虚幻编辑器相关笔记
blueprint viewport
选中组件后，有些模型会绘制一些标识，是通过 ComponentVisualizers.cpp 来实现的。
部分代码截取：
void FComponentVisualizersModule::StartupModule()
{
RegisterComponentVisualizer(UPointLightComponent::StaticClass()->GetFName(), MakeShareable(new FPointLightComponentVisualizer));
RegisterComponentVisualizer(USpotLightComponent::StaticClass()->GetFName(), MakeShareable(new FSpotLightComponentVisualizer));
RegisterComponentVisualizer(URectLightComponent::StaticClass()->GetFName(), MakeShareable(new FRectLightComponentVisualizer));
RegisterComponentVisualizer(UAudioComponent::StaticClass()->GetFName(), MakeShareable(new FAudioComponentVisualizer));
RegisterComponentVisualizer(UForceFeedbackComponent::StaticClass()->GetFName(), MakeShareable(new FForceFeedbackComponentVisualizer));
RegisterComponentVisualizer(URadialForceComponent::StaticClass()->GetFName(), MakeShareable(new FRadialForceComponentVisualizer));
RegisterComponentVisualizer(UPhysicsConstraintComponent::StaticClass()->GetFName(), MakeShareable(new FConstraintComponentVisualizer));
RegisterComponentVisualizer(UPhysicalAnimationComponent::StaticClass()->GetFName(), MakeShareable(new FPhysicsAnimationComponentVisualizer));
RegisterComponentVisualizer(USpringArmComponent::StaticClass()->GetFName(), MakeShareable(new FSpringArmComponentVisualizer));
RegisterComponentVisualizer(USplineComponent::StaticClass()->GetFName(), MakeShareable(new FSplineComponentVisualizer));
RegisterComponentVisualizer(USplineMeshComponent::StaticClass()->GetFName(), MakeShareable(new FSplineMeshComponentVisualizer));
RegisterComponentVisualizer(UPawnSensingComponent::StaticClass()->GetFName(), MakeShareable(new FSensingComponentVisualizer));
RegisterComponentVisualizer(UPhysicsSpringComponent::StaticClass()->GetFName(), MakeShareable(new FSpringComponentVisualizer));
RegisterComponentVisualizer(UDecalComponent::StaticClass()->GetFName(), MakeShareable(new FDecalComponentVisualizer));
RegisterComponentVisualizer(UStereoLayerComponent::StaticClass()->GetFName(), MakeShareable(new FStereoLayerComponentVisualizer));
RegisterComponentVisualizer(UWorldPartitionStreamingSourceComponent::StaticClass()->GetFName(), MakeShareable(new FWorldPartitionStreamingSourceComponentVisualizer));
RegisterComponentVisualizer(ULocalFogVolumeComponent::StaticClass()->GetFName(), MakeShareable(new FLocalFogVolumeComponentVisualizer));
}
其中 sprintarm 的绘制实现：FSpringArmComponentVisualizer
static const FColor ArmColor(255,0,0);
void FSpringArmComponentVisualizer::DrawVisualization(const UActorComponent* Component, const FSceneView* View, FPrimitiveDrawInterface* PDI)
{
if (const USpringArmComponent* SpringArm = Cast<const USpringArmComponent>(Component))
{
PDI->DrawLine( SpringArm->GetComponentLocation(), SpringArm->GetSocketTransform(TEXT("SpringEndpoint"),RTS_World).GetTranslation(), ArmColor, SDPG_World );
}
}