Lightmass Error Reporting

ambershee · September 14, 2016, 5:57pm

Hello!

Today I encountered a bug wherein a specific mesh in several of our levels had begun to interfere with lightmass and prevent lighting from being built. Lightmass would not long anything regarding this issue, and I would only get a simple generic ‘Swarmagent failed to kick off’ error. It took nearly nine hours to find the issue, and this could have been considerably longer had I not been lucky.

Looking at past threads, this has been a persistent problem for over two years and has tripped up quite a number of people. Whilst this bug is annoying, the real issue is that lightmass is not reporting or logging critical errors, and the error that is reported is somewhat erroneous - this needs to change.

My particular encounter is briefly detailed here - the nine hours lost to debugging the problem could have been reduced to minutes, had lightmass logged the error and reported the offending asset in question. Someone unable to make use of a debugger and sift through lightmass / the swarm agent may not have been able to solve the issue at all.

There are also a selection of other tickets for the same, or similar issues, which could have been greatly aided by better reporting practices in lightmass and the swarmagent. Many of these people never found a solution to their problems. (this is not a complete list, there are more - this is just the first two pages of results in google):

Tim_Hobson · September 14, 2016, 7:21pm

Hi Ambershee,

Ticket has been submitted and can be tracked for status here: Unreal Engine Issues and Bug Tracker (UE-36002)

Thanks!

Tim