According to the specification, if array number == 0 and faces == 6 then image size contains size of a single face, this case is not processed in the Textures iterator.

To fix this, you need to multiply image size by 6, if current file is cubemap.

Currently the function ktx::Ktx::new panics if an invalid file is provided:

fn main() {
    unsafe {
        ktx::Ktx::new(std::fs::read("/home/fctorial/.zshrc").unwrap());
    }
}

What should I do if I'm trying to load an unknown ktx file, for example, a file that I'm receiving over the network. Is there another function that returns an std::error::Error if the provided file is invalid? Does the library currently perform sanity checks on the input file (pixel_height == 0 && pixel_depth != 0 is invalid, numArrayLayers must be zero for 3d images, cubemaps must be 2d)?

I'm considering adding support for generating ktx files in version 2.0 of the squish-rs example cli utility and this crate looks like a perfect match. Do you have any plans for write support? I can help out with the implementation if necessary but don't know if I have enough time/energy to write such a thing entirely by myself.

Looking at the current docs, I would also appreciate a bit of refactoring for an API that resembles that of the ddsfile crate more, especially wrt having enums instead of u32 for format selection (maybe with Into implementations for convenience's sake) etc.

Image data section of ktx files is designed to be directly uploaded to the gpu, allowing users to create an image with a simple memcpy.

libktx example:
https://github.com/KhronosGroup/Vulkan-Samples/blob/b3e8d49dcc2f94f4a14cafb64f02d1dca71c9565/samples/api/texture_loading/texture_loading.cpp#L150

Ktx objects created using this crate do not allow the users to access the raw image data, making this impossible.

As title.

Currently, the implementation assumes a KTX version of 1.1 and fails to parse with a panic (not even an error — an unrecoverable panic) if the texture is a KTX 2.0 file. The latest KTX 2.0 specification is available here.

This code causes a segmentation fault:

fn main() {
    let ktx_bytes = std::fs::read(local_file!("street.ktx")).unwrap();
    let texture = ktx::Ktx::new(ktx_bytes.as_slice());
    for data in texture.textures() {
        trace!(data.len());
    }
    trace!(texture);
}

streets.ktx: https://github.com/KhronosGroup/Vulkan-Samples-Assets/blob/177aea4beaa264e6e9823c80d9d0460e61db222f/textures/uffizi_rgba16f_cube.ktx