Questions about unwraping UV and Normal map

Klo Works

Hi,
I want to know which one is better .

P1 :



for baking normal map ,the select part is it ok to share ? or better leave it ? is it gonna cause some problems when baking ? 

and when exactly  decide to share uv, when dealing with baking normal ?



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P2 : 


in this image which one will give you better result A or B ?

and is there a rule to decide between a or b ? 


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P3


and last one which one A or B ? with reason   

thanks

Klo Works

I bake to test the sharing 


on left is separate uv on right is share uv


here the sharing area

so I was wondering is it a good way to do this or better to avoid the sharing. 
is it gonna be problem in engine? is it better just share if got symmetrical and not like my example .

huffer

You can definitely share that UV space, but keep in mind how is the texture going to look, if it's something like a chipped paint wood, the repetition might be visible. You can have three or more unique instead of all of them and mix them around. For P2, I usually flatten the strip, if you keep it round, if your map will be low res, some antialiasing artifacts might be visible, plus straightened it's easier to make your UV layout. And for P3, B is also good, unless the shape is too conical, as you'd get too much distortion..but depends, in your case it might be ok if it's flattened. Also depends on the final texture (if you have details like text or something that will look bad stretched).

Klo Works

huffer said:

You can definitely share that UV space, but keep in mind how is the texture going to look, if it's something like a chipped paint wood, the repetition might be visible. You can have three or more unique instead of all of them and mix them around. For P2, I usually flatten the strip, if you keep it round, if your map will be low res, some antialiasing artifacts might be visible, plus straightened it's easier to make your UV layout. And for P3, B is also good, unless the shape is too conical, as you'd get too much distortion..but depends, in your case it might be ok if it's flattened. Also depends on the final texture (if you have details like text or something that will look bad stretched).

Thanks alot  for answering, 

You can definitely share that UV space, but keep in mind how is the texture going to look, if it's something like a chipped paint wood, the repetition might be visible. You can have three or more unique instead of all of them and mix them around

ok so sharing like this will be fine when doing baking normal ? 

 For P2, I usually flatten the strip, if you keep it round, if your map will be low res, some antialiasing artifacts might be visible, plus straightened it's easier to make your UV layout.

so it depends on the polycount if it low res like 8 polygon, then I  use P2: B method. round not flatten it.

And for P3, B is also good, unless the shape is too conical, as you'd get too much distortion..but depends, in your case it might be ok if it's flattened. Also depends on the final texture (if you have details like text or something that will look bad stretched).

yeah I try to use text  




"A" method better result than "B" the text got some distortion , I will use substance painter so it will be easy to put the text.



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P4 : 


in this I will use flatten since not too low and its not big object small tv screen so the distortion not noticeable.