LUTpass from png image

When using the LutPass post-processing filter. What is the recommended way to use a PNG image where the image blocks are horizontal?

I was a little surprised that a horizontal png or jpeg image couldn’t be used with the LUTPass post-processing shader. Images like this are often found. Or sometimes the blocks are packed into a square. I wrote a loader if anyone needs it . To see how to use it download the repo GitHub - NikLever/threejs-cookbook and open index.html using a web server such as Live Server for VSCode. Follow the link post-processing>lut>complete

You can maybe use the texture.rotation and texture.repeat parameters on the LUT texture to change its orientation?
Or load it as an image and rotate it / draw it onto a canvas, then use a CanvasTexture of that canvas as your source for the lut?

I used a canvas and canvas transforms to orientate the image and getImageData to access the pixel data to create the LUT.

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Added this as a pull request NiksFeatures by NikLever · Pull Request #26880 · mrdoob/three.js · GitHub