rostests/tests/txtscale/txtscale.cpp

   1
   2 // ------------------------------------------------------------------
   3 // Windows 2000 Graphics API Black Book
   4 // Chapter 8 - Listing 8.1 (Scaled Text 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 #include <commctrl.h>
  17 #include <cassert>
  18
  19 // for the MakeFont() function...
  20 #include "mk_font.h"
  21 //<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
  22
  23
  24 HINSTANCE hInst;
  25 const char* WndClassName = "GMainWnd";
  26 LRESULT CALLBACK MainWndProc(HWND HWnd, UINT Msg, WPARAM WParam,
  27    LPARAM LParam);
  28
  29
  30 int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE, LPTSTR,
  31    int nCmdShow)
  32 {
  33    hInst = hInstance;
  34
  35    WNDCLASS wc;
  36    memset(&wc, 0, sizeof(WNDCLASS));
  37
  38    wc.style = CS_HREDRAW | CS_VREDRAW;
  39    wc.lpszClassName = WndClassName;
  40    wc.lpfnWndProc = MainWndProc;
  41    wc.hInstance = hInst;
  42    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
  43    wc.hbrBackground = reinterpret_cast<HBRUSH>(
  44       COLOR_BTNFACE + 1
  45       );
  46
  47    if (RegisterClass(&wc))
  48    {
  49       HWND hWnd =
  50          CreateWindow(
  51             WndClassName, TEXT("Scaled Text Demo"),
  52             WS_OVERLAPPEDWINDOW | WS_CAPTION |
  53             WS_VISIBLE | WS_CLIPCHILDREN,
  54             CW_USEDEFAULT, CW_USEDEFAULT, 800, 300,
  55             NULL, NULL, hInst, NULL
  56             );
  57
  58       if (hWnd)
  59       {
  60          ShowWindow(hWnd, nCmdShow);
  61          UpdateWindow(hWnd);
  62
  63          MSG msg;
  64          while (GetMessage(&msg, NULL, 0, 0))
  65          {
  66              TranslateMessage(&msg);
  67              DispatchMessage(&msg);
  68          }
  69       }
  70     }
  71     return 0;
  72 }
  73 //-------------------------------------------------------------------------
  74
  75
  76 HWND hTrackBar = NULL;
  77 HFONT hTTFont = NULL;
  78 double scale = 0.0;
  79 LPCSTR pText = TEXT("The Scaled Text!");
  80
  81 LRESULT CALLBACK MainWndProc(HWND hWnd, UINT msg, WPARAM wParam,
  82    LPARAM lParam)
  83 {
  84    switch (msg)
  85    {
  86       case WM_CREATE:
  87       {
  88          INITCOMMONCONTROLSEX icx;
  89          icx.dwSize = sizeof(INITCOMMONCONTROLSEX);
  90          icx.dwICC = ICC_BAR_CLASSES;
  91
  92          InitCommonControlsEx(&icx);
  93
  94          hTrackBar =
  95             CreateWindow(
  96                TRACKBAR_CLASS, "",
  97                TBS_HORZ | TBS_BOTH | TBS_AUTOTICKS |
  98                TBS_FIXEDLENGTH | TBS_ENABLESELRANGE |
  99                WS_CHILD | WS_VISIBLE,
 100                10, 260, 375, 40,
 101                hWnd, NULL, hInst, NULL
 102                );
 103
 104          assert(hTrackBar != NULL);
 105          SNDMSG(hTrackBar, TBM_SETTHUMBLENGTH, 20, 0);
 106          SNDMSG(hTrackBar, TBM_SETRANGEMAX, TRUE, 100);
 107
 108          // create the TrueType (scalable) font
 109          HDC hDC = GetDC(hWnd);
 110          try
 111          {
 112             // see Chapter 4 for the definition of MakeFont
 113             hTTFont = font::MakeFont(hDC, "Impact", 72);
 114             if (!hTTFont) throw;
 115          }
 116          catch (...)
 117          {
 118             ReleaseDC(hWnd, hDC);
 119          }
 120          ReleaseDC(hWnd, hDC);
 121          break;
 122       }
 123       case WM_HSCROLL:
 124       {
 125          if (reinterpret_cast<HWND>(lParam) == hTrackBar)
 126          {
 127             //
 128             // adjust the scaling factor according to
 129             // the position of the trackbar's slider
 130             //
 131             scale = static_cast<double>(
 132                (SNDMSG(hTrackBar, TBM_GETPOS, 0, 0) + 1) / 50.0
 133                );
 134             InvalidateRect(hWnd, NULL, true);
 135          }
 136          break;
 137       }
 138       case WM_ERASEBKGND:
 139       {
 140          LRESULT res = DefWindowProc(hWnd, msg, wParam, lParam);
 141
 142          HDC hDC = reinterpret_cast<HDC>(wParam);
 143          HFONT hOldFont = static_cast<HFONT>(
 144             SelectObject(hDC, hTTFont)
 145             );
 146          try
 147          {
 148             SetBkMode(hDC, TRANSPARENT);
 149
 150             // open a path bracket
 151             if (!BeginPath(hDC)) throw;
 152
 153             // record the text to the path
 154             TextOut(hDC, 10, 10, pText, lstrlen(pText));
 155
 156             // close the path bracket and
 157             // select the path into hDC
 158             EndPath(hDC);
 159
 160             // determine the number of endpoints in the path
 161             const int num_points = GetPath(hDC, NULL, NULL, 0);
 162             if (num_points > 0)
 163             {
 164                // make room for the POINTs and vertex types
 165                POINT* pPEnds = new POINT[num_points];
 166                unsigned char* pTypes = new unsigned char[num_points];
 167                try
 168                {
 169                   // get the path's description
 170                   int num_got = GetPath(hDC, pPEnds, pTypes, num_points);
 171                   if (num_got > 0)
 172                   {
 173                      // start a new path bracket
 174                      if (!BeginPath(hDC)) throw;
 175
 176                      // scale each point in the description
 177                      int iPoint;
 178                      for (iPoint = 0; iPoint < num_got; ++iPoint)
 179                      {
 180                         pPEnds[iPoint].x = static_cast<LONG>(
 181                            scale * pPEnds[iPoint].x + 0.5
 182                            );
 183                         pPEnds[iPoint].y = static_cast<LONG>(
 184                            scale * pPEnds[iPoint].y + 0.5
 185                            );
 186                      }
 187
 188                      for (iPoint = 0; iPoint < num_points; ++iPoint)
 189                      {
 190                         // handle the MoveToEx case
 191                         if (pTypes[iPoint] == PT_MOVETO)
 192                         {
 193                            MoveToEx(
 194                              hDC, pPEnds[iPoint].x, pPEnds[iPoint].y, NULL
 195                              );
 196                         }
 197                         // handle the LineTo case
 198                         else if (
 199                            pTypes[iPoint] == PT_LINETO ||
 200                            pTypes[iPoint] == (PT_LINETO | PT_CLOSEFIGURE)
 201                            )
 202                         {
 203                            LineTo(hDC, pPEnds[iPoint].x, pPEnds[iPoint].y);
 204                         }
 205                         // handle the PolyBezierTo case
 206                         else if (
 207                            pTypes[iPoint] == PT_BEZIERTO ||
 208                            pTypes[iPoint] == (PT_BEZIERTO | PT_CLOSEFIGURE)
 209                            )
 210                         {
 211                            PolyBezierTo(hDC, pPEnds + iPoint, 3);
 212                            iPoint += 2;
 213                         }
 214                      }
 215
 216                      // close the new path bracket
 217                      EndPath(hDC);
 218
 219                      // stroke and fill the new path
 220                      StrokeAndFillPath(hDC);
 221                   }
 222                }
 223                catch (...)
 224                {
 225                   // clean up
 226                   delete [] pTypes;
 227                   delete [] pPEnds;
 228                   throw;
 229                }
 230                // clean up
 231                delete [] pTypes;
 232                delete [] pPEnds;
 233             }
 234             // ...
 235          }
 236          catch (...)
 237          {
 238             SelectObject(hDC, hOldFont);
 239          }
 240          SelectObject(hDC, hOldFont);
 241          return res;
 242       }
 243       case WM_SIZE:
 244       {
 245          MoveWindow(
 246             hTrackBar,
 247             0, HIWORD(lParam) - 40, LOWORD(lParam), 40,
 248             false
 249             );
 250          break;
 251       }
 252       case WM_DESTROY:
 253       {
 254          // clean up
 255          DeleteObject(hTTFont);
 256          PostQuitMessage(0);
 257          break;
 258       }
 259    }
 260    return DefWindowProc(hWnd, msg, wParam, lParam);
 261 }
 262 //-------------------------------------------------------------------------
 263
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