RayTracing3D.cpp

// RayTracing3D.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#define OLC_PGE_APPLICATION
#include <iostream>
#include <ctime>  
#include <cmath>
#include "olcPixelGameEngine.h"


int screenRatio = 4;
int screenWidth = 1280 / screenRatio;
int screenHeight = 720 / screenRatio;

int mapSize = 32;
float playerX = 8;
float playerY = 8;
float playerAngle = 0;
float FOV = 3.14159 / 5.0f;
float farPlane = std::sqrtf(std::powf(mapSize, 2.0f));
float movementSpeed = 5;
float distanceQuility = 0.01f;

int map[32][32] =
{
	{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1},
	{1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1},
	{1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1},
	{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},
	{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},
};

auto start = std::chrono::system_clock::now();
// Some computation here
auto end = std::chrono::system_clock::now();

olc::Sprite sprite;

// Override base class with your custom functionality
class Example : public olc::PixelGameEngine
{
public:
	Example()
	{
		sAppName = "Example";
	}
private:
	olc::Sprite *wallTexture;
public:
	bool OnUserCreate() override
	{
		wallTexture = new olc::Sprite();
		// Called once at the start, so create things here
		return true;
	}
	bool OnUserUpdate(float fElapsedTime) override
	{
		start = std::chrono::system_clock::now();
		std::chrono::duration<float> elapsedTimeClock = end - start;
		end = start;
		float elapsedTime = -elapsedTimeClock.count();

		float tempX = playerX, tempY = playerY;

		if (GetKey(olc::Key::E).bHeld)
			playerAngle += 1.1f * elapsedTime;
		if (GetKey(olc::Key::Q).bHeld)
			playerAngle -= 1.1f * elapsedTime;
		if (GetKey(olc::Key::W).bHeld)
		{
			tempX += sinf(playerAngle) * movementSpeed * elapsedTime;
			tempY += cosf(playerAngle) * movementSpeed * elapsedTime;
		}
		if (GetKey(olc::Key::D).bHeld)
		{
			tempX += sinf(playerAngle + (90 * 3.14159 / 180)) * movementSpeed * elapsedTime;
			tempY += cosf(playerAngle + (90 * 3.14159 / 180)) * movementSpeed * elapsedTime;
		}
		if (GetKey(olc::Key::A).bHeld)
		{
			tempX += sinf(playerAngle - (90 * 3.14159 / 180)) * movementSpeed * elapsedTime;
			tempY += cosf(playerAngle - (90 * 3.14159 / 180)) * movementSpeed * elapsedTime;
		}
		if (GetKey(olc::Key::S).bHeld)
		{
			tempX -= sinf(playerAngle) * movementSpeed * elapsedTime;
			tempY -= cosf(playerAngle) * movementSpeed * elapsedTime;
		}
		if (!map[(int)tempX][(int)tempY])
		{
			playerX = tempX;
			playerY = tempY;
		}
		

		for (int x = 0; x < screenWidth; x++)
		{
			float rayAngle = (playerAngle - FOV / 2) + ((float)x / (float)screenWidth) * FOV;
			float distanceToWall = 0.0f;
			bool hitWall = false;
			float unitVectorX = sinf(rayAngle);
			float unitVectorY = cosf(rayAngle);

			while (!hitWall && distanceToWall < farPlane)
			{
				distanceToWall += distanceQuility;

				hitWall = RayHitWall(unitVectorX, unitVectorY, distanceToWall);
			}

			if (distanceToWall >= farPlane)
				distanceToWall = screenHeight / 2;

			int ceilingSize = (float)(screenHeight / 1.8) - screenWidth / distanceToWall;
			int floorSize = screenHeight - ceilingSize;
			float shading = 255 - ((distanceToWall / farPlane) * 255);


			for (int y = 0; y < screenHeight; y++)
			{
				if (y <= ceilingSize)
					Draw(x, y, olc::BLUE);
				else if (y > ceilingSize && y <= floorSize)
					Draw(x, y, olc::Pixel(shading, shading, shading));
				else
				{
					Draw(x, y, olc::YELLOW);
				}
			}
		}

		return true;
	}

	bool RayHitWall(float unitVectorX, float unitVectorY, float distanceToWall)
	{
		bool hitWall = false;
		int testRayX = (int)(playerX + unitVectorX * distanceToWall);
		int testRayY = (int)(playerY + unitVectorY * distanceToWall);

		if (testRayX < 0 || testRayX >= mapSize || testRayY < 0 || testRayY >= mapSize)
		{
			hitWall = true;
			distanceToWall = farPlane;
		}
		else if (map[(int)testRayX][(int)testRayY] == 1)
		{
			hitWall = true;
		}
		return hitWall;
	}
};


int main()
{
	Example demo;
	if (demo.Construct(screenWidth, screenHeight, screenRatio, screenRatio))
		demo.Start();
	return 0;
}