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#include <windows.h> #define DOUBLEBUFFER DBUFF //just to write a clearer name for the member function class DBUFF{ public: DBUFF(); ~DBUFF(); //used to initialise Double Bufferring bool SetBackBuffer(HWND hwnd); //used to close Double Buffering bool FreeBackBuffer(); bool GetState(); BOOL Flip(); bool ClsBackBuffer(const COLORREF); HDC GetBackBuffer(); HDC GetFrontBuffer(); HBITMAP GetBackImage(); BOOL DrawHbitmap(HBITMAP,int,int,int,int); #define BUFFER backhdc HDC backhdc; //the BACKBUFFER of course private: RECT Rectb; //Rect for the window HDC fronthdc; //the windows hdc HWND Winb; //the window HBITMAP backsPixels; //the backbuffer pixels HBITMAP ReservedPixels; //the pixels already in the created HDC backhdc bool on; }; #define ZeroRect(rectangle_rect) (rectangle_rect).left=0; (rectangle_rect).right=0; (rectangle_rect).top=0; (rectangle_rect).bottom=0 DBUFF::DOUBLEBUFFER(){ ZeroRect(this->Rectb); this->fronthdc=NULL; this->backhdc=NULL; this->Winb=NULL; this->backsPixels=NULL; this->ReservedPixels=NULL; this->on=false; } DBUFF::~DOUBLEBUFFER(){ //Remove access to the windows hdc ReleaseDC(this->Winb,this->fronthdc); //Destroy after removing access to.. the backimage SelectObject(this->backhdc,this->ReservedPixels); DeleteObject(this->backsPixels); //Destroy the Back HDC DeleteDC(this->backhdc); } bool DOUBLEBUFFER::SetBackBuffer(HWND hwnd){ //Check hwnd if(!hwnd){return false;} //Equate Window this->Winb=hwnd; //Get the Windows Rectangle if(!GetClientRect(hwnd,&this->Rectb)){return false;} //Get the Windows HDC this->fronthdc=GetDC(hwnd); if(!this->fronthdc){return false;} //Create the HDC compatible with the front hdc this->backhdc=CreateCompatibleDC(this->fronthdc); if(!this->backhdc){return false;} //Create the Image that that HDC will be the selector of.. this->backsPixels=CreateCompatibleBitmap(this->backhdc,this->Rectb.right,this->Rectb.bottom); if(!this->backsPixels){return false;} //Allocate them to each other, and save off into the Reserve this->ReservedPixels=(HBITMAP)SelectObject(this->backhdc,this->backsPixels); if(!this->ReservedPixels){return false;} this->on=true; return true; } bool DOUBLEBUFFER::FreeBackBuffer(){ this->on=false; //Remove access to the windows hdc ReleaseDC(this->Winb,this->fronthdc); //Destroy after removing access to.. the backimage SelectObject(this->backhdc,this->ReservedPixels); DeleteObject(this->backsPixels); //Destroy the Back HDC DeleteDC(this->backhdc); return true; } #define DB_ON 1 #define DB_OFF 0 bool DOUBLEBUFFER::GetState(){ return this->on; } BOOL DBUFF::Flip(){ return BitBlt(this->fronthdc,this->Rectb.left,this->Rectb.top,this->Rectb.right,this->Rectb.bottom,this->backhdc,0,0,SRCCOPY); } bool DBUFF::ClsBackBuffer(const COLORREF colorref){ HBRUSH hbr=CreateSolidBrush(colorref); FillRect(this->backhdc,&this->Rectb,hbr); DeleteObject(hbr); return true; } HDC DBUFF::GetBackBuffer(){ return this->backhdc; } HDC DBUFF::GetFrontBuffer(){ return this->fronthdc; } HBITMAP DBUFF::GetBackImage(){ return this->backsPixels; } BOOL DBUFF::DrawHbitmap(HBITMAP hbmp,int x,int y,int width,int height){ BOOL ReturnBOOL=false; //Create an HDC to use for the HBITMAP HDC BMPhdc=CreateCompatibleDC(this->backhdc); //Select the image into it HBITMAP oldBMP=(HBITMAP)SelectObject(BMPhdc,hbmp); //Blit the HDC against the BackBuffer ReturnBOOL=BitBlt(this->backhdc,x,y,width,height,BMPhdc,0,0,SRCCOPY); SelectObject(BMPhdc,oldBMP); //release the handle to the BMPS DC ReleaseDC(this->Winb,BMPhdc); return ReturnBOOL; } |
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#define MYCLASSNAME "aabs_DB_test_window" #define SCREEN_W 640 #define SCREEN_H 480 LRESULT CALLBACK WndProc(HWND,unsigned int,WPARAM,LPARAM); int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int nShowCmd){ HWND hwnd; MSG msg; DWORD dwWndStyle=WS_OVERLAPPEDWINDOW; RECT rect={0,0,SCREEN_W,SCREEN_H}; bool inval=true; //this is set to true if the screen is to be redrawn DBUFF dbuff; WNDCLASSEX wndclass={0}; wndclass.cbClsExtra =NULL; wndclass.cbSize =sizeof(wndclass); wndclass.cbWndExtra =NULL; wndclass.hbrBackground =(HBRUSH)GetStockObject(BLACK_BRUSH); wndclass.hCursor =LoadCursor(hInstance,IDC_ARROW); wndclass.hIcon =LoadIcon(hInstance,IDI_WINLOGO); wndclass.hIconSm =LoadIcon(hInstance,IDI_WINLOGO); wndclass.hInstance =hInstance; wndclass.lpfnWndProc =WndProc; wndclass.lpszClassName =MYCLASSNAME; wndclass.lpszMenuName =NULL; wndclass.style =CS_VREDRAW|CS_HREDRAW; RegisterClassEx(&wndclass); hwnd=CreateWindowEx(NULL, MYCLASSNAME, MYCLASSNAME, dwWndStyle, 0,0,SCREEN_W,SCREEN_H, NULL, NULL, hInstance, NULL ); ShowWindow(hwnd,nShowCmd); UpdateWindow(hwnd); if(!dbuff.SetBackBuffer(hwnd)){ MessageBox(hwnd,"SetBackBuffer Failed","Error!",MB_OK | MB_ICONERROR); } HBITMAP boxBMP; boxBMP=(HBITMAP)LoadImage(hInstance,"hbitmap.bmp", IMAGE_BITMAP,0,0,LR_LOADFROMFILE); int charX=SCREEN_W/2; int charY=SCREEN_H/2; int charSpeed=3; int hcharW=20; int hcharH=20; while(!KeyHit(VK_ESCAPE)){ if(PeekMessage(&msg,hwnd,0,0,PM_REMOVE)){ if(msg.message==WM_QUIT){break;} TranslateMessage(&msg); DispatchMessage(&msg); }else{ if(KeyDown(VK_LEFT)){ charX-=charSpeed; inval=true; }else if(KeyDown(VK_RIGHT)){ charX+=charSpeed; inval=true; } if(KeyDown(VK_UP)){ charY-=charSpeed; inval=true; }else if(KeyDown(VK_DOWN)){ charY+=charSpeed; inval=true; } if(inval||true){ dbuff.ClsBackBuffer(0); //previous test //Rectangle(dbuff.BUFFER,charX-hcharW,charY-hcharH,charX+hcharW,charY+hcharH); dbuff.DrawHbitmap(boxBMP,charX-64,charY-64,charX+64,charY+64); //appears white SetPixel(dbuff.BUFFER,charX-66,charY-66,0x00FF00FF); dbuff.Flip(); inval=false; } } } DeleteObject(boxBMP); dbuff.FreeBackBuffer(); UnregisterClass(MYCLASSNAME,hInstance); return msg.wParam; } //Basic as it gets LRESULT CALLBACK WndProc(HWND hwnd,unsigned int message,WPARAM wparam,LPARAM lparam){ static PAINTSTRUCT Paint; switch(message){ case WM_PAINT: BeginPaint(hwnd,&Paint); EndPaint(hwnd,&Paint); return 0; case WM_CLOSE: case WM_DESTROY: PostQuitMessage(0); return 0; } return DefWindowProc(hwnd,message,wparam,lparam); } |
