C++ Win32窗口中的OpenGL原语根据窗口大小而扭曲
我用C语言编写了一个简单的OpenGL程序,它可以在一个盒子里画一个旋转的三角形。三角形应该是等边的,但即使窗口宽度和高度相同,三角形顶点也会在沿窗口宽度和长度移动时收缩和拉伸。我能说出来,因为我做了一个静态等角长方体,三角形的顶点在它外面。下面是一个简短的视频片段:请原谅某些时候的延迟 这是我的代码:C++ Win32窗口中的OpenGL原语根据窗口大小而扭曲,c++,c,winapi,opengl,C++,C,Winapi,Opengl,我用C语言编写了一个简单的OpenGL程序,它可以在一个盒子里画一个旋转的三角形。三角形应该是等边的,但即使窗口宽度和高度相同,三角形顶点也会在沿窗口宽度和长度移动时收缩和拉伸。我能说出来,因为我做了一个静态等角长方体,三角形的顶点在它外面。下面是一个简短的视频片段:请原谅某些时候的延迟 这是我的代码: #include <windows.h> #include <gl/gl.h> #include <gl/glu.h> LRESULT CALLBACK W
#include <windows.h>
#include <gl/gl.h>
#include <gl/glu.h>
LRESULT CALLBACK WindowProc(HWND, UINT, WPARAM, LPARAM);
void EnableOpenGL(HWND hwnd, HDC*, HGLRC*);
void DisableOpenGL(HWND, HDC, HGLRC);
void DrawTriangle(float theta);
void DrawBox(void);
int WINAPI WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
WNDCLASSEX wcex;
HWND hwnd;
HDC hDC;
HGLRC hRC;
MSG msg;
BOOL bQuit = FALSE;
float theta = 0.0f;
int i;
/* register window class */
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_OWNDC;
wcex.lpfnWndProc = WindowProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)GetStockObject(BLACK_BRUSH);
wcex.lpszMenuName = NULL;
wcex.lpszClassName = "GLSample";
wcex.hIconSm = LoadIcon(NULL, IDI_APPLICATION);;
if (!RegisterClassEx(&wcex))
return 0;
/* create main window */
hwnd = CreateWindowEx(0,
"GLSample",
"OpenGL Sample",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
500,
500,
NULL,
NULL,
hInstance,
NULL);
ShowWindow(hwnd, nCmdShow);
/* 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(0.0f, 0.0f, 0.0f, 0.0f);
glClear(GL_COLOR_BUFFER_BIT);
DrawTriangle(theta);
DrawBox();
SwapBuffers(hDC);
theta += 1.0f;
Sleep (1);
}
}
/* shutdown OpenGL */
DisableOpenGL(hwnd, hDC, hRC);
/* destroy the window explicitly */
DestroyWindow(hwnd);
return msg.wParam;
}
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
switch (uMsg)
{
case WM_CLOSE:
PostQuitMessage(0);
break;
case WM_DESTROY:
return 0;
case WM_KEYDOWN:
{
switch (wParam)
{
case VK_ESCAPE:
PostQuitMessage(0);
break;
}
}
break;
default:
return DefWindowProc(hwnd, uMsg, wParam, lParam);
}
return 0;
}
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);
}
void DisableOpenGL (HWND hwnd, HDC hDC, HGLRC hRC)
{
wglMakeCurrent(NULL, NULL);
wglDeleteContext(hRC);
ReleaseDC(hwnd, hDC);
}
void DrawTriangle(float theta)
{
glPushMatrix();
if(theta != 0)
{
glRotatef(theta, 0.0f, 0.0f, 1.0f);
}
if(theta == 1)
{
glRotatef(89, 0.0f, 0.0f, 1.0f);
}
glBegin(GL_TRIANGLES);
glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(0.0f, 0.50f);
glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(0.45f, -0.50f);
glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(-0.45f, -0.50f);
glEnd();
glPopMatrix();
}
void DrawBox(void)
{
glPushMatrix();
glBegin(GL_LINE_LOOP);
glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(0.45f, 0.5f); /*I decremented each x value by 0.05 to compensate for the bullshit with the window throwing off scale*/
glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(0.45f, -0.5f);
glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(-0.45f, -0.5f);
glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(-0.45f, 0.5f);
glEnd();
glPopMatrix();
}
#包括
#包括
#包括
LRESULT回调WindowProc(HWND、UINT、WPARAM、LPARAM);
void EnableOpenGL(HWND-HWND、HDC*、HGLRC*);
无效禁用OpenGL(HWND、HDC、HGLRC);
空心三角形(浮动θ);
空抽屉(空);
int WINAPI WinMain(HINSTANCE HINSTANCE,
HINSTANCE HPPrevenstance,
LPSTR lpCmdLine,
国际展览(nCmdShow)
{
WNDCLASSEX wcex;
HWND-HWND;
HDC-HDC;
HGLRC人权委员会;
味精;
BOOL bkuit=假;
浮动θ=0.0f;
int i;
/*注册窗口类*/
wcex.cbSize=sizeof(WNDCLASSEX);
wcex.style=CS_OWNDC;
wcex.lpfnWndProc=WindowProc;
wcex.cbClsExtra=0;
wcex.cbWndExtra=0;
wcex.hInstance=hInstance;
wcex.hIcon=LoadIcon(空,IDI_应用程序);
wcex.hCursor=LoadCursor(空,IDC_箭头);
wcex.hbrBackground=(HBRUSH)GetStockObject(黑色画笔);
wcex.lpszMenuName=NULL;
wcex.lpszClassName=“GLSample”;
wcex.hIconSm=LoadIcon(NULL,IDI_应用程序);;
如果(!RegisterClassEx(&wcex))
返回0;
/*创建主窗口*/
hwnd=CreateWindowEx(0,
“GLSample”,
“OpenGL示例”,
WS_重叠窗口,
CW_使用默认值,
CW_使用默认值,
500,
500,
无效的
无效的
hInstance,
无效);
显示窗口(hwnd、nCmdShow);
/*为窗口启用OpenGL*/
启用OpenGL(hwnd、hDC和hRC);
/*程序主循环*/
而(!bguit)
{
/*检查消息*/
if(peek消息(&msg,NULL,0,0,PM_-REMOVE))
{
/*处理或发送消息*/
如果(msg.message==WM\u退出)
{
bkuit=TRUE;
}
其他的
{
翻译信息(&msg);
发送消息(&msg);
}
}
其他的
{
/*OpenGL动画代码在这里*/
glClearColor(0.0f、0.0f、0.0f、0.0f);
glClear(GLU颜色缓冲位);
绘制三角形(θ);
抽屉();
SwapBuffers(hDC);
θ+=1.0f;
睡眠(1);
}
}
/*关闭OpenGL*/
禁用OpenGL(hwnd、hDC、hRC);
/*显式销毁窗口*/
窗口(hwnd);
返回msg.wParam;
}
LRESULT回调WindowProc(HWND HWND、UINT uMsg、WPARAM WPARAM、LPARAM LPARAM)
{
开关(uMsg)
{
案例WM_结束:
PostQuitMessage(0);
打破
案例WM_销毁:
返回0;
案例WM_键控:
{
交换机(wParam)
{
案件VK_逃逸:
PostQuitMessage(0);
打破
}
}
打破
违约:
返回DefWindowProc(hwnd、uMsg、wParam、lParam);
}
返回0;
}
启用void的OpenGL(HWND HWND、HDC*HDC、HGLRC*hRC)
{
像素描述符pfd;
内形;
/*获取设备上下文(DC)*/
*hDC=GetDC(hwnd);
/*设置DC的像素格式*/
零内存(&pfd,sizeof(pfd));
pfd.nSize=sizeof(pfd);
pfd.inversion=1;
pfd.dwFlags=pfd\u DRAW\u TO\u窗口|
PFD_支持OPENGL | PFD_双缓冲区;
pfd.iPixelType=pfd_TYPE_RGBA;
pfd.cColorBits=24;
pfd.cDepthBits=16;
pfd.iLayerType=pfd_主平面;
iFormat=选择固定格式(*hDC和pfd);
SetPixelFormat(*hDC、iFormat和pfd);
/*创建并启用渲染上下文(RC)*/
*hRC=wglCreateContext(*hDC);
wglMakeCurrent(*hDC,*hRC);
}
无效禁用OpenGL(HWND HWND、HDC HDC、HGLRC hRC)
{
wglMakeCurrent(NULL,NULL);
背景(hRC);
释放DC(hwnd、hDC);
}
空心三角形(浮动θ)
{
glPushMatrix();
如果(θ!=0)
{
glRotatef(θ,0.0f,0.0f,1.0f);
}
如果(θ=1)
{
glRotatef(89,0.0f,0.0f,1.0f);
}
glBegin(GL_三角形);
glColor3f(1.0f,0.0f,0.0f);glVertex2f(0.0f,0.50f);
glColor3f(1.0f,0.0f,0.0f);glVertex2f(0.45f,-0.50f);
glColor3f(1.0f,0.0f,0.0f);glVertex2f(-0.45f,-0.50f);
格伦德();
glPopMatrix();
}
空抽屉(空)
{
glPushMatrix();
glBegin(GL_线_环);
glColor3f(1.0f,0.0f,0.0f);glVertex2f(0.45f,0.5f);/*我将每个x值递减0.05,以补偿窗口偏离刻度的胡说八道*/
glColor3f(1.0f,0.0f,0.0f);glVertex2f(0.45f,-0.5f);
glColor3f(1.0f,0.0f,0.0f);glVertex2f(-0.45f,-0.5f);
glColor3f(1.0f,0.0f,0.0f);glVertex2f(-0.45f,0.5f);
格伦德();
glPopMatrix();
}
您使用的坐标不跨越等边三角形。等边三角形总是有三条长度相同的边。在您的示例中,底部的长度为0.9,但其他两个的长度为sqrt(0.45^2+1.0^2)=1.097。即使假设取0.45而不是0.5,这仍然不是等边的。(底部=1.0,其他侧=sqrt(0.5^2+1.0^2)=1.12)
正如您已经注意到的,您必须补偿可渲染区域的纵横比(当将500x500传递到CreateWindowEx
时,这不是二次的,因为标题栏