fixed skew transformations

[MaxGraey]

Motivation:
fix#11884 issue

@sahrens@vjeux

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[vjeux]

@jordwalke you wrote that code, could you review it please? Thanks!

[MaxGraey]

Hi, @jordwalke. I will try in short to explain what was wrong.
Let's look to transformation's matrix for skewY for example.

Was

cos(a)	sin(a)	0	0
0	1	0	0
0	0	1	0
tx	ty	tz	1

Yes, this visually produce skewing transform but it slightly incorrect. This way affects horizontal scale as well. See this

Now with PR

1	tan(a)	0	0
0	1	0	0
0	0	1	0
tx	ty	tz	1

According to www.w3.org/css-transforms

Only one differance React Native use row major matrix style, so we change m[0][1] instead m[1][0].

[vjeux]

Thanks for the thorough explanation, that sounds good to me. I just clicked the land button, so unless something goes wrong, it's going to ship in the next tens of minutes! Thanks!

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[vjeux]

I think something went wrong with your rebase

[MaxGraey]

@vjeux My last fork was 5 days ago, so I try to remote update to actual base, but anyway I still have unresolved 2 conflicts. What would you recommend?

[vjeux]

Since your diff is so small ( 7aefe36 ), I would recommend removing this whole branch, applying it back manually and sending a force update. The git commands should look something like:

gitcheckoutorigin/master;gitbranch-Dmaster;gitcheckout-bmaster;// apply the changesgitcommit// copy paste the description from githubgitpush-fMaxGraey

In the future, I recommend that you create a branch with

gitcheckout-bfix_skew

this way you don't need to work on master and you can have multiple of them going on.

[vjeux]

Looks like there are still a lot of spurious changes :(

[MaxGraey]

@vjeux I choose second approach

New PR from fix-skew