- Started working on better editor lines:

- Changed default constructors for FEditorLineData to always consist of at least 2 points.
- Adding lines should work now.

InstancedMeshLines/Plugins/InstancedMeshLineRendering/Source/InstancedMeshLineRendering/Private/GPUInstancedLineComponent.cpp

@@ -101,14 +101,30 @@ void UGPUInstancedLineComponent::Init()
 	CurrentTextureMarker = FIntPoint(0, 0);
 	ClearInstances();
 
+	RegisterSerializedEditorLines();
+
 	bIsInitialized = true;
 
-	// Add serialized lines to be rendered immediately - pretty sure this could and should be done differently.
+	//// Add serialized lines to be rendered immediately - pretty sure this could and should be done differently.
+	//for (FEditorLineData& EditorLine : EditorLines)
+	//{
+	//	AddLineFromEditorData(EditorLine);
+	//}
+	
+}
+
+void UGPUInstancedLineComponent::RegisterSerializedEditorLines()
+{
+
+	// Here's to hoping the respective id field doesn't get serialized...
+
 	for (FEditorLineData& EditorLine : EditorLines)
+	{
+		if(EditorLine.RespectiveLineId == -1)
 		{
 			AddLineFromEditorData(EditorLine);
 		}
-	
+	}	
 }
 
 FUpdateTextureRegion2D* UGPUInstancedLineComponent::CalculateTextureRegions(const FIntPoint& StartIndex,
@@ -173,6 +189,9 @@ void UGPUInstancedLineComponent::BeginPlay()
 {
 	Super::BeginPlay();
 
+	// todo don't think this is needed here
+	RegisterSerializedEditorLines();
+	
 	//Init();
 	if(!bIsInitialized)
 	{
@@ -196,8 +215,15 @@ void UGPUInstancedLineComponent::PostEditChangeChainProperty(FPropertyChangedCha
 	{
 		if (PropertyChangedEvent.Property->GetFName() == GET_MEMBER_NAME_CHECKED(UGPUInstancedLineComponent, EditorLines))
 		{
-			if (PropertyChangedEvent.ChangeType == EPropertyChangeType::ArrayAdd
-				|| PropertyChangedEvent.ChangeType == EPropertyChangeType::Duplicate)
+			// A new entry has been added
+			if (PropertyChangedEvent.ChangeType == EPropertyChangeType::ArrayAdd)
+			{
+				const int32 AddedAtIndex = PropertyChangedEvent.GetArrayIndex(PropertyChangedEvent.Property->GetFName().ToString());
+				check(AddedAtIndex != INDEX_NONE);
+				AddLineFromEditorData(EditorLines[AddedAtIndex]);
+			}
+			// An entry has been duplicated
+			else if (PropertyChangedEvent.ChangeType == EPropertyChangeType::Duplicate)
 			{
 				const int32 AddedAtIndex = PropertyChangedEvent.GetArrayIndex(PropertyChangedEvent.Property->GetFName().ToString());
 				check(AddedAtIndex != INDEX_NONE);
@@ -208,6 +234,7 @@ void UGPUInstancedLineComponent::PostEditChangeChainProperty(FPropertyChangedCha
 				const int32 RemovedAtIndex = PropertyChangedEvent.GetArrayIndex(PropertyChangedEvent.Property->GetFName().ToString());
 				check(RemovedAtIndex != INDEX_NONE);
 
+				RemoveLine(EditorLines[RemovedAtIndex].RespectiveLineId); // todo test me, depends on if the data was removed already or not
 			}
 			else if (PropertyChangedEvent.ChangeType == EPropertyChangeType::ArrayClear)
 			{
@@ -221,6 +248,14 @@ void UGPUInstancedLineComponent::PostEditChangeChainProperty(FPropertyChangedCha
 				check(SetValueAtIndex != INDEX_NONE);
 			}
 		}
+		else if (PropertyChangedEvent.Property->GetName() == "X" || PropertyChangedEvent.Property->GetName() == "Y" || PropertyChangedEvent.Property->GetName() == "Z")
+		{
+			if (PropertyChangedEvent.ChangeType == EPropertyChangeType::ValueSet)
+			{
+
+			}
+
+		}
 		else if (PropertyChangedEvent.Property->GetFName() == "TextureWidth")
 		{
 
@@ -340,8 +375,8 @@ int32 UGPUInstancedLineComponent::AddLine(const TArray<FVector>& Line, FLinearCo
 {
 	if (Line.Num() < 2)
 	{
-		UE_LOG(LogTemp, Error, TEXT("UGPUInstancedLineComponent::AddLine : Can't add line with less than 2 points."));
-		return 0;
+		UE_LOG(LogTemp, Error, TEXT("UGPUInstancedLineComponent::AddLine : Can't add line with less than 2 points.")); // Actually we can!
+		return -1;
 	}
 	// 1.
 	GPULineArray& NewLineArray = LineMap.Add(NextFreeId, GPULineArray());
@@ -350,6 +385,8 @@ int32 UGPUInstancedLineComponent::AddLine(const TArray<FVector>& Line, FLinearCo
 	const int32 LineId = NextFreeId;
 	NextFreeId++; // TODO Fix Id system as this can possibly overflow.
 
+
+		
 	const int32 NumberSegments = Line.Num() - 1;
 	
 	const FIntPoint InitialTextureMarker = CurrentTextureMarker;
@@ -373,9 +410,6 @@ int32 UGPUInstancedLineComponent::AddLine(const TArray<FVector>& Line, FLinearCo
 	MoveTextureMarker();
 	CurrentTextureIndex++;
 
-	// The line is longer than the remaining space on the row of the texture, so we need to update more than just one row.
-	const bool bMultiRow = InitialTextureMarker.Y != CurrentTextureMarker.Y;
-
 	// Recreate the data on the heap to allow asynchronous texture update.
 	TArray<FVector4>* TextureData = new TArray<FVector4>(Line);
 	// "Mark" the first entry with w=0 as first segment of the line, and the last with w=-1
@@ -420,6 +454,8 @@ bool UGPUInstancedLineComponent::AddPoint(int32 LineId, const FVector& Point)
 
 	// Get color and width of the line
 	GPULineArray& Line = LineMap[LineId];
+
+	
 	const float R = PerInstanceSMCustomData[Line[0].Key * NumCustomDataFloats];
 	const float G = PerInstanceSMCustomData[Line[0].Key * NumCustomDataFloats + 1];
 	const float B = PerInstanceSMCustomData[Line[0].Key * NumCustomDataFloats + 2];

InstancedMeshLines/Plugins/InstancedMeshLineRendering/Source/InstancedMeshLineRendering/Public/GPUInstancedLineComponent.h

@@ -31,6 +31,7 @@ struct FEditorPoint
 
 	FEditorPoint()
 	{
+		Point = FVector(0, 0, 0);
 	}
 
 	FEditorPoint(const FVector& InPoint)
@@ -49,7 +50,7 @@ struct FEditorLineData
 	TArray<FEditorPoint> Points;
 
 	UPROPERTY(EditAnywhere)
-	float Width;
+	float Width = 2.0;
 
 	UPROPERTY(EditAnywhere)
 	FColor Color;
@@ -58,13 +59,19 @@ struct FEditorLineData
 	
 	FEditorLineData()
 	{
+		Points.SetNumZeroed(2);
+		Width = 2.0f;
+		Color = FColor::Red;
 	}
 
 	FEditorLineData(const TArray<FVector>& InPoints, float InWidth, const FColor& InColor)
 		: Points(InPoints), Width(InWidth), Color(InColor)
 	{
+		if(Points.Num() < 2)
+		{
+			Points.SetNumZeroed(2);
+		}
 	}
-
 };
 
 
@@ -90,6 +97,8 @@ private:
 
 	void Init();
 
+	void RegisterSerializedEditorLines();
+
 	FUpdateTextureRegion2D* CalculateTextureRegions(const FIntPoint& StartIndex, int32 NumberOfPoints, int32& NumberOfRegionsOut);
 
 	GPULinesMap LineMap;