Support more style range options

[manthey]

No description provided.

[banesullivan]

remove print statement?

[manthey]

Thanks.

[banesullivan]

I'm curious when full is wanted/needed?

[banesullivan]

I suppose I've had a few float rasters but the data range was always much larger than 255 and thus the tiles would come back looking a single color. Setting full to 1 might still have the same issue?

[manthey]

I'm curious when full is wanted/needed?

The specific use case is that we have a file with multiple images that are conceptually a matrix of channel, z value (altitude), time value, and xy sample position, all in 16-bit uint format. We want to make a max-merge for each distinct combination other than z. When we specify a style like {bands: [{frame: 0}, {frame 5}, {frame 10}]}, if we don't specify the min/max values, they default to auto. But, for 16-bit uint, auto resolves to min/max, whereas we want 0/full-range.

I think this means we either need to introduce a new term to avoid using the current default (hence full) OR make a breaking change.

[manthey]

I suppose I've had a few float rasters but the data range was always much larger than 255 and thus the tiles would come back looking a single color. Setting full to 1 might still have the same issue?

Yes -- this is a problem where data sources don't actually indicate what their valid range is. You can read EVERY pixel and find the min/max, but that is expensive. You can do this at a low resolution (which is what is currently done), which is only a guess. Some datatypes imply a min/max (uint8 -> [0,255], uint16 -> [0,65535]), but some don't (float). Even then, I've seen data in uint16 which is really uint12 or uint14 with the high bits zeroed. I'm not sure we have a decent general solution.

[banesullivan]

All makes sense! Thanks for the explanation!