Engine Hunk Overflow

What Does It Mean?

Engine Error

This is an engine error message that occurs when attempting to load the map in-game. This is typically related to Lightmap values being modified to an odd value.

What Is Hunk Allocation

This is described as the memory allocated for light data.

• 0 = to normal "program memory" with alloc
• 1 = to Valve's seemingly limited to certain size "MemoryStack memory" with Hunk_Alloc

How To Fix

• +r_hunkalloclightmaps 0
  • Put this in your launch options. This will eliminate the error altogether, but it's not a solution for multiplayer games because it forces the server to put it in their command line options (and many will not do this).
• Find faces with odd or extreme lightmap values.
  • Very large displacements can cause this error. The lightmap value can automatically change (sometimes, to an undesired value). Try splitting them up or making sure the scale on them is not extremely small/big. Having the displacement be very stretched in one dimension can also cause it.^[confirm]
  • If you can't find any lightmap values that seem odd, as a last resort, select the entire map, open the face edit sheet and put 16 for the lightmap scale.