MigRay 1.03 - now with strafing

#include <iostream>
#include <Windows.h>
#include <time.h>       /* clock_t, clock, CLOCKS_PER_SEC */
#include <math.h>       /* sqrt */

using namespace std;

//use these chars for depth: from # to N to V to / on one set, and % to & to : to . on the other

//globals
//engine--------------------------------------------------------------
#define MAP_WIDTH 32
#define MAP_HEIGHT 32

#define SCREEN_WIDTH 72
#define SCREEN_HEIGHT 72


int worldMap[MAP_HEIGHT][MAP_WIDTH] =
{
    {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},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,1,1,1,1,1,1,1},
    {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},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {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}
};


char screenMap[SCREEN_HEIGHT][SCREEN_WIDTH];


//game--------------------------------------
bool running;

clock_t oldTime = 0;
clock_t frameTime = 0;


//player------------------------------------
double playerPosX = (MAP_WIDTH/2), playerPosY = (MAP_HEIGHT/2); //spawn in middle of map
double playerDirX = -1, playerDirY = 0; //initial direction vector
double planeX = 0, planeY = 0.66; //2d raycaster version of camera plane
double moveSpeed;
double rotSpeed;


//functions---------------------------------
void init();
void gameLoop();
void updatePos();
void updateWorld();
void drawScreen();
void writeToBuffer();
void printScreen();
int getTime();
float getFPS();
void getInput();
void movement();


//main program-------------------------------------------------------------
int main()
{
    init();

    gameLoop();

    cin.get();

    return 0;
}


//initialise (load map, spawn player, etc.)--------------------------------
void init()
{
    running = true;
}


void gameLoop()
{
    while(running)
    {
        updatePos();
        updateWorld();
        drawScreen();
        printScreen();
        getInput();
    }
}


void updatePos()
{

}


void updateWorld()
{

}


void drawScreen()
{
    for(int x = 0; x < SCREEN_WIDTH; x++)
    {
        //calculate ray position and direction
        double cameraX = 2 * x / double(SCREEN_WIDTH) - 1; //x-coordinate in camera space
        double rayPosX = playerPosX;
        double rayPosY = playerPosY;
        double rayDirX = playerDirX + planeX * cameraX;
        double rayDirY = playerDirY + planeY * cameraX;


        //which box of the map we're in
        int mapX = int(rayPosX);
        int mapY = int(rayPosY);

        //length of ray from current position to next x or y-side
        double sideDistX;
        double sideDistY;

        //length of ray from one x or y-side to next x or y-side
        double deltaDistX = sqrt(1 + (rayDirY * rayDirY) / (rayDirX * rayDirX));
        double deltaDistY = sqrt(1 + (rayDirX * rayDirX) / (rayDirY * rayDirY));
        double perpWallDist;

        //what direction to step in x or y-direction (either +1 or -1)
        int stepX;
        int stepY;

        int hit = 0; //was there a wall hit?
        int side; //was a NS or a EW wall hit?


        //calculate step and initial sideDist
        if (rayDirX < 0)
        {
            stepX = -1;
            sideDistX = (rayPosX - mapX) * deltaDistX;
        }
        else
        {
            stepX = 1;
            sideDistX = (mapX + 1.0 - rayPosX) * deltaDistX;
        }
        if (rayDirY < 0)
        {
            stepY = -1;
            sideDistY = (rayPosY - mapY) * deltaDistY;
        }
        else
        {
            stepY = 1;
            sideDistY = (mapY + 1.0 - rayPosY) * deltaDistY;
        }


        //perform DDA
        while (hit == 0)
        {
            //jump to next map square, in x-direction, OR in y-direction
            if (sideDistX < sideDistY)
            {
                sideDistX += deltaDistX;
                mapX += stepX;
                side = 0;
            }

            else
            {
                sideDistY += deltaDistY;
                mapY += stepY;
                side = 1;
            }
            //Check if ray has hit a wall
            if (worldMap[mapX][mapY] > 0) hit = 1;
        }


        //Calculate distance projected on camera direction (oblique distance will give fisheye effect!)
        if (side == 0)
        perpWallDist = fabs((mapX - rayPosX + (1 - stepX) / 2) / rayDirX);
        else
        perpWallDist = fabs((mapY - rayPosY + (1 - stepY) / 2) / rayDirY);


        //Calculate height of line to draw on screen
        int lineHeight = abs(int(SCREEN_HEIGHT / perpWallDist));

        //calculate lowest and highest char to fill in current stripe
        int drawStart = -lineHeight / 2 + SCREEN_HEIGHT / 2;
        if(drawStart < 0)drawStart = 0;
        int drawEnd = lineHeight / 2 + SCREEN_HEIGHT / 2;
        if(drawEnd >= SCREEN_HEIGHT)drawEnd = SCREEN_HEIGHT - 1;


        //choose wall color
        //ColorRGB color;
        switch(worldMap[mapX][mapY])
        {
            case 1:  'M';  break;
            case 2:  '#';  break;
            case 3:  '=';   break;
            case 4:  '-';  break;
            default: '0'; break;
        }

        //give x and y sides different brightness
        //if (side == 1) {color = color / 2;}

        //draw the pixels of the stripe as a vertical line
        //verLine(x, drawStart, drawEnd, color);

        for(int y = 0; y < SCREEN_HEIGHT; y++)
        {
            if(y >= drawStart && y <= drawEnd)
            {
                screenMap[x][y] = '#';

                if(side == 1) screenMap[x][y] = '%';
            }
            else screenMap[x][y] = ' ';
        }
    }

    writeToBuffer();
}


void writeToBuffer()
{
    HANDLE hOutput = (HANDLE)GetStdHandle( STD_OUTPUT_HANDLE );

    COORD dwBufferSize = { SCREEN_WIDTH,SCREEN_HEIGHT };
    COORD dwBufferCoord = { 0, 0 };
    SMALL_RECT rcRegion = { 0, 0, SCREEN_WIDTH-1, SCREEN_HEIGHT-1 };

    CHAR_INFO buffer[SCREEN_HEIGHT][SCREEN_WIDTH];

    ReadConsoleOutput( hOutput, (CHAR_INFO *)buffer, dwBufferSize,
    dwBufferCoord, &rcRegion );

    for(int y = 0; y < SCREEN_HEIGHT; y++)
    {
        for(int x = 0; x < SCREEN_WIDTH; x++)
        {
            buffer[y][x].Char.AsciiChar = screenMap[x][y];
            buffer[y][x].Attributes = 0x0E;
        }
    }

    /*buffer[5][11].Char.AsciiChar = 'i';
    buffer[5][11].Attributes = 0x0B;
    buffer[5][12].Char.AsciiChar = '!';
    buffer[5][12].Attributes = 0x0A;*/

    system ("CLS");

    WriteConsoleOutput( hOutput, (CHAR_INFO *)buffer, dwBufferSize,
    dwBufferCoord, &rcRegion );
}


void printScreen()
{
    /*
    for(int y = 0; y < SCREEN_HEIGHT; y++)
    {
        for(int x = 0; x < SCREEN_WIDTH; x++)
        {
            cout << screenMap[x][y];
        }

        cout << endl;
    }*/

    cout << "Time Elapsed: " << getTime() << " seconds" << endl;
    cout << "move speed: " << float(moveSpeed) << "\tposition: " << playerPosX << ", " << playerPosY << endl;
    cout << /*"rot speed: " << float(rotSpeed) <<*/ "\trotation: " << playerDirX << ", " << playerDirY << endl;
    cout << "FPS " << (1.0 / getFPS());
}


int getTime()
{
    oldTime = frameTime;

    frameTime = clock();

    float time = ((float)frameTime)/CLOCKS_PER_SEC;

    //speed modifiers
    moveSpeed = ((frameTime - oldTime) / 1000.0) * 3; //the constant value is in squares/second
    rotSpeed = ((frameTime - oldTime) / 1000.0) * 1.25; //the constant value is in radians/second

    return time;
}


float getFPS()
{
    return (frameTime - oldTime) * 1000;
}


void getInput()
{
    //move forward if no wall in front of you
    if (GetAsyncKeyState(0x57))
    {
      if(worldMap[int(playerPosX + playerDirX * moveSpeed)][int(playerPosY)] == false) playerPosX += playerDirX * moveSpeed;
      if(worldMap[int(playerPosX)][int(playerPosY + playerDirY * moveSpeed)] == false) playerPosY += playerDirY * moveSpeed;
    }
    //move backwards if no wall behind you
    if (GetAsyncKeyState(0x53))
    {
      if(worldMap[int(playerPosX - playerDirX * moveSpeed)][int(playerPosY)] == false) playerPosX -= playerDirX * moveSpeed;
      if(worldMap[int(playerPosX)][int(playerPosY - playerDirY * moveSpeed)] == false) playerPosY -= playerDirY * moveSpeed;
    }
    //strafe left if no wall left of you
    if (GetAsyncKeyState(0x41))
    {
      if(worldMap[int(playerPosX + (-playerDirY) * moveSpeed)][int(playerPosY)] == false) playerPosX += (-playerDirY) * moveSpeed;
      if(worldMap[int(playerPosX)][int(playerPosY + playerDirX * moveSpeed)] == false) playerPosY += playerDirX * moveSpeed;
    }
    //strafe right if no wall right of you
    if (GetAsyncKeyState(0x44))
    {
      if(worldMap[int(playerPosX + playerDirY * moveSpeed)][int(playerPosY)] == false) playerPosX += playerDirY * moveSpeed;
      if(worldMap[int(playerPosX)][int(playerPosY + (-playerDirX) * moveSpeed)] == false) playerPosY += (-playerDirX) * moveSpeed;
    }
    //rotate to the right
    if (GetAsyncKeyState(VK_RIGHT))
    {
      //both camera direction and camera plane must be rotated
      double oldDirX = playerDirX;
      playerDirX = playerDirX * cos(-rotSpeed) - playerDirY * sin(-rotSpeed);
      playerDirY = oldDirX * sin(-rotSpeed) + playerDirY * cos(-rotSpeed);
      double oldPlaneX = planeX;
      planeX = planeX * cos(-rotSpeed) - planeY * sin(-rotSpeed);
      planeY = oldPlaneX * sin(-rotSpeed) + planeY * cos(-rotSpeed);
    }
    //rotate to the left
    if (GetAsyncKeyState(VK_LEFT))
    {
      //both camera direction and camera plane must be rotated
      double oldDirX = playerDirX;
      playerDirX = playerDirX * cos(rotSpeed) - playerDirY * sin(rotSpeed);
      playerDirY = oldDirX * sin(rotSpeed) + playerDirY * cos(rotSpeed);
      double oldPlaneX = planeX;
      planeX = planeX * cos(rotSpeed) - planeY * sin(rotSpeed);
      planeY = oldPlaneX * sin(rotSpeed) + planeY * cos(rotSpeed);
    }
    movement();
}


void movement()
{

}