight = 1001 overpowers Strong with weight = 1 :( Also, ClStrengths and Epsilon values appears to be finetuned. (changing them breaks unit tests)