我有用于创建 N 个窗口的多用途代码（在我最新的数据采集应用程序 3 个窗口中显示原始数据）。我创建了一个大小为 800x256 的窗口，并在其中传输了一个 800x256 像素的图像。然后我注意到我忘记了边界，并且得到了奇怪的工件。现在的重点是，我的窗口中有双线。实际显示窗口的宽度为 784 像素（8 到左边框，8 到右边框），所以我希望我的代码会错过几行来绘制，但相反我会得到一些线并排两次。
我得到的现象是，在 784 像素的宽度中，我得到 2 列，每列两次（好像纹理的大小为 782 像素）。
这里发生了什么？
调用代码：
GenerateProfile(lastX, lastY);
OpenGLDisplay_Wrapper((char*)&profile.at(0), 800, 256, false, 8, 1);
轮廓为矢量（800*256）；字符值。
我使用的 OpenGL 代码：
/** Based on code by NeHe tutorials
Adapted to display live camera display with OpenGL
*/
#include "OpenGL-Display.h"
using namespace OGD;
OpenGL_Display::OpenGL_Display(int newId)
{
xPos = -1;
yPos = -1;
ID = newId;
}
OpenGL_Display::~OpenGL_Display()
{
KillGLWindow();
}
void OpenGL_Display::Init_Display(int width, int height, int posX, int posY, LPCSTR className)
{
if (!CreateGLWindow((char*)className, width, height, 24, posX, posY, className))
{
throw;
}
}
LRESULT CALLBACK OpenGL_Display::WndProc( HWND hWnd, // Handle For This Window
UINT uMsg, // Message For This Window
WPARAM wParam, // Additional Message Information
LPARAM lParam) // Additional Message Information
{
switch (uMsg) // Check For Windows Messages
{
case WM_SYSCOMMAND: // Intercept System Commands
{
switch (wParam) // Check System Calls
{
case SC_SCREENSAVE: // Screensaver Trying To Start?
case SC_MONITORPOWER: // Monitor Trying To Enter Powersave?
return 0; // Prevent From Happening
}
break; // Exit
}
case WM_LBUTTONDOWN:
{
for(unsigned int ind = 0; ind < oglDisp.size(); ++ind) {
if(hWnd == oglDisp.at(ind)->hWnd) {
oglDisp.at(ind)->xPos = LOWORD(lParam);
oglDisp.at(ind)->yPos = HIWORD(lParam);
}
}
}
case WM_MOUSEMOVE:
{
for(unsigned int ind = 0; ind < oglDisp.size(); ++ind) {
if((wParam & MK_LBUTTON) && hWnd == oglDisp.at(ind)->hWnd) {
oglDisp.at(ind)->xPos = LOWORD(lParam);
oglDisp.at(ind)->yPos = HIWORD(lParam);
}
}
}
break;
case WM_CLOSE: // Did We Receive A Close Message?
{
PostQuitMessage(0); // Send A Quit Message
return 0; // Jump Back
}
case WM_SIZE: // Resize The OpenGL Window
{
oglDisp.at(0)->ReSizeGLScene(LOWORD(lParam),HIWORD(lParam)); // LoWord=Width, HiWord=Height
return 0; // Jump Back
}
}
// Pass All Unhandled Messages To DefWindowProc
return DefWindowProc(hWnd,uMsg,wParam,lParam);
}
bool OpenGL_Display::CreateGLWindow(char* title, int width, int height, int bits, int posX, int posY, LPCSTR className)
{
GLuint PixelFormat; // Holds The Results After Searching For A Match
WNDCLASS wc; // Windows Class Structure
DWORD dwExStyle; // Window Extended Style
DWORD dwStyle; // Window Style
RECT WindowRect; // Grabs Rectangle Upper Left / Lower Right Values
WindowRect.left=(long)0; // Set Left Value To 0
WindowRect.right=(long)width; // Set Right Value To Requested Width
WindowRect.top=(long)0; // Set Top Value To 0
WindowRect.bottom=(long)height; // Set Bottom Value To Requested Height
hInstance = GetModuleHandle(NULL); // Grab An Instance For Our Window
wc.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC; // Redraw On Size, And Own DC For Window.
wc.lpfnWndProc = WndProc; // WndProc Handles Messages
wc.cbClsExtra = 0; // No Extra Window Data
wc.cbWndExtra = 0; // No Extra Window Data
wc.hInstance = hInstance; // Set The Instance
wc.hIcon = LoadIcon(NULL, IDI_WINLOGO); // Load The Default Icon
wc.hCursor = LoadCursor(NULL, IDC_ARROW); // Load The Arrow Pointer
wc.hbrBackground = NULL; // No Background Required For GL
wc.lpszMenuName = NULL; // We Don't Want A Menu
wc.lpszClassName = className; // Set The Class Name
int error = 0;
if ((error=RegisterClass(&wc))==0) // Attempt To Register The Window Class
{
char* message = new char[256];
sprintf_s(message, 256, "Failed To Register The Window Class. Error: %d", error);
MessageBox(NULL, message,"ERROR",MB_OK|MB_ICONEXCLAMATION);
delete message;
return FALSE; // Return FALSE
}
dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE; // Window Extended Style
dwStyle=WS_VISIBLE | WS_POPUP | WS_CLIPSIBLINGS | WS_CLIPCHILDREN;; // Windows Style
AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle); // Adjust Window To True Requested Size
//HWND hwndC = GetConsoleWindow();
// Create The Window
if (!(hWnd=CreateWindowEx( dwExStyle, // Extended Style For The Window
className, // Class Name
title, // Window Title
WS_OVERLAPPEDWINDOW,
//dwStyle | // Defined Window Style
//WS_CLIPSIBLINGS | // Required Window Style
//WS_CLIPCHILDREN, // Required Window Style
posX, posY, // Window Position
WindowRect.right-WindowRect.left, // Calculate Window Width
WindowRect.bottom-WindowRect.top, // Calculate Window Height
NULL, // No Parent Window
NULL, // No Menu
hInstance, // Instance
NULL))) // Dont Pass Anything To WM_CREATE
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Window Creation Error.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
static PIXELFORMATDESCRIPTOR pfd= // pfd Tells Windows How We Want Things To Be
{
sizeof(PIXELFORMATDESCRIPTOR), // Size Of This Pixel Format Descriptor
1, // Version Number
PFD_DRAW_TO_WINDOW | // Format Must Support Window
PFD_SUPPORT_OPENGL | // Format Must Support OpenGL
PFD_DOUBLEBUFFER, // Must Support Double Buffering
PFD_TYPE_RGBA, // Request An RGBA Format
bits, // Select Our Color Depth
0, 0, 0, 0, 0, 0, // Color Bits Ignored
0, // No Alpha Buffer
0, // Shift Bit Ignored
0, // No Accumulation Buffer
0, 0, 0, 0, // Accumulation Bits Ignored
16, // 16Bit Z-Buffer (Depth Buffer)
0, // No Stencil Buffer
0, // No Auxiliary Buffer
PFD_MAIN_PLANE, // Main Drawing Layer
0, // Reserved
0, 0, 0 // Layer Masks Ignored
};
if (!(hDC=GetDC(hWnd))) // Did We Get A Device Context?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Can't Create A GL Device Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if (!(PixelFormat=ChoosePixelFormat(hDC,&pfd))) // Did Windows Find A Matching Pixel Format?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Can't Find A Suitable PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if(!SetPixelFormat(hDC,PixelFormat,&pfd)) // Are We Able To Set The Pixel Format?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Can't Set The PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if (!(hRC=wglCreateContext(hDC))) // Are We Able To Get A Rendering Context?
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Can't Create A GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
if(!wglMakeCurrent(hDC,hRC)) // Try To Activate The Rendering Context
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Can't Activate The GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
ShowWindow(hWnd,SW_SHOW); // Show The Window
SetForegroundWindow(hWnd); // Slightly Higher Priority
SetFocus(hWnd); // Sets Keyboard Focus To The Window
ReSizeGLScene(width, height); // Set Up Our Perspective GL Screen
if (!InitGL()) // Initialize Our Newly Created GL Window
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Initialization Failed.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
return TRUE; // Success
}
int OpenGL_Display::LoadGLTextures() // Load Bitmaps And Convert To Textures
{
// Load The Bitmap, Check For Errors, If Bitmap's Not Found Quit
glGenTextures(1, &texture); // Create The Texture
// Typical Texture Generation Using Data From The Bitmap
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST); // Minimizing filter, in case display is smaller image size
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST); // Magnifying filter, in case display is smaller image size
return 1; // Return The Status
}
GLvoid OpenGL_Display::ReSizeGLScene(GLsizei width, GLsizei height) // Resize And Initialize The GL Window
{
if (height==0) // Prevent A Divide By Zero
{
height=1; // Making Height Equal One
}
glViewport(0,0,width,height); // Reset The Current Viewport
glMatrixMode(GL_PROJECTION); // Select The Projection Matrix
glLoadIdentity(); // Reset The Projection Matrix
// Calculate The Aspect Ratio Of The Window
gluPerspective(25.0f,1.0f,0.1f,100.0f);
glMatrixMode(GL_MODELVIEW); // Select The Modelview Matrix
glLoadIdentity(); // Reset The Modelview Matrix
}
int OpenGL_Display::InitGL(GLvoid) // All Setup For OpenGL Goes Here
{
if (!LoadGLTextures()) // Jump To Texture Loading Routine
{
return FALSE; // If Texture Didn't Load Return FALSE
}
glEnable(GL_TEXTURE_2D); // Enable Texture Mapping
glShadeModel(GL_SMOOTH); // Enable Smooth Shading
glClearColor(0.0f, 0.0f, 0.0f, 0.5f); // Black Background
glClearDepth(1.0f); // Depth Buffer Setup
glDisable(GL_DEPTH_TEST); // Enables Depth Testing
glDepthFunc(GL_LEQUAL); // The Type Of Depth Testing To Do
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); // Really Nice Perspective Calculations
return TRUE; // Initialization Went OK
}
void OpenGL_Display::GetMouseCords(int& x, int& y) // All Setup For OpenGL Goes Here
{
x = xPos;
y = yPos;
}
void OpenGL_Display::UpdateGLBuffers(int width, int height, char* imageData, int bpp)
{
glBindTexture(GL_TEXTURE_2D, texture);
if(bpp == 8)
{
glTexImage2D(GL_TEXTURE_2D, 0, GL_INTENSITY, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, imageData);
}
else
{
glTexImage2D(GL_TEXTURE_2D, 0, GL_INTENSITY, width, height, 0, GL_RED, GL_UNSIGNED_SHORT, imageData);
}
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);
}
int OpenGL_Display::DrawGLScene(bool flip) // Here's Where We Do All The Drawing
{
GLenum mError = glGetError();
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer
glLoadIdentity(); // Reset The View
glTranslatef(0.0f,0.0f,-5.0f);
mError = glGetError();
glBindTexture(GL_TEXTURE_2D, texture);
mError = glGetError();
glColor4f(1.0, 1.0, 1.0, 1.0);
mError = glGetError();
if(flip)
{
glBegin(GL_QUADS);
// Front Face
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 0.5f);
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 0.5f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 0.5f);
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 0.5f);
glEnd();
mError = glGetError();
}
else
{
glBegin(GL_QUADS);
// Front Face
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, -1.0f, 0.5f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, -1.0f, 0.5f);
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 1.0f, 0.5f);
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 0.5f);
glEnd();
mError = glGetError();
}
mError = glGetError();
return TRUE; // Keep Going
}
GLvoid OpenGL_Display::KillGLWindow(GLvoid) // Properly Kill The Window
{
if (fullscreen) // Are We In Fullscreen Mode?
{
ChangeDisplaySettings(NULL,0); // If So Switch Back To The Desktop
ShowCursor(TRUE); // Show Mouse Pointer
}
if (hRC) // Do We Have A Rendering Context?
{
if (!wglMakeCurrent(NULL,NULL)) // Are We Able To Release The DC And RC Contexts?
{
MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
}
if (!wglDeleteContext(hRC)) // Are We Able To Delete The RC?
{
MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
}
hRC=NULL; // Set RC To NULL
}
if (hDC && !ReleaseDC(hWnd,hDC)) // Are We Able To Release The DC
{
MessageBox(NULL,"Release Device Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hDC=NULL; // Set DC To NULL
}
if (hWnd && !DestroyWindow(hWnd)) // Are We Able To Destroy The Window?
{
MessageBox(NULL,"Could Not Release hWnd.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hWnd=NULL; // Set hWnd To NULL
}
if (!UnregisterClass("OpenGL_Display",hInstance)) // Are We Able To Unregister Class
{
MessageBox(NULL,"Could Not Unregister Class.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hInstance=NULL; // Set hInstance To NULL
}
}
void OpenGL_Display::DrawNewImage(int width, int height, char* imageData, bool flip, int bpp)
{
BOOL returnVal = wglMakeCurrent(hDC, hRC);
UpdateGLBuffers(width, height, imageData, bpp);
DrawGLScene(flip);
SwapBuffers(hDC);
wglMakeCurrent(NULL, NULL);
}
void OpenGLDisplay_Init(int width, int height, int posX, int posY, int ID, LPCSTR className)
{
for(unsigned int i = 0; i < oglDisp.size(); ++i) {
if(oglDisp.at(i)->ID == ID) {
return;
}
}
oglDisp.push_back(new OGD::OpenGL_Display(ID));
oglDisp.at(oglDisp.size()-1)->Init_Display(width, height, posX, posY, className); //by default this ID is latest
wglMakeCurrent(NULL, NULL);
GLenum mError = glGetError();
}
void OpenGLDisplay_Wrapper(char* image, int width, int height, bool flip, int bpp, int ID)
{
for(unsigned int i = 0; i < oglDisp.size(); ++i) {
if(oglDisp.at(i)->ID == ID) {
oglDisp.at(i)->DrawNewImage(width, height, image, flip, bpp);
return;
}
}
}
void OpenGLDisplay_MousePos(int& x, int& y, int ID)
{
for(unsigned int i = 0; i < oglDisp.size(); ++i) {
if(oglDisp.at(i)->ID == ID) {
oglDisp.at(i)->GetMouseCords(x, y);
return;
}
}
}