Implemented DomeDisplayComponent that uses ProceduralMeshComponent to produce...

Implemented DomeDisplayComponent that uses ProceduralMeshComponent to produce a Dome Mesh with UV-mapping. Also added materials for the dome display, still a test texture and no video. Tangents are yet not computed for the vertices, might need to create multiple points at the top to get proper tangents.

Source/DomeViewerVR/DomeViewerVR.cpp

@@ -4,3 +4,5 @@
 #include "Modules/ModuleManager.h"
 
 IMPLEMENT_PRIMARY_GAME_MODULE( FDefaultGameModuleImpl, DomeViewerVR, "DomeViewerVR" );
+
+DEFINE_LOG_CATEGORY(DomeViewer);

Source/DomeViewerVR/DomeViewerVR.h

@@ -4,3 +4,4 @@
 
 #include "CoreMinimal.h"
 
+DECLARE_LOG_CATEGORY_EXTERN(DomeViewer, Verbose, All);

Source/DomeViewerVR/Private/DomeDisplayComponent.cpp

-// Fill out your copyright notice in the Description page of Project Settings.
+// Copyright 2019 Patric Ljung
+// Linkoping University, Media and Information Technology, Visualization Center C
+// License: BSD-3-Clause (https://opensource.org/licenses/BSD-3-Clause)
 
 
 #include "DomeDisplayComponent.h"
+#include "Math/UnrealMath.h"
+#include "DomeViewerVR.h" // For the log category
 
+//UDomeDisplayComponent::UDomeDisplayComponent(const FObjectInitializer & ObjectInitializer)
+//: Super(ObjectInitializer)
+//{
+//    Radius = 750.0f;
+//    TiltAngle = 27.0f;
+//    HemisphereDegrees = 170.0f;
+//    MeshEdgeDegrees = 3.6f;
+//    Material = nullptr;
+//
+//    BuildDomeMesh();
+//
+//    bUseComplexAsSimpleCollision = true; // Since it is concave
+//
+//    CreateMeshSection(0, MeshVerts, MeshTris, MeshNormals, MeshUVs, MeshColors, MeshTangents, true);
+//}
+
+UDomeDisplayComponent::UDomeDisplayComponent()
+{
+    Radius = 750.0f;
+    TiltAngle = 27.0f;
+    HemisphereDegrees = 170.0f;
+    MeshEdgeDegrees = 3.6f;
+    Material = nullptr;
+    
+    DomeMesh = CreateDefaultSubobject<UProceduralMeshComponent>(TEXT("DomeMesh"));
+    DomeMesh->SetupAttachment(this);
+
+    //BuildDomeMesh();
+    
+    //bUseComplexAsSimpleCollision = true; // Since it is concave
+    
+    //CreateMeshSection(0, MeshVerts, MeshTris, MeshNormals, MeshUVs, MeshColors, MeshTangents, true);
+}
+
+UDomeDisplayComponent::~UDomeDisplayComponent()
+{
+    Material = nullptr;
+}
+
+#define PI_2 (2.0f * PI)
+
+void UDomeDisplayComponent::BuildDomeMesh()
+{
+    int numLatSections = 1 + int(HemisphereDegrees / MeshEdgeDegrees / 2.0f);
+    int numLonSections = 1 + int(360.0f / MeshEdgeDegrees);
+    
+    // DEBUG: Just make it simpler for debugging
+    //numLatSections = 2;
+    
+    UE_LOG(DomeViewer, Display, TEXT("BuildDomeMesh: LatSections %d, LonSections: %d"), numLatSections, numLonSections);
+
+    const FVector forward = FVector(1.0f, 0.0f, 0.0f);
+    const FVector right = FVector(0.0f, 1.0f, 0.0f);
+    const FVector up = FVector(0.0f, 0.0f, 1.0f);
+    
+    int numVerts = 1 + numLatSections * numLonSections;
+    MeshVerts.Reserve(numVerts);
+    MeshUVs.Reserve(numVerts);
+    MeshTris.Reserve(3*numVerts); // TODO: Resolve real number of triangles
+    
+    const float deltaLatRads = (PI * HemisphereDegrees / 360.0f) / float(numLatSections - 1);
+    const float deltaLonRads = PI_2 / float(numLonSections);
+    
+    // Compute the vertices, starting at top
+    MeshVerts.Add(up * Radius);
+    MeshNormals.Add(-up);
+    //MeshTangents.Add(right);
+
+    for (int latIdx = 1; latIdx < numLatSections; ++latIdx)
+    {
+        float latAngle = latIdx * deltaLatRads;
+        float latSin = sin(latAngle);
+        float latCos = cos(latAngle);
+        FVector upLoc = up * latCos;
+        
+        for (int lonIdx = 0; lonIdx < numLonSections; ++lonIdx)
+        {
+            float lonSin = sin(lonIdx * PI_2 / numLonSections);
+            float lonCos = cos(lonIdx * PI_2 / numLonSections);
+            FVector unitDir(forward * (latSin * lonCos) +
+                            right * (latSin * lonSin) + upLoc);
+            MeshVerts.Add(unitDir * Radius);
+            MeshNormals.Add(-unitDir);
+        }
+    }
+    
+    // Compute mesh UVs, starting at the center
+    const FVector2D uvCenter(0.5f, 0.5f);
+    MeshUVs.Add(uvCenter);
+    
+    for (int latIdx = 1; latIdx < numLatSections; ++latIdx)
+    {
+        float uvRadius = 0.5f * float(latIdx) / float(numLatSections - 1);
+
+        for (int lonIdx = 0; lonIdx < numLonSections; ++lonIdx)
+        {
+            float lonAngle = lonIdx * deltaLonRads;
+            MeshUVs.Add(uvCenter + uvRadius * FVector2D(sin(lonAngle), cos(lonAngle)));
+        }
+    }
+
+    // Compute the triangle indices
+    // ... first the cap
+    for (int lonIdx = 0; lonIdx < numLonSections; ++lonIdx)
+    {
+        // Counter clock-wise, triangle fan
+        MeshTris.Add(1 + lonIdx);
+        MeshTris.Add(1 + ((lonIdx + 1) % numLonSections));
+        MeshTris.Add(0);
+    }
+    // ... then the rest
+    for (int latIdx = 1; latIdx < numLatSections - 1; ++latIdx)
+    {
+        int32 topBase = 1 + (latIdx - 1) * numLonSections;
+        int32 bottomBase = 1 + latIdx * numLonSections;
+
+        for (int lonIdx = 0; lonIdx < numLonSections; ++lonIdx)
+        {
+            // Make quads, two triangles
+            // Counter clock-wise
+            MeshTris.Add(bottomBase + lonIdx);
+            MeshTris.Add(bottomBase + (lonIdx + 1) % numLonSections);
+            MeshTris.Add(topBase + lonIdx);
+
+            MeshTris.Add(bottomBase + (lonIdx + 1) % numLonSections);
+            MeshTris.Add(topBase + (lonIdx + 1) % numLonSections);
+            MeshTris.Add(topBase + lonIdx);
+        }
+    }
+}
+
+bool UDomeDisplayComponent::UpdateDomeMesh()
+{
+    BuildDomeMesh();
+
+    DomeMesh->CreateMeshSection(0, MeshVerts, MeshTris, MeshNormals, MeshUVs, MeshColors, MeshTangents, false);
+
+    if (Material != nullptr)
+    {
+        DomeMesh->SetMaterial(0, Material);
+    }
+
+    DomeMesh->SetRelativeRotation(FRotator(-TiltAngle, 0.0f, 0.0f));
+
+    return true;
+}

Source/DomeViewerVR/Public/DomeDisplayComponent.h

-// Fill out your copyright notice in the Description page of Project Settings.
+// Copyright 2019 Patric Ljung
+// Linkoping University, Media and Information Technology, Visualization Center C
+// License: BSD-3-Clause (https://opensource.org/licenses/BSD-3-Clause)
 
 #pragma once
 
 #include "CoreMinimal.h"
 #include "ProceduralMeshComponent.h"
+// TODO: Move to .cpp file and provide forward declaration here instead
+#include "Materials/MaterialInterface.h"
+
 #include "DomeDisplayComponent.generated.h"
 
 /**
  * 
  */
-UCLASS()
-class DOMEVIEWERVR_API UDomeDisplayComponent : public UProceduralMeshComponent
+UCLASS(BlueprintType, Category = "Dome",
+       Meta = (BlueprintSpawnableComponent, Tooltip = "A component that dynamically creates a UV-mapped dome hemisphere mesh"))
+class DOMEVIEWERVR_API UDomeDisplayComponent : public USceneComponent
 {
 	GENERATED_BODY()
 	
+public:
+    UDomeDisplayComponent();
+    ~UDomeDisplayComponent();
+
+    UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Dome",
+              Meta = (Tooltip = "The radius of the dome"))
+    float Radius;
+    
+    UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Dome",
+              Meta = (Tooltip = "How many degrees is the dome tilted forward"))
+    float TiltAngle;
+
+    UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Dome",
+              Meta = (Tooltip = "How many degrees the hemisphere spans, 180 degrees makes it a full hemishphere"))
+    float HemisphereDegrees;
+
+    UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Dome",
+              Meta = (Tooltip = "Mesh resolution, degrees per bottom edge"))
+    float MeshEdgeDegrees;
+
+    UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Dome",
+              Meta = (Tooltip = "Dome display mesh material"))
+    UMaterialInterface * Material;
+
+//    UPROPERTY(EditAnywhere, BlueprintRead, Category = "Dome",
+//              Meta = (Tooltip = "Dome display mesh material"))
+    UPROPERTY()
+    UProceduralMeshComponent * DomeMesh;
+
+public:
+    UFUNCTION(BlueprintCallable, Category = "Dome",
+              Meta = (Tooltip = "Update the dome mesh using current settings"))
+    bool UpdateDomeMesh();
+    
+protected:
+    // TODO: Add method to capture editor changes and call BuildDomeMesh
+
+    void BuildDomeMesh();
+
+    TArray<FVector>     MeshVerts;
+    TArray<int32>       MeshTris;
+    TArray<FVector>     MeshNormals;
+    TArray<FVector2D>   MeshUVs;
+    TArray<FColor>      MeshColors;
+    TArray<FProcMeshTangent> MeshTangents;
+
 };