15. Implementing Game Logic and Using Properties

#ifndef __APP_WORLD_LOGIC_H__
#define __APP_WORLD_LOGIC_H__

#include <UnigineLogic.h>
#include <UnigineStreams.h>
#include <UnigineObjects.h>
#include <UnigineEditor.h>
#include <UnigineGame.h>
#include <UnigineLights.h>
#include <UnigineMaterials.h>
#include <UnigineApp.h>
#include <UnigineConsole.h>

// auxiliary constants
const float DELTA_ANGLE = 60.0f;		// delta angle of objects rotation
const float MOVING_SPEED = 3.0f;		// speed of objects movement
const float CHANGE_INTERVAL = 1.0f;		// the interval between changes of objects' parameters, in seconds
const float SUN_ROTATION_RATE = 10.0f;	// rotation rate of the sun

class AppWorldLogic : public Unigine::WorldLogic {
	
public:
	AppWorldLogic();
	virtual ~AppWorldLogic();
	
	virtual int init();
	
	virtual int update();
	virtual int render();
	virtual int flush();
	
	virtual int shutdown();
	virtual int destroy();
	
	virtual int save(const Unigine::StreamPtr &stream);
	virtual int restore(const Unigine::StreamPtr &stream);
private:
	Unigine::Editor *editor;
	Unigine::App *app;
	Unigine::Materials *materials;
	Unigine::Properties *properties;
	Unigine::PlayerSpectatorPtr player;


	// pointers to light sources
	Unigine::LightWorldPtr thesun;
	Unigine::LightOmniPtr light_omni;
	Unigine::LightProjPtr projector;

	// auxiliary functions
	int addMeshToScene(const char *file_name, const char *mesh_name, const char *material_name, Unigine::Math::Vec3 position);
	int removeMeshFromScene(const char *node_name);
	int transformNode(Unigine::NodePtr node, float ifps);

	// initialization functions
	int initObjects();
	int initPlayer();
	int initLights();
	int initMaterials();
	int initProperties();

	// update functions
	int updateLights();
	int updateObjects();

	// shutdown functions
	int clearMaterials();
	int removeObjects();

	// scene objects vector
	Unigine::Vector <Unigine::ObjectMeshDynamicPtr> Objects;
	
	Unigine::ObjectPtr old_selection;												// pointer to previously selected object
	Unigine::Math::vec3 current_objects_scale = Unigine::Math::vec3(1.0f);			// current scaling vector for objects
	Unigine::Math::Vec3 forward_direction = Unigine::Math::Vec3(0.0f, -1.0f, 0.0f);	// current forward direction vector for objects
	float elapsed_time = CHANGE_INTERVAL;											// current time left to change current scale and forward direction of our objects
	float sun_angle = 0.0f;															// current sun position
};

#endif // __APP_WORLD_LOGIC_H__

#include "AppWorldLogic.h"
// World logic, it takes effect only when the world is loaded.
// These methods are called right after corresponding world script's (UnigineScript) methods.
using namespace Unigine;
// auxiliary variable to store the time of rendering the last frame
float ifps;

//-----------------------------------------------------------------------------------------------------------------------------
//---------------------------------------------- AUXILIARY FUNCTIONS AND METHODS ----------------------------------------------
//-----------------------------------------------------------------------------------------------------------------------------

/// method adding a Dynamic Mesh Object to the scene. If an empty filename is passed the method creates a default box; otherwise, loads a mesh-file with a given name.
int AppWorldLogic::addMeshToScene(const char *file_name, const char *mesh_name, const char *material_name, Math::Vec3 position)
{
	MeshPtr mesh = Mesh::create();
	ObjectMeshDynamicPtr omd;
	String new_property_name = String::format("%s_property", mesh_name);

	if (file_name){				// loading a mesh from a specified file
		if (!mesh->load(file_name))
		{
			Log::error("\nError opening .mesh file!\n");
			mesh.clear();
			
			return 0;
		}
		else omd = ObjectMeshDynamic::create(mesh);
	}
	else																// creating a default box
	{
		mesh->addBoxSurface("box_surface", Math::vec3(0.5f));

		omd = ObjectMeshDynamic::create(mesh);
	}

	// setting node material, name and position
	omd->setMaterial(material_name, "*");
	omd->setName(mesh_name);
	omd->setWorldPosition(position);

	//inheriting a new property from "surface_base_1"
	properties->findManualProperty("surface_base_1")->inherit(new_property_name.get());

	// assigning the new property to the node and setting values of its parameters
	omd->setProperty(0,new_property_name.get());
	omd->getProperty(0)->setParameterString(omd->getProperty(0)->findParameter("material"), material_name);
	omd->getProperty(0)->setParameterInt(omd->getProperty(0)->findParameter("selected"), 0);

	// enabling intersection detection for the first surface (0)
	omd->setIntersection(1, 0);
	
	// passing node ownership to the editor as a runtime node
	omd->release();
	editor->addNode(omd->getNode());

	// updating the list of scene objects
	Objects.append(omd);

	// reporting progress to the console
	Log::message("-> Object %s added to the scene.\n", mesh_name);

	// clearing the mesh
	mesh->clear();

	return 1;

}
//-----------------------------------------------------------------------------------------------------------------------------
/// method deleting a Dynamic Mesh Object with a given name from the scene
int AppWorldLogic::removeMeshFromScene(const char *node_name)
{
	// getting a pointer to the node with a given name and downcasting it to ObjectMeshDynamicPtr
	ObjectMeshDynamicPtr object = ObjectMeshDynamic::cast(editor->getNodeByName(node_name));

	if (object)
	{
		if (old_selection)
		{
			// checking if the node to be removed was previously selected
			if (object->getNode() == old_selection->getNode())
			{
				// resetting old_selection pointer to NULL
				old_selection.clear();
			}
		}

		// reporting node deletion to the console
		Log::message("Removing %s node named %s from the scene.\n", object->getTypeName(), node_name);

		// removing the node with a given name from the list of scene objects
		for (int i = 0; i < Objects.size(); i++)
		{
			if (strcmp(Objects[i]->getName(), node_name) == 0) {
				Objects.remove(i);
				break;
			}
		}

		// removing the node from the scene using upcasting
		editor->removeNode(object->getNode());

		return 1;
	}

	return 0;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// method performing node transformations 
int AppWorldLogic::transformNode(NodePtr node, float ifps)
{
	// getting current node transformation matrix
	Math::Mat4 transform = node->getTransform();

	// calculating delta rotation around an arbitrary axis
	Math::quat delta_rotation = Math::quat(rand() % 2, rand() % 2, rand() % 2, DELTA_ANGLE * ifps);

	// setting node's scale, rotation and position
	node->setWorldScale(current_objects_scale);
	node->setWorldRotation(node->getWorldRotation() * delta_rotation);
	node->setWorldPosition(node->getWorldPosition() + forward_direction * MOVING_SPEED *ifps);

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// function getting an object under the mouse cursor
ObjectPtr getObjectUnderMouseCursor(const PlayerPtr &player, int mouse_x, int mouse_y, float max_dist)
{
	// setting start point (p0) at the center of player's screen
	Math::Vec3 p0 = player->getWorldPosition();

	// setting end point (p1) according to the position of the mouse cursor
	Math::Vec3 p1 = p0 + Math::Vec3(player->getDirectionFromScreen(mouse_x, mouse_y)) * max_dist;

	WorldIntersectionPtr intersection = WorldIntersection::create();

	// returning the pointer to the first intersected object if any or NULL
	return World::get()->getIntersection(p0, p1, 1, intersection);
}
//-----------------------------------------------------------------------------------------------------------------------------
/// function setting new object as selected and updating previous selection
int selectObject(ObjectPtr new_selected_object, ObjectPtr &old_selected_object)
{
	// checking if new selected object is not NULL and it has a property with parameter "selected" assigned
	if (new_selected_object)
	{
		if (new_selected_object->getProperty(0)->findParameter("selected") != -1)
		{
			// checking if we already have a previously selected object and setting its "selected" parameter of the property to 0
			if (old_selected_object)
			{
				old_selected_object->getProperty(0)->setParameterInt(old_selected_object->getProperty(0)->findParameter("selected"), 0);
			}

			// setting the "selected" parameter of the property to 1 for the new selected object 
			new_selected_object->getProperty(0)->setParameterInt(new_selected_object->getProperty(0)->findParameter("selected"), 1);

			// remembering the object as selected
			old_selected_object = new_selected_object;

			return 1;
		}
	}

	return 0;
}

//-----------------------------------------------------------------------------------------------------------------------------
//---------------------------------------------- INITIALIZATION METHODS -------------------------------------------------------
//-----------------------------------------------------------------------------------------------------------------------------
/// method performing initialization of the set of 4 boxes
int AppWorldLogic::initObjects()
{
	int index = 0;

	for (int x = 0; x < 2; x++)
	{
		for (int y = 0; y < 2; y++)
		{
			addMeshToScene(NULL, String::format("my_meshdynamic_%d", index).get(), String::format("my_mesh_base%d", index).get(), Math::Vec3(x, y, 1.0f));
			index++;
		}
	}

	// reporting progress to the console
	Log::warning("Objects generation OK!\n\n");

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// method performing initialization of the player
int AppWorldLogic::initPlayer()
{
	// creating a new PlayerSpectator instance
	player = PlayerSpectator::create();

	// setting player's FOV, ZNear, ZFar
	player->setFov(90.0f);
	player->setZNear(0.1f);
	player->setZFar(10000.0f);

	// setting player's view direction vector and position
	player->setPosition(Math::Vec3(3.0f));
	player->setDirection(Math::vec3(-1.0f), Math::vec3(0.0f, 0.0f, -1.0f));

	// setting the player to the Game singleton instance
	Game::get()->setPlayer(player->getPlayer());
	player->release();

	//reporting progress to the console
	Log::warning("\nPlayer initialization OK!\n\n");

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// method performing initialization of lights
int AppWorldLogic::initLights()
{
	// creating an omni light and setting up its parameters
	light_omni = LightOmni::create(Math::vec4(1.0f, 1.0f, 1.0f, 1.0f), 10.0f, "");
	light_omni->setWorldPosition(Math::Vec3(0.0f, 0.0f, 5.0f));
	light_omni->setIntensity(0.1f);

	// passing node ownership to the editor
	light_omni->release();
	editor->addNode(light_omni->getNode());

	// reporting progress to the console
	Log::message("-> Created a %s light source.\n", light_omni->getName());

	// creating a world light and setting up its parameters
	thesun = LightWorld::create(Math::vec4(1.0f, 1.0f, 1.0f, 1.0f));
	thesun->setName("Sun");
	thesun->setDisableAngle(90.0f);
	thesun->setIntensity(1.0f);
	thesun->setScattering(LightWorld::SCATTERING_SUN);
	thesun->setWorldRotation(Math::quat(0.0f, 1.0f, 0.0f, 170.0f));

	// passing node ownership to the editor
	thesun->release();
	editor->addNode(thesun->getNode());

	// reporting progress to the console
	Log::message("-> Created a %s light source.\n", thesun->getName());

	// creating a proj light and setting up its parameters
	projector = LightProj::create(Math::vec4(1.0f, 1.0f, 0.5f, 1.0f), 10.0f, 60.0f, "");
	projector->setWorldPosition(Math::Vec3(2.5f, 2.5f, 3.0f));
	projector->setName("projector");
	projector->setRotation(Math::quat(-45.0f, 45.0f, 0.0f));
	projector->setPenumbra(0.425f);
	projector->setIntensity(1.0f);

	// passing node ownership to the editor
	projector->release();
	editor->addNode(projector->getNode());

	// reporting progress to the console
	Log::message("-> Created a %s light source.\n", projector->getName());
	Log::warning("Lights initialization OK!\n");

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// method performing initialization of materials
int AppWorldLogic::initMaterials()
{
	// getting a pointer to materials interface
	materials = Materials::get();

	// creating a new child material of the mesh_base and setting its color
	MaterialPtr mesh_base = materials->findMaterial("mesh_base");
	MaterialPtr my_mesh_base = mesh_base->inherit("my_mesh_base0");
	my_mesh_base->setParameter(Material::PARAMETER_COLOR, Math::vec4(255, 0, 0, 255));

	// reporting progress to the console
	Log::message("\n-> Generated %s material.\n", my_mesh_base->getName());

	// creating a new child material of the mesh_base and setting its color
	my_mesh_base = mesh_base->inherit("my_mesh_base1");
	my_mesh_base->setParameter(Material::PARAMETER_COLOR, Math::vec4(0, 255, 0, 255));

	// reporting progress to the console
	Log::message("-> Generated %s material.\n", my_mesh_base->getName());

	//creating a new child material of the mesh_base and setting its color
	my_mesh_base = mesh_base->inherit("my_mesh_base2");
	my_mesh_base->setParameter(Material::PARAMETER_COLOR, Math::vec4(0, 0, 255, 255));

	// reporting progress to the console
	Log::message("-> Generated %s material.\n", my_mesh_base->getName());

	//creating a new child material of the mesh_base and setting its color
	my_mesh_base = mesh_base->inherit("my_mesh_base3");
	my_mesh_base->setParameter(Material::PARAMETER_COLOR, Math::vec4(255, 255, 0, 255));

	// reporting progress to the console
	Log::message("-> Generated %s material.\n", my_mesh_base->getName());
	Log::warning("Material generation OK!\n\n");

	// clearing material pointer
	my_mesh_base.clear();

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// method performing initialization of properties
int AppWorldLogic::initProperties()
{
	// getting a pointer to the property manager
	properties = Properties::get();

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
//---------------------------------------------------- UPDATE METHODS ---------------------------------------------------------
//-----------------------------------------------------------------------------------------------------------------------------
/// method updating the position of the sun
int AppWorldLogic::updateLights()
{
	// updating the Sun rotation angle
	sun_angle += SUN_ROTATION_RATE * ifps;
	if (sun_angle > 360.0f) sun_angle = 0.0f;

	// changing the Sun position using the new angle
	LightWorld::cast(editor->getNodeByName("Sun"))->setWorldRotation(Math::quat(Math::vec3(0.0f, 1.0f, 0.0f), 180.0f - sun_angle));

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// method updating the initial set of scene objects
int AppWorldLogic::updateObjects()
{
	ObjectMeshDynamicPtr object;

	// changing transformation for all scene objects named "my_meshdynamic_*" (initial set)
	for (auto it = Objects.begin(); it != Objects.end(); it++)
	{
		object = it.get();

		// getting the property assigned to the first surface of the object 
		PropertyPtr p = object->getProperty(0);

		// checking if such property exists and has a "selected" parameter
		if (p)
		{
			int param = p->findParameter("selected");
			if (param != -1)
				if (p->getParameterInt(param) == 1)
				{
					// if "selected" parameter value is 1 assigning "mesh_base" material to the object to highlight it
					object->setMaterial("mesh_base", "*");
				}
				else
				{
					// if "selected" parameter value is 0 assigning the material that is stored in the "material" parameter of its property
					object->setMaterial(p->getParameterString(p->findParameter("material")), "*");
				}
		}

		// if a node is named "my_meshdynamic_*" (it belongs to the initial set) change its transformation
		if (strstr(object->getName(), "my_meshdynamic_"))
		{
			// transform the node
			transformNode(object->getNode(), ifps);
		}
	}

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
//---------------------------------------------------- SHUTDOWN METHODS -------------------------------------------------------
//-----------------------------------------------------------------------------------------------------------------------------
/// method removing all created materials
int AppWorldLogic::clearMaterials()
{
	materials->removeMaterial(materials->findMaterial("my_mesh_base0")->getGUID());
	materials->removeMaterial(materials->findMaterial("my_mesh_base1")->getGUID());
	materials->removeMaterial(materials->findMaterial("my_mesh_base2")->getGUID());
	materials->removeMaterial(materials->findMaterial("my_mesh_base3")->getGUID());

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
/// method removing all  created objects
int AppWorldLogic::removeObjects()
{
	while (Objects.size() > 0)
	{
		removeMeshFromScene(Objects.begin()->get()->getName());
	}

	return 1;
}
//-----------------------------------------------------------------------------------------------------------------------------
AppWorldLogic::AppWorldLogic() {
	
}

AppWorldLogic::~AppWorldLogic() {
	
}

int AppWorldLogic::init() {
	// Write here code to be called on world initialization: initialize resources for your world scene during the world start.
	
	// getting a pointer to the application
	app = App::get();

	// initializing pseudo-random number generator
	Game::get()->setSeed(time(NULL));

	// getting a pointer to the Editor
	editor = Editor::get();

	// creating materials
	initMaterials();

	// creating properties
	initProperties();

	// creating objects
	initObjects();

	// creating a player
	initPlayer();

	// creating lights
	initLights();
	
	return 1;
}

// start of the main loop
int AppWorldLogic::update() {
	// Write here code to be called before updating each render frame: specify all graphics-related functions you want to be called every frame while your application executes.

	// getting an inverse FPS value (the time in seconds it took to complete the last frame)
	ifps = Game::get()->getIFps();

	// checking if it's time to change current scale and forward vector direction of our objects
	if (elapsed_time < 0.0f)
	{
		// change current scaling vector for objects
		current_objects_scale = Math::vec3(Game::get()->getRandomFloat(0.8f, 1.2f));

		// change forward direction for objects
		forward_direction = forward_direction * Math::rotateZ(60.0f);

		// resetting elapsed time counter
		elapsed_time = CHANGE_INTERVAL;
	}
	
	// decreasing the time counter to the next change of current scale and forward vector direction
	elapsed_time -= ifps;

	// if right mouse button is clicked
	if (app->getMouseButtonState(App::BUTTON_RIGHT))
	{
		// get and select object under the mouse cursor
		selectObject(getObjectUnderMouseCursor(Game::get()->getPlayer(), app->getMouseX(), app->getMouseY(), 100.0f), old_selection);
	}

	// closing the application if a 'Q' key is pressed, ignoring the key if the console is opened
	if (app->getKeyState('q') && !Console::get()->getActivity())
	{
		app->exit();
	}

	// updating objects
	updateObjects();

	// updating lights
	updateLights();

	return 1;
}

int AppWorldLogic::render() {
	// The engine calls this function before rendering each render frame: correct behavior after the state of the node has been updated.
	
	return 1;
}

int AppWorldLogic::flush() {
	// Write here code to be called before updating each physics frame: control physics in your application and put non-rendering calculations.
	// The engine calls flush() with the fixed rate (60 times per second by default) regardless of the FPS value.
	// WARNING: do not create, delete or change transformations of nodes here, because rendering is already in progress.
	
	return 1;
}
// end of the main loop

int AppWorldLogic::shutdown() {
// Write here code to be called on world shutdown: delete resources that were created during world script execution to avoid memory leaks.
		
	// deleting all created nodes
	removeObjects();

	// clearing the player pointer
	player.clear();

	// clearing light sources
	thesun.clear();
	light_omni.clear();
	projector.clear();

	// clearing all created materials
	clearMaterials();

	// resetting old_selection pointer
	old_selection.clear();

	return 1;
}

int AppWorldLogic::destroy() {
	// Write here code to be called when the video mode is changed or the application is restarted (i.e. video_restart is called). It is used to reinitialize the graphics context.
	
	return 1;
}

int AppWorldLogic::save(const Unigine::StreamPtr &stream) {
	// Write here code to be called when the world is saving its state (i.e. state_save is called): save custom user data to a file.
	
	UNIGINE_UNUSED(stream);
	return 1;
}

int AppWorldLogic::restore(const Unigine::StreamPtr &stream) {
	// Write here code to be called when the world is restoring its state (i.e. state_restore is called): restore custom user data to a file here.
	
	UNIGINE_UNUSED(stream);
	return 1;
}