SH view space

[CedricGuillemet]

Fix viewdirection to make SH computation happen in GS local coordinates.

Tested with https://playground.babylonjs.com/#CID4NN#278

set ofs to true to add a rotation and translation offset. Rendering should be the same with of without this offset.

NOTE : I'll wait for partners feedback before merging it.

[bjsplat]

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[bjsplat]

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[bjsplat]

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[bjsplat]

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[sebavan]

Converted as draft while you are awaiting partner feedback but looks all good to me