#include "StdAfx.h"
#include "GLRenderer.h"
#include "GL\gl.h"
#include "GL\glu.h"
#include "GL\glaux.h"
#include "GL\glut.h"
#include "DImage.h"
#define M_PI 3.141592653589793238
//#pragma comment(lib, "GL\\glut32.lib")

CGLRenderer::CGLRenderer(void)
    : rotH(0)
    , rotV(0)
{
}

CGLRenderer::~CGLRenderer(void)
{
}

bool CGLRenderer::CreateGLContext(CDC* pDC)
{
    PIXELFORMATDESCRIPTOR pfd ;
    memset(&pfd, 0, sizeof(PIXELFORMATDESCRIPTOR));
    pfd.nSize  = sizeof(PIXELFORMATDESCRIPTOR);
    pfd.nVersion   = 1;
    pfd.dwFlags    = PFD_DOUBLEBUFFER | PFD_SUPPORT_OPENGL | PFD_DRAW_TO_WINDOW;
    pfd.iPixelType = PFD_TYPE_RGBA;
    pfd.cColorBits = 32;
    pfd.cDepthBits = 24;
    pfd.iLayerType = PFD_MAIN_PLANE;

    int nPixelFormat = ChoosePixelFormat(pDC->m_hDC, &pfd);

    if (nPixelFormat == 0) return false;

    BOOL bResult = SetPixelFormat (pDC->m_hDC, nPixelFormat, &pfd);

    if (!bResult) return false;

    m_hrc = wglCreateContext(pDC->m_hDC);

    if (!m_hrc) return false;

    return true;
}

void CGLRenderer::PrepareScene(CDC *pDC)
{
    wglMakeCurrent(pDC->m_hDC, m_hrc);
    //---------------------------------
    glClearColor(0, 0, 0, 1);
    glEnable(GL_DEPTH_TEST);

    texture = LoadTexture(L"texture.bmp");

    //---------------------------------
    wglMakeCurrent(NULL, NULL);
}

void CGLRenderer::DrawScene(CDC *pDC)
{
    wglMakeCurrent(pDC->m_hDC, m_hrc);
    //---------------------------------
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    gluLookAt(10, 10, 5, 0, 0, 0, 0, 1, 0);

    glPushMatrix();
    glRotated(rotV, 1, 0, 0);
    glRotated(rotH, 0, 1, 0);
    EnableLight();

    //CODE
    //CODE
    //CODE
    DrawAxis();
    glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, texture);
    DrawCube(40);

    glDisable(GL_TEXTURE_2D);

    DrawTube(2, 2, 10, 36);
    //CODE
    //CODE
    //CODE
    glPopMatrix();
    glFlush();
    SwapBuffers(pDC->m_hDC);
    //---------------------------------
    wglMakeCurrent(NULL, NULL);
}

void CGLRenderer::Reshape(CDC *pDC, int w, int h)
{
    wglMakeCurrent(pDC->m_hDC, m_hrc);
    //---------------------------------
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glViewport(0, 0, w, h);
    gluPerspective(40, (double)w / (double)h, 1, 1000);
    glMatrixMode(GL_MODELVIEW);

    //---------------------------------
    wglMakeCurrent(NULL, NULL);
}

void CGLRenderer::DestroyScene(CDC *pDC)
{
    wglMakeCurrent(pDC->m_hDC, m_hrc);
    // ...
    glDeleteTextures(1, &texture);
    wglMakeCurrent(NULL,NULL);
    if(m_hrc)
    {
        wglDeleteContext(m_hrc);
        m_hrc = NULL;
    }
}

void CGLRenderer::OnKeyDown(unsigned char nChar)
{
    if (nChar == VK_LEFT) rotV -= 10;
    if (nChar == VK_RIGHT) rotV += 10;
    if (nChar == VK_UP) rotH -= 10;
    if (nChar == VK_DOWN) rotH += 10;
}


void CGLRenderer::DrawAxis()
{
    glBegin(GL_LINES);
    glColor3d(1, 0, 0); glVertex3d(0, 0, 0); glVertex3d(5, 0, 0);
    glColor3d(0, 1, 0); glVertex3d(0, 0, 0); glVertex3d(0, 5, 0);
    glColor3d(0, 0, 1); glVertex3d(0, 0, 0); glVertex3d(0, 0, 5);
    glEnd();
}


unsigned int CGLRenderer::LoadTexture(CString fileName)
{
    unsigned int id;
    DImage img;
    img.Load(fileName);
    glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
    glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
    glGenTextures(1, &id);
    glBindTexture(GL_TEXTURE_2D, id);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);

    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, img.Width(), img.Height(), 0, GL_BGRA_EXT, GL_UNSIGNED_BYTE, img.GetDIBBits());

    return id;
}

void CGLRenderer::DrawCube(double a)
{
    glPushMatrix();
    glTranslated(-a/2, -a/2, -a/2);

    glBegin(GL_QUADS);
    //back
    glVertex3d(0, 0, 0); glTexCoord2d(1, 0);
    glVertex3d(0, a, 0); glTexCoord2d(0, 0);
    glVertex3d(a, a, 0); glTexCoord2d(0, 1);
    glVertex3d(a, 0, 0); glTexCoord2d(1, 1);

    //front
    glVertex3d(0, 0, a); glTexCoord2d(1, 0);
    glVertex3d(0, a, a); glTexCoord2d(0, 0);
    glVertex3d(a, a, a); glTexCoord2d(0, 1);
    glVertex3d(a, 0, a); glTexCoord2d(1, 1);

    //left
    glVertex3d(0, 0, 0); glTexCoord2d(1, 0);
    glVertex3d(0, a, 0); glTexCoord2d(0, 0);
    glVertex3d(0, a, a); glTexCoord2d(0, 1);
    glVertex3d(0, 0, a); glTexCoord2d(1, 1);

    //right
    glVertex3d(a, 0, 0); glTexCoord2d(1, 0);
    glVertex3d(a, a, 0); glTexCoord2d(0, 0);
    glVertex3d(a, a, a); glTexCoord2d(0, 1);
    glVertex3d(a, 0, a); glTexCoord2d(1, 1);

    //bottom
    glVertex3d(0, 0, 0); glTexCoord2d(1, 0);
    glVertex3d(a, 0, 0); glTexCoord2d(0, 0);
    glVertex3d(a, 0, a); glTexCoord2d(0, 1);
    glVertex3d(0, 0, a); glTexCoord2d(1, 1);

    //top
    glVertex3d(0, a, 0); glTexCoord2d(1, 0);
    glVertex3d(a, a, 0); glTexCoord2d(0, 0);
    glVertex3d(a, a, a); glTexCoord2d(0, 1);
    glVertex3d(0, a, a); glTexCoord2d(1, 1);

    glEnd();
    glPopMatrix();
}


void CGLRenderer::DrawCone(double r, double h, double n)
{
    double alfa = 360 / n;
    double str  = 2 * r * sin( (alfa / 2)  / 180 *  M_PI);
    double H = r * cos( (alfa / 2) / 180 *  M_PI);
    glPushMatrix();
    for (int i = 0; i < n; i++)
    {
        glRotated(alfa, 0, 1, 0);
        glBegin(GL_TRIANGLES);
        glVertex3d(H, 0, -str / 2);
        glVertex3d(H, 0, str / 2);
        glVertex3d(0, h, 0);
        glEnd();
    }
    glPopMatrix();
}

void CGLRenderer::DrawTube(double r1, double r2, double h, double n)
{
    double alfa = 360 / n;
    double str = 2 * r1 * sin((alfa / 2) / 180 * M_PI);
    double H = r1 * cos((alfa / 2) / 180 * M_PI);
    double x = r1*r2 / h;
    double clip[] = { 0,-1,0, h - x };
    glEnable(GL_CLIP_PLANE0);
    glClipPlane(GL_CLIP_PLANE0, clip);
    glPushMatrix();
    for (int i = 0; i < n; i++)
    {
        glRotated(alfa, 0, 1, 0);

        if (r1 != r2)
        {
            glBegin(GL_TRIANGLES);
            glVertex3d(H, 0, -str / 2);
            glVertex3d(H, 0, str / 2);
            glVertex3d(0, h, 0);
            glEnd();
        }
        else
        {
            glBegin(GL_QUADS);
            glVertex3d(H, 0, -str / 2);
            glVertex3d(H, h, -str / 2);
            glVertex3d(H, h, +str / 2);
            glVertex3d(H, 0, str / 2);
            glEnd();
        }

    }
    glPopMatrix();
    glDisable(GL_CLIP_PLANE0);
}

void CGLRenderer::EnableLight()
{
    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);
    float ambinet[4] = { 1, 1, 1, 1 };
    float diffuse[4] = { 1, 1, 1, 1 };
    float specular[4] = { 1, 1, 1, 1 };
    float position[4] = { 10, 10, 10, 0 };
    glLightfv(GL_LIGHT0, GL_AMBIENT, ambinet);
    glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
    glLightfv(GL_LIGHT0, GL_SPECULAR, specular);
    glLightfv(GL_LIGHT0, GL_POSITION, position);
}