Was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below.
Error message:
Assertion failed: Mips.Num() > 0 [Link Removed] [Line: 1255]
Source Context:
1245 {
1246 break;
1247 }
1248 }
1249
1250 return NumNonStreamingMips;
1251 }
1252 else
1253 {
1254 check(Mips.Num() > 0);
1255 int32 MipCount = Mips.Num();
1256 int32 NumNonStreamingMips = 1;
1257
1258 // Take in to account the min resident limit.
1259 ***** NumNonStreamingMips = FMath::Max(NumNonStreamingMips, UTexture2D::GetMinTextureResidentMipCount());
1260 NumNonStreamingMips = FMath::Min(NumNonStreamingMips, MipCount);
1261 int32 BlockSizeX = GPixelFormats[PixelFormat].BlockSizeX;
1262 int32 BlockSizeY = GPixelFormats[PixelFormat].BlockSizeY;
1263 if (BlockSizeX > 1 || BlockSizeY > 1)
1264 {
1265 NumNonStreamingMips = FMath::Max<int32>(NumNonStreamingMips, MipCount - FPlatformMath::FloorLog2(Mips[0].SizeX / BlockSizeX));
1266 NumNonStreamingMips = FMath::Max<int32>(NumNonStreamingMips, MipCount - FPlatformMath::FloorLog2(Mips[0].SizeY / BlockSizeY));
1267 }
1268
1269 return NumNonStreamingMips;
1270 }
1271 }
1272
1273 #if WITH_EDITOR
1274 bool FTexturePlatformData::AreDerivedMipsAvailable() const
Most recent user affected CL: 3348071
Logs: non available
Issue call stack shares some similarities with this Jira: [Link Removed]
CrashReporter User Descriptions:
Unable to reproduce
UE4Editor_Engine!FTexturePlatformData::GetNumNonStreamingMips() [texturederiveddata.cpp:1260] UE4Editor_Engine!SerializePlatformData() [texturederiveddata.cpp:1356] UE4Editor_Engine!FTexturePlatformData::SerializeCooked() [texturederiveddata.cpp:1395] UE4Editor_Engine!UTexture::SerializeCookedPlatformData() [texturederiveddata.cpp:1981] UE4Editor_Engine!UTexture2D::Serialize() [texture2d.cpp:210] UE4Editor_CoreUObject!FArchiveSaveTagExports::ProcessTaggedObjects() [savepackage.cpp:1092] UE4Editor_CoreUObject!FPackageExportTagger::TagPackageExports() [savepackage.cpp:3362] UE4Editor_CoreUObject!UPackage::Save() [savepackage.cpp:4069] UE4Editor_UnrealEd!UEditorEngine::Save() [editorengine.cpp:4177] UE4Editor_UnrealEd!UCookOnTheFlyServer::SaveCookedPackage() [cookontheflyserver.cpp:2903] UE4Editor_UnrealEd!UCookOnTheFlyServer::TickCookOnTheSide() [cookontheflyserver.cpp:1995] UE4Editor_UnrealEd!UCookCommandlet::NewCook() [cookcommandlet.cpp:1582] UE4Editor_UnrealEd!UCookCommandlet::Main() [cookcommandlet.cpp:868] UE4Editor_Cmd!FEngineLoop::PreInit() [launchengineloop.cpp:2005] UE4Editor_Cmd!GuardedMain() [launch.cpp:127] UE4Editor_Cmd!GuardedMainWrapper() [launchwindows.cpp:134] UE4Editor_Cmd!WinMain() [launchwindows.cpp:210] UE4Editor_Cmd!__scrt_common_main_seh() [exe_common.inl:264] kernel32!BaseThreadInitThunk() ntdll!RtlUserThreadStart()
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