QuadTreeVector/main.cpp

/*
	Quirky Quad Trees Part #1 - Static Quad Tree Implementation
	"War... huh... What is it good for? Absolutely nothin..." - javidx9
	
	License (OLC-3)
	~~~~~~~~~~~~~~~
	Copyright 2018 - 2022 OneLoneCoder.com

	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions
	are met:

	1. Redistributions or derivations of source code must retain the above
	copyright notice, this list of conditions and the following disclaimer.

	2. Redistributions or derivative works in binary form must reproduce
	the above copyright notice. This list of conditions and the following
	disclaimer must be reproduced in the documentation and/or other
	materials provided with the distribution.

	3. Neither the name of the copyright holder nor the names of its
	contributors may be used to endorse or promote products derived
	from this software without specific prior written permission.
	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	
	Video:
	~~~~~~
	https://youtu.be/ASAowY6yJII

	Pan & Zoom with middle mouse, TAB to switch between methods
	
	Links
	~~~~~
	YouTube:	https://www.youtube.com/javidx9
				https://www.youtube.com/javidx9extra
	Discord:	https://discord.gg/WhwHUMV
	Twitter:	https://www.twitter.com/javidx9
	Twitch:		https://www.twitch.tv/javidx9
	GitHub:		https://www.github.com/onelonecoder
	Homepage:	https://www.onelonecoder.com
	
	Author
	~~~~~~
	David Barr, aka javidx9, <EFBFBD>OneLoneCoder 2019, 2020, 2021, 2022
*/


#define OLC_PGE_APPLICATION
#include "pixelGameEngine.h"

#define OLC_PGEX_TRANSFORMEDVIEW
#include "transformedView.h"

#include "quadtree.h"

// The Example!
class Example_StaticQuadTree : public olc::PixelGameEngine
{
public:
	Example_StaticQuadTree()
	{
		sAppName = "Static QuadTree";
	}

protected:
	olc::TransformedView tv;

	// An example object of something in 2D space
	struct SomeObjectWithArea
	{
		olc::vf2d vPos;
		olc::vf2d vVel;
		olc::vf2d vSize;
		olc::Pixel colour;
	};

	// A regular list of the objects
	std::list<SomeObjectWithArea> vecObjects;

	// An equivalent quad tree of the objects
	olc::utils::QuadTreeContainer<SomeObjectWithArea> treeObjects;

	// The "length" of one side of the "world" the objects reside in
	float fArea = 100000.0f;

	bool bUseQuadTree = true;

public:
	bool OnUserCreate() override
	{
		// Transform View - enables Pan & Zoom
		tv.Initialise({ ScreenWidth(), ScreenHeight() });

		// Create the tree, and size it to the world
		treeObjects.resize(olc::utils::geom2d::rect<float>({ 0.0f, 0.0f }, { fArea, fArea }));


		// Dirty random float generator
		auto rand_float = [](const float a, const float b)
		{
			return float(rand()) / float(RAND_MAX) * (b - a) + a;
		};


		// Create 1,000,000 objects, push into both containers (so 2,000,000 I suppose :P )
		for (int i = 0; i < 1000000; i++)
		{
			SomeObjectWithArea ob;
			ob.vPos = { rand_float(0.0f, fArea), rand_float(0.0f, fArea) };
			ob.vSize = { rand_float(0.1f, 100.0f), rand_float(0.1f, 100.0f) };
			ob.colour = olc::Pixel(rand() % 256, rand() % 256, rand() % 256);

			treeObjects.insert(ob, olc::utils::geom2d::rect(ob.vPos, ob.vSize));
			vecObjects.push_back(ob);
		}

		return true;
	}

	bool OnUserUpdate(float fElapsedTime) override
	{
		// Tab switches between modes
		if (GetKey(olc::Key::TAB).bPressed)
			bUseQuadTree = !bUseQuadTree;

		tv.HandlePanAndZoom();

		// Get rectangle that equates to screen in world space
		olc::utils::geom2d::rect rScreen = { tv.GetWorldTL(), tv.GetWorldBR() - tv.GetWorldTL() };
		size_t nObjectCount = 0;

		if (bUseQuadTree)
		{
			// QUAD TREE MODE
			auto tpStart = std::chrono::system_clock::now();

			// Use search function to return list of pointers to objects in that area
			for (const auto& object : treeObjects.search(rScreen))
			{
				tv.FillRectDecal(object->item.vPos, object->item.vSize, object->item.colour);
				nObjectCount++;
			}
			std::chrono::duration<float> duration = std::chrono::system_clock::now() - tpStart;


			std::string sOutput = "Quadtree " + std::to_string(nObjectCount) + "/" + std::to_string(vecObjects.size()) + " in " + std::to_string(duration.count());
			DrawStringDecal({ 4, 4 }, sOutput, olc::BLACK, { 4.0f, 8.0f });
			DrawStringDecal({ 2, 2 }, sOutput, olc::WHITE, { 4.0f, 8.0f });

		}
		else
		{
			// LINEAR SEARCH MODE
			auto tpStart = std::chrono::system_clock::now();

			// Blindly check all objects to see if they overlap with screen
			for (const auto& object : vecObjects)
			{
				if (olc::utils::geom2d::overlaps(rScreen,olc::utils::geom2d::rect<float>{ object.vPos, object.vSize }))
				{
					tv.FillRectDecal(object.vPos, object.vSize, object.colour);
					nObjectCount++;
				}
			}
			std::chrono::duration<float> duration = std::chrono::system_clock::now() - tpStart;

			std::string sOutput = "Linear " + std::to_string(nObjectCount) + "/" + std::to_string(vecObjects.size()) + " in " + std::to_string(duration.count());
			DrawStringDecal({ 4, 4 }, sOutput, olc::BLACK, { 4.0f, 8.0f });
			DrawStringDecal({ 2, 2 }, sOutput, olc::WHITE, { 4.0f, 8.0f });
		}

		return true;
	}
};


int main()
{
	Example_StaticQuadTree demo;
	if (demo.Construct(1280, 960, 1, 1, false, false))
		demo.Start();
	return 0;
}