3.1.1 fixes two things a texture pack got wrong on screen. Nothing else changes; if 3.1.0 was working for you without a pack, so is this.
Fixed
- Textures no longer flicker back to the original as you move. A replacement image was decoded once and then forgotten, so every time the renderer's texture cache turned over - a prop coming into view, a room with a lot on screen, the same texture in two models - the game drew its own texture for a frame and decoded the pack's again. With PD Plus that was textures popping between the two all the way through a stage, and one case that never settled at all. Decoded images are now kept, so a texture that has been seen once stays the pack's.
- A few textures were stretched or cropped. The N64 pads a texture's rows out to whole lines, and the port draws the padded row; a pack built for an emulator draws only the texture itself. On the 278 PD Plus textures whose width is not a multiple of the line, the image was pulled across the padding and the right edge of it was cut off. Those images are now put back onto the padded row before they are drawn.
Added
Mod.TexturePackCacheMBinpd.ini(under[Mod]) is how much memory decoded pack textures may hold, 512 by default. PD Plus is about 2.2GB fully decoded, so the least recently drawn are let go past the budget and decoded again if they come back. Raise it if you have the memory and a large pack.