The index values are round numbers. Checking agaist
the half-values improves robustness against small
floating point delta errors that occur on some GPUs.
By allowing a palette to be copied to an array, a speedup can be gained in HardwarePalette since palettes can be block copied using native magic rather than having to copy them item by item. We transpose the buffer in HardwarePalette in order to allow a contiguous block copy into this buffer, transposing again in the shader to keep everything correct.
- Add separate ImmutablePalette and MutablePalette classes since the distinction is extremely important to HardwarePalette.
- Keep a cache of palettes in HardwarePalette to avoid reallocation them every time ApplyModifiers is called.
- Palettes that are not allowed to be modified are copied to the buffer once when added, rather than every time ApplyModifiers is called.
- The AdjustPalette method now takes a read-only dictionary to prevent the dictionary being messed with.
- Added a constant for the palette size to remove its usage as a magic number in several areas.
- The ColorPreviewManagerWidget is annoying in that it needs to actually permanently update a palette after it has been added. To allow this, HardwarePalette now allows a palette to be replaced after initialization. The WorldRenderer therefore now also updates the PaletteReference it created earlier with the new palette to prevent stale data being used elsewhere.
