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

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
HGLRC hGLRC;
HDC   hDC;
__fastcall TForm1::TForm1(TComponent* Owner)
   : TForm(Owner)
{
   hDC = GetDC(Handle);

   int PixelFormat;
   PIXELFORMATDESCRIPTOR pfd =
   {sizeof(PIXELFORMATDESCRIPTOR), 1,
      PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER,
      PFD_TYPE_RGBA, 24, 0,0,0,0,0,0, 0,0, 0,0,0,0,0, 32, 0,
      0, PFD_MAIN_PLANE, 0, 0,0,};
   PixelFormat = ChoosePixelFormat (hDC, &pfd);
   if (SetPixelFormat (hDC, PixelFormat, &pfd) == FALSE)
      Application->Terminate ();

   hGLRC = wglCreateContext(hDC);
   if(hGLRC == NULL) Application->Terminate ();
   if(wglMakeCurrent(hDC, hGLRC) == false) Application->Terminate ();

   glEnable (GL_DEPTH_TEST);

   glViewport (0, 0, Width, Height);

   glShadeModel (GL_SMOOTH);
   glClearColor (0.0, 0.0, 0.0, 1.0);

   glMatrixMode (GL_PROJECTION);
   glLoadIdentity ();
   gluPerspective (90, GLdouble(Width/Height), 1.0, 100.0);

   glMatrixMode (GL_MODELVIEW);
   glLoadIdentity ();
   gluLookAt (0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0);

   Application->OnIdle = AppIdle;

   X = 0; Y = -3;
   Yaw = 0; Pitch = 0;
   IsWire = true;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormResize(TObject *Sender)
{
   glViewport (0, 0, Width, Height);

   glMatrixMode (GL_PROJECTION);
   glLoadIdentity ();
   gluPerspective (90, GLdouble(Width/Height), 1.0, 100.0);

   glMatrixMode (GL_MODELVIEW);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormDestroy(TObject *Sender)
{
   if (hGLRC)
   {
      wglMakeCurrent(NULL, NULL);
      wglDeleteContext(hGLRC);
      hGLRC = NULL;
   }
   if (hDC)
   {
      ReleaseDC(Handle, hDC);
      hDC = NULL;
   }
}
//---------------------------------------------------------------------------
void __fastcall TForm1::AppIdle(TObject *Sender, bool &Done)
{
   Done = true;

   // Начало обработки мыши
   TPoint* temp;
   temp = new TPoint;
   ::GetCursorPos (temp);
   Yaw += (180 * (temp->x - Screen->Width/2) / Screen->Width);
   Pitch += (180 * (temp->y - Screen->Height/2) / Screen->Height);
   ::SetCursorPos (Screen->Width/2, Screen->Height/2);
   // Конец обработки мыши

   glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

   glLoadIdentity ();

   gluLookAt (0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0);
   glRotatef (Pitch, 1, 0, 0);
   glRotatef (Yaw, 0, 0, 1);
   glTranslatef (-X, -Y, 0.0f);

   if (IsWire) glBegin (GL_LINE_STRIP);
   else glBegin (GL_QUADS);

   {  // Нижняя стенка
      glColor3f (1, 0, 0);
      glVertex3f (-1, -1, -1);
      glColor3f (0, 1, 0);
      glVertex3f (-1, 1, -1);
      glColor3f (0, 0, 1);
      glVertex3f (1, 1, -1);
      glColor3f (1, 1, 0);
      glVertex3f (1, -1, -1);
   }
   glEnd ();

   if (IsWire) glBegin (GL_LINE_STRIP);
   else glBegin (GL_QUADS);
   {  // Верхняя стенка
      glColor3f (1, 0, 0);
      glVertex3f (-1, -1, 1);
      glColor3f (0, 1, 0);
      glVertex3f (-1, 1, 1);
      glColor3f (0, 0, 1);
      glVertex3f (1, 1, 1);
      glColor3f (1, 1, 0);
      glVertex3f (1, -1, 1);
   }
   glEnd ();

   if (IsWire) glBegin (GL_LINE_STRIP);
   else glBegin (GL_QUADS);
   {  // Правая стенка
      glColor3f (1, 0, 0);
      glVertex3f (1, -1, -1);
      glColor3f (0, 1, 0);
      glVertex3f (1, 1, -1);
      glColor3f (0, 0, 1);
      glVertex3f (1, 1, 1);
      glColor3f (1, 1, 0);
      glVertex3f (1, -1, 1);
   }
   glEnd ();

   if (IsWire) glBegin (GL_LINE_STRIP);
   else glBegin (GL_QUADS);
   {  // Левая стенка
      glColor3f (1, 0, 0);
      glVertex3f (-1, -1, -1);
      glColor3f (0, 1, 0);
      glVertex3f (-1, 1, -1);
      glColor3f (0, 0, 1);
      glVertex3f (-1, 1, 1);
      glColor3f (1, 1, 0);
      glVertex3f (-1, -1, 1);
   }
   glEnd ();

   if (IsWire) glBegin (GL_LINE_STRIP);
   else glBegin (GL_QUADS);
   {  // Передняя стенка
      glColor3f (1, 0, 0);
      glVertex3f (-1, 1, -1);
      glColor3f (0, 1, 0);
      glVertex3f (1, 1, -1);
      glColor3f (0, 0, 1);
      glVertex3f (1, 1, 1);
      glColor3f (1, 1, 0);
      glVertex3f (-1, 1, 1);
   }
   glEnd ();

   if (IsWire) glBegin (GL_LINE_STRIP);
   else glBegin (GL_QUADS);
   {  // Задяя стенка
      glColor3f (1, 0, 0);
      glVertex3f (-1, -1, -1);
      glColor3f (0, 1, 0);
      glVertex3f (1, -1, -1);
      glColor3f (0, 0, 1);
      glVertex3f (1, -1, 1);
      glColor3f (1, 1, 0);
      glVertex3f (-1, -1, 1);
   }

   glEnd ();

   glFlush ();
   SwapBuffers(hDC);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormKeyDown(TObject *Sender, WORD &Key,
      TShiftState Shift)
{
   float FSIN = sin (Yaw*M_PI/180.0f);
   float FCOS = cos (Yaw*M_PI/180.0f);

   if (Key == VK_ESCAPE) Application->Terminate ();
   else if (Key == VK_LEFT) Yaw -= 3;
   else if (Key == VK_RIGHT) Yaw += 3;
   else if (Key == VK_UP) {X += 0.05 * FSIN; Y += 0.05 * FCOS;}
   else if (Key == VK_DOWN) {X -= 0.05 * FSIN; Y -= 0.05 * FCOS;}

   else if (Key == 'A') {X -= 0.05 * FCOS; Y += 0.05 * FSIN;}
   else if (Key == 'D') {X += 0.05 * FCOS; Y -= 0.05 * FSIN;}
   else if (Key == 'W') {X += 0.05 * FSIN; Y += 0.05 * FCOS;}
   else if (Key == 'S') {X -= 0.05 * FSIN; Y -= 0.05 * FCOS;}

   else if (Key == VK_SPACE) IsWire = !IsWire;
}
//---------------------------------------------------------------------------