Color displays as black if Horizon color is too low

[ABelliqueux]

If Far color / Horizon color is < 100 (0.10 in blender), the corresponding channel color will display as black.

Example level0.c file :

CVECTOR level0_BGc = { 100, 218, 216, 0 };

results in :

CVECTOR level0_BGc = { 0, 218, 216, 0 };

Might be an error in the linear to RGB conversion function.

Also could be due to psyq dpq calculation. See LibRef47.pdf, p.450 and LibOver47.pdf, p.133, "Light Source Calculation" :

LLM == Local Light Matrix
LLV  == Local light vector
LC    == Local Color
BK   == Back Color
FC   == Far Color
p     == interpolation coefficient

LLV = LLM * v0
LC = BK + LCM * LLV
v2 = (1 - p) * v1 * LC + p * FC

v0 -> vx, vy, vz
vl -> r, g, b
p
NormalColorDpq(): v2 -> r, g, b

[ABelliqueux]

BG and BK colors now haw a minimal value of 63 : ABelliqueux/blender_io_export_psx_mesh@67d9d3a

This + 800be60 should make for more comparable colors.