This function is used to color impact particles.
On Linux I've noticed that this function sometimes is not successful on
retrieving the surface color, leaving an odd color to render the
particles with. The engine function TraceLineMaterialAndLighting() even
has a boolean return value indicating success.
GetModelMaterialColorAndLighting() does not though, but I still observe
failures (the color parameter is not modified). The color is initialized
with an invalid value. If it detects that retrieving the color failed
(engine function said so or the invalid value was left in place), this
now hamfistedly assumes a lightish grey color, but at least still
correctly (presumably) incorporates lighting information.
When this situation is detected, a warning is also printed to the
console. Because why not.
