diff options
| -rw-r--r-- | indra/llinventory/llsettingswater.cpp | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/indra/llinventory/llsettingswater.cpp b/indra/llinventory/llsettingswater.cpp index 90f99e8198..ce6b4a6430 100644 --- a/indra/llinventory/llsettingswater.cpp +++ b/indra/llinventory/llsettingswater.cpp @@ -290,6 +290,19 @@ F32 LLSettingsWater::getModifiedWaterFogDensity(bool underwater) const if (underwater && underwater_fog_mod > 0.0f) { underwater_fog_mod = llclamp(underwater_fog_mod, 0.0f, 10.0f); + // BUG-233797/BUG-233798 -ve underwater fog density can cause (unrecoverable) blackout. + // raising a negative number to a non-integral power results in a non-real result (which is NaN for our purposes) + // Two methods were tested, number 2 is being used: + // 1) Force the fog_mod to be integral. The effect is unlikely to be nice, but it is better than blackness. + // In this method a few of the combinations are "usable" but the water colour is effectively inverted (blue becomes yellow) + // this seems to be unlikely to be a desirable use case for the majority. + // 2) Force density to be an arbitrary non-negative (i.e. 1) when underwater and modifier is not an integer (1 was aribtrarily chosen as it gives at least some notion of fog in the transition) + // This is more restrictive, effectively forcing a density under certain conditions, but allowing the range of #1 and avoiding blackness in other cases + // at the cost of overriding the fog density. + if(fog_density < 0.0f && underwater_fog_mod != (F32)llround(underwater_fog_mod) ) + { + fog_density = 1.0f; + } fog_density = pow(fog_density, underwater_fog_mod); } return fog_density; |