Added Brush support. Modified structs. Fixed client time.

- Brushes are now supported and can be included with a SlateBrush.
- The variables in PenData and LineData structs have been changed.
- Added internal function to the widget to draw rotated boxes.
- Lines are assigned time when replicated so they decay correctly.
- Fixed culling settings in the Canvas Manager. Now you can set 1 culling method instead of an all or nothing.

Author: Cutter-H

Content/CanvasManagerSettings.uasset

@@ -16,14 +16,17 @@
 #include "Curves/CurveFloat.h"
 #include "GameFramework/PlayerState.h"
 #include "Kismet/GameplayStatics.h"
+#include "Slate/SlateBrushAsset.h"
 
 
 void UReplicatedCanvasWidgetBase::DrawLines(FPaintContext& context) const{
+	FVector2D currentPos = FVector2D::ZeroVector;
+	FVector2D lineDirection = FVector2D::ZeroVector;
 	for (const FCanvasLineData& line : LineData) {
 		 if(ShouldDrawLine(line)) {
 		 	FLinearColor color(line.PenData.Tint);
 		 	const float lineLife = line.GetLineLifetime(GetWorld());
-		 	float size = line.PenData.Size;
+		 	float sizeScalar = 1.f;
 		 	if (FadeDuration > 0 && EraseTime > 0 && lineLife > (EraseTime - FadeDuration)) {
 		 		const float fadeAmount =  ( (EraseTime - lineLife) / FadeDuration);
 
@@ -43,18 +46,40 @@ void UReplicatedCanvasWidgetBase::DrawLines(FPaintContext& context) const{
 		 		/* Size Fade */ {
 		 			const auto sizeFadeType = line.PenData.SizeFadeType;
 		 			if (sizeFadeType == EPenDataFadeType::PENFADETYPE_Linear) {
-		 				size *= fadeAmount;
+		 				sizeScalar *= fadeAmount;
 		 			}
 		 			if (sizeFadeType == EPenDataFadeType::PENFADETYPE_Curve) {
 		 				if (line.PenData.SizeFadeCurve) {
-		 					size *= FMath::Abs(line.PenData.SizeFadeCurve->GetFloatValue(1-fadeAmount));
+		 					sizeScalar *= FMath::Abs(line.PenData.SizeFadeCurve->GetFloatValue(1-fadeAmount));
 		 				}
 		 			}
 
 		 		}
 		 	}
-		 	UWidgetBlueprintLibrary::DrawSpline(context, line.StartingPoint, line.StartingDirection, line.StoppingPoint, line.StoppingDirection, color, size);
-		
+		 	if (line.PenData.Brush) {
+		 		const FVector2D brushSize = line.PenData.BrushSize * sizeScalar;
+		 		currentPos = line.StartingPoint;
+		 		lineDirection = (line.StoppingPoint - currentPos).GetSafeNormal();
+		 		float rotationAngle = 0.f;
+		 		if (line.PenData.bBrushFollowsLine) {
+		 			rotationAngle = FMath::RadiansToDegrees(FMath::Atan2(lineDirection.X, -lineDirection.Y));
+		 			while (rotationAngle < 0.f) { rotationAngle += 360.f; }
+		 			while (rotationAngle > 360.f) { rotationAngle -= 360.f; }
+		 		}
+		 		while (currentPos != line.StoppingPoint) {
+		 			MakeRotatedBrush(context, line.PenData, brushSize, currentPos, rotationAngle);
+		 			if ((currentPos - line.StoppingPoint).Size() <= line.PenData.StepSize) {
+		 				currentPos = line.StoppingPoint;
+		 			}
+		 			else {
+		 				currentPos += lineDirection * line.PenData.StepSize;
+		 			}
+		 		}
+		 		MakeRotatedBrush(context, line.PenData, brushSize, currentPos, rotationAngle);
+		 	}
+		 	else {
+		 		UWidgetBlueprintLibrary::DrawLine(context, line.StartingPoint, line.StoppingPoint, color, false, sizeScalar * line.PenData.LineSize);
+		 	}
 		 }
 	 }
  }
@@ -81,6 +106,21 @@ void UReplicatedCanvasWidgetBase::TrySetupCanvasManager() {
 	}
 }
 
+void UReplicatedCanvasWidgetBase::MakeRotatedBrush(FPaintContext& context, const FCanvasPenData& penData, FVector2D brushSize, FVector2D pos, float rotation) const {
+	context.MaxLayer++;
+	FSlateDrawElement::MakeRotatedBox(
+		context.OutDrawElements,
+	   context.MaxLayer,
+	   context.AllottedGeometry.ToPaintGeometry(brushSize, FSlateLayoutTransform(pos - (brushSize/2))),
+	   &penData.Brush->Brush,
+	   ESlateDrawEffect(penData.DrawEffect),
+	   rotation,
+	   TOptional<FVector2f>(),
+	   FSlateDrawElement::RelativeToElement,
+	   penData.Tint
+   );
+}
+
 void UReplicatedCanvasWidgetBase::NativeConstruct() {
 	Super::NativeConstruct();
 
@@ -132,6 +172,7 @@ FReply UReplicatedCanvasWidgetBase::NativeOnMouseButtonDown(const FGeometry& InG
 }
 
 FReply UReplicatedCanvasWidgetBase::NativeOnMouseMove(const FGeometry& InGeometry, const FPointerEvent& InMouseEvent) {
+	UKismetSystemLibrary::PrintString(this, "We hit");
 	if (ShouldDraw()) {
 
 		FVector2D currentPosition = InGeometry.AbsoluteToLocal( InMouseEvent.GetScreenSpacePosition());
@@ -143,7 +184,7 @@ FReply UReplicatedCanvasWidgetBase::NativeOnMouseMove(const FGeometry& InGeometr
 			currentDirection = InMouseEvent.GetGestureDelta();
 		}
 		if (bStartedDrawing) {
-			const FCanvasLineData line(GetDrawerName(), BoardID, UGameplayStatics::GetTimeSeconds(GetWorld()), LastPosition, LastDirection, currentPosition, currentDirection, PenData);
+			const FCanvasLineData line(GetDrawerName(), BoardID, UGameplayStatics::GetTimeSeconds(GetWorld()), LastPosition, currentPosition, PenData);
 			LineData.Add(line);
 			AddLineToState(line);
 		}
@@ -174,7 +215,7 @@ void UReplicatedCanvasWidgetBase::OnLineAddedToBoard(FName board, const FCanvasL
 		return;
 	}
 	 if (line.DrawingPlayer != GetDrawerName() && BoardID != line.BoardID) {
-	 	LineData.Add(line);
+	 	LineData.Add(FCanvasLineData(line, UGameplayStatics::GetTimeSeconds(GetWorld())));
 	 }
  }
 
@@ -216,7 +257,7 @@ FName UReplicatedCanvasWidgetBase::GetDrawerName_Implementation() {
 
 bool UReplicatedCanvasWidgetBase::ShouldDraw_Implementation() const {
 
-	if (!bWantsToDraw || !(PenData.Size > 0) || !(PenData.Tint.A > 0)) {
+	if (!bWantsToDraw || PenData.HasNoSize() || !(PenData.Tint.A > 0)) {
 		return false;
 	}
 

Source/ReplicatedDrawingWidgetPlugin/Private/Canvas/ReplicatedCanvasWidgetBase.cpp

@@ -18,13 +18,17 @@ UCLASS()
 class REPLICATEDDRAWINGWIDGETPLUGIN_API UReplicatedCanvasWidgetBase : public UUserWidget {
 	GENERATED_BODY()
 
+	
 	// Basically a tick function that draws lines.
 	void DrawLines(FPaintContext& context) const;
 	// Tick function that deletes unused lines outside the EraseTime. 
 	void CleanupLines();
 	/* Tick function that attempts to set up maanger. If it's already set this does nothing. ONLY ONE CANVAS MANAGER SHOULD BE USED PER MAP. */
 	void TrySetupCanvasManager();
-	
+
+
+	//
+	void MakeRotatedBrush(FPaintContext& context, const FCanvasPenData& penData, FVector2D brushSize, FVector2D pos, float rotation) const;
 	bool bWantsToDraw = false;
 	bool bStartedDrawing = false;
 	TArray<FCanvasLineData> LineData;

Source/ReplicatedDrawingWidgetPlugin/Private/Canvas/ReplicatedCanvasWidgetBase.h

@@ -60,8 +60,13 @@ void AReplicatedCanvasManager::CleanLines() {
 	}
 
 	for (FReplicatedCanvasData& board : Boards) {
-		while (board.Lines.Num() > 0 && (board.Lines.Num() > MaxNumberOfLines || board.Lines[0].GetLineLifetime(GetWorld()) > MaxLineDuration)) {
-			board.Lines.RemoveAt(0);
+		
+		while (board.Lines.Num() > 0) {
+			const bool timeCull = MaxLineDuration > 0 ? board.Lines[0].GetLineLifetime(GetWorld()) > MaxLineDuration : false;
+			const bool numCull = MaxNumberOfLines > 0 ? board.Lines.Num() > MaxNumberOfLines : false;
+			if (timeCull || numCull) {
+				board.Lines.RemoveAt(0);
+			}
 		}	
 
 	}	

Source/ReplicatedDrawingWidgetPlugin/Private/CanvasHelpers/ReplicatedCanvasManager.cpp

@@ -18,16 +18,35 @@ enum EPenDataFadeType : uint8 {
 	PENFADETYPE_Curve = 2 UMETA(DisplayName = "Curve"),	
 };
 
+UENUM(BlueprintType)
+enum class EPenDrawEffect : uint8 {
+	/** No effect applied */
+	PENEFFECT_None = 0 UMETA(DisplayName = "None"),
+	/** Advanced: Draw the element with no blending */
+	PENEFFECT_NoBlending = 1 << 0 UMETA(DisplayName = "No Blending"),
+	/** Advanced: Blend using pre-multiplied alpha. Ignored if NoBlending is set. */
+	PENEFFECT_PreMultipliedAlpha = 1 << 1 UMETA(DisplayName = "Pre-Multiplied Alpha"),
+	/** Advanced: No gamma correction should be done */
+	PENEFFECT_NoGamma = 1 << 2 UMETA(DisplayName = "No Gamma"),
+	/** Advanced: Change the alpha value to 1 - Alpha. */
+	PENEFFECT_InvertAlpha = 1 << 3 UMETA(DisplayName = "Invert Alpha"),
+};
 USTRUCT(BlueprintType)
 struct FCanvasPenData {
 	GENERATED_BODY()
 
 	FCanvasPenData() {}
 
 	/* Brush used to draw the line. THIS IS NOT IMPLEMENTED*/
-	UPROPERTY( /* EditAnywhere,  */ BlueprintReadWrite, Category = "Pen")
+	UPROPERTY( EditAnywhere, BlueprintReadWrite, Category = "Pen")
 	TObjectPtr<USlateBrushAsset> Brush = nullptr;
 
+	UPROPERTY( EditAnywhere, BlueprintReadWrite, Category = "Pen")
+	bool bBrushFollowsLine = false;
+
+	UPROPERTY( EditAnywhere, BlueprintReadWrite, Category = "Pen")
+	EPenDrawEffect DrawEffect = EPenDrawEffect::PENEFFECT_None;
+	
 	/* Distance between each stamp of the brush. */
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Pen", meta=(EditCondition = "Brush != nullptr", EditConditionHides))
 	float StepSize = 1.f;
@@ -37,9 +56,13 @@ struct FCanvasPenData {
 	FLinearColor Tint = FColor::White;
 
 	/* Size of the line. */
-	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Pen", meta=(EditCondition = "Brush == nullptr", EditConditionHides))
-	float Size = 1.f;
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Pen", meta=(EditCondition = "Brush != nullptr", EditConditionHides))
+	FVector2D BrushSize = FVector2D::One();
 
+	/* Size of the line. */
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Pen", meta=(EditCondition = "Brush == nullptr", EditConditionHides))
+	float LineSize = 1.f;
+	
 	/* Determines how the opacity fades if the board supports fading. */
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Pen|Fading")
 	TEnumAsByte<EPenDataFadeType> OpacityFadeType = EPenDataFadeType::PENFADETYPE_Linear;
@@ -55,16 +78,20 @@ struct FCanvasPenData {
 	/* A curve that makes the line size decrease if the board fades lines. The value used will be an absolute value of -1 to 1. */
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Pen|Fading", meta=(EditCondition = "SizeFadeType == EPenDataFadeType::PENFADETYPE_Curve", EditConditionHides))
 	TObjectPtr<UCurveFloat> SizeFadeCurve = nullptr;
-	
+
+	bool HasNoSize() const { return Brush != nullptr ? BrushSize.GetMin() <= 0 : LineSize <= 0.f; }
 };
 
 USTRUCT(BlueprintType)
 struct FCanvasLineData {
 	GENERATED_BODY()
 
 	FCanvasLineData() {}
-	FCanvasLineData(FName boardName, int boardID, float time, FVector2D startP, FVector2D startD, FVector2D stopP,  FVector2D stopD, FCanvasPenData penData = FCanvasPenData()) :
-	DrawingPlayer(boardName), BoardID(boardID), DrawnTime(time), StartingPoint(startP), StartingDirection(startD), StoppingPoint(stopP), StoppingDirection(stopD), PenData(penData)
+	FCanvasLineData(const FCanvasLineData& line, float newTime) :
+	DrawingPlayer(line.DrawingPlayer), BoardID(line.BoardID), DrawnTime(newTime), StartingPoint(line.StartingPoint), StoppingPoint(line.StoppingPoint), PenData(line.PenData)
+	{};
+	FCanvasLineData(FName drawerName, int boardID, float time, FVector2D startingPoint, FVector2D stoppingPoint, FCanvasPenData penData = FCanvasPenData()) :
+	DrawingPlayer(drawerName), BoardID(boardID), DrawnTime(time), StartingPoint(startingPoint), StoppingPoint(stoppingPoint), PenData(penData)
 	{};
 
 	/* Player that drew the line. */
@@ -79,19 +106,14 @@ struct FCanvasLineData {
 	/* The starting point of the line. */
 	UPROPERTY(BlueprintReadOnly, Category = "Line")
 	FVector2D StartingPoint = FVector2D::ZeroVector;
-	/* The starting direction the cursor was going when the line was started. */
-	UPROPERTY(BlueprintReadOnly, Category = "Line")
-	FVector2D StartingDirection = FVector2D::ZeroVector;
-	/* Stopping Point of the line. */
+	/* The stopping point of the line. */
 	UPROPERTY(BlueprintReadOnly, Category = "Line")
 	FVector2D StoppingPoint = FVector2D::ZeroVector;
-	/* The stopping direction the cursor was going when the line was started. */
-	UPROPERTY(BlueprintReadOnly, Category = "Line")
-	FVector2D StoppingDirection = FVector2D::ZeroVector;
 	/* Pen data that is used for drawing the line.  */
 	UPROPERTY(BlueprintReadOnly, Category = "Line")
 	FCanvasPenData PenData = FCanvasPenData();
-
+	
 	/* Returns how long since the line has been drawn. */
 	float GetLineLifetime(UObject* worldContext) const;
+	
 };