First, sorry this question isn’t really about GLSL, I’m uncertain what forum is appropriate to my question.
I was recently surprised to notice my Intel system magnifies mipmaps by blending the top two mip levels. In my head I imagine magnification would just “blow up” the top-level image, not involving mipmaps. I don’t subscribe to another forum where I can ask this question, so I’m just curious if anyone can give me a rationale for what it’s doing, and bonus question, is mipmap filtering standardized for GLSL, etc. purposes?
Background: The largest image is 256x256. No matter how close I position the texture it’s about half-and-half, so the largest image for 256 images only ever appears as a ghost overlaid over the first mipmap. If I change the bias setting it introduces shimmering, so it seems like it’s working as intended. (Edited: Both levels are magnified, i.e. neither shows as 1x1 pixels.)