C++ OpenGL实现围绕参考点旋转的等距门圆环 支持数量自适应缩放

• 技术栈：C++ + OpenGL
• 核心功能：在空间参考点周围生成由等间距门形元素构成的圆环
• 扩展要求：每次运行程序时圆环内的元素数量可动态调整，程序自动调整缩放比例适配不同的元素数量
• 效果参考：

/**********
 * Includes
 *
 **********/

#include <windows.h>
#include <gl/gl.h>
#include <math.h>

/**********
 * Function Declarations
 *
 **********/

LRESULT CALLBACK WndProc (HWND hWnd, UINT message,
WPARAM wParam, LPARAM lParam);
void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC);
void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC);

int DrawAxis()
{
    float i;
    glClearColor (0 , 1 , 1 , 1);
    glPointSize(1);
    glBegin (GL_POINTS);
    glColor3f(0,0,1);
    for(i=-1;i<1;i=i+0.001)
{
    glVertex2f(i,0);
    glVertex2f(0,i);
}
 glEnd ();
}
int SetPoint(float x , float y, int size)
{

glPointSize(size);
glBegin (GL_POINTS);
glColor3f(1,0,1);
glVertex2f(x , y);
glEnd ();
}
int MovPoint(float x , float y,float xt , float yt, int size)
{

glPointSize(size);
glBegin (GL_POINTS);
glColor3f(1,1,1);
glVertex2f(xt+x/10 , yt+y/10);
glEnd ();
}
int RotatePoint(float x , float y , float Teta)
{
    glPointSize(1);
    glBegin(GL_POINTS);
    glColor3f(1, 1,1);
    Teta = Teta * 3.14 / 180;
    x=x * cos(Teta) - y * sin(Teta);
    y=x * sin(Teta) + y * cos(Teta);
     float teta = 0;
             float i = 0;
             float r=0.4;
             float Dtheta = 2 * 3.14 / 360;
             glColor3f(1,1,1);
             glPointSize(3);
             glBegin (GL_POINTS);
             for (i = 0; i <360; i += 0.01)
                {
                                teta = i * Dtheta;
                   glVertex2f( x+ r * cos(teta)  ,y+  r * sin(teta) );
               }
    
    glEnd();
}
 float dayereh (float x, float y)
         {
         
             float teta = 0;
             float i = 0;
             float r=0.4;
             float Dtheta = 2 * 3.14 / 360;
             glColor3f(1,1,1);
             glPointSize(3);
             glBegin (GL_POINTS);
             for (i = 0; i <360; i += 0.01)
                {
                                teta = i * Dtheta;
                   glVertex2f( x+ r * cos(teta)  ,y+  r * sin(teta) );
               }
                   glEnd ();
          } 


/**********
 * WinMain
 *
 **********/

int WINAPI WinMain (HINSTANCE hInstance,
                    HINSTANCE hPrevInstance,
                    LPSTR lpCmdLine,
                    int iCmdShow)
{
    WNDCLASS wc;
    HWND hWnd;
    HDC hDC;
    HGLRC hRC;        
    MSG msg;
    BOOL bQuit = FALSE;
    float theta = 0.0f;

    /* register window class */
    wc.style = CS_OWNDC;
    wc.lpfnWndProc = WndProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hInstance = hInstance;
    wc.hIcon = LoadIcon (NULL, IDI_APPLICATION);
    wc.hCursor = LoadCursor (NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH) GetStockObject (BLACK_BRUSH);
    wc.lpszMenuName = NULL;
    wc.lpszClassName = "GLSample";
    RegisterClass (&wc);

    /* create main window */
    hWnd = CreateWindow (
      "GLSample", "OpenGL Sample", 
      WS_CAPTION | WS_POPUPWINDOW | WS_VISIBLE,
      550, 60, 456, 456,
      NULL, NULL, hInstance, NULL);

    /* enable OpenGL for the window */
    EnableOpenGL (hWnd, &hDC, &hRC);

    /* program main loop */
    while (!bQuit)
    {
        /* check for messages */
        if (PeekMessage (&msg, NULL, 0, 0, PM_REMOVE))
        {
            /* handle or dispatch messages */
            if (msg.message == WM_QUIT)
            {
                bQuit = TRUE;
            }
            else
            {
                TranslateMessage (&msg);
                DispatchMessage (&msg);
            }
        }
        else
        {
            /* OpenGL animation code goes here */

            glClearColor (0 , 0 , 0 , 1);
            glClear (GL_COLOR_BUFFER_BIT);
            DrawAxis();
         // SetPoint(.9,0,5);
           //MovPoint(0.5,0.5,-0.8,-0.8,5);
            //RotatePoint(.9,0,45);
       //     dayereh (-0.4,0);
          // for (float r = 45; r < 360; r ++)
           //   for (float i = -0.4; i < 0; i += .1)
            for (float j = 0; j < 1; j += .1)
            {
             
             RotatePoint(-0.3, j, 45);
      //       RotatePoint(.6, i, 45);
        ////   RotatePoint(0, i, 45);
             }
        
            //RotatePoint(-0.3,-0.1, 45); 
          //  RotatePoint(-0.3,-0.2, 47); 
           //  RotatePoint(-0.3,-.3, 55);        
            
            SwapBuffers (hDC);

            theta += 0.2f;
            Sleep (1);
        }
    }

    /* shutdown OpenGL */
    DisableOpenGL (hWnd, hDC, hRC);

    /* destroy the window explicitly */
    DestroyWindow (hWnd);

    return msg.wParam;
}


/********
 * Window Procedure
 *
 ********/

LRESULT CALLBACK WndProc (HWND hWnd, UINT message,
                          WPARAM wParam, LPARAM lParam)
{

    switch (message)
    {
    case WM_CREATE:
        return 0;
    case WM_CLOSE:
        PostQuitMessage (0);
        return 0;

    case WM_DESTROY:
        return 0;

    case WM_KEYDOWN:
        switch (wParam)
        {
        case VK_ESCAPE:
            PostQuitMessage(0);
            return 0;
        }
        return 0;

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


/*******
 * Enable OpenGL
 *
 *******/

void EnableOpenGL (HWND hWnd, HDC *hDC, HGLRC *hRC)
{
    PIXELFORMATDESCRIPTOR pfd;
    int iFormat;

    /* get the device context (DC) */
    *hDC = GetDC (hWnd);

    /* set the pixel format for the DC */
    ZeroMemory (&pfd, sizeof (pfd));
    pfd.nSize = sizeof (pfd);
    pfd.nVersion = 1;
    pfd.dwFlags = PFD_DRAW_TO_WINDOW | 
      PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
    pfd.iPixelType = PFD_TYPE_RGBA;
    pfd.cColorBits = 24;
    pfd.cDepthBits = 16;
    pfd.iLayerType = PFD_MAIN_PLANE;
    iFormat = ChoosePixelFormat (*hDC, &pfd);
    SetPixelFormat (*hDC, iFormat, &pfd);

    /* create and enable the render context (RC) */
    *hRC = wglCreateContext( *hDC );
    wglMakeCurrent( *hDC, *hRC );

}


/******
 * Disable OpenGL
 *
 ******/

void DisableOpenGL (HWND hWnd, HDC hDC, HGLRC hRC)
{
    wglMakeCurrent (NULL, NULL);
    wglDeleteContext (hRC);
    ReleaseDC (hWnd, hDC);
}

内容的提问来源于stack exchange，提问作者MNamazi