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 https://github.com/NikLever/threejs-cookbook/blob/380fc21eae44088b54dcc196286d51c9fa20839c/libs/Image2LUT.js . 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.
Added this as a pull request NiksFeatures by NikLever · Pull Request #26880 · mrdoob/three.js · GitHub