This error occurred while I was editing the map file.
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ASSERT
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Assertion Failed!
C:\Develop\mb3\Source\Engine\Rgl\rglTerrain.cpp:781
Expression: vista_record_.tileset_ != nullptr
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ASSERT
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Assertion Failed!
C:\Develop\mb3\Source\Engine\Rgl\rglTerrain.cpp:781
Expression: vista_record_.tileset_ != nullptr