Simple L-System with Irrlicht render

gistfile1.cpp

#include <irrlicht.h>
#include <vector>
#include <iostream>
#include <stack>
#include <map>
#include <functional>

using namespace irr;
using namespace core;
using namespace scene;
using namespace video;
using namespace io;
using namespace gui;

struct State
{
	vector3df rotate;
	vector3df prevPoint;

	State() : rotate(vector3df()) {}
	State(const State& other) : rotate(other.rotate), prevPoint(other.prevPoint) { }
};

typedef std::vector<line3df> Lines;
typedef std::stack<State> States;
typedef std::map<char, std::string> Rules;

typedef std::function< void() > ActionFunction;
typedef std::map<char, ActionFunction> Actions;

int main()
{
	IrrlichtDevice *device = createDevice(EDT_DIRECT3D9, dimension2d<u32>(1024, 576));
	IVideoDriver* driver = device->getVideoDriver();
	ISceneManager* smgr = device->getSceneManager();

	ICameraSceneNode* camera = smgr->addCameraSceneNodeFPS();
	ISceneNode* root = smgr->addEmptySceneNode();
	ILightSceneNode* light = smgr->addLightSceneNode();

	light->setPosition(vector3df(100, 100, 100));
	light->setRadius(1000);

	camera->setPosition(vector3df(40, 40, 40));
	camera->setTarget(vector3df(0, 0, 0));

	//////
	std::string command;
	Lines lines;
	Rules rules;
	Actions actions;

	// Start data
	command = "F";
	rules['F'] = "F[+F]F[-F][F]";
	float angle = 20;

	State currentState;
	States states;

	states.push(currentState);

	vector3df point;

	actions['F'] = [&states, &lines]()
	{
		vector3df point = states.top().prevPoint + vector3df(0, 10, 0);

		point.rotateYZBy(states.top().rotate.X, states.top().prevPoint);
		point.rotateXZBy(states.top().rotate.Y, states.top().prevPoint);
		point.rotateXYBy(states.top().rotate.Z, states.top().prevPoint);

		lines.push_back(line3df(point, states.top().prevPoint));
		states.top().prevPoint = point;
	};

	actions['+'] = [&states, &angle](){ states.top().rotate.X += angle; };
	actions['-'] = [&states, &angle](){ states.top().rotate.X -= angle; };

	actions['&'] = [&states, &angle](){ states.top().rotate.Y += angle; };
	actions['^'] = [&states, &angle](){ states.top().rotate.Y -= angle; };

	actions['\\'] = [&states, &angle](){ states.top().rotate.Z += angle; };
	actions['/'] = [&states, &angle](){ states.top().rotate.Z -= angle; };

	actions['['] = [&states, &angle](){ states.push(State(states.top())); };
	actions[']'] = [&states, &angle](){ states.pop(); };

	for(int i = 0; i < 5; ++i)
	{
		std::string temp = "";

		for(auto it = command.begin(); it != command.end(); ++it)
		{
			if(actions.find(*it) != actions.end())
				actions[*it]();

			if(rules.find(*it) != rules.end())
				temp += rules[*it];
			else
				temp += *it;
		}

		command = temp;
	}

	for(auto it = command.begin(); it != command.end(); ++it)
	{
		if(actions.find(*it) != actions.end())
			actions[*it]();
	}

	//////

	while(device->run())
	{
		driver->beginScene();

		smgr->drawAll();

		SMaterial material;
		material.Lighting = false;
		driver->setMaterial(material);

		for(auto it = lines.begin(); it != lines.end(); ++it)
		{
			driver->draw3DLine((*it).start, (*it).end);
		}

		driver->endScene();
	}

	device->closeDevice();

	return 0;
}