I would like to know why many instructor talk about 0 to 1 space in UV mapping or related areas of UV unwrapping.
Are 0 to 1 values part of a Boolean, or some programming stuff?
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It is actually a coordinate system in percentage of image size.
A coordinate [0,0] corresponds the lower left corner, and [1,1] is the upper right corner (depending the the render engine/software.
It is made in such way that unwrapping is actually image size independent, so that if at a later time, you decide to use a differently sized image or an image with different proportions the UV map still works, and adapts by stretching over (possibly introducing distortions) to the new image size.
Image textures used are however expected to maintain proportions, so if you switch from say a square image to a rectangular one, your existing UV map will appear stretched. See How to disable the automatic UV stretching after an image size is changed? on how to correct distortions.
It is not a Boolean value nor is it limited to the 0~1 range, it is a float and can take on any value like -3.2, or 158.56.
The image will tile infinitely in X and Y axis repeating at every 1 unit, so for values bellow 0 or above 1 it will tile the image so that coordinate [2,2] will show the same part of the image as [1,1].
Duarte Farrajota Ramos
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Per image? for example every single Uv space has this limitation , is like an array? or bidimentional ? ok... I think is not complicated and that is a concept , any trick or consideration about to know? – RG1988 Nov 07 '16 at 03:13
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Yes, its a percentage per image, but it is not limited to 0-1, it is a float value, and can take on values larger 1, i will simply repeat the image infinitely. Edited and detailed answer above. – Duarte Farrajota Ramos Nov 07 '16 at 03:29
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ok , I think is not more to tell , for cg artist is more than enough to take this few concepts. thanks – RG1988 Nov 07 '16 at 03:32