GdalType as Pulic

[austinstig]

I would like to be able to write a function that loads a raster dataset into an ndarray. For instance:
fn read_as_array<T: Copy + From<GdalType>, P: AsRef<Path>>(path: P) -> Result<ndarray::Array2<T>> { ... }

This would internally coerce the GdalType values into their corresponding primitive number type. Unfortunately, GdalType is currently marked private and this is not possible. Would it be possible to mark it as pub or am I approaching this problem incorrectly?

[jdroenner]

I'm not really sure if we want GdalType to be public. Let me think about the implications :)

[jdroenner]

Since Array2 is the obvious data-structure for raster data, i guess we should add such method directly to rust-gdal. However, we should use a feature "ndarray" to allow disabling.

Do you think this would work for your use-case?

[austinstig]

yes... that would be really great!

[jdroenner]

Great :) If you already have a matching method feel free to create a pull request. Otherwise i will see if i have time to write something :)

[austinstig]

No problem. I'll work on it.

[austinstig]

Not sure how great it is but I have submitted PR. Thanks!

[jdroenner]

Great! thank you :) I will look at it as soon as possible (when i have some free time).

[njwilson23]

I have another use case that I think would benefit from GdalType being public. I'm trying to write a function that, given a sequence of bands, combines them into a dataset.

Since the GDAL data type isn't part of the RasterBand type, I think I need to hard-code the band type in the caller. I think the signature might look something like

fn combine<T: GdalType>(b1: &RasterBand, b2: &RasterBand, ...) -> Result<Dataset, Error>

Is there an alternative that I should consider?

[jdroenner]

Since the GdalDatatatype in gdal-sys is pub, GdalType can probably also be pub. Do you want to create a pull request?