DynamicGeometry.cpp

//
// Copyright (c) 2008-2015 the Urho3D project.
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// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
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// furnished to do so, subject to the following conditions:
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// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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#include <Urho3D/Urho3D.h>

#include <Urho3D/Graphics/Camera.h>
#include <Urho3D/Core/CoreEvents.h>
#include <Urho3D/Engine/Engine.h>
#include <Urho3D/UI/Font.h>
#include <Urho3D/Graphics/Geometry.h>
#include <Urho3D/Graphics/Graphics.h>
#include <Urho3D/Graphics/IndexBuffer.h>
#include <Urho3D/Input/Input.h>
#include <Urho3D/Graphics/Light.h>
#include <Urho3D/IO/Log.h>
#include <Urho3D/Graphics/Model.h>
#include <Urho3D/Graphics/Octree.h>
#include <Urho3D/Core/Profiler.h>
#include <Urho3D/Graphics/Renderer.h>
#include <Urho3D/Resource/ResourceCache.h>
#include <Urho3D/Scene/Scene.h>
#include <Urho3D/Graphics/StaticModel.h>
#include <Urho3D/UI/Text.h>
#include <Urho3D/Graphics/VertexBuffer.h>
#include <Urho3D/UI/UI.h>
#include <Urho3D/Graphics/Zone.h>

#include "DynamicGeometry.h"

#include <Urho3D/DebugNew.h>

DEFINE_APPLICATION_MAIN(DynamicGeometry)

DynamicGeometry::DynamicGeometry(Context* context) :
    Sample(context),
    animate_(true),
    time_(0.0f)
{
}

void DynamicGeometry::Start()
{
    // Execute base class startup
    Sample::Start();

    // Create the scene content
    CreateScene();

    // Create the UI content
    CreateInstructions();

    // Setup the viewport for displaying the scene
    SetupViewport();

    // Hook up to the frame update events
    SubscribeToEvents();
}

void DynamicGeometry::CreateScene()
{
    ResourceCache* cache = GetSubsystem<ResourceCache>();

    scene_ = new Scene(context_);

    // Create the Octree component to the scene so that drawable objects can be rendered. Use default volume
    // (-1000, -1000, -1000) to (1000, 1000, 1000)
    scene_->CreateComponent<Octree>();

    // Create a Zone for ambient light & fog control
    Node* zoneNode = scene_->CreateChild("Zone");
    Zone* zone = zoneNode->CreateComponent<Zone>();
    zone->SetBoundingBox(BoundingBox(-1000.0f, 1000.0f));
    zone->SetFogColor(Color(0.2f, 0.2f, 0.2f));
    zone->SetFogStart(200.0f);
    zone->SetFogEnd(300.0f);

    // Create a directional light
    Node* lightNode = scene_->CreateChild("DirectionalLight");
    lightNode->SetDirection(Vector3(-0.6f, -1.0f, -0.8f)); // The direction vector does not need to be normalized
    Light* light = lightNode->CreateComponent<Light>();
    light->SetLightType(LIGHT_DIRECTIONAL);
    light->SetColor(Color(0.4f, 1.0f, 0.4f));
    light->SetSpecularIntensity(1.5f);

    // Get the original model and its unmodified vertices, which are used as source data for the animation
    Model* originalModel = cache->GetResource<Model>("Models/Box.mdl");
    if (!originalModel)
    {
        LOGERROR("Model not found, cannot initialize example scene");
        return;
    }
    // Get the vertex buffer from the first geometry's first LOD level
    VertexBuffer* buffer = originalModel->GetGeometry(0, 0)->GetVertexBuffer(0);
    const unsigned char* vertexData = (const unsigned char*)buffer->Lock(0, buffer->GetVertexCount());
    if (vertexData)
    {
        unsigned numVertices = buffer->GetVertexCount();
        unsigned vertexSize = buffer->GetVertexSize();
        // Copy the original vertex positions
        for (unsigned i = 0; i < numVertices; ++i)
        {
            const Vector3& src = *reinterpret_cast<const Vector3*>(vertexData + i * vertexSize);
            originalVertices_.Push(src);
        }
        buffer->Unlock();

        // Detect duplicate vertices to allow seamless animation
        vertexDuplicates_.Resize(originalVertices_.Size());
        for (unsigned i = 0; i < originalVertices_.Size(); ++i)
        {
            vertexDuplicates_[i] = i; // Assume not a duplicate
            for (unsigned j = 0; j < i; ++j)
            {
                if (originalVertices_[i].Equals(originalVertices_[j]))
                {
                    vertexDuplicates_[i] = j;
                    break;
                }
            }
        }
    }
    else
    {
        LOGERROR("Failed to lock the model vertex buffer to get original vertices");
        return;
    }

    // Create StaticModels in the scene. Clone the model for each so that we can modify the vertex data individually
    for (int y = -1; y <= 1; ++y)
    {
        for (int x = -1; x <= 1; ++x)
        {
            Node* node = scene_->CreateChild("Object");
            node->SetPosition(Vector3(x * 2.0f, 0.0f, y * 2.0f));
            StaticModel* object = node->CreateComponent<StaticModel>();
            SharedPtr<Model> cloneModel = originalModel->Clone();
            object->SetModel(cloneModel);
            // Store the cloned vertex buffer that we will modify when animating
            animatingBuffers_.Push(SharedPtr<VertexBuffer>(cloneModel->GetGeometry(0, 0)->GetVertexBuffer(0)));
        }
    }

    // Finally create one model (pyramid shape) and a StaticModel to display it from scratch
    // Note: there are duplicated vertices to enable face normals. We will calculate normals programmatically
    {
        const unsigned numVertices = 18;

        float vertexData[] = {
            // Position
            0.0f, 0.5f, 0.0f,
            0.5f, -0.5f, 0.5f,
            0.5f, -0.5f, -0.5f,

            0.0f, 0.5f, 0.0f,
            -0.5f, -0.5f, 0.5f,
            0.5f, -0.5f, 0.5f,

            0.0f, 0.5f, 0.0f,
            -0.5f, -0.5f, -0.5f,
            -0.5f, -0.5f, 0.5f,

            0.0f, 0.5f, 0.0f,
            0.5f, -0.5f, -0.5f,
            -0.5f, -0.5f, -0.5f,

            0.5f, -0.5f, -0.5f,
            0.5f, -0.5f, 0.5f,
            -0.5f, -0.5f, 0.5f,

            0.5f, -0.5f, -0.5f,
            -0.5f, -0.5f, 0.5f,
            -0.5f, -0.5f, -0.5f,
        };

        float normalData[] = {
            // Normal
             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,

             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,

             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,

             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,

             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,

             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f,
             0.0f, 0.0f, 0.0f
        };

        const unsigned short indexData[] = {
            0, 1, 2,
            3, 4, 5,
            6, 7, 8,
            9, 10, 11,
            12, 13, 14,
            15, 16, 17
        };

        // Calculate face normals now
        for (unsigned i = 0; i < numVertices; i += 3)
        {
            Vector3& v1 = *(reinterpret_cast<Vector3*>(&vertexData[3 * i]));
            Vector3& v2 = *(reinterpret_cast<Vector3*>(&vertexData[3 * (i + 1)]));
            Vector3& v3 = *(reinterpret_cast<Vector3*>(&vertexData[3 * (i + 2)]));
            Vector3& n1 = *(reinterpret_cast<Vector3*>(&normalData[3 * i]));
            Vector3& n2 = *(reinterpret_cast<Vector3*>(&normalData[3 * (i + 1)]));
            Vector3& n3 = *(reinterpret_cast<Vector3*>(&normalData[3 * (i + 2)]));

            Vector3 edge1 = v1 - v2;
            Vector3 edge2 = v1 - v3;
            n1 = n2 = n3 = edge1.CrossProduct(edge2).Normalized();
        }

        SharedPtr<Model> fromScratchModel(new Model(context_));
        SharedPtr<VertexBuffer> vb(new VertexBuffer(context_));
        SharedPtr<VertexBuffer> nb(new VertexBuffer(context_));
        SharedPtr<IndexBuffer> ib(new IndexBuffer(context_));
        SharedPtr<Geometry> geom(new Geometry(context_));

        // Shadowed buffer needed for raycasts to work, and so that data can be automatically restored on device loss
        vb->SetShadowed(true);
        vb->SetSize(numVertices, MASK_POSITION);
        vb->SetData(vertexData);

        nb->SetShadowed(true);
        nb->SetSize(numVertices, MASK_NORMAL);
        nb->SetData(normalData);

        ib->SetShadowed(true);
        ib->SetSize(numVertices, false);
        ib->SetData(indexData);

        geom->SetVertexBuffer(0, vb);
        geom->SetVertexBuffer(1, nb);
        geom->SetIndexBuffer(ib);
        geom->SetDrawRange(TRIANGLE_LIST, 0, numVertices);

        fromScratchModel->SetNumGeometries(1);
        fromScratchModel->SetGeometry(0, 0, geom);
        fromScratchModel->SetBoundingBox(BoundingBox(Vector3(-0.5f, -0.5f, -0.5f), Vector3(0.5f, 0.5f, 0.5f)));

        Node* node = scene_->CreateChild("FromScratchObject");
        node->SetPosition(Vector3(0.0f, 3.0f, 0.0f));
        StaticModel* object = node->CreateComponent<StaticModel>();
        object->SetModel(fromScratchModel);
    }

    // Create the camera
    cameraNode_ = new Node(context_);
    cameraNode_->SetPosition(Vector3(0.0f, 2.0f, -20.0f));
    Camera* camera = cameraNode_->CreateComponent<Camera>();
    camera->SetFarClip(300.0f);
}

void DynamicGeometry::CreateInstructions()
{
    ResourceCache* cache = GetSubsystem<ResourceCache>();
    UI* ui = GetSubsystem<UI>();

    // Construct new Text object, set string to display and font to use
    Text* instructionText = ui->GetRoot()->CreateChild<Text>();
    instructionText->SetText(
        "Use WASD keys and mouse/touch to move\n"
        "Space to toggle animation"
    );
    instructionText->SetFont(cache->GetResource<Font>("Fonts/Anonymous Pro.ttf"), 15);
    // The text has multiple rows. Center them in relation to each other
    instructionText->SetTextAlignment(HA_CENTER);

    // Position the text relative to the screen center
    instructionText->SetHorizontalAlignment(HA_CENTER);
    instructionText->SetVerticalAlignment(VA_CENTER);
    instructionText->SetPosition(0, ui->GetRoot()->GetHeight() / 4);
}

void DynamicGeometry::SetupViewport()
{
    Renderer* renderer = GetSubsystem<Renderer>();

    // Set up a viewport to the Renderer subsystem so that the 3D scene can be seen
    SharedPtr<Viewport> viewport(new Viewport(context_, scene_, cameraNode_->GetComponent<Camera>()));
    renderer->SetViewport(0, viewport);
}

void DynamicGeometry::SubscribeToEvents()
{
    // Subscribe HandleUpdate() function for processing update events
    SubscribeToEvent(E_UPDATE, HANDLER(DynamicGeometry, HandleUpdate));
}

void DynamicGeometry::MoveCamera(float timeStep)
{
    // Do not move if the UI has a focused element (the console)
    if (GetSubsystem<UI>()->GetFocusElement())
        return;

    Input* input = GetSubsystem<Input>();

    // Movement speed as world units per second
    const float MOVE_SPEED = 20.0f;
    // Mouse sensitivity as degrees per pixel
    const float MOUSE_SENSITIVITY = 0.1f;

    // Use this frame's mouse motion to adjust camera node yaw and pitch. Clamp the pitch between -90 and 90 degrees
    IntVector2 mouseMove = input->GetMouseMove();
    yaw_ += MOUSE_SENSITIVITY * mouseMove.x_;
    pitch_ += MOUSE_SENSITIVITY * mouseMove.y_;
    pitch_ = Clamp(pitch_, -90.0f, 90.0f);

    // Construct new orientation for the camera scene node from yaw and pitch. Roll is fixed to zero
    cameraNode_->SetRotation(Quaternion(pitch_, yaw_, 0.0f));

    // Read WASD keys and move the camera scene node to the corresponding direction if they are pressed
    if (input->GetKeyDown('W'))
        cameraNode_->Translate(Vector3::FORWARD * MOVE_SPEED * timeStep);
    if (input->GetKeyDown('S'))
        cameraNode_->Translate(Vector3::BACK * MOVE_SPEED * timeStep);
    if (input->GetKeyDown('A'))
        cameraNode_->Translate(Vector3::LEFT * MOVE_SPEED * timeStep);
    if (input->GetKeyDown('D'))
        cameraNode_->Translate(Vector3::RIGHT * MOVE_SPEED * timeStep);
}

void DynamicGeometry::AnimateObjects(float timeStep)
{
    PROFILE(AnimateObjects);

    time_ += timeStep * 100.0f;

    // Repeat for each of the cloned vertex buffers
    for (unsigned i = 0; i < animatingBuffers_.Size(); ++i)
    {
        float startPhase = time_ + i * 30.0f;
        VertexBuffer* buffer = animatingBuffers_[i];

        // Lock the vertex buffer for update and rewrite positions with sine wave modulated ones
        // Cannot use discard lock as there is other data (normals, UVs) that we are not overwriting
        unsigned char* vertexData = (unsigned char*)buffer->Lock(0, buffer->GetVertexCount());
        if (vertexData)
        {
            unsigned vertexSize = buffer->GetVertexSize();
            unsigned numVertices = buffer->GetVertexCount();
            for (unsigned j = 0; j < numVertices; ++j)
            {
                // If there are duplicate vertices, animate them in phase of the original
                float phase = startPhase + vertexDuplicates_[j] * 10.0f;
                Vector3& src = originalVertices_[j];
                Vector3& dest = *reinterpret_cast<Vector3*>(vertexData + j * vertexSize);
                dest.x_ = src.x_ * (1.0f + 0.1f * Sin(phase));
                dest.y_ = src.y_ * (1.0f + 0.1f * Sin(phase + 60.0f));
                dest.z_ = src.z_ * (1.0f + 0.1f * Sin(phase + 120.0f));
            }

            buffer->Unlock();
        }
    }
}

void DynamicGeometry::HandleUpdate(StringHash eventType, VariantMap& eventData)
{
    using namespace Update;

    // Take the frame time step, which is stored as a float
    float timeStep = eventData[P_TIMESTEP].GetFloat();

    // Toggle animation with space
    Input* input = GetSubsystem<Input>();
    if (input->GetKeyPress(KEY_SPACE))
        animate_ = !animate_;

    // Move the camera, scale movement with time step
    MoveCamera(timeStep);

    // Animate objects' vertex data if enabled
    if (animate_)
        AnimateObjects(timeStep);
}