o3de/Gems/Terrain/Code/Source/Components/TerrainWorldDebuggerComponent.cpp

/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */

#include <Components/TerrainWorldDebuggerComponent.h>

#include <AzCore/Asset/AssetManager.h>
#include <AzCore/Asset/AssetManagerBus.h>
#include <AzCore/Component/Entity.h>
#include <AzCore/RTTI/BehaviorContext.h>
#include <AzCore/Serialization/EditContext.h>
#include <AzCore/Serialization/SerializeContext.h>

#include <AzFramework/Visibility/EntityBoundsUnionBus.h>

#include <Atom/RPI.Public/View.h>
#include <Atom/RPI.Public/ViewportContext.h>
#include <Atom/RPI.Public/ViewportContextBus.h>

namespace Terrain
{
    void TerrainWorldDebuggerConfig::Reflect(AZ::ReflectContext* context)
    {
        AZ::SerializeContext* serialize = azrtti_cast<AZ::SerializeContext*>(context);
        if (serialize)
        {
            serialize->Class<TerrainWorldDebuggerConfig, AZ::ComponentConfig>()
                ->Version(1)
                ->Field("DebugWireframe", &TerrainWorldDebuggerConfig::m_drawWireframe)
                ->Field("DebugWorldBounds", &TerrainWorldDebuggerConfig::m_drawWorldBounds)
            ;

            AZ::EditContext* edit = serialize->GetEditContext();
            if (edit)
            {
                edit->Class<TerrainWorldDebuggerConfig>(
                    "Terrain World Debugger Component", "Optional component for enabling terrain debugging features.")
                    ->ClassElement(AZ::Edit::ClassElements::EditorData, "")
                    ->Attribute(AZ::Edit::Attributes::AppearsInAddComponentMenu, AZStd::vector<AZ::Crc32>({ AZ_CRC_CE("Level") }))
                    ->Attribute(AZ::Edit::Attributes::Visibility, AZ::Edit::PropertyVisibility::ShowChildrenOnly)
                    ->Attribute(AZ::Edit::Attributes::AutoExpand, true)

                    ->DataElement(AZ::Edit::UIHandlers::Default, &TerrainWorldDebuggerConfig::m_drawWireframe, "Show Wireframe", "")
                    ->DataElement(AZ::Edit::UIHandlers::Default, &TerrainWorldDebuggerConfig::m_drawWorldBounds, "Show World Bounds", "");
            }
        }
    }

    void TerrainWorldDebuggerComponent::GetProvidedServices(AZ::ComponentDescriptor::DependencyArrayType& services)
    {
        services.push_back(AZ_CRC_CE("TerrainDebugService"));
    }

    void TerrainWorldDebuggerComponent::GetIncompatibleServices(AZ::ComponentDescriptor::DependencyArrayType& services)
    {
        services.push_back(AZ_CRC_CE("TerrainDebugService"));
    }

    void TerrainWorldDebuggerComponent::GetRequiredServices(AZ::ComponentDescriptor::DependencyArrayType& services)
    {
        services.push_back(AZ_CRC_CE("TerrainService"));
    }

    void TerrainWorldDebuggerComponent::Reflect(AZ::ReflectContext* context)
    {
        TerrainWorldDebuggerConfig::Reflect(context);

        AZ::SerializeContext* serialize = azrtti_cast<AZ::SerializeContext*>(context);
        if (serialize)
        {
            serialize->Class<TerrainWorldDebuggerComponent, AZ::Component>()
                ->Version(0)
                ->Field("Configuration", &TerrainWorldDebuggerComponent::m_configuration)
            ;
        }
    }

    TerrainWorldDebuggerComponent::TerrainWorldDebuggerComponent(const TerrainWorldDebuggerConfig& configuration)
        : m_configuration(configuration)
    {
    }

    TerrainWorldDebuggerComponent::~TerrainWorldDebuggerComponent()
    {
    }

    void TerrainWorldDebuggerComponent::Activate()
    {
        m_wireframeBounds = AZ::Aabb::CreateNull();

        AzFramework::EntityDebugDisplayEventBus::Handler::BusConnect(GetEntityId());
        AzFramework::BoundsRequestBus::Handler::BusConnect(GetEntityId());
        AzFramework::Terrain::TerrainDataNotificationBus::Handler::BusConnect();
    }

    void TerrainWorldDebuggerComponent::Deactivate()
    {
        AzFramework::Terrain::TerrainDataNotificationBus::Handler::BusDisconnect();
        AzFramework::BoundsRequestBus::Handler::BusDisconnect();
        AzFramework::EntityDebugDisplayEventBus::Handler::BusDisconnect();

        m_wireframeBounds = AZ::Aabb::CreateNull();
        m_wireframeSectors.clear();
    }

    bool TerrainWorldDebuggerComponent::ReadInConfig(const AZ::ComponentConfig* baseConfig)
    {
        if (auto config = azrtti_cast<const TerrainWorldDebuggerConfig*>(baseConfig))
        {
            m_configuration = *config;
            return true;
        }
        return false;
    }

    bool TerrainWorldDebuggerComponent::WriteOutConfig(AZ::ComponentConfig* outBaseConfig) const
    {
        if (auto config = azrtti_cast<TerrainWorldDebuggerConfig*>(outBaseConfig))
        {
            *config = m_configuration;
            return true;
        }
        return false;
    }

    AZ::Aabb TerrainWorldDebuggerComponent::GetWorldBounds()
    {
        AZ::Aabb terrainAabb = AZ::Aabb::CreateFromPoint(AZ::Vector3::CreateZero());
        AzFramework::Terrain::TerrainDataRequestBus::BroadcastResult(
            terrainAabb, &AzFramework::Terrain::TerrainDataRequests::GetTerrainAabb);

        return terrainAabb;
    }

    AZ::Aabb TerrainWorldDebuggerComponent::GetLocalBounds()
    {
        // This is a level component, so the local bounds will always be the same as the world bounds.
        return GetWorldBounds();
    }

    void TerrainWorldDebuggerComponent::DisplayEntityViewport(
        const AzFramework::ViewportInfo& viewportInfo, AzFramework::DebugDisplayRequests& debugDisplay)
    {
        // Draw a wireframe box around the entire terrain world bounds
        if (m_configuration.m_drawWorldBounds)
        {
            AZ::Color outlineColor(1.0f, 0.0f, 0.0f, 1.0f);
            AZ::Aabb aabb = GetWorldBounds();

            debugDisplay.SetColor(outlineColor);
            debugDisplay.DrawWireBox(aabb.GetMin(), aabb.GetMax());
        }

        // Draw a wireframe representation of the terrain surface
        if (m_configuration.m_drawWireframe && !m_wireframeSectors.empty())
        {
            // Start by assuming we'll draw the entire world.
            AZ::Aabb drawingAabb = GetWorldBounds();

            // Assuming we can get the camera, reduce the drawing bounds to a fixed distance around the camera.
            if (auto viewportContextRequests = AZ::RPI::ViewportContextRequests::Get(); viewportContextRequests)
            {
                // Get the current camera position.
                AZ::RPI::ViewportContextPtr viewportContext = viewportContextRequests->GetViewportContextById(viewportInfo.m_viewportId);
                AZ::Vector3 cameraPos = viewportContext->GetCameraTransform().GetTranslation();

                // Determine how far to draw in each direction in world space based on our MaxSectorsToDraw
                AZ::Vector2 queryResolution = AZ::Vector2(1.0f);
                AzFramework::Terrain::TerrainDataRequestBus::BroadcastResult(
                    queryResolution, &AzFramework::Terrain::TerrainDataRequests::GetTerrainHeightQueryResolution);
                AZ::Vector3 viewDistance(
                    queryResolution.GetX() * SectorSizeInGridPoints * sqrtf(MaxSectorsToDraw),
                    queryResolution.GetY() * SectorSizeInGridPoints * sqrtf(MaxSectorsToDraw),
                    0.0f);

                // Create an AABB around the camera based on how far we want to be able to draw in each direction and clamp the
                // drawing AABB to it.
                AZ::Aabb cameraAabb = AZ::Aabb::CreateFromMinMax(
                    AZ::Vector3(
                        cameraPos.GetX() - viewDistance.GetX(), cameraPos.GetY() - viewDistance.GetY(), drawingAabb.GetMin().GetZ()),
                    AZ::Vector3(
                        cameraPos.GetX() + viewDistance.GetX(), cameraPos.GetY() + viewDistance.GetY(), drawingAabb.GetMin().GetZ()));
                drawingAabb.Clamp(cameraAabb);
            }

            // For each sector, if it appears within our view distance, draw it.
            for (auto& sector : m_wireframeSectors)
            {
                if (drawingAabb.Overlaps(sector.m_aabb))
                {
                    if (!sector.m_lineVertices.empty())
                    {
                        const AZ::Color primaryColor = AZ::Color(0.25f, 0.25f, 0.25f, 1.0f);
                        debugDisplay.DrawLines(sector.m_lineVertices, primaryColor);
                    }
                    else
                    {
                        AZ_Warning("Debug", false, "empty sector!");
                    }
                }
            }
        }
    }

    void TerrainWorldDebuggerComponent::RefreshCachedWireframeGrid(const AZ::Aabb& dirtyRegion)
    {
        // Get the terrain world bounds and grid resolution.

        AZ::Aabb worldBounds = GetWorldBounds();

        AZ::Vector2 queryResolution = AZ::Vector2(1.0f);
        AzFramework::Terrain::TerrainDataRequestBus::BroadcastResult(
            queryResolution, &AzFramework::Terrain::TerrainDataRequests::GetTerrainHeightQueryResolution);

        // Calculate the world size of each sector.  Note that this size actually ends at the last point, not the last square.
        // So for example, the sector size for 3 points will go from (*--*--*) even though it will be used to draw (*--*--*--).
        const float xSectorSize = (queryResolution.GetX() * SectorSizeInGridPoints);
        const float ySectorSize = (queryResolution.GetY() * SectorSizeInGridPoints);

        // Calculate the total number of sectors to cache.  The world bounds might not be evenly divisible by sector bounds, so we add
        // an extra sector's worth of size in each direction so that clamping down to an integer still accounts for that fractional sector.
        const int32_t numSectorsX = aznumeric_cast<int32_t>((worldBounds.GetXExtent() + xSectorSize) / xSectorSize);
        const int32_t numSectorsY = aznumeric_cast<int32_t>((worldBounds.GetYExtent() + ySectorSize) / ySectorSize);

        // If we haven't cached anything before, or if the world bounds has changed, clear our cache structure and repopulate it
        // with WireframeSector entries with the proper AABB sizes.
        if (!m_wireframeBounds.IsValid() || !dirtyRegion.IsValid() || !m_wireframeBounds.IsClose(worldBounds))
        {
            m_wireframeBounds = worldBounds;

            m_wireframeSectors.clear();
            m_wireframeSectors.reserve(numSectorsX * numSectorsY);

            for (int32_t ySector = 0; ySector < numSectorsY; ySector++)
            {
                for (int32_t xSector = 0; xSector < numSectorsX; xSector++)
                {
                    // For each sector, set up the AABB for the sector and reserve memory for the line vertices.
                    WireframeSector sector;
                    sector.m_lineVertices.reserve(VerticesPerSector);
                    sector.m_aabb = AZ::Aabb::CreateFromMinMax(
                        AZ::Vector3(
                            worldBounds.GetMin().GetX() + (xSector * xSectorSize), worldBounds.GetMin().GetY() + (ySector * ySectorSize),
                            worldBounds.GetMin().GetZ()),
                        AZ::Vector3(
                            worldBounds.GetMin().GetX() + ((xSector + 1) * xSectorSize),
                            worldBounds.GetMin().GetY() + ((ySector + 1) * ySectorSize), worldBounds.GetMax().GetZ()));

                    sector.m_aabb.Clamp(worldBounds);

                    m_wireframeSectors.push_back(AZStd::move(sector));
                }
            }

            // Notify the visibility system that our bounds have changed.
            AzFramework::IEntityBoundsUnionRequestBus::Broadcast(
                &AzFramework::IEntityBoundsUnionRequestBus::Events::RefreshEntityLocalBoundsUnion, GetEntityId());
        }

        // For each sector, if it overlaps with the dirty region, clear it out and recache the wireframe line data.
        for (auto& sector : m_wireframeSectors)
        {
            if (dirtyRegion.IsValid() && !dirtyRegion.Overlaps(sector.m_aabb))
            {
                continue;
            }

            sector.m_lineVertices.clear();

            for (float y = sector.m_aabb.GetMin().GetY(); y < sector.m_aabb.GetMax().GetY(); y += queryResolution.GetY())
            {
                for (float x = sector.m_aabb.GetMin().GetX(); x < sector.m_aabb.GetMax().GetX(); x += queryResolution.GetX())
                {
                    float x1 = x + queryResolution.GetX();
                    float y1 = y + queryResolution.GetY();

                    float z00 = 0.0f;
                    float z01 = 0.0f;
                    float z10 = 0.0f;
                    bool terrainExists;

                    AzFramework::Terrain::TerrainDataRequestBus::BroadcastResult(
                        z00, &AzFramework::Terrain::TerrainDataRequests::GetHeightFromFloats, x, y,
                        AzFramework::Terrain::TerrainDataRequests::Sampler::EXACT, &terrainExists);
                    AzFramework::Terrain::TerrainDataRequestBus::BroadcastResult(
                        z01, &AzFramework::Terrain::TerrainDataRequests::GetHeightFromFloats, x, y1,
                        AzFramework::Terrain::TerrainDataRequests::Sampler::EXACT, &terrainExists);
                    AzFramework::Terrain::TerrainDataRequestBus::BroadcastResult(
                        z10, &AzFramework::Terrain::TerrainDataRequests::GetHeightFromFloats, x1, y,
                        AzFramework::Terrain::TerrainDataRequests::Sampler::EXACT, &terrainExists);

                    sector.m_lineVertices.push_back(AZ::Vector3(x, y, z00));
                    sector.m_lineVertices.push_back(AZ::Vector3(x1, y, z10));

                    sector.m_lineVertices.push_back(AZ::Vector3(x, y, z00));
                    sector.m_lineVertices.push_back(AZ::Vector3(x, y1, z01));
                }
            }
        }
    }

    void TerrainWorldDebuggerComponent::OnTerrainDataChanged(const AZ::Aabb& dirtyRegion, TerrainDataChangedMask dataChangedMask)
    {
        if (dataChangedMask & (TerrainDataChangedMask::Settings | TerrainDataChangedMask::HeightData))
        {
            RefreshCachedWireframeGrid(dirtyRegion);
        }
    }


} // namespace Terrain