# cmd_game_engine.cpp

/*
# cmd_game_engine.cpp

OneLoneCoder.com - Command Line Game Engine
"Who needs a frame buffer?" - @Javidx9

The Original & Best :P

One Lone Coder License
~~~~~~~~~~~~~~~~~~~~~~
- This software is Copyright (C) 2018 Javidx9
- This is free software
- This software comes with absolutely no warranty
- The copyright holder is not liable or responsible for anything
  this software does or does not
- You use this software at your own risk
- You can distribute this software
- You can modify this software
- Redistribution of this software or a derivative of this software
  must attribute the Copyright holder named above, in a manner
  visible to the end user

License
~~~~~~~
One Lone Coder Console Game Engine  Copyright (C) 2018  Javidx9
This program comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to redistribute it
under certain conditions; See license for details.

Original works located at:
    https://www.github.com/onelonecoder
    https://www.onelonecoder.com
    https://www.youtube.com/javidx9

GNU GPLv3
    https://github.com/OneLoneCoder/videos/blob/master/LICENSE

From Javidx9 :)
~~~~~~~~~~~~~~~
Hello! Ultimately I don't care what you use this for. It's intended to be
educational, and perhaps to the oddly minded - a little bit of fun.
Please hack this, change it and use it in any way you see fit. You acknowledge
that I am not responsible for anything bad that happens as a result of
your actions. However this code is protected by GNU GPLv3, see the license in the
github repo. This means you must attribute me if you use it. You can view this
license here: https://github.com/OneLoneCoder/videos/blob/master/LICENSE

Cheers!

Background
~~~~~~~~~~
If you've seen any of my videos - I like to do things using the windows console. It's quick
and easy, and allows you to focus on just the code that matters - ideal when you're
experimenting. Thing is, I have to keep doing the same initialisation and display code
each time, so this class wraps that up.

Author
~~~~~~
Twitter: @javidx9   http://twitter.com/javidx9
Blog:               http://www.onelonecoder.com
YouTube:            http://www.youtube.com/javidx9

Videos:
~~~~~~
Original:               https://youtu.be/cWc0hgYwZyc
Added mouse support:    https://youtu.be/tdqc9hZhHxM
Beginners Guide:        https://youtu.be/u5BhrA8ED0o

Shout Outs!
~~~~~~~~~~~
Thanks to cool people who helped with testing, bug-finding and fixing!
wowLinh, JavaJack59, idkwid, kingtatgi, Return Null, CPP Guy, MaGetzUb

Last Updated: 02/07/2018

Usage:
~~~~~~
This class is abstract, so you must inherit from it. Override the OnUserCreate() function
with all the stuff you need for your application (for thready reasons it's best to do
this in this function and not your class constructor). Override the OnUserUpdate(float fElapsedTime)
function with the good stuff, it gives you the elapsed time since the last call so you
can modify your stuff dynamically. Both functions should return true, unless you need
the application to close.

    int main()
    {
        // Use olcConsoleGameEngine derived app
        OneLoneCoder_Example game;

        // Create a console with resolution 160x100 characters
        // Each character occupies 8x8 pixels
        game.ConstructConsole(160, 100, 8, 8);

        // Start the engine!
        game.Start();

        return 0;
    }

Input is also handled for you - interrogate the m_keys[] array with the virtual
keycode you want to know about. bPressed is set for the frame the key is pressed down
in, bHeld is set if the key is held down, bReleased is set for the frame the key
is released in. The same applies to mouse! m_mousePosX and Y can be used to get
the current cursor position, and m_mouse[1..5] returns the mouse buttons.

The draw routines treat characters like pixels. By default they are set to white solid
blocks - but you can draw any unicode character, using any of the colours listed below.

There may be bugs!

See my other videos for examples!
http://www.youtube.com/javidx9

Lots of programs to try:
http://www.github.com/OneLoneCoder/videos

Chat on the Discord server:
https://discord.gg/WhwHUMV

Be bored by Twitch:
http://www.twitch.tv/javidx9

*/

#pragma once
#pragma comment(lib, "winmm.lib")

#ifndef UNICODE
#error Please enable UNICODE for your compiler! VS: Project Properties -> General -> \
Character Set -> Use Unicode. Thanks! - Javidx9
#endif

#include <windows.h>

#include <iostream>
#include <chrono>
#include <vector>
#include <list>
#include <thread>
#include <atomic>
#include <condition_variable>

enum COLOUR
{
    FG_BLACK        = 0x0000,
    FG_DARK_BLUE    = 0x0001,
    FG_DARK_GREEN   = 0x0002,
    FG_DARK_CYAN    = 0x0003,
    FG_DARK_RED     = 0x0004,
    FG_DARK_MAGENTA = 0x0005,
    FG_DARK_YELLOW  = 0x0006,
    FG_GREY         = 0x0007, // Thanks MS :-/
    FG_DARK_GREY    = 0x0008,
    FG_BLUE         = 0x0009,
    FG_GREEN        = 0x000A,
    FG_CYAN         = 0x000B,
    FG_RED          = 0x000C,
    FG_MAGENTA      = 0x000D,
    FG_YELLOW       = 0x000E,
    FG_WHITE        = 0x000F,
    BG_BLACK        = 0x0000,
    BG_DARK_BLUE    = 0x0010,
    BG_DARK_GREEN   = 0x0020,
    BG_DARK_CYAN    = 0x0030,
    BG_DARK_RED     = 0x0040,
    BG_DARK_MAGENTA = 0x0050,
    BG_DARK_YELLOW  = 0x0060,
    BG_GREY         = 0x0070,
    BG_DARK_GREY    = 0x0080,
    BG_BLUE         = 0x0090,
    BG_GREEN        = 0x00A0,
    BG_CYAN         = 0x00B0,
    BG_RED          = 0x00C0,
    BG_MAGENTA      = 0x00D0,
    BG_YELLOW       = 0x00E0,
    BG_WHITE        = 0x00F0,
};

enum PIXEL_TYPE
{
    PIXEL_SOLID = 0x2588,
    PIXEL_THREEQUARTERS = 0x2593,
    PIXEL_HALF = 0x2592,
    PIXEL_QUARTER = 0x2591,
};

class olcSprite
{
public:
    olcSprite()
    {

    }

    olcSprite(int w, int h)
    {
        Create(w, h);
    }

    olcSprite(std::wstring sFile)
    {
        if (!Load(sFile))
            Create(8, 8);
    }

    int nWidth = 0;
    int nHeight = 0;

private:
    short *m_Glyphs = nullptr;
    short *m_Colours = nullptr;

    void Create(int w, int h)
    {
        nWidth = w;
        nHeight = h;
        m_Glyphs = new short[w*h];
        m_Colours = new short[w*h];
        for (int i = 0; i < w*h; i++)
        {
            m_Glyphs[i] = L' ';
            m_Colours[i] = FG_BLACK;
        }
    }

public:
    void SetGlyph(int x, int y, short c)
    {
        if (x <0 || x >= nWidth || y < 0 || y >= nHeight)
            return;
        else
            m_Glyphs[y * nWidth + x] = c;
    }

    void SetColour(int x, int y, short c)
    {
        if (x <0 || x >= nWidth || y < 0 || y >= nHeight)
            return;
        else
            m_Colours[y * nWidth + x] = c;
    }

    short GetGlyph(int x, int y)
    {
        if (x <0 || x >= nWidth || y < 0 || y >= nHeight)
            return L' ';
        else
            return m_Glyphs[y * nWidth + x];
    }

    short GetColour(int x, int y)
    {
        if (x <0 || x >= nWidth || y < 0 || y >= nHeight)
            return FG_BLACK;
        else
            return m_Colours[y * nWidth + x];
    }

    short SampleGlyph(float x, float y)
    {
        int sx = (int)(x * (float)nWidth);
        int sy = (int)(y * (float)nHeight-1.0f);
        if (sx <0 || sx >= nWidth || sy < 0 || sy >= nHeight)
            return L' ';
        else
            return m_Glyphs[sy * nWidth + sx];
    }

    short SampleColour(float x, float y)
    {
        int sx = (int)(x * (float)nWidth);
        int sy = (int)(y * (float)nHeight-1.0f);
        if (sx <0 || sx >= nWidth || sy < 0 || sy >= nHeight)
            return FG_BLACK;
        else
            return m_Colours[sy * nWidth + sx];
    }

    bool Save(std::wstring sFile)
    {
        FILE *f = nullptr;
        _wfopen_s(&f, sFile.c_str(), L"wb");
        if (f == nullptr)
            return false;

        fwrite(&nWidth, sizeof(int), 1, f);
        fwrite(&nHeight, sizeof(int), 1, f);
        fwrite(m_Colours, sizeof(short), nWidth * nHeight, f);
        fwrite(m_Glyphs, sizeof(short), nWidth * nHeight, f);

        fclose(f);

        return true;
    }

    bool Load(std::wstring sFile)
    {
        delete[] m_Glyphs;
        delete[] m_Colours;
        nWidth = 0;
        nHeight = 0;

        FILE *f = nullptr;
        _wfopen_s(&f, sFile.c_str(), L"rb");
        if (f == nullptr)
            return false;

        std::fread(&nWidth, sizeof(int), 1, f);
        std::fread(&nHeight, sizeof(int), 1, f);

        Create(nWidth, nHeight);

        std::fread(m_Colours, sizeof(short), nWidth * nHeight, f);
        std::fread(m_Glyphs, sizeof(short), nWidth * nHeight, f);

        std::fclose(f);
        return true;
    }
};

class olcConsoleGameEngine
{
public:
    olcConsoleGameEngine()
    {
        m_nScreenWidth = 80;
        m_nScreenHeight = 30;

        m_hConsole = GetStdHandle(STD_OUTPUT_HANDLE);
        m_hConsoleIn = GetStdHandle(STD_INPUT_HANDLE);

        std::memset(m_keyNewState, 0, 256 * sizeof(short));
        std::memset(m_keyOldState, 0, 256 * sizeof(short));
        std::memset(m_keys, 0, 256 * sizeof(sKeyState));
        m_mousePosX = 0;
        m_mousePosY = 0;

        m_bEnableSound = false;

        m_sAppName = L"Default";
    }

    void EnableSound()
    {
        m_bEnableSound = true;
    }

    int ConstructConsole(int width, int height, int fontw, int fonth)
    {
        if (m_hConsole == INVALID_HANDLE_VALUE)
            return Error(L"Bad Handle");

        m_nScreenWidth = width;
        m_nScreenHeight = height;

        // Update 13/09/2017 - It seems that the console behaves differently on some systems
        // and I'm unsure why this is. It could be to do with windows default settings, or
        // screen resolutions, or system languages. Unfortunately, MSDN does not offer much
        // by way of useful information, and so the resulting sequence is the reult of experiment
        // that seems to work in multiple cases.
        //
        // The problem seems to be that the SetConsoleXXX functions are somewhat circular and
        // fail depending on the state of the current console properties, i.e. you can't set
        // the buffer size until you set the screen size, but you can't change the screen size
        // until the buffer size is correct. This coupled with a precise ordering of calls
        // makes this procedure seem a little mystical :-P. Thanks to wowLinh for helping - Jx9

        // Change console visual size to a minimum so ScreenBuffer can shrink
        // below the actual visual size
        m_rectWindow = { 0, 0, 1, 1 };
        SetConsoleWindowInfo(m_hConsole, TRUE, &m_rectWindow);

        // Set the size of the screen buffer
        COORD coord = { (short)m_nScreenWidth, (short)m_nScreenHeight };
        if (!SetConsoleScreenBufferSize(m_hConsole, coord))
            Error(L"SetConsoleScreenBufferSize");

        // Assign screen buffer to the console
        if (!SetConsoleActiveScreenBuffer(m_hConsole))
            return Error(L"SetConsoleActiveScreenBuffer");

        // Set the font size now that the screen buffer has been assigned to the console
        CONSOLE_FONT_INFOEX cfi;
        cfi.cbSize = sizeof(cfi);
        cfi.nFont = 0;
        cfi.dwFontSize.X = fontw;
        cfi.dwFontSize.Y = fonth;
        cfi.FontFamily = FF_DONTCARE;
        cfi.FontWeight = FW_NORMAL;

    /*  DWORD version = GetVersion();
        DWORD major = (DWORD)(LOBYTE(LOWORD(version)));
        DWORD minor = (DWORD)(HIBYTE(LOWORD(version)));*/

        //if ((major > 6) || ((major == 6) && (minor >= 2) && (minor < 4)))
        //  wcscpy_s(cfi.FaceName, L"Raster"); // Windows 8 :(
        //else
        //  wcscpy_s(cfi.FaceName, L"Lucida Console"); // Everything else :P

        //wcscpy_s(cfi.FaceName, L"Liberation Mono");
        wcscpy_s(cfi.FaceName, L"Consolas");
        if (!SetCurrentConsoleFontEx(m_hConsole, false, &cfi))
            return Error(L"SetCurrentConsoleFontEx");

        // Get screen buffer info and check the maximum allowed window size. Return
        // error if exceeded, so user knows their dimensions/fontsize are too large
        CONSOLE_SCREEN_BUFFER_INFO csbi;
        if (!GetConsoleScreenBufferInfo(m_hConsole, &csbi))
            return Error(L"GetConsoleScreenBufferInfo");
        if (m_nScreenHeight > csbi.dwMaximumWindowSize.Y)
            return Error(L"Screen Height / Font Height Too Big");
        if (m_nScreenWidth > csbi.dwMaximumWindowSize.X)
            return Error(L"Screen Width / Font Width Too Big");

        // Set Physical Console Window Size
        m_rectWindow = { 0, 0, (short)m_nScreenWidth - 1, (short)m_nScreenHeight - 1 };
        if (!SetConsoleWindowInfo(m_hConsole, TRUE, &m_rectWindow))
            return Error(L"SetConsoleWindowInfo");

        // Set flags to allow mouse input
        if (!SetConsoleMode(m_hConsoleIn, ENABLE_EXTENDED_FLAGS | ENABLE_WINDOW_INPUT | ENABLE_MOUSE_INPUT))
            return Error(L"SetConsoleMode");

        // Allocate memory for screen buffer
        m_bufScreen = new CHAR_INFO[m_nScreenWidth*m_nScreenHeight];
        memset(m_bufScreen, 0, sizeof(CHAR_INFO) * m_nScreenWidth * m_nScreenHeight);

        SetConsoleCtrlHandler((PHANDLER_ROUTINE)CloseHandler, TRUE);
        return 1;
    }

    virtual void Draw(int x, int y, short c = 0x2588, short col = 0x000F)
    {
        if (x >= 0 && x < m_nScreenWidth && y >= 0 && y < m_nScreenHeight)
        {
            m_bufScreen[y * m_nScreenWidth + x].Char.UnicodeChar = c;
            m_bufScreen[y * m_nScreenWidth + x].Attributes = col;
        }
    }

    void Fill(int x1, int y1, int x2, int y2, short c = 0x2588, short col = 0x000F)
    {
        Clip(x1, y1);
        Clip(x2, y2);
        for (int x = x1; x < x2; x++)
            for (int y = y1; y < y2; y++)
                Draw(x, y, c, col);
    }

    void DrawString(int x, int y, std::wstring c, short col = 0x000F)
    {
        for (size_t i = 0; i < c.size(); i++)
        {
            m_bufScreen[y * m_nScreenWidth + x + i].Char.UnicodeChar = c[i];
            m_bufScreen[y * m_nScreenWidth + x + i].Attributes = col;
        }
    }

    void DrawStringAlpha(int x, int y, std::wstring c, short col = 0x000F)
    {
        for (size_t i = 0; i < c.size(); i++)
        {
            if (c[i] != L' ')
            {
                m_bufScreen[y * m_nScreenWidth + x + i].Char.UnicodeChar = c[i];
                m_bufScreen[y * m_nScreenWidth + x + i].Attributes = col;
            }
        }
    }

    void Clip(int &x, int &y)
    {
        if (x < 0) x = 0;
        if (x >= m_nScreenWidth) x = m_nScreenWidth;
        if (y < 0) y = 0;
        if (y >= m_nScreenHeight) y = m_nScreenHeight;
    }

    void DrawLine(int x1, int y1, int x2, int y2, short c = 0x2588, short col = 0x000F)
    {
        int x, y, dx, dy, dx1, dy1, px, py, xe, ye, i;
        dx = x2 - x1; dy = y2 - y1;
        dx1 = abs(dx); dy1 = abs(dy);
        px = 2 * dy1 - dx1; py = 2 * dx1 - dy1;
        if (dy1 <= dx1)
        {
            if (dx >= 0)
                { x = x1; y = y1; xe = x2; }
            else
                { x = x2; y = y2; xe = x1;}

            Draw(x, y, c, col);

            for (i = 0; x<xe; i++)
            {
                x = x + 1;
                if (px<0)
                    px = px + 2 * dy1;
                else
                {
                    if ((dx<0 && dy<0) || (dx>0 && dy>0)) y = y + 1; else y = y - 1;
                    px = px + 2 * (dy1 - dx1);
                }
                Draw(x, y, c, col);
            }
        }
        else
        {
            if (dy >= 0)
                { x = x1; y = y1; ye = y2; }
            else
                { x = x2; y = y2; ye = y1; }

            Draw(x, y, c, col);

            for (i = 0; y<ye; i++)
            {
                y = y + 1;
                if (py <= 0)
                    py = py + 2 * dx1;
                else
                {
                    if ((dx<0 && dy<0) || (dx>0 && dy>0)) x = x + 1; else x = x - 1;
                    py = py + 2 * (dx1 - dy1);
                }
                Draw(x, y, c, col);
            }
        }
    }

    void DrawTriangle(int x1, int y1, int x2, int y2, int x3, int y3, short c = 0x2588, short col = 0x000F)
    {
        DrawLine(x1, y1, x2, y2, c, col);
        DrawLine(x2, y2, x3, y3, c, col);
        DrawLine(x3, y3, x1, y1, c, col);
    }

    // https://www.avrfreaks.net/sites/default/files/triangles.c
    void FillTriangle(int x1, int y1, int x2, int y2, int x3, int y3, short c = 0x2588, short col = 0x000F)
    {
        auto SWAP = [](int &x, int &y) { int t = x; x = y; y = t; };
        auto drawline = [&](int sx, int ex, int ny) { for (int i = sx; i <= ex; i++) Draw(i, ny, c, col); };

        int t1x, t2x, y, minx, maxx, t1xp, t2xp;
        bool changed1 = false;
        bool changed2 = false;
        int signx1, signx2, dx1, dy1, dx2, dy2;
        int e1, e2;
        // Sort vertices
        if (y1>y2) { SWAP(y1, y2); SWAP(x1, x2); }
        if (y1>y3) { SWAP(y1, y3); SWAP(x1, x3); }
        if (y2>y3) { SWAP(y2, y3); SWAP(x2, x3); }

        t1x = t2x = x1; y = y1;   // Starting points
        dx1 = (int)(x2 - x1); if (dx1<0) { dx1 = -dx1; signx1 = -1; }
        else signx1 = 1;
        dy1 = (int)(y2 - y1);

        dx2 = (int)(x3 - x1); if (dx2<0) { dx2 = -dx2; signx2 = -1; }
        else signx2 = 1;
        dy2 = (int)(y3 - y1);

        if (dy1 > dx1) {   // swap values
            SWAP(dx1, dy1);
            changed1 = true;
        }
        if (dy2 > dx2) {   // swap values
            SWAP(dy2, dx2);
            changed2 = true;
        }

        e2 = (int)(dx2 >> 1);
        // Flat top, just process the second half
        if (y1 == y2) goto next;
        e1 = (int)(dx1 >> 1);

        for (int i = 0; i < dx1;) {
            t1xp = 0; t2xp = 0;
            if (t1x<t2x) { minx = t1x; maxx = t2x; }
            else { minx = t2x; maxx = t1x; }
            // process first line until y value is about to change
            while (i<dx1) {
                i++;
                e1 += dy1;
                while (e1 >= dx1) {
                    e1 -= dx1;
                    if (changed1) t1xp = signx1;//t1x += signx1;
                    else          goto next1;
                }
                if (changed1) break;
                else t1x += signx1;
            }
            // Move line
        next1:
            // process second line until y value is about to change
            while (1) {
                e2 += dy2;
                while (e2 >= dx2) {
                    e2 -= dx2;
                    if (changed2) t2xp = signx2;//t2x += signx2;
                    else          goto next2;
                }
                if (changed2)     break;
                else              t2x += signx2;
            }
        next2:
            if (minx>t1x) minx = t1x; if (minx>t2x) minx = t2x;
            if (maxx<t1x) maxx = t1x; if (maxx<t2x) maxx = t2x;
            drawline(minx, maxx, y);    // Draw line from min to max points found on the y
                                         // Now increase y
            if (!changed1) t1x += signx1;
            t1x += t1xp;
            if (!changed2) t2x += signx2;
            t2x += t2xp;
            y += 1;
            if (y == y2) break;

        }
    next:
        // Second half
        dx1 = (int)(x3 - x2); if (dx1<0) { dx1 = -dx1; signx1 = -1; }
        else signx1 = 1;
        dy1 = (int)(y3 - y2);
        t1x = x2;

        if (dy1 > dx1) {   // swap values
            SWAP(dy1, dx1);
            changed1 = true;
        }
        else changed1 = false;

        e1 = (int)(dx1 >> 1);

        for (int i = 0; i <= dx1; i++) {
            t1xp = 0; t2xp = 0;
            if (t1x<t2x) { minx = t1x; maxx = t2x; }
            else { minx = t2x; maxx = t1x; }
            // process first line until y value is about to change
            while (i<dx1) {
                e1 += dy1;
                while (e1 >= dx1) {
                    e1 -= dx1;
                    if (changed1) { t1xp = signx1; break; }//t1x += signx1;
                    else          goto next3;
                }
                if (changed1) break;
                else          t1x += signx1;
                if (i<dx1) i++;
            }
        next3:
            // process second line until y value is about to change
            while (t2x != x3) {
                e2 += dy2;
                while (e2 >= dx2) {
                    e2 -= dx2;
                    if (changed2) t2xp = signx2;
                    else          goto next4;
                }
                if (changed2)     break;
                else              t2x += signx2;
            }
        next4:

            if (minx>t1x) minx = t1x; if (minx>t2x) minx = t2x;
            if (maxx<t1x) maxx = t1x; if (maxx<t2x) maxx = t2x;
            drawline(minx, maxx, y);
            if (!changed1) t1x += signx1;
            t1x += t1xp;
            if (!changed2) t2x += signx2;
            t2x += t2xp;
            y += 1;
            if (y>y3) return;
        }
    }

    void DrawCircle(int xc, int yc, int r, short c = 0x2588, short col = 0x000F)
    {
        int x = 0;
        int y = r;
        int p = 3 - 2 * r;
        if (!r) return;

        while (y >= x) // only formulate 1/8 of circle
        {
            Draw(xc - x, yc - y, c, col);//upper left left
            Draw(xc - y, yc - x, c, col);//upper upper left
            Draw(xc + y, yc - x, c, col);//upper upper right
            Draw(xc + x, yc - y, c, col);//upper right right
            Draw(xc - x, yc + y, c, col);//lower left left
            Draw(xc - y, yc + x, c, col);//lower lower left
            Draw(xc + y, yc + x, c, col);//lower lower right
            Draw(xc + x, yc + y, c, col);//lower right right
            if (p < 0) p += 4 * x++ + 6;
            else p += 4 * (x++ - y--) + 10;
        }
    }

    void FillCircle(int xc, int yc, int r, short c = 0x2588, short col = 0x000F)
    {
        // Taken from wikipedia
        int x = 0;
        int y = r;
        int p = 3 - 2 * r;
        if (!r) return;

        auto drawline = [&](int sx, int ex, int ny)
        {
            for (int i = sx; i <= ex; i++)
                Draw(i, ny, c, col);
        };

        while (y >= x)
        {
            // Modified to draw scan-lines instead of edges
            drawline(xc - x, xc + x, yc - y);
            drawline(xc - y, xc + y, yc - x);
            drawline(xc - x, xc + x, yc + y);
            drawline(xc - y, xc + y, yc + x);
            if (p < 0) p += 4 * x++ + 6;
            else p += 4 * (x++ - y--) + 10;
        }
    };

    void DrawSprite(int x, int y, olcSprite *sprite)
    {
        if (sprite == nullptr)
            return;

        for (int i = 0; i < sprite->nWidth; i++)
        {
            for (int j = 0; j < sprite->nHeight; j++)
            {
                if (sprite->GetGlyph(i, j) != L' ')
                    Draw(x + i, y + j, sprite->GetGlyph(i, j), sprite->GetColour(i, j));
            }
        }
    }

    void DrawPartialSprite(int x, int y, olcSprite *sprite, int ox, int oy, int w, int h)
    {
        if (sprite == nullptr)
            return;

        for (int i = 0; i < w; i++)
        {
            for (int j = 0; j < h; j++)
            {
                if (sprite->GetGlyph(i+ox, j+oy) != L' ')
                    Draw(x + i, y + j, sprite->GetGlyph(i+ox, j+oy), sprite->GetColour(i+ox, j+oy));
            }
        }
    }

    void DrawWireFrameModel(const std::vector<std::pair<float, float>> &vecModelCoordinates, float x, float y, float r = 0.0f, float s = 1.0f, short col = FG_WHITE, short c = PIXEL_SOLID)
    {
        // pair.first = x coordinate
        // pair.second = y coordinate

        // Create translated model vector of coordinate pairs
        std::vector<std::pair<float, float>> vecTransformedCoordinates;
        int verts = vecModelCoordinates.size();
        vecTransformedCoordinates.resize(verts);

        // Rotate
        for (int i = 0; i < verts; i++)
        {
            vecTransformedCoordinates[i].first = vecModelCoordinates[i].first * cosf(r) - vecModelCoordinates[i].second * sinf(r);
            vecTransformedCoordinates[i].second = vecModelCoordinates[i].first * sinf(r) + vecModelCoordinates[i].second * cosf(r);
        }

        // Scale
        for (int i = 0; i < verts; i++)
        {
            vecTransformedCoordinates[i].first = vecTransformedCoordinates[i].first * s;
            vecTransformedCoordinates[i].second = vecTransformedCoordinates[i].second * s;
        }

        // Translate
        for (int i = 0; i < verts; i++)
        {
            vecTransformedCoordinates[i].first = vecTransformedCoordinates[i].first + x;
            vecTransformedCoordinates[i].second = vecTransformedCoordinates[i].second + y;
        }

        // Draw Closed Polygon
        for (int i = 0; i < verts + 1; i++)
        {
            int j = (i + 1);
            DrawLine((int)vecTransformedCoordinates[i % verts].first, (int)vecTransformedCoordinates[i % verts].second,
                (int)vecTransformedCoordinates[j % verts].first, (int)vecTransformedCoordinates[j % verts].second, c, col);
        }
    }

    ~olcConsoleGameEngine()
    {
        SetConsoleActiveScreenBuffer(m_hOriginalConsole);
        delete[] m_bufScreen;
    }

public:
    void Start()
    {
        // Start the thread
        m_bAtomActive = true;
        std::thread t = std::thread(&olcConsoleGameEngine::GameThread, this);

        // Wait for thread to be exited
        t.join();
    }

    int ScreenWidth()
    {
        return m_nScreenWidth;
    }

    int ScreenHeight()
    {
        return m_nScreenHeight;
    }

private:
    void GameThread()
    {
        // Create user resources as part of this thread
        if (!OnUserCreate())
            m_bAtomActive = false;

        // Check if sound system should be enabled
        if (m_bEnableSound)
        {
            if (!CreateAudio())
            {
                m_bAtomActive = false; // Failed to create audio system
                m_bEnableSound = false;
            }
        }

        auto tp1 = std::chrono::system_clock::now();
        auto tp2 = std::chrono::system_clock::now();

        while (m_bAtomActive)
        {
            // Run as fast as possible
            while (m_bAtomActive)
            {
                // Handle Timing
                tp2 = std::chrono::system_clock::now();
                std::chrono::duration<float> elapsedTime = tp2 - tp1;
                tp1 = tp2;
                float fElapsedTime = elapsedTime.count();

                // Handle Keyboard Input
                for (int i = 0; i < 256; i++)
                {
                    m_keyNewState[i] = GetAsyncKeyState(i);

                    m_keys[i].bPressed = false;
                    m_keys[i].bReleased = false;

                    if (m_keyNewState[i] != m_keyOldState[i])
                    {
                        if (m_keyNewState[i] & 0x8000)
                        {
                            m_keys[i].bPressed = !m_keys[i].bHeld;
                            m_keys[i].bHeld = true;
                        }
                        else
                        {
                            m_keys[i].bReleased = true;
                            m_keys[i].bHeld = false;
                        }
                    }

                    m_keyOldState[i] = m_keyNewState[i];
                }

                // Handle Mouse Input - Check for window events
                INPUT_RECORD inBuf[32];
                DWORD events = 0;
                GetNumberOfConsoleInputEvents(m_hConsoleIn, &events);
                if (events > 0)
                    ReadConsoleInput(m_hConsoleIn, inBuf, events, &events);

                // Handle events - we only care about mouse clicks and movement
                // for now
                for (DWORD i = 0; i < events; i++)
                {
                    switch (inBuf[i].EventType)
                    {
                    case FOCUS_EVENT:
                    {
                        m_bConsoleInFocus = inBuf[i].Event.FocusEvent.bSetFocus;
                    }
                    break;

                    case MOUSE_EVENT:
                    {
                        switch (inBuf[i].Event.MouseEvent.dwEventFlags)
                        {
                        case MOUSE_MOVED:
                        {
                            m_mousePosX = inBuf[i].Event.MouseEvent.dwMousePosition.X;
                            m_mousePosY = inBuf[i].Event.MouseEvent.dwMousePosition.Y;
                        }
                        break;

                        case 0:
                        {
                            for (int m = 0; m < 5; m++)
                                m_mouseNewState[m] = (inBuf[i].Event.MouseEvent.dwButtonState & (1 << m)) > 0;

                        }
                        break;

                        default:
                            break;
                        }
                    }
                    break;

                    default:
                        break;
                        // We don't care just at the moment
                    }
                }

                for (int m = 0; m < 5; m++)
                {
                    m_mouse[m].bPressed = false;
                    m_mouse[m].bReleased = false;

                    if (m_mouseNewState[m] != m_mouseOldState[m])
                    {
                        if (m_mouseNewState[m])
                        {
                            m_mouse[m].bPressed = true;
                            m_mouse[m].bHeld = true;
                        }
                        else
                        {
                            m_mouse[m].bReleased = true;
                            m_mouse[m].bHeld = false;
                        }
                    }

                    m_mouseOldState[m] = m_mouseNewState[m];
                }


                // Handle Frame Update
                if (!OnUserUpdate(fElapsedTime))
                    m_bAtomActive = false;

                // Update Title & Present Screen Buffer
                wchar_t s[256];
                swprintf_s(s, 256, L"OneLoneCoder.com - Console Game Engine - %s - FPS: %3.2f", m_sAppName.c_str(), 1.0f / fElapsedTime);
                SetConsoleTitle(s);
                WriteConsoleOutput(m_hConsole, m_bufScreen, { (short)m_nScreenWidth, (short)m_nScreenHeight }, { 0,0 }, &m_rectWindow);
            }

            if (m_bEnableSound)
            {
                // Close and Clean up audio system
            }

            // Allow the user to free resources if they have overrided the destroy function
            if (OnUserDestroy())
            {
                // User has permitted destroy, so exit and clean up
                delete[] m_bufScreen;
                SetConsoleActiveScreenBuffer(m_hOriginalConsole);
                m_cvGameFinished.notify_one();
            }
            else
            {
                // User denied destroy for some reason, so continue running
                m_bAtomActive = true;
            }
        }
    }

public:
    // User MUST OVERRIDE THESE!!
    virtual bool OnUserCreate()                         = 0;
    virtual bool OnUserUpdate(float fElapsedTime)       = 0;

    // Optional for clean up
    virtual bool OnUserDestroy()                        { return true; }



protected: // Audio Engine =====================================================================

    class olcAudioSample
    {
    public:
        olcAudioSample()
        {

        }

        olcAudioSample(std::wstring sWavFile)
        {
            // Load Wav file and convert to float format
            FILE *f = nullptr;
            _wfopen_s(&f, sWavFile.c_str(), L"rb");
            if (f == nullptr)
                return;

            char dump[4];
            std::fread(&dump, sizeof(char), 4, f); // Read "RIFF"
            if (strncmp(dump, "RIFF", 4) != 0) return;
            std::fread(&dump, sizeof(char), 4, f); // Not Interested
            std::fread(&dump, sizeof(char), 4, f); // Read "WAVE"
            if (strncmp(dump, "WAVE", 4) != 0) return;

            // Read Wave description chunk
            std::fread(&dump, sizeof(char), 4, f); // Read "fmt "
            std::fread(&dump, sizeof(char), 4, f); // Not Interested
            std::fread(&wavHeader, sizeof(WAVEFORMATEX) - 2, 1, f); // Read Wave Format Structure chunk
                                                                    // Note the -2, because the structure has 2 bytes to indicate its own size
                                                                    // which are not in the wav file

            // Just check if wave format is compatible with olcCGE
            if (wavHeader.wBitsPerSample != 16 || wavHeader.nSamplesPerSec != 44100)
            {
                std::fclose(f);
                return;
            }

            // Search for audio data chunk
            long nChunksize = 0;
            std::fread(&dump, sizeof(char), 4, f); // Read chunk header
            std::fread(&nChunksize, sizeof(long), 1, f); // Read chunk size
            while (strncmp(dump, "data", 4) != 0)
            {
                // Not audio data, so just skip it
                std::fseek(f, nChunksize, SEEK_CUR);
                std::fread(&dump, sizeof(char), 4, f);
                std::fread(&nChunksize, sizeof(long), 1, f);
            }

            // Finally got to data, so read it all in and convert to float samples
            nSamples = nChunksize / (wavHeader.nChannels * (wavHeader.wBitsPerSample >> 3));
            nChannels = wavHeader.nChannels;

            // Create floating point buffer to hold audio sample
            fSample = new float[nSamples * nChannels];
            float *pSample = fSample;

            // Read in audio data and normalise
            for (long i = 0; i < nSamples; i++)
            {
                for (int c = 0; c < nChannels; c++)
                {
                    short s = 0;
                    std::fread(&s, sizeof(short), 1, f);
                    *pSample = (float)s / (float)(MAXSHORT);
                    pSample++;
                }
            }

            // All done, flag sound as valid
            std::fclose(f);
            bSampleValid = true;
        }

        WAVEFORMATEX wavHeader;
        float *fSample = nullptr;
        long nSamples = 0;
        int nChannels = 0;
        bool bSampleValid = false;
    };

    // This vector holds all loaded sound samples in memory
    std::vector<olcAudioSample> vecAudioSamples;

    // This structure represents a sound that is currently playing. It only
    // holds the sound ID and where this instance of it is up to for its
    // current playback
    struct sCurrentlyPlayingSample
    {
        int nAudioSampleID = 0;
        long nSamplePosition = 0;
        bool bFinished = false;
        bool bLoop = false;
    };
    std::list<sCurrentlyPlayingSample> listActiveSamples;

    // Load a 16-bit WAVE file @ 44100Hz ONLY into memory. A sample ID
    // number is returned if successful, otherwise -1
    unsigned int LoadAudioSample(std::wstring sWavFile)
    {
        if (!m_bEnableSound)
            return -1;

        olcAudioSample a(sWavFile);
        if (a.bSampleValid)
        {
            vecAudioSamples.push_back(a);
            return vecAudioSamples.size();
        }
        else
            return -1;
    }

    // Add sample 'id' to the mixers sounds to play list
    void PlaySample(int id, bool bLoop = false)
    {
        sCurrentlyPlayingSample a;
        a.nAudioSampleID = id;
        a.nSamplePosition = 0;
        a.bFinished = false;
        a.bLoop = bLoop;
        listActiveSamples.push_back(a);
    }

    void StopSample(int id)
    {

    }

    // The audio system uses by default a specific wave format
    bool CreateAudio(unsigned int nSampleRate = 44100, unsigned int nChannels = 1,
        unsigned int nBlocks = 8, unsigned int nBlockSamples = 512)
    {
        // Initialise Sound Engine
        m_bAudioThreadActive = false;
        m_nSampleRate = nSampleRate;
        m_nChannels = nChannels;
        m_nBlockCount = nBlocks;
        m_nBlockSamples = nBlockSamples;
        m_nBlockFree = m_nBlockCount;
        m_nBlockCurrent = 0;
        m_pBlockMemory = nullptr;
        m_pWaveHeaders = nullptr;

        // Device is available
        WAVEFORMATEX waveFormat;
        waveFormat.wFormatTag = WAVE_FORMAT_PCM;
        waveFormat.nSamplesPerSec = m_nSampleRate;
        waveFormat.wBitsPerSample = sizeof(short) * 8;
        waveFormat.nChannels = m_nChannels;
        waveFormat.nBlockAlign = (waveFormat.wBitsPerSample / 8) * waveFormat.nChannels;
        waveFormat.nAvgBytesPerSec = waveFormat.nSamplesPerSec * waveFormat.nBlockAlign;
        waveFormat.cbSize = 0;

        // Open Device if valid
        if (waveOutOpen(&m_hwDevice, WAVE_MAPPER, &waveFormat, (DWORD_PTR)waveOutProcWrap, (DWORD_PTR)this, CALLBACK_FUNCTION) != S_OK)
            return DestroyAudio();

        // Allocate Wave|Block Memory
        m_pBlockMemory = new short[m_nBlockCount * m_nBlockSamples];
        if (m_pBlockMemory == nullptr)
            return DestroyAudio();
        ZeroMemory(m_pBlockMemory, sizeof(short) * m_nBlockCount * m_nBlockSamples);

        m_pWaveHeaders = new WAVEHDR[m_nBlockCount];
        if (m_pWaveHeaders == nullptr)
            return DestroyAudio();
        ZeroMemory(m_pWaveHeaders, sizeof(WAVEHDR) * m_nBlockCount);

        // Link headers to block memory
        for (unsigned int n = 0; n < m_nBlockCount; n++)
        {
            m_pWaveHeaders[n].dwBufferLength = m_nBlockSamples * sizeof(short);
            m_pWaveHeaders[n].lpData = (LPSTR)(m_pBlockMemory + (n * m_nBlockSamples));
        }

        m_bAudioThreadActive = true;
        m_AudioThread = std::thread(&olcConsoleGameEngine::AudioThread, this);

        // Start the ball rolling with the sound delivery thread
        std::unique_lock<std::mutex> lm(m_muxBlockNotZero);
        m_cvBlockNotZero.notify_one();
        return true;
    }

    // Stop and clean up audio system
    bool DestroyAudio()
    {
        m_bAudioThreadActive = false;
        return false;
    }

    // Handler for soundcard request for more data
    void waveOutProc(HWAVEOUT hWaveOut, UINT uMsg, DWORD dwParam1, DWORD dwParam2)
    {
        if (uMsg != WOM_DONE) return;
        m_nBlockFree++;
        std::unique_lock<std::mutex> lm(m_muxBlockNotZero);
        m_cvBlockNotZero.notify_one();
    }

    // Static wrapper for sound card handler
    static void CALLBACK waveOutProcWrap(HWAVEOUT hWaveOut, UINT uMsg, DWORD dwInstance, DWORD dwParam1, DWORD dwParam2)
    {
        ((olcConsoleGameEngine*)dwInstance)->waveOutProc(hWaveOut, uMsg, dwParam1, dwParam2);
    }

    // Audio thread. This loop responds to requests from the soundcard to fill 'blocks'
    // with audio data. If no requests are available it goes dormant until the sound
    // card is ready for more data. The block is fille by the "user" in some manner
    // and then issued to the soundcard.
    void AudioThread()
    {
        m_fGlobalTime = 0.0f;
        float fTimeStep = 1.0f / (float)m_nSampleRate;

        // Goofy hack to get maximum integer for a type at run-time
        short nMaxSample = (short)pow(2, (sizeof(short) * 8) - 1) - 1;
        float fMaxSample = (float)nMaxSample;
        short nPreviousSample = 0;

        while (m_bAudioThreadActive)
        {
            // Wait for block to become available
            if (m_nBlockFree == 0)
            {
                std::unique_lock<std::mutex> lm(m_muxBlockNotZero);
                while (m_nBlockFree == 0) // sometimes, Windows signals incorrectly
                    m_cvBlockNotZero.wait(lm);
            }

            // Block is here, so use it
            m_nBlockFree--;

            // Prepare block for processing
            if (m_pWaveHeaders[m_nBlockCurrent].dwFlags & WHDR_PREPARED)
                waveOutUnprepareHeader(m_hwDevice, &m_pWaveHeaders[m_nBlockCurrent], sizeof(WAVEHDR));

            short nNewSample = 0;
            int nCurrentBlock = m_nBlockCurrent * m_nBlockSamples;

            auto clip = [](float fSample, float fMax)
            {
                if (fSample >= 0.0)
                    return fmin(fSample, fMax);
                else
                    return fmax(fSample, -fMax);
            };

            for (unsigned int n = 0; n < m_nBlockSamples; n += m_nChannels)
            {
                // User Process
                for (unsigned int c = 0; c < m_nChannels; c++)
                {
                    nNewSample = (short)(clip(GetMixerOutput(c, m_fGlobalTime, fTimeStep), 1.0) * fMaxSample);
                    m_pBlockMemory[nCurrentBlock + n + c] = nNewSample;
                    nPreviousSample = nNewSample;
                }

                m_fGlobalTime = m_fGlobalTime + fTimeStep;
            }

            // Send block to sound device
            waveOutPrepareHeader(m_hwDevice, &m_pWaveHeaders[m_nBlockCurrent], sizeof(WAVEHDR));
            waveOutWrite(m_hwDevice, &m_pWaveHeaders[m_nBlockCurrent], sizeof(WAVEHDR));
            m_nBlockCurrent++;
            m_nBlockCurrent %= m_nBlockCount;
        }
    }

    // Overridden by user if they want to generate sound in real-time
    virtual float onUserSoundSample(int nChannel, float fGlobalTime, float fTimeStep)
    {
        return 0.0f;
    }

    // Overriden by user if they want to manipulate the sound before it is played
    virtual float onUserSoundFilter(int nChannel, float fGlobalTime, float fSample)
    {
        return fSample;
    }

    // The Sound Mixer - If the user wants to play many sounds simultaneously, and
    // perhaps the same sound overlapping itself, then you need a mixer, which
    // takes input from all sound sources for that audio frame. This mixer maintains
    // a list of sound locations for all concurrently playing audio samples. Instead
    // of duplicating audio data, we simply store the fact that a sound sample is in
    // use and an offset into its sample data. As time progresses we update this offset
    // until it is beyound the length of the sound sample it is attached to. At this
    // point we remove the playing souind from the list.
    //
    // Additionally, the users application may want to generate sound instead of just
    // playing audio clips (think a synthesizer for example) in whcih case we also
    // provide an "onUser..." event to allow the user to return a sound for that point
    // in time.
    //
    // Finally, before the sound is issued to the operating system for performing, the
    // user gets one final chance to "filter" the sound, perhaps changing the volume
    // or adding funky effects
    float GetMixerOutput(int nChannel, float fGlobalTime, float fTimeStep)
    {
        // Accumulate sample for this channel
        float fMixerSample = 0.0f;

        for (auto &s : listActiveSamples)
        {
            // Calculate sample position
            s.nSamplePosition += (long)((float)vecAudioSamples[s.nAudioSampleID - 1].wavHeader.nSamplesPerSec * fTimeStep);

            // If sample position is valid add to the mix
            if (s.nSamplePosition < vecAudioSamples[s.nAudioSampleID - 1].nSamples)
                fMixerSample += vecAudioSamples[s.nAudioSampleID - 1].fSample[(s.nSamplePosition * vecAudioSamples[s.nAudioSampleID - 1].nChannels) + nChannel];
            else
                s.bFinished = true; // Else sound has completed
        }

        // If sounds have completed then remove them
        listActiveSamples.remove_if([](const sCurrentlyPlayingSample &s) {return s.bFinished; });

        // The users application might be generating sound, so grab that if it exists
        fMixerSample += onUserSoundSample(nChannel, fGlobalTime, fTimeStep);

        // Return the sample via an optional user override to filter the sound
        return onUserSoundFilter(nChannel, fGlobalTime, fMixerSample);
    }

    unsigned int m_nSampleRate;
    unsigned int m_nChannels;
    unsigned int m_nBlockCount;
    unsigned int m_nBlockSamples;
    unsigned int m_nBlockCurrent;

    short* m_pBlockMemory = nullptr;
    WAVEHDR *m_pWaveHeaders = nullptr;
    HWAVEOUT m_hwDevice = nullptr;

    std::thread m_AudioThread;
    std::atomic<bool> m_bAudioThreadActive = false;
    std::atomic<unsigned int> m_nBlockFree = 0;
    std::condition_variable m_cvBlockNotZero;
    std::mutex m_muxBlockNotZero;
    std::atomic<float> m_fGlobalTime = 0.0f;



protected:


    struct sKeyState
    {
        bool bPressed;
        bool bReleased;
        bool bHeld;
    } m_keys[256], m_mouse[5];

    int m_mousePosX;
    int m_mousePosY;

public:
    sKeyState GetKey(int nKeyID){ return m_keys[nKeyID]; }
    int GetMouseX() { return m_mousePosX; }
    int GetMouseY() { return m_mousePosY; }
    sKeyState GetMouse(int nMouseButtonID) { return m_mouse[nMouseButtonID]; }
    bool IsFocused() { return m_bConsoleInFocus; }


protected:
    int Error(const wchar_t *msg)
    {
        wchar_t buf[256];
        FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), buf, 256, NULL);
        SetConsoleActiveScreenBuffer(m_hOriginalConsole);
        wprintf(L"ERROR: %s\n\t%s\n", msg, buf);
        return 0;
    }

    static BOOL CloseHandler(DWORD evt)
    {
        // Note this gets called in a seperate OS thread, so it must
        // only exit when the game has finished cleaning up, or else
        // the process will be killed before OnUserDestroy() has finished
        if (evt == CTRL_CLOSE_EVENT)
        {
            m_bAtomActive = false;

            // Wait for thread to be exited
            std::unique_lock<std::mutex> ul(m_muxGame);
            m_cvGameFinished.wait(ul);
        }
        return true;
    }

protected:
    int m_nScreenWidth;
    int m_nScreenHeight;
    CHAR_INFO *m_bufScreen;
    std::wstring m_sAppName;
    HANDLE m_hOriginalConsole;
    CONSOLE_SCREEN_BUFFER_INFO m_OriginalConsoleInfo;
    HANDLE m_hConsole;
    HANDLE m_hConsoleIn;
    SMALL_RECT m_rectWindow;
    short m_keyOldState[256] = { 0 };
    short m_keyNewState[256] = { 0 };
    bool m_mouseOldState[5] = { 0 };
    bool m_mouseNewState[5] = { 0 };
    bool m_bConsoleInFocus = true;
    bool m_bEnableSound = false;

    // These need to be static because of the OnDestroy call the OS may make. The OS
    // spawns a special thread just for that
    static std::atomic<bool> m_bAtomActive;
    static std::condition_variable m_cvGameFinished;
    static std::mutex m_muxGame;
};

// Define our static variables
std::atomic<bool> olcConsoleGameEngine::m_bAtomActive(false);
std::condition_variable olcConsoleGameEngine::m_cvGameFinished;
std::mutex olcConsoleGameEngine::m_muxGame;