// Copyright Epic Games, Inc. All Rights Reserved.

#include "ThumbnailRendering/PhysicsAssetThumbnailRenderer.h"
#include "Misc/App.h"
#include "ShowFlags.h"
#include "SceneView.h"
#include "PhysicsEngine/PhysicsAsset.h"
#include "ThumbnailHelpers.h"

UPhysicsAssetThumbnailRenderer::UPhysicsAssetThumbnailRenderer(const FObjectInitializer& ObjectInitializer)
    : Super(ObjectInitializer)
{
    ThumbnailScene = nullptr;
}

void UPhysicsAssetThumbnailRenderer::Draw(UObject* Object, int32 X, int32 Y, uint32 Width, uint32 Height, FRenderTarget* RenderTarget, FCanvas* Canvas, bool bAdditionalViewFamily)
{
    UPhysicsAsset* PhysicsAsset = Cast<UPhysicsAsset>(Object);
    if (PhysicsAsset != nullptr)
    {
        if (ThumbnailScene == nullptr)
        {
            ThumbnailScene = new FPhysicsAssetThumbnailScene();
        }

        ThumbnailScene->SetPhysicsAsset(PhysicsAsset);
        FSceneViewFamilyContext ViewFamily(FSceneViewFamily::ConstructionValues(RenderTarget, ThumbnailScene->GetScene(), FEngineShowFlags(ESFIM_Game))
                                               .SetWorldTimes(FApp::GetCurrentTime() - GStartTime, FApp::GetDeltaTime(), FApp::GetCurrentTime() - GStartTime)
                                               .SetAdditionalViewFamily(bAdditionalViewFamily));

        ViewFamily.EngineShowFlags.DisableAdvancedFeatures();
        ViewFamily.EngineShowFlags.MotionBlur = 0;
        ViewFamily.EngineShowFlags.LOD        = 0;

        ThumbnailScene->GetView(&ViewFamily, X, Y, Width, Height);
        RenderViewFamily(Canvas, &ViewFamily);
        ThumbnailScene->SetPhysicsAsset(nullptr);
    }
}

void UPhysicsAssetThumbnailRenderer::BeginDestroy()
{
    if (ThumbnailScene != nullptr)
    {
        delete ThumbnailScene;
        ThumbnailScene = nullptr;
    }

    Super::BeginDestroy();
}