Here are the rest of the transparency modes.
// Transparency Modes
// 0 - first-phase no alpha
// 1 - first-phase with alpha masking
// 2 and 3 - second-phase which overlaps solid geometry
// 4 - alpha test (only render beyond 0x000000CF alpha values)
// 5 - water line object (seperates depth sort automatically)
// 6 - combination of 3 and 4 (second phase render with alpha blend AND alpha test, used for fading LOD leaves)
// 7 - very early draw phase no alpha
Maybe try 6.
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