Editor Crash: DebugDrawPoint in FAsyncTask

[anonymous_user_af553a2a]

Hi together,

during Recast creates the NavMesh-Tiles i call a method in a custom AActor to analyse data during NavMesh-creation. Tiles are created with FAsyncTask(s)/FRecastTileGeneratorTask.

Now i wanted to debug-draw information i get during this process. But as soon as i try to DebugDrawPoint the editor crashes. And i am not sure why… Below is the method causing the crash and a Screenshot to show where it crashes. Everything compiles fine though.

Thanks in advance,

void ARecastHeightfieldProcessor::ProcessHeightfield(rcCompactHeightfield& RasterContext)
{
    UE_LOG(LogTemp, Warning, TEXT("ProcessHeightfield called in subclass"));
    
    const rcCompactHeightfield* chf = &RasterContext;
    const int32 w = chf->width;
    const int32 h = chf->height;
    
    const float cs = chf->cs;
    const float ch = chf->ch;
    
    uint32 partId = 1;
    
    for (int32 y = 0; y < h; ++y) {
        for (int32 x = 0; x < w; ++x) {
            const float fx = chf->bmin[0] + x*cs;
            const float fz = chf->bmin[2] + y*cs;
            const rcCompactCell& c = chf->cells[x+y*w];
            for (int32 i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i) {
                if (chf->areas[i] == RC_NULL_AREA) continue;
                
                const rcCompactSpan& s = chf->spans[i];
                const float fy = chf->bmin[1] + (s.y+1)*ch;
                
                partId +=1;
                
                
                const FVector v0 = FVector(fx, fy, fz);
                const FVector v1 = FVector(fx, fy, fz+cs);
                const FVector v2 = FVector(fx+cs, fy, fz+cs);
                const FVector v3 = FVector(fx+cs, fy, fz);
                
                
                // Causes the crash
                DrawDebugPoint(
                               GetWorld(),
                               v0,
                               10,                  //size
                               FColor(255,0,255),   //pink
                               false,               //persistent (never goes away)
                               0.03 				//point32 leaves a trail on moving object
                               );
            }
        }
    }
    
    UE_LOG(LogTemp, Warning, TEXT("n Parts %d") ,partId);
}

[anonymous_user_af553a2a]

You are absolutely right. This will be the problem. I looked into the threading documentation and they explicitly urge not to DebugDrawX on any other thread than the game thread and NavMesh-generation definitely does not run on the game thread If you`ll write an answer i will accept it.