Crash on manual mipmap selection

Reproduction steps:

  • Create or open a material
  • Create a texture sample node
  • Make sure a texture is assigned
  • Set MipValueMode to MipLevel
  • Raise ConstMipLevel to 4 (or higher)
  • Crash

Tested on both version 4.4.3 and the 4.5 preview, the result is the same.

A semi-related note: the tooltip for MipValueMode is wrong. (It talks about noise functions)

Stack trace from 4.5:

Unknown exception - code 00000001 (first/second chance not available)

Assertion failed: Index >= 0 && Index < CodeChunks[MaterialProperty][ShaderFrequency].Num() [File:d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\engine\private\materials\HLSLMaterialTranslator.h] [Line: 1100] 

KERNELBASE + 23544 bytes UE4Editor_Core + 3175412 bytes UE4Editor_Core + 1678104 bytes UE4Editor_Core + 1567474 bytes UE4Editor_Engine + 13408268 bytes UE4Editor_Engine + 13718424 bytes UE4Editor_Engine + 12839290 bytes UE4Editor_MaterialEditor + 432559 bytes UE4Editor_Engine + 13725985 bytes UE4Editor_Engine + 13393826 bytes UE4Editor_Engine + 13397590 bytes UE4Editor_Engine + 13398374 bytes UE4Editor_MaterialEditor + 603793 bytes UE4Editor_MaterialEditor
+ 842389 bytes UE4Editor_MaterialEditor + 723372 bytes UE4Editor_PropertyEditor + 2141808 bytes UE4Editor_PropertyEditor
+ 1984439 bytes UE4Editor_PropertyEditor + 1985507 bytes UE4Editor_PropertyEditor + 2555502 bytes UE4Editor_PropertyEditor
+ 2300536 bytes UE4Editor_PropertyEditor + 1619185 bytes UE4Editor_PropertyEditor + 1637734 bytes UE4Editor_PropertyEditor
+ 1206339 bytes UE4Editor_PropertyEditor + 2590246 bytes UE4Editor_PropertyEditor + 1619571 bytes UE4Editor_PropertyEditor
+ 1638168 bytes UE4Editor_Slate + 2259865 bytes UE4Editor_Slate + 1555272 bytes UE4Editor_Slate + 2267916 bytes UE4Editor_Slate + 815511 bytes UE4Editor_Slate + 751747 bytes UE4Editor_Core + 2506148 bytes UE4Editor_Core + 2450651 bytes UE4Editor_Core + 2511433 bytes UE4Editor_Core + 2439026 bytes user32
+ 9268 bytes user32 + 8855 bytes UE4Editor_Core + 3158278 bytes UE4Editor!FEngineLoop::Tick() + 3106 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\launchengineloop.cpp:2111] UE4Editor!GuardedMain() + 479 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\launch.cpp:133] UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\windows\launchwindows.cpp:125] UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\windows\launchwindows.cpp:201] UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]

Hi Arnage,

Thank you for the report and the clear repro steps. I was able to reproduce this in our latest internal build and our preview of 4.5. I’ve submitted a bug report for this (TTP: 349556).

I have no given time frame for when this will be fixed but once the update is implemented and I can verify it having been fixed I’ll update the post here.

Thank you!

Tim