apps/tests/patblt/patblt.cpp

   1
   2 // ------------------------------------------------------------------
   3 // Windows 2000 Graphics API Black Book
   4 // Chapter 2 - Listing 2.1 (PatBlt Tracking Rect Demo)
   5 //
   6 // Created by Damon Chandler <dmc27@ee.cornell.edu>
   7 // Updates can be downloaded at: <www.coriolis.com>
   8 //
   9 // Please do not hesistate to e-mail me at dmc27@ee.cornell.edu
  10 // if you have any questions about this code.
  11 // ------------------------------------------------------------------
  12
  13
  14 //>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
  15 #include <windows.h>
  16 //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
  17
  18
  19 HINSTANCE HInst;
  20 const char* WndClassName = "GMainWnd";
  21 LRESULT CALLBACK MainWndProc(HWND HWnd, UINT Msg, WPARAM WParam,
  22    LPARAM LParam);
  23
  24
  25 int APIENTRY WinMain(HINSTANCE HInstance, HINSTANCE, LPTSTR,
  26    int nCmdShow)
  27 {
  28    HInst = HInstance;
  29
  30    WNDCLASS wc;
  31    memset(&wc, 0, sizeof(WNDCLASS));
  32
  33    wc.style = CS_VREDRAW | CS_HREDRAW;
  34    wc.lpszClassName = WndClassName;
  35    wc.lpfnWndProc = MainWndProc;
  36    wc.hInstance = HInstance;
  37    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
  38    wc.hbrBackground = static_cast<HBRUSH>(
  39       GetStockObject(BLACK_BRUSH)
  40       );
  41
  42    if (RegisterClass(&wc))
  43    {
  44       HWND HWnd =
  45          CreateWindow(WndClassName,
  46                       TEXT("PatBlt Tracking Rect Demo"),
  47                       WS_OVERLAPPEDWINDOW | WS_CAPTION |
  48                       WS_VISIBLE | WS_CLIPCHILDREN,
  49                       CW_USEDEFAULT, CW_USEDEFAULT, 640, 480,
  50                       NULL, NULL, HInst, NULL);
  51
  52       if (HWnd)
  53       {
  54          ShowWindow(HWnd, nCmdShow);
  55          UpdateWindow(HWnd);
  56
  57          MSG msg;
  58          while (GetMessage(&msg, NULL, 0, 0))
  59          {
  60              TranslateMessage(&msg);
  61              DispatchMessage(&msg);
  62          }
  63       }
  64     }
  65     return 0;
  66 }
  67 //------------------------------------------------------------------
  68
  69
  70 // image related
  71 HDC HMemDC = NULL;
  72 HBITMAP HOldBmp = NULL;
  73 const char* filename = "PENGUIN.BMP";
  74 RECT RImage = {225, 110, 225, 110};
  75
  76 // tracking related
  77 bool is_tracking = false;
  78 HDC HScreenDC = NULL;
  79 POINT PMouse = {0, 0};
  80 RECT RTrack = {0, 0, 0, 0};
  81 const int line_width = 5;
  82
  83
  84 // utility function to map to/from window coordinates
  85 void MapRect(IN HWND HWndFrom, IN HWND HWndTo, IN OUT RECT& RMap)
  86 {
  87    MapWindowPoints(
  88       HWndFrom, HWndTo,
  89       reinterpret_cast<LPPOINT>(&RMap), 2
  90       );
  91 }
  92 //------------------------------------------------------------------
  93
  94
  95 // utility function that uses the PatBlt function to
  96 // render a tracking rectangle
  97 void RenderTrackingRect(IN HDC HDestDC, IN const RECT& RRender)
  98 {
  99    const int width = RRender.right - RRender.left;
 100    const int height = RRender.bottom - RRender.top;
 101    const DWORD dwROP3 = DSTINVERT; // experiment with others
 102
 103    // render top bar
 104    PatBlt(HDestDC,
 105           RRender.left, RRender.top,
 106           width, line_width,
 107           dwROP3);
 108    // render bottom bar
 109    PatBlt(HDestDC,
 110           RRender.left, RRender.bottom - line_width,
 111           width, line_width,
 112           dwROP3);
 113    // render left bar
 114    PatBlt(HDestDC,
 115           RRender.left, RRender.top + line_width,
 116           line_width, height - (2 * line_width),
 117           dwROP3);
 118    // render right bar
 119    PatBlt(HDestDC,
 120           RRender.right - line_width, RRender.top + line_width,
 121           line_width, height - (2 * line_width),
 122           dwROP3);
 123
 124 }
 125 //------------------------------------------------------------------
 126
 127
 128 LRESULT CALLBACK MainWndProc(HWND HWnd, UINT Msg, WPARAM WParam,
 129    LPARAM LParam)
 130 {
 131    switch (Msg)
 132    {
 133       case WM_CREATE:
 134       {
 135          // create a memory DC
 136          HMemDC = CreateCompatibleDC(NULL);
 137          if (HMemDC)
 138          {
 139             // load the penguin bitmap
 140             HBITMAP HBmp = static_cast<HBITMAP>(
 141                LoadImage(HInst, filename, IMAGE_BITMAP, 0, 0,
 142                          LR_LOADFROMFILE | LR_DEFAULTSIZE)
 143                );
 144             if (HBmp)
 145             {
 146                // get the bitmap's dimensions
 147                BITMAP bmp;
 148                if (GetObject(HBmp, sizeof(BITMAP), &bmp))
 149                {
 150                   RImage.right += bmp.bmWidth;
 151                   RImage.bottom += bmp.bmHeight;
 152
 153                   // realize the bitmap
 154                   HOldBmp = static_cast<HBITMAP>(
 155                      SelectObject(HMemDC, HBmp)
 156                      );
 157                }
 158                else DeleteObject(HBmp);
 159             }
 160          }
 161          break;
 162       }
 163       case WM_LBUTTONDOWN:
 164       {
 165          PMouse.x = LOWORD(LParam);
 166          PMouse.y = HIWORD(LParam);
 167
 168          RECT RClient;
 169          if (PtInRect(&RImage, PMouse) &&
 170              GetClientRect(HWnd, &RClient))
 171          {
 172             MapRect(HWnd, HWND_DESKTOP, RClient);
 173             ClipCursor(&RClient);
 174
 175             // grab a handle to the screen DC and clip
 176             // all output to the client area of our window
 177             HScreenDC = GetDC(NULL);
 178             HRGN HClipRgn = CreateRectRgnIndirect(&RClient);
 179             SelectClipRgn(HScreenDC, HClipRgn);
 180             DeleteObject(HClipRgn);
 181
 182             CopyRect(&RTrack, &RImage);
 183             MapRect(HWnd, HWND_DESKTOP, RTrack);
 184
 185             // render the first tracking rect
 186             RenderTrackingRect(HScreenDC, RTrack);
 187             is_tracking = true;
 188          }
 189          break;
 190       }
 191       case WM_MOUSEMOVE:
 192       {
 193          if (HScreenDC && is_tracking)
 194          {
 195             POINT PCurrent = {LOWORD(LParam), HIWORD(LParam)};
 196             const int dX = PCurrent.x - PMouse.x;
 197             const int dY = PCurrent.y - PMouse.y;
 198
 199             // erase the previous rectangle
 200             RenderTrackingRect(HScreenDC, RTrack);
 201             // update the postion
 202             OffsetRect(&RTrack, dX, dY);
 203             // render the new tracking rectangle
 204             RenderTrackingRect(HScreenDC, RTrack);
 205
 206             // update the mouse position
 207             memcpy(&PMouse, &PCurrent, sizeof(POINT));
 208          }
 209          break;
 210       }
 211       case WM_LBUTTONUP:
 212       {
 213          // clean up
 214          if (is_tracking)
 215          {
 216             is_tracking = false;
 217             SelectClipRgn(HScreenDC, NULL);
 218             ReleaseDC(NULL, HScreenDC);
 219
 220             InvalidateRect(HWnd, &RImage, true);
 221             CopyRect(&RImage, &RTrack);
 222             MapRect(HWND_DESKTOP, HWnd, RImage);
 223             InvalidateRect(HWnd, &RImage, true);
 224
 225             ClipCursor(NULL);
 226          }
 227          break;
 228       }
 229       case WM_PAINT:
 230       {
 231          PAINTSTRUCT ps;
 232          HDC Hdc = BeginPaint(HWnd, &ps);
 233          try
 234          {
 235             //
 236             // TODO: Add palette support...
 237             //
 238
 239             // render the penguin
 240             BitBlt(Hdc, RImage.left, RImage.top,
 241                    RImage.right - RImage.left,
 242                    RImage.bottom - RImage.top,
 243                    HMemDC, 0, 0,
 244                    SRCCOPY);
 245          }
 246          catch (...)
 247          {
 248             EndPaint(HWnd, &ps);
 249          }
 250          EndPaint(HWnd, &ps);
 251          break;
 252       }
 253       case WM_DESTROY:
 254       {
 255          // clean up
 256          if (HOldBmp)
 257          {
 258             DeleteObject(SelectObject(HMemDC, HOldBmp));
 259          }
 260          if (HMemDC)
 261          {
 262             DeleteDC(HMemDC);
 263          }
 264          PostQuitMessage(0);
 265          return 0;
 266       }
 267    }
 268    return DefWindowProc(HWnd, Msg, WParam, LParam);
 269 }
 270 //------------------------------------------------------------------