#include <windows.h>

#include "string.h"
#include "glmath.h"

#include <FreeImage.h> // http://freeimage.sourceforge.net/

#pragma comment(lib, "FreeImage.lib")

// ----------------------------------------------------------------------------------------------------------------------------

class CTexture
{
private:
    BYTE *Data;
    int Width, Height;

public:
    CTexture();
    ~CTexture();

    bool CreateTexture2D(char *Texture2DFileName);
    vec3 GetColorNearest(float s, float t);
    vec3 GetColorBilinear(float s, float t);
    void Destroy();
};

// ----------------------------------------------------------------------------------------------------------------------------

class CQuad
{
public:
    float Reflection, Refraction, Eta, ODEta, D, D1, D2, D3, D4;
    vec3 a, b, c, d, Color, ab, ad, m, T, B, N, O, N1, N2, N3, N4;
    CTexture *Texture;
    // static UINT Intersections;

public:
    CQuad();
    CQuad(const vec3 &a, const vec3 &b, const vec3 &c, const vec3 &d, const vec3 &Color, CTexture *Texture = NULL, float Reflection = 0.0f, float Refraction = 0.0f, float Eta = 1.0f);

    bool Inside(vec3 &Point);
    bool Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance, vec3 &Point);
    bool Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance);
    bool Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance);
};

// ----------------------------------------------------------------------------------------------------------------------------

class CSphere
{
public:
    float Radius, Radius2, ODRadius, Reflection, Refraction, Eta, ODEta;
    vec3 Position, Color;
    CTexture *Texture;
    // static UINT Intersections;

public:
    CSphere();
    CSphere(const vec3 &Position, float Radius, const vec3 &Color, CTexture *Texture = NULL, float Reflection = 0.0f, float Refraction = 0.0f, float Eta = 1.0f);

    bool Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance, vec3 &Point);
    bool Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance);
    bool Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance);
};

// ----------------------------------------------------------------------------------------------------------------------------

class CLight
{
public:
    float Ambient, Diffuse, ConstantAttenuation, LinearAttenuation, QuadraticAttenuation;
    CSphere *Sphere;
    CQuad *Quad;

public:
    CLight();
    ~CLight();
};

// ----------------------------------------------------------------------------------------------------------------------------

class CCamera
{
public:
    vec3 X, Y, Z, Reference, Position;
    mat4x4 Vin, Pin, Bin, VPin, RayMatrix;

public:
    CCamera();
    ~CCamera();

    void CalculateRayMatrix();
    void LookAt(const vec3 &Reference, const vec3 &Position, bool RotateAroundReference = false);
    bool OnKeyDown(UINT nChar);
    void OnMouseMove(int dx, int dy);
    void OnMouseWheel(short zDelta);
};

// ----------------------------------------------------------------------------------------------------------------------------

class RTData
{
public:
    float Distance, TestDistance;
    vec3 Color, Point, TestPoint;
    CQuad *Quad;
    CSphere *Sphere;
    CLight *Light;

public:
    RTData();
};

// ----------------------------------------------------------------------------------------------------------------------------

class CRayTracer
{
private:
    BYTE *ColorBuffer;
    BITMAPINFO ColorBufferInfo;
    vec3 *HDRColorBuffer;
    int Width, LineWidth, Height, Samples, GISamples, WidthMSamples, HeightMSamples, WidthMHeightMSamples2;
    float ODSamples2, ODGISamples, AmbientOcclusionIntensity, ODGISamplesMAmbientOcclusionIntensity;

protected:
    CQuad *Quads, *LastQuad;
    CSphere *Spheres, *LastSphere;
    CLight *Lights, *LastLight;
    int QuadsCount, SpheresCount, LightsCount;

public:
    bool Textures, SoftShadows, AmbientOcclusion;

public:
    CRayTracer();
    ~CRayTracer();

    bool Init();
    void RayTrace(int Line);
    void Resize(int Width, int Height);
    void Destroy();

    void ClearColorBuffer();
    int GetSamples();
    void MapHDRColors();
    bool SetSamples(int Samples);
    void SwapBuffers(HDC hDC);

protected:
    virtual bool InitScene() = 0;
    virtual void DestroyTextures() = 0;

private:
    bool Shadow(void *Object, vec3 &Point, vec3 &LightDirection, float LightDistance);
    vec3 LightIntensity(void *Object, vec3 &Point, vec3 &Normal, vec3 &LightPosition, CLight *Light, float AO);
    float AmbientOcclusionFactor(void *Object, vec3 &Point, vec3 &Normal);
    void IlluminatePoint(void *Object, vec3 &Point, vec3 &Normal, vec3 &Color);
    vec3 RayTrace(vec3 &Origin, const vec3 &Ray, UINT Depth = 0, void *Object = NULL);
};

// ----------------------------------------------------------------------------------------------------------------------------

class CMyRayTracer : public CRayTracer
{
private:
    CTexture Floor, Cube, Earth;

protected:
    bool InitScene();
    void DestroyTextures();
};

// ----------------------------------------------------------------------------------------------------------------------------

class CWnd
{
protected:
    char *WindowName;
    HWND hWnd;
    HDC hDC;
    int Width, Height, Line;
    POINT LastCurPos;

public:
    CWnd();
    ~CWnd();

    bool Create(HINSTANCE hInstance, char *WindowName, int Width, int Height);
    void RePaint();
    void Show(bool Maximized = false);
    void MsgLoop();
    void Destroy();

    void OnKeyDown(UINT Key);
    void OnMouseMove(int cx, int cy);
    void OnMouseWheel(short zDelta);
    void OnPaint();
    void OnRButtonDown(int cx, int cy);
    void OnSize(int Width, int Height);
};

// ----------------------------------------------------------------------------------------------------------------------------

LRESULT CALLBACK WndProc(HWND hWnd, UINT uiMsg, WPARAM wParam, LPARAM lParam);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR sCmdLine, int iShow);

#include "cpu_ray_tracer.h"

// ----------------------------------------------------------------------------------------------------------------------------

CString ModuleDirectory, ErrorLog;

// ----------------------------------------------------------------------------------------------------------------------------

CTexture::CTexture()
{
    Data = NULL;
    Width = Height = 0;
}

CTexture::~CTexture()
{
}

bool CTexture::CreateTexture2D(char *Texture2DFileName)
{
    CString FileName = ModuleDirectory + Texture2DFileName;
    CString ErrorText = "Error loading file " + FileName + "! -> ";

    FREE_IMAGE_FORMAT fif = FreeImage_GetFileType(FileName);

    if(fif == FIF_UNKNOWN)
    {
        fif = FreeImage_GetFIFFromFilename(FileName);
    }

    if(fif == FIF_UNKNOWN)
    {
        ErrorLog.Append(ErrorText + "fif is FIF_UNKNOWN" + "\r\n");
        return false;
    }

    FIBITMAP *dib = NULL;

    if(FreeImage_FIFSupportsReading(fif))
    {
        dib = FreeImage_Load(fif, FileName);
    }

    if(dib == NULL)
    {
        ErrorLog.Append(ErrorText + "dib is NULL" + "\r\n");
        return false;
    }

    int Width = FreeImage_GetWidth(dib);
    int Height = FreeImage_GetHeight(dib);
    int Pitch = FreeImage_GetPitch(dib);
    int BPP = FreeImage_GetBPP(dib);

    if(Width == 0 || Height == 0)
    {
        ErrorLog.Append(ErrorText + "Width or Height is 0" + "\r\n");
        return false;
    }

    BYTE *Bits = FreeImage_GetBits(dib);

    if(Bits == NULL)
    {
        ErrorLog.Append(ErrorText + "Bits is NULL" + "\r\n");
        return false;
    }

    if(BPP != 24 && BPP != 32)
    {
        FreeImage_Unload(dib);
        ErrorLog.Append(ErrorText + "BPP is not 24 nor 32" + "\r\n");
        return false;
    }

    Destroy();

    Data = new BYTE[Width * Height * 3];

    this->Width = Width;
    this->Height = Height;

    int bpp = BPP / 8;

    BYTE *data = Data, *line = Bits;

    for(int y = 0; y < Height; y++)
    {
        BYTE *pixel = line;

        for(int x = 0; x < Width; x++)
        {
            data[0] = pixel[2];
            data[1] = pixel[1];
            data[2] = pixel[0];

            pixel += bpp;
            data += 3;
        }

        line += Pitch;
    }

    FreeImage_Unload(dib);

    return true;
}

float OD255 = 1.0f / 255;

vec3 CTexture::GetColorNearest(float s, float t)
{
    vec3 Color = vec3(1.0f);

    if(Data != NULL)
    {
        s -= (int)s;
        t -= (int)t;
        
        if(s < 0.0f) s += 1.0f;
        if(t < 0.0f) t += 1.0f;

        int x = (int)(s * Width), y = (int)(t * Height);

        BYTE *data = (Width * y + x) * 3 + Data;

        Color.r = OD255 * data[0];
        Color.g = OD255 * data[1];
        Color.b = OD255 * data[2];
    }

    return Color;
}

vec3 CTexture::GetColorBilinear(float s, float t)
{
    vec3 Color = vec3(1.0f);

    if(Data != NULL)
    {
        s -= (int)s;
        t -= (int)t;
        
        if(s < 0.0f) s += 1.0f;
        if(t < 0.0f) t += 1.0f;

        float dx = s * Width - 0.5f, dy = t * Height - 0.5f;

        if(dx < 0.0f) dx += Width;
        if(dy < 0.0f) dy += Height;

        int x0 = (int)dx, y0 = (int)dy, x1 = (x0 + 1) % Width, y1 = (y0 + 1) % Height;

        int Width3 = Width * 3;

        BYTE *y0w = y0 * Width3 + Data;
        BYTE *y1w = y1 * Width3 + Data;

        int x03 = x0 * 3, x13 = x1 * 3;

        BYTE *a = y0w + x03;
        BYTE *b = y0w + x13;
        BYTE *c = y1w + x13;
        BYTE *d = y1w + x03;

        float u1 = dx - x0, v1 = dy - y0, u0 = 1.0f - u1, v0 = 1.0f - v1;

        u0 *= OD255;
        u1 *= OD255;

        float u0v0 = u0 * v0, u1v0 = u1 * v0, u1v1 = u1 * v1, u0v1 = u0 * v1;

        Color.r = u0v0 * a[0] + u1v0 * b[0] + u1v1 * c[0] + u0v1 * d[0];
        Color.g = u0v0 * a[1] + u1v0 * b[1] + u1v1 * c[1] + u0v1 * d[1];
        Color.b = u0v0 * a[2] + u1v0 * b[2] + u1v1 * c[2] + u0v1 * d[2];
    }

    return Color;
}

void CTexture::Destroy()
{
    if(Data != NULL)
    {
        delete [] Data;
        Data = NULL;
        Width = Height = 0;
    }
}

// ----------------------------------------------------------------------------------------------------------------------------

// UINT CQuad::Intersections;

CQuad::CQuad()
{
}

CQuad::CQuad(const vec3 &a, const vec3 &b, const vec3 &c, const vec3 &d, const vec3 &Color, CTexture *Texture, float Reflection, float Refraction, float Eta) : a(a), b(b), c(c), d(d), N(N), D(D), Color(Color), Texture(Texture), Reflection(Reflection), Refraction(Refraction), Eta(Eta)
{
    ab = b - a;
    ad = d - a;
    m = (a + b + c + d) / 4.0f;

    T = normalize(b - a);
    N = normalize(cross(b - a, c - a));
    B = cross(N, T);
    O = vec3(dot(T, a), dot(B, a), dot(N, a));

    D = -dot(N, a);
    ODEta = 1.0f / Eta;

    N1 = normalize(cross(N, b - a));
    D1 = -dot(N1, a);

    N2 = normalize(cross(N, c - b));
    D2 = -dot(N2, b);

    N3 = normalize(cross(N, d - c));
    D3 = -dot(N3, c);

    N4 = normalize(cross(N, a - d));
    D4 = -dot(N4, d);
}

bool CQuad::Inside(vec3 &Point)
{
    if(dot(N1, Point) + D1 < 0.0f) return false;
    if(dot(N2, Point) + D2 < 0.0f) return false;
    if(dot(N3, Point) + D3 < 0.0f) return false;
    if(dot(N4, Point) + D4 < 0.0f) return false;

    return true;
}

bool CQuad::Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance, vec3 &Point)
{
    // Intersections++;

    float NdotR = -dot(N, Ray);

    if(NdotR > 0.0f) // || (Refraction > 0.0f && NdotR < 0.0f))
    {
        Distance = (dot(N, Origin) + D) / NdotR;

        if(Distance >= 0.0f && Distance < MaxDistance)
        {
            Point = Ray * Distance + Origin;

            return Inside(Point);
        }
    }

    return false;
}

bool CQuad::Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance)
{
    // Intersections++;

    float NdotR = -dot(N, Ray);

    if(NdotR > 0.0f) // || (Refraction > 0.0f && NdotR < 0.0f))
    {
        Distance = (dot(N, Origin) + D) / NdotR;

        if(Distance >= 0.0f && Distance < MaxDistance)
        {
            return Inside(Ray * Distance + Origin);
        }
    }

    return false;
}

bool CQuad::Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance)
{
    // Intersections++;

    float NdotR = -dot(N, Ray);

    if(NdotR > 0.0f) // || (Refraction > 0.0f && NdotR < 0.0f))
    {
        float Distance = (dot(N, Origin) + D) / NdotR;

        if(Distance >= 0.0f && Distance < MaxDistance)
        {
            return Inside(Ray * Distance + Origin);
        }
    }

    return false;
}

// ----------------------------------------------------------------------------------------------------------------------------

// UINT CSphere::Intersections;

CSphere::CSphere()
{
}

CSphere::CSphere(const vec3 &Position, float Radius, const vec3 &Color, CTexture *Texture, float Reflection, float Refraction, float Eta) : Position(Position), Radius(Radius), Color(Color), Texture(Texture), Reflection(Reflection), Refraction(Refraction), Eta(Eta)
{
    Radius2 = Radius * Radius;
    ODRadius = 1.0f / Radius;
    ODEta = 1.0f / Eta;
}

bool CSphere::Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance, vec3 &Point)
{
    // Intersections++;

    vec3 L = Position - Origin;

    float LdotR = dot(L, Ray);

    if(LdotR > 0.0f)
    {
        float D2 = length2(L) - LdotR * LdotR;

        if(D2 < Radius2)
        {
            Distance = LdotR - sqrt(Radius2 - D2);

            if(Distance >= 0.0f && Distance < MaxDistance)
            {
                Point = Ray * Distance + Origin;

                return true;
            }
        }
    }

    return false;
}

bool CSphere::Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance, float &Distance)
{
    // Intersections++;

    vec3 L = Position - Origin;

    float LdotR = dot(L, Ray);

    if(LdotR > 0.0f)
    {
        float D2 = length2(L) - LdotR * LdotR;

        if(D2 < Radius2)
        {
            Distance = LdotR - sqrt(Radius2 - D2);

            if(Distance >= 0.0f && Distance < MaxDistance)
            {
                return true;
            }
        }
    }

    return false;
}

bool CSphere::Intersect(vec3 &Origin, const vec3 &Ray, float MaxDistance)
{
    // Intersections++;

    vec3 L = Position - Origin;

    float LdotR = dot(L, Ray);

    if(LdotR > 0.0f)
    {
        float D2 = length2(L) - LdotR * LdotR;

        if(D2 < Radius2)
        {
            float Distance = LdotR - sqrt(Radius2 - D2);

            if(Distance >= 0.0f && Distance < MaxDistance)
            {
                return true;
            }
        }
    }

    return false;
}

// ----------------------------------------------------------------------------------------------------------------------------

CLight::CLight()
{
    Ambient = 1.0f;
    Diffuse = 1.0f;

    ConstantAttenuation = 1.0f;
    LinearAttenuation = 0.0f;
    QuadraticAttenuation = 0.0f;

    Sphere = NULL;
    Quad = NULL;
}

CLight::~CLight()
{
    if(Sphere)
    {
        delete Sphere;
    }
    else
    {
        delete Quad;
    }
}

// ----------------------------------------------------------------------------------------------------------------------------

CCamera::CCamera()
{
    X = vec3(1.0, 0.0, 0.0);
    Y = vec3(0.0, 1.0, 0.0);
    Z = vec3(0.0, 0.0, 1.0);

    Reference = vec3(0.0, 0.0, 0.0);
    Position = vec3(0.0, 0.0, 5.0);

    Bin = BiasMatrixInverse();
}

CCamera::~CCamera()
{
}

void CCamera::CalculateRayMatrix()
{
    Vin[0] = X.x; Vin[4] = Y.x; Vin[8] = Z.x;
    Vin[1] = X.y; Vin[5] = Y.y; Vin[9] = Z.y;
    Vin[2] = X.z; Vin[6] = Y.z; Vin[10] = Z.z;

    RayMatrix = Vin * Pin * Bin * VPin;
}

void CCamera::LookAt(const vec3 &Reference, const vec3 &Position, bool RotateAroundReference)
{
    this->Reference = Reference;
    this->Position = Position;

    Z = normalize(Position - Reference);
    X = normalize(cross(vec3(0.0f, 1.0f, 0.0f), Z));
    Y = cross(Z, X);

    if(!RotateAroundReference)
    {
        this->Reference = this->Position;
        this->Position += Z * 0.05f;
    }

    CalculateRayMatrix();
}

bool CCamera::OnKeyDown(UINT nChar)
{
    float Distance = 0.125f;

    if(GetKeyState(VK_CONTROL) & 0x80)
    {
        Distance *= 0.5f;
    }

    if(GetKeyState(VK_SHIFT) & 0x80)
    {
        Distance *= 2.0f;
    }

    vec3 Up(0.0f, 1.0f, 0.0f);
    vec3 Right = X;
    vec3 Forward = cross(Up, Right);

    Up *= Distance;
    Right *= Distance;
    Forward *= Distance;

    vec3 Movement;

    if(nChar == 'W')
    {
        Movement += Forward;
    }

    if(nChar == 'S')
    {
        Movement -= Forward;
    }

    if(nChar == 'A')
    {
        Movement -= Right;
    }

    if(nChar == 'D')
    {
        Movement += Right;
    }

    if(nChar == 'R')
    {
        Movement += Up;
    }

    if(nChar == 'F')
    {
        Movement -= Up;
    }

    Reference += Movement;
    Position += Movement;

    return Movement.x != 0.0f || Movement.y != 0.0f || Movement.z != 0.0f;
}

void CCamera::OnMouseMove(int dx, int dy)
{
    float sensitivity = 0.25f;

    float hangle = (float)dx * sensitivity;
    float vangle = (float)dy * sensitivity;

    Position -= Reference;

    Y = rotate(Y, vangle, X);
    Z = rotate(Z, vangle, X);

    if(Y.y < 0.0f)
    {
        Z = vec3(0.0f, Z.y > 0.0f ? 1.0f : -1.0f, 0.0f);
        Y = cross(Z, X);
    }

    X = rotate(X, hangle, vec3(0.0f, 1.0f, 0.0f));
    Y = rotate(Y, hangle, vec3(0.0f, 1.0f, 0.0f));
    Z = rotate(Z, hangle, vec3(0.0f, 1.0f, 0.0f));

    Position = Reference + Z * length(Position);

    CalculateRayMatrix();
}

void CCamera::OnMouseWheel(short zDelta)
{
    Position -= Reference;

    if(zDelta < 0 && length(Position) < 500.0f)
    {
        Position += Position * 0.1f;
    }

    if(zDelta > 0 && length(Position) > 0.05f)
    {
        Position -= Position * 0.1f;
    }

    Position += Reference;
}

CCamera Camera;

// ----------------------------------------------------------------------------------------------------------------------------

RTData::RTData()
{
    Distance = 1048576.0f;

    Quad = NULL;
    Light = NULL;
    Sphere = NULL;
}

// ----------------------------------------------------------------------------------------------------------------------------

CRayTracer::CRayTracer()
{
    ColorBuffer = NULL;
    HDRColorBuffer = NULL;

    Samples = 1;
    GISamples = 16;
    
    ODGISamples = 1.0f / (float)GISamples;
    AmbientOcclusionIntensity = 0.5f;
    ODGISamplesMAmbientOcclusionIntensity = ODGISamples * AmbientOcclusionIntensity;

    Quads = NULL;
    Spheres = NULL;
    Lights = NULL;

    LastQuad = NULL;
    LastSphere = NULL;
    LastLight = NULL;

    QuadsCount = 0;
    SpheresCount = 0;
    LightsCount = 0;

    Textures = true;
    SoftShadows = false;
    AmbientOcclusion = false;

    srand(GetTickCount());
}

CRayTracer::~CRayTracer()
{
}

bool CRayTracer::Init()
{
    if(InitScene() == false)
    {
        return false;
    }

    LastQuad = Quads + QuadsCount;
    LastSphere = Spheres + SpheresCount;
    LastLight = Lights + LightsCount;

    return true;
}

void CRayTracer::RayTrace(int Line)
{
    if(ColorBuffer == NULL || HDRColorBuffer == NULL) return;

    vec3 *hdrcolorbuffer;
    BYTE *colorbuffer = LineWidth * Line * 3 + ColorBuffer;

    if(Samples == 1)
    {
        hdrcolorbuffer = Width * Line + HDRColorBuffer;

        for(int x = 0; x < Width; x++)
        {
            vec3 Color = RayTrace(Camera.Position, normalize(Camera.RayMatrix * vec3((float)x, (float)Line, 0.0f)));

            hdrcolorbuffer->r = Color.r;
            hdrcolorbuffer->g = Color.g;
            hdrcolorbuffer->b = Color.b;

            hdrcolorbuffer++;

            colorbuffer[2] = Color.r <= 0.0f ? 0 : Color.r >= 1.0 ? 255 : (BYTE)(Color.r * 255);
            colorbuffer[1] = Color.g <= 0.0f ? 0 : Color.g >= 1.0 ? 255 : (BYTE)(Color.g * 255);
            colorbuffer[0] = Color.b <= 0.0f ? 0 : Color.b >= 1.0 ? 255 : (BYTE)(Color.b * 255);

            colorbuffer += 3;
        }
    }
    else
    {
        int Y = Line * Samples;

        for(int X = 0; X < WidthMSamples; X += Samples)
        {
            vec3 SamplesSum;

            for(int yy = 0; yy < Samples; yy++)
            {
                int Yyy = Y + yy;

                hdrcolorbuffer = WidthMSamples * Yyy + X + HDRColorBuffer;

                for(int xx = 0; xx < Samples; xx++)
                {
                    vec3 Color = RayTrace(Camera.Position, normalize(Camera.RayMatrix * vec3((float)(X + xx), (float)Yyy, 0.0f)));

                    hdrcolorbuffer->r = Color.r;
                    hdrcolorbuffer->g = Color.g;
                    hdrcolorbuffer->b = Color.b;

                    hdrcolorbuffer++;

                    SamplesSum.r += Color.r <= 0.0f ? 0.0f : Color.r >= 1.0 ? 1.0f : Color.r;
                    SamplesSum.g += Color.g <= 0.0f ? 0.0f : Color.g >= 1.0 ? 1.0f : Color.g;
                    SamplesSum.b += Color.b <= 0.0f ? 0.0f : Color.b >= 1.0 ? 1.0f : Color.b;
                }
            }

            SamplesSum.r *= ODSamples2;
            SamplesSum.g *= ODSamples2;
            SamplesSum.b *= ODSamples2;

            colorbuffer[2] = (BYTE)(SamplesSum.r * 255);
            colorbuffer[1] = (BYTE)(SamplesSum.g * 255);
            colorbuffer[0] = (BYTE)(SamplesSum.b * 255);

            colorbuffer += 3;
        }
    }
}

void CRayTracer::Resize(int Width, int Height)
{
    this->Width = Width;
    this->Height = Height;

    if(ColorBuffer != NULL)
    {
        delete [] ColorBuffer;
        ColorBuffer = NULL;
    }

    if(HDRColorBuffer != NULL)
    {
        delete [] HDRColorBuffer;
        HDRColorBuffer = NULL;
    }

    if(Width > 0 && Height > 0)
    {
        LineWidth = Width;

        int WidthMod4 = Width % 4;

        if(WidthMod4 > 0)
        {
            LineWidth += 4 - WidthMod4;
        }

        ColorBuffer = new BYTE[LineWidth * Height * 3];

        memset(&ColorBufferInfo, 0, sizeof(BITMAPINFOHEADER));
        ColorBufferInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
        ColorBufferInfo.bmiHeader.biPlanes = 1;
        ColorBufferInfo.bmiHeader.biBitCount = 24;
        ColorBufferInfo.bmiHeader.biCompression = BI_RGB;
        ColorBufferInfo.bmiHeader.biWidth = LineWidth;
        ColorBufferInfo.bmiHeader.biHeight = Height;

        WidthMSamples = Width * Samples;
        HeightMSamples = Height * Samples;
        WidthMHeightMSamples2 = WidthMSamples * HeightMSamples;
        ODSamples2 = 1.0f / (float)(Samples * Samples);

        HDRColorBuffer = new vec3[WidthMHeightMSamples2];

        Camera.VPin[0] = 1.0f / (float)(WidthMSamples - 1);
        Camera.VPin[5] = 1.0f / (float)(HeightMSamples - 1);

        float tany = tan(45.0f / 360.0f * (float)M_PI), aspect = (float)Width / (float)Height;

        Camera.Pin[0] = tany * aspect;
        Camera.Pin[5] = tany;
        Camera.Pin[10] = 0.0f;
        Camera.Pin[14] = -1.0f;

        Camera.CalculateRayMatrix();
    }
}

void CRayTracer::Destroy()
{
    DestroyTextures();

    if(Quads != NULL)
    {
        delete [] Quads;
        Quads = NULL;
        QuadsCount = 0;
        LastQuad = NULL;
    }

    if(Spheres != NULL)
    {
        delete [] Spheres;
        Spheres = NULL;
        SpheresCount = 0;
        LastSphere = NULL;
    }

    if(Lights != NULL)
    {
        delete [] Lights;
        Lights = NULL;
        LightsCount = 0;
        LastLight = NULL;
    }

    if(ColorBuffer != NULL)
    {
        delete [] ColorBuffer;
        ColorBuffer = NULL;
    }

    if(HDRColorBuffer != NULL)
    {
        delete [] HDRColorBuffer;
        HDRColorBuffer = NULL;
    }
}

void CRayTracer::ClearColorBuffer()
{
    if(ColorBuffer != NULL)
    {
        memset(ColorBuffer, 0, LineWidth * Height * 3);
    }
}

int CRayTracer::GetSamples()
{
    return Samples * Samples;
}

void CRayTracer::MapHDRColors()
{
    if(ColorBuffer == NULL || HDRColorBuffer == NULL) return;

    float SumLum = 0.0f, LumWhite = 0.0f;
    int LumNotNull = 0;

    vec3 *Color = HDRColorBuffer;

    for(int i = 0; i < WidthMHeightMSamples2; i++)
    {
        float Luminance = (Color->r * 0.2125f + Color->g * 0.7154f + Color->b * 0.0721f);

        if(Luminance > 0.0f)
        {
            SumLum += Luminance;

            LumNotNull++;

            LumWhite = LumWhite > Luminance ? LumWhite : Luminance;
        }

        Color++;
    }

    float AvgLum = SumLum / (float)LumNotNull;

    LumWhite /= AvgLum;

    float LumWhite2 = LumWhite * LumWhite;

    Color = HDRColorBuffer;

    vec3 ColorMMappingFactor;

    for(int i = 0; i < WidthMHeightMSamples2; i++)
    {
        float Luminance = (Color->r * 0.2125f + Color->g * 0.7154f + Color->b * 0.0721f);
            
        float LumRel = Luminance / AvgLum;
        float MappingFactor = LumRel * (1.0f + LumRel / LumWhite2) / (1.0f + LumRel);

        ColorMMappingFactor.r = Color->r * MappingFactor;
        ColorMMappingFactor.g = Color->g * MappingFactor;
        ColorMMappingFactor.b = Color->b * MappingFactor;
        
        Color->r = ColorMMappingFactor.r <= 0.0f ? 0.0f : ColorMMappingFactor.r >= 1.0f ? 1.0f : ColorMMappingFactor.r;
        Color->g = ColorMMappingFactor.g <= 0.0f ? 0.0f : ColorMMappingFactor.g >= 1.0f ? 1.0f : ColorMMappingFactor.g;
        Color->b = ColorMMappingFactor.b <= 0.0f ? 0.0f : ColorMMappingFactor.b >= 1.0f ? 1.0f : ColorMMappingFactor.b;

        Color++;
    }

    int LineWidthSWidthM3 = (LineWidth - Width) * 3;

    BYTE *colorbuffer = ColorBuffer;

    if(Samples == 1)
    {
        Color = HDRColorBuffer;

        for(int y = 0; y < Height; y++)
        {
            for(int x = 0; x < Width; x++)
            {
                colorbuffer[2] = (BYTE)(Color->r * 255);
                colorbuffer[1] = (BYTE)(Color->g * 255);
                colorbuffer[0] = (BYTE)(Color->b * 255);

                Color++;
                colorbuffer += 3;
            }

            colorbuffer += LineWidthSWidthM3;
        }
    }
    else
    {
        for(int y = 0, Y = 0; y < Height; y++, Y += Samples)
        {
            for(int X = 0; X < WidthMSamples; X += Samples)
            {
                vec3 ColorSum;

                for(int yy = 0; yy < Samples; yy++)
                {
                    Color = WidthMSamples * (Y + yy) + X + HDRColorBuffer;

                    for(int xx = 0; xx < Samples; xx++)
                    {
                        ColorSum.r += Color->r;
                        ColorSum.g += Color->g;
                        ColorSum.b += Color->b;

                        Color++;
                    }
                }

                ColorSum.r *= ODSamples2;
                ColorSum.g *= ODSamples2;
                ColorSum.b *= ODSamples2;

                colorbuffer[2] = (BYTE)(ColorSum.r * 255);
                colorbuffer[1] = (BYTE)(ColorSum.g * 255);
                colorbuffer[0] = (BYTE)(ColorSum.b * 255);

                colorbuffer += 3;
            }

            colorbuffer += LineWidthSWidthM3;
        }
    }
}

bool CRayTracer::SetSamples(int Samples)
{
    if(this->Samples == Samples) return false;

    this->Samples = Samples;

    Resize(Width, Height);

    return true;
}

void CRayTracer::SwapBuffers(HDC hDC)
{
    if(ColorBuffer != NULL)
    {
        StretchDIBits(hDC, 0, 0, Width, Height, 0, 0, Width, Height, ColorBuffer, &ColorBufferInfo, DIB_RGB_COLORS, SRCCOPY);
    }
}

bool CRayTracer::Shadow(void *Object, vec3 &Point, vec3 &LightDirection, float LightDistance)
{
    for(CSphere *Sphere = Spheres; Sphere < LastSphere; Sphere++)
    {
        if(Sphere == Object) continue;

        if(Sphere->Intersect(Point, LightDirection, LightDistance))
        {
            return true;
        }
    }

    for(CQuad *Quad = Quads; Quad < LastQuad; Quad++)
    {
        if(Quad == Object) continue;

        if(Quad->Intersect(Point, LightDirection, LightDistance))
        {
            return true;
        }
    }

    return false;
}

vec3 CRayTracer::LightIntensity(void *Object, vec3 &Point, vec3 &Normal, vec3 &LightPosition, CLight *Light, float AO)
{
    vec3 LightDirection = LightPosition - Point;

    float LightDistance2 = length2(LightDirection);
    float LightDistance = sqrt(LightDistance2);

    LightDirection *= 1.0f / LightDistance;

    float Attenuation = Light->QuadraticAttenuation * LightDistance2 + Light->LinearAttenuation * LightDistance + Light->ConstantAttenuation;

    float NdotLD = dot(Normal, LightDirection);

    if(NdotLD > 0.0f)
    {
        if(Light->Sphere)
        {
            if(Shadow(Object, Point, LightDirection, LightDistance) == false)
            {
                return Light->Sphere->Color * ((Light->Ambient * AO + Light->Diffuse * NdotLD) / Attenuation);
            }
        }
        else
        {
            float LNdotLD = -dot(Light->Quad->N, LightDirection);

            if(LNdotLD > 0.0f)
            {
                if(Shadow(Object, Point, LightDirection, LightDistance) == false)
                {
                    return Light->Quad->Color * ((Light->Ambient * AO + Light->Diffuse * NdotLD * LNdotLD) / Attenuation);
                }
            }
        }
    }

    return (Light->Sphere ? Light->Sphere->Color : Light->Quad->Color) * (Light->Ambient * AO / Attenuation);
}

float TDRM = 2.0f / (float)RAND_MAX;

float CRayTracer::AmbientOcclusionFactor(void *Object, vec3 &Point, vec3 &Normal)
{
    float AO = 0.0f;

    for(int i = 0; i < GISamples; i++)
    {
        vec3 RandomRay = normalize(vec3(TDRM * (float)rand() - 1.0f, TDRM * (float)rand() - 1.0f, TDRM * (float)rand() - 1.0f));

        float NdotRR = dot(Normal, RandomRay);

        if(NdotRR < 0.0f)
        {
            RandomRay = -RandomRay;
            NdotRR = -NdotRR;
        }

        float Distance = 1048576.0f, TestDistance;

        for(CSphere *Sphere = Spheres; Sphere < LastSphere; Sphere++)
        {
            if(Sphere == Object) continue;

            if(Sphere->Intersect(Point, RandomRay, Distance, TestDistance))
            {
                Distance = TestDistance;
            }
        }

        for(CQuad *Quad = Quads; Quad < LastQuad; Quad++)
        {
            if(Quad == Object) continue;

            if(Quad->Intersect(Point, RandomRay, Distance, TestDistance))
            {
                Distance = TestDistance;
            }
        }

        AO += NdotRR / (1.0f + Distance * Distance);
    }

    return 1.0f - AO * ODGISamplesMAmbientOcclusionIntensity;
}

float ODRM = 1.0f / (float)RAND_MAX;

void CRayTracer::IlluminatePoint(void *Object, vec3 &Point, vec3 &Normal, vec3 &Color)
{
    float AO = 1.0f;

    if(AmbientOcclusion)
    {
        AO = AmbientOcclusionFactor(Object, Point, Normal);
    }

    if(LightsCount == 0)
    {
        float NdotCD = dot(Normal, normalize(Camera.Position - Point));

        if(NdotCD > 0.0f)
        {
            Color *= 0.5f * (AO + NdotCD);
        }
        else
        {
            Color *= 0.5f * AO;
        }
    }
    else if(SoftShadows == false)
    {
        vec3 LightsIntensitiesSum;

        for(CLight *Light = Lights; Light < LastLight; Light++)
        {
            LightsIntensitiesSum += LightIntensity(Object, Point, Normal, Light->Sphere ? Light->Sphere->Position : Light->Quad->m, Light, AO);
        }

        Color *= LightsIntensitiesSum;
    }
    else
    {
        vec3 LightsIntensitiesSum;

        for(CLight *Light = Lights; Light < LastLight; Light++)
        {
            if(Light->Sphere)
            {
                for(int i = 0; i < GISamples; i++)
                {
                    vec3 RandomRay = /*normalize(*/vec3(TDRM * (float)rand() - 1.0f, TDRM * (float)rand() - 1.0f, TDRM * (float)rand() - 1.0f)/*)*/;

                    vec3 RandomLightPosition = RandomRay * Light->Sphere->Radius + Light->Sphere->Position;

                    LightsIntensitiesSum += LightIntensity(Object, Point, Normal, RandomLightPosition, Light, AO);
                }
            }
            else
            {
                for(int i = 0; i < GISamples; i++)
                {
                    float s = ODRM * (float)rand();
                    float t = ODRM * (float)rand();

                    vec3 RandomLightPosition = Light->Quad->ab * s + Light->Quad->ad * t + Light->Quad->a;

                    LightsIntensitiesSum += LightIntensity(Object, Point, Normal, RandomLightPosition, Light, AO);
                }
            }
        }

        Color *= LightsIntensitiesSum * ODGISamples;
    }
}

float M_1_PI_2 = (float)M_1_PI * 0.5f;

vec3 CRayTracer::RayTrace(vec3 &Origin, const vec3 &Ray, UINT Depth, void *Object)
{
    RTData Data;

    for(CSphere *Sphere = Spheres; Sphere < LastSphere; Sphere++)
    {
        if(Sphere == Object) continue;

        if(Sphere->Intersect(Origin, Ray, Data.Distance, Data.TestDistance, Data.TestPoint))
        {
            Data.Point = Data.TestPoint;
            Data.Distance = Data.TestDistance;
            Data.Sphere = Sphere;
        }
    }

    for(CQuad *Quad = Quads; Quad < LastQuad; Quad++)
    {
        if(Quad == Object) continue;

        if(Quad->Intersect(Origin, Ray, Data.Distance, Data.TestDistance, Data.TestPoint))
        {
            Data.Point = Data.TestPoint;
            Data.Distance = Data.TestDistance;
            Data.Quad = Quad;
        }
    }

    for(CLight *Light = Lights; Light < LastLight; Light++)
    {
        if(Light->Sphere)
        {
            if(Light->Sphere->Intersect(Origin, Ray, Data.Distance, Data.TestDistance, Data.TestPoint))
            {
                Data.Point = Data.TestPoint;
                Data.Distance = Data.TestDistance;
                Data.Light = Light;
            }
        }
        else
        {
            if(Light->Quad->Intersect(Origin, Ray, Data.Distance, Data.TestDistance, Data.TestPoint))
            {
                Data.Point = Data.TestPoint;
                Data.Distance = Data.TestDistance;
                Data.Light = Light;
            }
        }
    }

    if(Data.Light)
    {
        Data.Color = Data.Light->Sphere ? Data.Light->Sphere->Color : Data.Light->Quad->Color;
    }
    else if(Data.Quad)
    {
        Data.Color = Data.Quad->Color;

        if(Textures && Data.Quad->Texture)
        {
            float s = dot(Data.Quad->T, Data.Point) - Data.Quad->O.x;
            float t = dot(Data.Quad->B, Data.Point) - Data.Quad->O.y;

            Data.Color *= Data.Quad->Texture->GetColorBilinear(s, t);
        }

        IlluminatePoint(Data.Quad, Data.Point, Data.Quad->N, Data.Color);
        
        if(Data.Quad->Reflection > 0.0f)
        {
            vec3 ReflectedRay = reflect(Ray, Data.Quad->N);

            Data.Color = mix(Data.Color, RayTrace(Data.Point, ReflectedRay, Depth + 1, Data.Quad), Data.Quad->Reflection);
        }

        /*if(Data.Quad->Refraction > 0.0f)
        {
            float Angle = -dot(Data.Quad->N, Ray);

            vec3 Normal;
            float Eta;
            
            if(Angle > 0.0f)
            {
                Normal = Data.Quad->N;
                Eta = Data.Quad->ODEta;
            }
            else
            {
                Normal = -Data.Quad->N;
                Eta = Data.Quad->Eta;
            }

            vec3 RefractedRay = refract(Ray, Normal, Eta);

            if(RefractedRay.x == 0.0f && RefractedRay.y == 0.0f && RefractedRay.z == 0.0f)
            {
                RefractedRay = reflect(Ray, Normal);
            }

            Data.Color = mix(Data.Color, RayTrace(Data.Point, RefractedRay, Depth + 1, Data.Quad), Data.Quad->Refraction);
        }*/
    }
    else if(Data.Sphere)
    {
        Data.Color = Data.Sphere->Color;

        vec3 Normal = (Data.Point - Data.Sphere->Position) * Data.Sphere->ODRadius;

        if(Textures && Data.Sphere->Texture)
        {
            float s = atan2(Normal.x, Normal.z) * M_1_PI_2 + 0.5f;
            float t = asin(Normal.y < -1.0f ? -1.0f : Normal.y > 1.0f ? 1.0f : Normal.y) * (float)M_1_PI + 0.5f;

            Data.Color *= Data.Sphere->Texture->GetColorBilinear(s, t);
        }

        IlluminatePoint(Data.Sphere, Data.Point, Normal, Data.Color);

        if(Data.Sphere->Refraction > 0.0f)
        {
            vec3 RefractedRay = refract(Ray, Normal, Data.Sphere->ODEta);

            vec3 L = Data.Sphere->Position - Data.Point;
            float LdotRR = dot(L, RefractedRay);
            float D2 = length2(L) - LdotRR * LdotRR;
            float Distance = LdotRR + sqrt(Data.Sphere->Radius2 - D2);

            vec3 NewPoint = RefractedRay * Distance + Data.Point;

            vec3 NewNormal = (Data.Sphere->Position - NewPoint) * Data.Sphere->ODRadius;

            RefractedRay = refract(RefractedRay, NewNormal, Data.Sphere->Eta);

            Data.Color = mix(Data.Color, RayTrace(NewPoint, RefractedRay, Depth + 1, Data.Sphere), Data.Sphere->Refraction);
        }

        if(Data.Sphere->Reflection > 0.0f)
        {
            vec3 ReflectedRay = reflect(Ray, Normal);

            Data.Color = mix(Data.Color, RayTrace(Data.Point, ReflectedRay, Depth + 1, Data.Sphere), Data.Sphere->Reflection);
        }
    }

    return Data.Color;
}

// ----------------------------------------------------------------------------------------------------------------------------

bool CMyRayTracer::InitScene()
{
    bool Error = false;

    Error |= !Floor.CreateTexture2D("floor.jpg");

    Error |= !Cube.CreateTexture2D("cube.jpg");

    Error |= !Earth.CreateTexture2D("earth.jpg");

    if(Error)
    {
        return false;
    }

    if(0) // Textured cube
    {
        QuadsCount = 6;

        Quads = new CQuad[QuadsCount];

        Quads[0] =  CQuad(vec3(-0.5f, -0.5f,  0.5f), vec3( 0.5f, -0.5f,  0.5f), vec3( 0.5f,  0.5f,  0.5f), vec3(-0.5f,  0.5f, 0.5f), vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[1] =  CQuad(vec3( 0.5f, -0.5f, -0.5f), vec3(-0.5f, -0.5f, -0.5f), vec3(-0.5f,  0.5f, -0.5f), vec3( 0.5f,  0.5f,-0.5f), vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[2] =  CQuad(vec3( 0.5f, -0.5f,  0.5f), vec3( 0.5f, -0.5f, -0.5f), vec3( 0.5f,  0.5f, -0.5f), vec3( 0.5f,  0.5f, 0.5f), vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[3] =  CQuad(vec3(-0.5f, -0.5f, -0.5f), vec3(-0.5f, -0.5f,  0.5f), vec3(-0.5f,  0.5f,  0.5f), vec3(-0.5f,  0.5f,-0.5f), vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[4] =  CQuad(vec3(-0.5f,  0.5f,  0.5f), vec3( 0.5f,  0.5f,  0.5f), vec3( 0.5f,  0.5f, -0.5f), vec3(-0.5f,  0.5f,-0.5f), vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[5] =  CQuad(vec3(-0.5f, -0.5f, -0.5f), vec3( 0.5f, -0.5f, -0.5f), vec3( 0.5f, -0.5f,  0.5f), vec3(-0.5f, -0.5f, 0.5f), vec3(1.0f, 1.0f, 1.0f), &Cube);
    }
    else if(0) // Textured sphere
    {
        SpheresCount = 1;

        Spheres = new CSphere[SpheresCount];

        Spheres[0] = CSphere(vec3(0.0f, 0.0f, 0.0f), 0.5f, vec3(1.0f, 1.0f, 1.0f), &Earth);
    }
    else if(0) // 100 random spheres
    {
        SpheresCount = 100;

        Spheres = new CSphere[SpheresCount];

        for(int i = 0; i < SpheresCount; i++)
        {
            #define rnd (float)rand() / (float)RAND_MAX

            vec3 Position = (vec3(rnd, rnd, rnd) * 2.0f - 1.0f) * 2.5f;
            float Radius = 0.125f + rnd * 0.25f;
            vec3 Color = vec3(rnd, rnd, rnd) * 2.0f;
            float Reflection = 0.25f + rnd * 0.5f;

            Spheres[i] = CSphere(Position, Radius, Color, NULL, Reflection);
        }
    }
    else if(0) // 50 random cubes
    {
        QuadsCount = 300;

        Quads = new CQuad[QuadsCount];

        for(int i = 0; i < QuadsCount; i += 6)
        {
            #define rnd (float)rand() / (float)RAND_MAX

            float S = 0.5f + rnd * 0.5f;
            vec3 T = (vec3(rnd, rnd, rnd) * 2.0f - 1.0f) * 2.5f;
            vec3 Color = vec3(rnd, rnd, rnd) * 2.0f;
            float Reflection = 0.25f + rnd * 0.5f;

            Quads[i + 0] =  CQuad(vec3(-0.5f, -0.5f,  0.5f) * S + T, vec3( 0.5f, -0.5f,  0.5f) * S + T, vec3( 0.5f,  0.5f,  0.5f) * S + T, vec3(-0.5f,  0.5f, 0.5f) * S + T, Color, NULL, Reflection);
            Quads[i + 1] =  CQuad(vec3( 0.5f, -0.5f, -0.5f) * S + T, vec3(-0.5f, -0.5f, -0.5f) * S + T, vec3(-0.5f,  0.5f, -0.5f) * S + T, vec3( 0.5f,  0.5f,-0.5f) * S + T, Color, NULL, Reflection);
            Quads[i + 2] =  CQuad(vec3( 0.5f, -0.5f,  0.5f) * S + T, vec3( 0.5f, -0.5f, -0.5f) * S + T, vec3( 0.5f,  0.5f, -0.5f) * S + T, vec3( 0.5f,  0.5f, 0.5f) * S + T, Color, NULL, Reflection);
            Quads[i + 3] =  CQuad(vec3(-0.5f, -0.5f, -0.5f) * S + T, vec3(-0.5f, -0.5f,  0.5f) * S + T, vec3(-0.5f,  0.5f,  0.5f) * S + T, vec3(-0.5f,  0.5f,-0.5f) * S + T, Color, NULL, Reflection);
            Quads[i + 4] =  CQuad(vec3(-0.5f,  0.5f,  0.5f) * S + T, vec3( 0.5f,  0.5f,  0.5f) * S + T, vec3( 0.5f,  0.5f, -0.5f) * S + T, vec3(-0.5f,  0.5f,-0.5f) * S + T, Color, NULL, Reflection);
            Quads[i + 5] =  CQuad(vec3(-0.5f, -0.5f, -0.5f) * S + T, vec3( 0.5f, -0.5f, -0.5f) * S + T, vec3( 0.5f, -0.5f,  0.5f) * S + T, vec3(-0.5f, -0.5f, 0.5f) * S + T, Color, NULL, Reflection);
        }
    }
    else if(0) // Cornell box
    {
        SpheresCount = 1;

        Spheres = new CSphere[SpheresCount];

        Spheres[0] = CSphere(vec3(0.0f, -1.5f, 1.0f), 0.5f, vec3(0.0f, 0.5f, 1.0f), NULL, 0.125f, 0.875f, 1.52f);

        QuadsCount = 17;

        Quads = new CQuad[QuadsCount + LightsCount];

        mat4x4 R = RotationMatrix(22.5f, vec3(0.0f, 1.0f, 0.0f));
        vec3 V = vec3(1.0f, 0.0f, 0.0f);

        Quads[0] =  CQuad(R * vec3(-0.5f, -2.0f,  0.5f) + V, R * vec3( 0.5f, -2.0f,  0.5f) + V, R * vec3( 0.5f, -1.0f,  0.5f) + V, R * vec3(-0.5f, -1.0f,  0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[1] =  CQuad(R * vec3( 0.5f, -2.0f, -0.5f) + V, R * vec3(-0.5f, -2.0f, -0.5f) + V, R * vec3(-0.5f, -1.0f, -0.5f) + V, R * vec3( 0.5f, -1.0f, -0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[2] =  CQuad(R * vec3( 0.5f, -2.0f,  0.5f) + V, R * vec3( 0.5f, -2.0f, -0.5f) + V, R * vec3( 0.5f, -1.0f, -0.5f) + V, R * vec3( 0.5f, -1.0f,  0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[3] =  CQuad(R * vec3(-0.5f, -2.0f, -0.5f) + V, R * vec3(-0.5f, -2.0f,  0.5f) + V, R * vec3(-0.5f, -1.0f,  0.5f) + V, R * vec3(-0.5f, -1.0f, -0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[4] =  CQuad(R * vec3(-0.5f, -1.0f,  0.5f) + V, R * vec3( 0.5f, -1.0f,  0.5f) + V, R * vec3( 0.5f, -1.0f, -0.5f) + V, R * vec3(-0.5f, -1.0f, -0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[5] =  CQuad(R * vec3(-0.5f, -2.0f, -0.5f) + V, R * vec3( 0.5f, -2.0f, -0.5f) + V, R * vec3( 0.5f, -2.0f,  0.5f) + V, R * vec3(-0.5f, -2.0f,  0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        
        Quads[6] =  CQuad(vec3(-2.0f, -2.0f,  2.0f), vec3( 2.0f, -2.0f,  2.0f), vec3( 2.0f, -2.0f, -2.0f), vec3(-2.0f, -2.0f, -2.0f), vec3(1.0f, 1.0f, 1.0f), &Floor, 0.0625f);
        Quads[7] =  CQuad(vec3(-2.0f,  2.0f, -2.0f), vec3( 2.0f,  2.0f, -2.0f), vec3( 2.0f,  2.0f,  2.0f), vec3(-2.0f,  2.0f,  2.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[8] =  CQuad(vec3(-2.0f, -2.0f, -2.0f), vec3( 2.0f, -2.0f, -2.0f), vec3( 2.0f,  2.0f, -2.0f), vec3(-2.0f,  2.0f, -2.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[9] =  CQuad(vec3( 2.0f, -2.0f,  2.0f), vec3(-2.0f, -2.0f,  2.0f), vec3(-2.0f,  2.0f,  2.0f), vec3( 2.0f,  2.0f,  2.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[10] = CQuad(vec3( 2.0f, -2.0f, -2.0f), vec3( 2.0f, -2.0f,  2.0f), vec3( 2.0f,  2.0f,  2.0f), vec3( 2.0f,  2.0f, -2.0f), vec3(0.0f, 1.0f, 0.0f));
        Quads[11] = CQuad(vec3(-2.0f, -2.0f,  2.0f), vec3(-2.0f, -2.0f, -2.0f), vec3(-2.0f,  2.0f, -2.0f), vec3(-2.0f,  2.0f,  2.0f), vec3(1.0f, 0.0f, 0.0f));

        Quads[12] = CQuad(vec3(-0.5f,  1.875f,  0.5f), vec3( 0.5f,  1.875f,  0.5f), vec3( 0.5f,  1.875f, -0.5f), vec3(-0.5f,  1.875f, -0.5f), vec3(1.0f, 1.0f, 1.0f));

        Quads[13] = CQuad(vec3(-0.5f,  1.875f - 0.125f,  0.5f), vec3( 0.5f,  1.875f - 0.125f,  0.5f), vec3( 0.5f,  2.0f - 0.125f,  0.5f), vec3(-0.5f,  2.0f - 0.125f,  0.5f), vec3(1.0f, 1.0f, 1.0f));
        Quads[14] = CQuad(vec3( 0.5f,  1.875f - 0.125f, -0.5f), vec3(-0.5f,  1.875f - 0.125f, -0.5f), vec3(-0.5f,  2.0f - 0.125f, -0.5f), vec3( 0.5f,  2.0f - 0.125f, -0.5f), vec3(1.0f, 1.0f, 1.0f));
        Quads[15] = CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f), vec3(-0.5f,  1.875f - 0.125f,  0.5f), vec3(-0.5f,  2.0f - 0.125f,  0.5f), vec3(-0.5f,  2.0f - 0.125f, -0.5f), vec3(1.0f, 1.0f, 1.0f));
        Quads[16] = CQuad(vec3( 0.5f,  1.875f - 0.125f,  0.5f), vec3( 0.5f,  1.875f - 0.125f, -0.5f), vec3( 0.5f,  2.0f - 0.125f, -0.5f), vec3( 0.5f,  2.0f - 0.125f,  0.5f), vec3(1.0f, 1.0f, 1.0f));

        LightsCount = 1;

        Lights = new CLight[LightsCount];

        Lights[0].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f), vec3( 0.5f,  1.875f - 0.125f, -0.5f), vec3( 0.5f,  1.875f - 0.125f,  0.5f), vec3(-0.5f,  1.875f - 0.125f,  0.5f), vec3(3.0f, 3.0f, 3.0f));
        Lights[0].Ambient = 0.25f;
        Lights[0].Diffuse = 0.75f;
        Lights[0].QuadraticAttenuation = 0.0625f;
    }
    else
    {
        SpheresCount = 3;

        Spheres = new CSphere[SpheresCount];

        Spheres[0] = CSphere(vec3(-2.0f, -1.0f,  2.0f), 0.5f, vec3(0.0f, 0.5f, 1.0f), NULL, 0.875f);
        Spheres[1] = CSphere(vec3( 0.0f, -1.5f,  2.0f), 0.5f, vec3(0.0f, 0.5f, 1.0f), NULL, 0.125f, 0.875f, 1.52f);
        Spheres[2] = CSphere(vec3( 2.0f, -1.5f, -2.0f), 0.5f, vec3(1.0f, 1.0f, 1.0f), &Earth);

        QuadsCount = 21;
        // QuadsCount = 31;

        Quads = new CQuad[QuadsCount];

        LightsCount = 1;
        // LightsCount = 2;
        // LightsCount = 3;

        Lights = new CLight[LightsCount];

        mat4x4 R = RotationMatrix(22.5f, vec3(0.0f, 1.0f, 0.0f));
        vec3 V = vec3(2.0f, 0.0f, 2.0f);

        Quads[0] =  CQuad(R * vec3(-0.5f, -2.0f,  0.5f) + V, R * vec3( 0.5f, -2.0f,  0.5f) + V, R * vec3( 0.5f, -1.0f,  0.5f) + V, R * vec3(-0.5f, -1.0f,  0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[1] =  CQuad(R * vec3( 0.5f, -2.0f, -0.5f) + V, R * vec3(-0.5f, -2.0f, -0.5f) + V, R * vec3(-0.5f, -1.0f, -0.5f) + V, R * vec3( 0.5f, -1.0f, -0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[2] =  CQuad(R * vec3( 0.5f, -2.0f,  0.5f) + V, R * vec3( 0.5f, -2.0f, -0.5f) + V, R * vec3( 0.5f, -1.0f, -0.5f) + V, R * vec3( 0.5f, -1.0f,  0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[3] =  CQuad(R * vec3(-0.5f, -2.0f, -0.5f) + V, R * vec3(-0.5f, -2.0f,  0.5f) + V, R * vec3(-0.5f, -1.0f,  0.5f) + V, R * vec3(-0.5f, -1.0f, -0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[4] =  CQuad(R * vec3(-0.5f, -1.0f,  0.5f) + V, R * vec3( 0.5f, -1.0f,  0.5f) + V, R * vec3( 0.5f, -1.0f, -0.5f) + V, R * vec3(-0.5f, -1.0f, -0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        Quads[5] =  CQuad(R * vec3(-0.5f, -2.0f, -0.5f) + V, R * vec3( 0.5f, -2.0f, -0.5f) + V, R * vec3( 0.5f, -2.0f,  0.5f) + V, R * vec3(-0.5f, -2.0f,  0.5f) + V, vec3(1.0f, 1.0f, 1.0f), &Cube);
        
        Quads[6] =  CQuad(vec3(-0.0f, -2.0f,  4.0f), vec3( 4.0f, -2.0f,  4.0f), vec3( 4.0f, -2.0f, -4.0f), vec3(-0.0f, -2.0f, -4.0f), vec3(1.0f, 1.0f, 1.0f), &Floor, 0.0625f);
        Quads[7] =  CQuad(vec3(-4.0f, -2.0f,  4.0f), vec3( 0.0f, -2.0f,  4.0f), vec3( 0.0f, -2.0f,  0.0f), vec3(-4.0f, -2.0f,  0.0f), vec3(1.0f, 1.0f, 1.0f), &Floor, 0.0625f);
        Quads[8] =  CQuad(vec3( 0.0f,  2.0f, -4.0f), vec3( 4.0f,  2.0f, -4.0f), vec3( 4.0f,  2.0f,  4.0f), vec3( 0.0f,  2.0f,  4.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[9] =  CQuad(vec3(-4.0f,  2.0f,  0.0f), vec3( 0.0f,  2.0f,  0.0f), vec3( 0.0f,  2.0f,  4.0f), vec3(-4.0f,  2.0f,  4.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[10] = CQuad(vec3(-0.0f, -2.0f, -4.0f), vec3( 4.0f, -2.0f, -4.0f), vec3( 4.0f,  2.0f, -4.0f), vec3(-0.0f,  2.0f, -4.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[11] = CQuad(vec3( 4.0f, -2.0f,  4.0f), vec3(-4.0f, -2.0f,  4.0f), vec3(-4.0f,  2.0f,  4.0f), vec3( 4.0f,  2.0f,  4.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[12] = CQuad(vec3( 4.0f, -2.0f, -4.0f), vec3( 4.0f, -2.0f,  4.0f), vec3( 4.0f,  2.0f,  4.0f), vec3( 4.0f,  2.0f, -4.0f), vec3(0.0f, 1.0f, 0.0f));
        Quads[13] = CQuad(vec3(-4.0f, -2.0f,  4.0f), vec3(-4.0f, -2.0f, -0.0f), vec3(-4.0f,  2.0f, -0.0f), vec3(-4.0f,  2.0f,  4.0f), vec3(1.0f, 0.0f, 0.0f));
        Quads[14] = CQuad(vec3(-4.0f, -2.0f,  0.0f), vec3( 0.0f, -2.0f,  0.0f), vec3( 0.0f,  2.0f,  0.0f), vec3(-4.0f,  2.0f,  0.0f), vec3(1.0f, 1.0f, 1.0f));
        Quads[15] = CQuad(vec3( 0.0f, -2.0f,  0.0f), vec3( 0.0f, -2.0f, -4.0f), vec3( 0.0f,  2.0f, -4.0f), vec3( 0.0f,  2.0f,  0.0f), vec3(1.0f, 1.0f, 1.0f));

        vec3 S = vec3(-2.0f, 0.0f, 2.0f);

        Quads[16] = CQuad(vec3(-0.5f,  1.875f,  0.5f) + S, vec3( 0.5f,  1.875f,  0.5f) + S, vec3( 0.5f,  1.875f, -0.5f) + S, vec3(-0.5f,  1.875f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[17] = CQuad(vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[18] = CQuad(vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  2.0f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[19] = CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[20] = CQuad(vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));

        Lights[0].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(3.0f, 3.0f, 3.0f));
        // Lights[0].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Lights[0].Ambient = 0.25f;
        Lights[0].Diffuse = 0.75f;
        // Lights[0].LinearAttenuation = 0.09375f;
        // Lights[0].LinearAttenuation = 0.125f;

        // Lights[1].Sphere = new CSphere(vec3( 2.0f, 0.0f, 2.0f), 0.03125f, vec3(1.0f, 1.0f, 1.0f));
        // Lights[1].Ambient = 0.25f;
        // Lights[1].Diffuse = 0.75f;
        // Lights[1].LinearAttenuation = 0.125f;

        /* Lights[0].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(3.0f, 0.0f, 0.0f));
        // Lights[0].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Lights[0].Ambient = 0.25f;
        Lights[0].Diffuse = 0.75f;
        Lights[0].LinearAttenuation = 0.09375f;
        // Lights[0].LinearAttenuation = 0.125f;

        S.x += 2.0f;

        Quads[21] = CQuad(vec3(-0.5f,  1.875f,  0.5f) + S, vec3( 0.5f,  1.875f,  0.5f) + S, vec3( 0.5f,  1.875f, -0.5f) + S, vec3(-0.5f,  1.875f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[22] = CQuad(vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[23] = CQuad(vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  2.0f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[24] = CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[25] = CQuad(vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));

        Lights[1].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(0.0f, 3.0f, 0.0f));
        // Lights[1].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Lights[1].Ambient = 0.25f;
        Lights[1].Diffuse = 0.75f;
        Lights[1].LinearAttenuation = 0.09375f;
        // Lights[1].LinearAttenuation = 0.125f;

        S.x += 2.0f;

        Quads[26] = CQuad(vec3(-0.5f,  1.875f,  0.5f) + S, vec3( 0.5f,  1.875f,  0.5f) + S, vec3( 0.5f,  1.875f, -0.5f) + S, vec3(-0.5f,  1.875f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[27] = CQuad(vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[28] = CQuad(vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  2.0f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[29] = CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(-0.5f,  2.0f - 0.125f, -0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Quads[30] = CQuad(vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f, -0.5f) + S, vec3( 0.5f,  2.0f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));

        Lights[2].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(0.0f, 0.0f, 3.0f));
        // Lights[2].Quad = new CQuad(vec3(-0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f, -0.5f) + S, vec3( 0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(-0.5f,  1.875f - 0.125f,  0.5f) + S, vec3(1.0f, 1.0f, 1.0f));
        Lights[2].Ambient = 0.25f;
        Lights[2].Diffuse = 0.75f;
        Lights[2].LinearAttenuation = 0.09375f;
        // Lights[2].LinearAttenuation = 0.125f; */
    }

    Camera.LookAt(vec3(0.0f), vec3(0.0f, 0.0f, 8.75f), true);
    // Camera.LookAt(vec3(0.0f), rotate(vec3(0.0f, 0.0f, 8.75f), 45.0f, vec3(0.0f, 1.0f, 0.0f)), true);
    // Camera.LookAt(vec3(0.0f), rotate(vec3(0.0f, 0.0f, 8.75f), 135.0f, vec3(0.0f, 1.0f, 0.0f)), true);
    // Camera.LookAt(vec3(0.0f), rotate(vec3(0.0f, 0.0f, 8.75f), 67.5f, vec3(0.0f, 1.0f, 0.0f)), true);

    return true;
}

void CMyRayTracer::DestroyTextures()
{
    Floor.Destroy();
    Cube.Destroy();
    Earth.Destroy();
}

CMyRayTracer RayTracer;

// ----------------------------------------------------------------------------------------------------------------------------

CWnd::CWnd()
{
    char *moduledirectory = new char[256];
    GetModuleFileName(GetModuleHandle(NULL), moduledirectory, 256);
    *(strrchr(moduledirectory, '\\') + 1) = 0;
    ModuleDirectory = moduledirectory;
    delete [] moduledirectory;
}

CWnd::~CWnd()
{
}

bool CWnd::Create(HINSTANCE hInstance, char *WindowName, int Width, int Height)
{
    WNDCLASSEX WndClassEx;

    memset(&WndClassEx, 0, sizeof(WNDCLASSEX));

    WndClassEx.cbSize = sizeof(WNDCLASSEX);
    WndClassEx.style = CS_OWNDC | CS_HREDRAW | CS_VREDRAW;
    WndClassEx.lpfnWndProc = WndProc;
    WndClassEx.hInstance = hInstance;
    WndClassEx.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    WndClassEx.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
    WndClassEx.hCursor = LoadCursor(NULL, IDC_ARROW);
    WndClassEx.lpszClassName = "Win32CPURayTracerWindow";

    if(RegisterClassEx(&WndClassEx) == 0)
    {
        ErrorLog.Set("RegisterClassEx failed!");
        return false;
    }

    this->WindowName = WindowName;

    this->Width = Width;
    this->Height = Height;

    DWORD Style = WS_OVERLAPPEDWINDOW | WS_CLIPSIBLINGS | WS_CLIPCHILDREN;

    if((hWnd = CreateWindowEx(WS_EX_APPWINDOW, WndClassEx.lpszClassName, WindowName, Style, 0, 0, Width, Height, NULL, NULL, hInstance, NULL)) == NULL)
    {
        ErrorLog.Set("CreateWindowEx failed!");
        return false;
    }

    if((hDC = GetDC(hWnd)) == NULL)
    {
        ErrorLog.Set("GetDC failed!");
        return false;
    }

    return RayTracer.Init();
}

void CWnd::RePaint()
{
    Line = 0;
    InvalidateRect(hWnd, NULL, FALSE);
}

void CWnd::Show(bool Maximized)
{
    RECT dRect, wRect, cRect;

    GetWindowRect(GetDesktopWindow(), &dRect);
    GetWindowRect(hWnd, &wRect);
    GetClientRect(hWnd, &cRect);

    wRect.right += Width - cRect.right;
    wRect.bottom += Height - cRect.bottom;

    wRect.right -= wRect.left;
    wRect.bottom -= wRect.top;

    wRect.left = dRect.right / 2 - wRect.right / 2;
    wRect.top = dRect.bottom / 2 - wRect.bottom / 2;

    MoveWindow(hWnd, wRect.left, wRect.top, wRect.right, wRect.bottom, FALSE);

    ShowWindow(hWnd, Maximized ? SW_SHOWMAXIMIZED : SW_SHOWNORMAL);
}

void CWnd::MsgLoop()
{
    MSG Msg;

    while(GetMessage(&Msg, NULL, 0, 0) > 0)
    {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
}

void CWnd::Destroy()
{
    RayTracer.Destroy();

    DestroyWindow(hWnd);
}

void CWnd::OnKeyDown(UINT Key)
{
    switch(Key)
    {
        case '1':
            if(RayTracer.SetSamples(1)) RePaint();
            break;

        case '2':
            if(RayTracer.SetSamples(2)) RePaint();
            break;

        case '3':
            if(RayTracer.SetSamples(3)) RePaint();
            break;

        case '4':
            if(RayTracer.SetSamples(4)) RePaint();
            break;

        case VK_F1:
            RayTracer.Textures = !RayTracer.Textures;
            RePaint();
            break;

        case VK_F2:
            RayTracer.SoftShadows = !RayTracer.SoftShadows;
            RePaint();
            break;

        case VK_F3:
            RayTracer.AmbientOcclusion = !RayTracer.AmbientOcclusion;
            RePaint();
            break;
    }

    if(Camera.OnKeyDown(Key))
    {
        RePaint();
    }
}

void CWnd::OnMouseMove(int cx, int cy)
{
    if(GetKeyState(VK_RBUTTON) & 0x80)
    {
        Camera.OnMouseMove(LastCurPos.x - cx, LastCurPos.y - cy);

        LastCurPos.x = cx;
        LastCurPos.y = cy;

        RePaint();
    }
}

void CWnd::OnMouseWheel(short zDelta)
{
    Camera.OnMouseWheel(zDelta);

    RePaint();
}

void CWnd::OnPaint()
{
    PAINTSTRUCT ps;

    BeginPaint(hWnd, &ps);

    static DWORD Start;
    static bool RayTracing;

    if(Line == 0)
    {
        RayTracer.ClearColorBuffer();

        // CQuad::Intersections = 0;
        // CSphere::Intersections = 0;

        Start = GetTickCount();

        RayTracing = true;
    }

    DWORD start = GetTickCount();

    while(Line < Height && GetTickCount() - start < 250)
    {
        RayTracer.RayTrace(Line++);
    }

    RayTracer.SwapBuffers(hDC);

    if(RayTracing)
    {
        if(Line == Height)
        {
            RayTracing = false;
            RayTracer.MapHDRColors();
        }

        DWORD End = GetTickCount();

        CString text = WindowName;

        text.Append(" - %dx%d", Width, Height);
        text.Append(", Supersampling %dx", RayTracer.GetSamples());
        text.Append(", Time: %.03f s", (float)(End - Start) * 0.001f);
        // text.Append(", %.02f / %.02f mil. (quad / sphere) intersection tests", (float)CQuad::Intersections * 0.000001f, (float)CSphere::Intersections * 0.000001f);

        SetWindowText(hWnd, text);

        InvalidateRect(hWnd, NULL, FALSE);
    }

    EndPaint(hWnd, &ps);
}

void CWnd::OnRButtonDown(int cx, int cy)
{
    LastCurPos.x = cx;
    LastCurPos.y = cy;
}

void CWnd::OnSize(int Width, int Height)
{
    this->Width = Width;
    this->Height = Height;

    RayTracer.Resize(Width, Height);

    RePaint();
}

CWnd Wnd;

// ----------------------------------------------------------------------------------------------------------------------------

LRESULT CALLBACK WndProc(HWND hWnd, UINT uiMsg, WPARAM wParam, LPARAM lParam)
{
    switch(uiMsg)
    {
        case WM_CLOSE:
            PostQuitMessage(0);
            break;

        case WM_MOUSEMOVE:
            Wnd.OnMouseMove(LOWORD(lParam), HIWORD(lParam));
            break;

        case 0x020A: // WM_MOUSWHEEL
            Wnd.OnMouseWheel(HIWORD(wParam));
            break;

        case WM_KEYDOWN:
            Wnd.OnKeyDown((UINT)wParam);
            break;

        case WM_PAINT:
            Wnd.OnPaint();
            break;

        case WM_RBUTTONDOWN:
            Wnd.OnRButtonDown(LOWORD(lParam), HIWORD(lParam));
            break;

        case WM_SIZE:
            Wnd.OnSize(LOWORD(lParam), HIWORD(lParam));
            break;

        default:
            return DefWindowProc(hWnd, uiMsg, wParam, lParam);
    }

    return 0;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR sCmdLine, int iShow)
{
    SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_HIGHEST);

    if(Wnd.Create(hInstance, "CPU ray tracer", 800, 600))
    {
        Wnd.Show();
        Wnd.MsgLoop();
    }
    else
    {
        MessageBox(NULL, ErrorLog, "Error", MB_OK | MB_ICONERROR);
    }

    Wnd.Destroy();

    return 0;
}