| 1 | ///////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: dcclient.cpp |
| 3 | // Purpose: wxClientDC class |
| 4 | // Author: David Webster |
| 5 | // Modified by: |
| 6 | // Created: 09/21/99 |
| 7 | // RCS-ID: $Id$ |
| 8 | // Copyright: (c) David Webster |
| 9 | // Licence: wxWindows licence |
| 10 | ///////////////////////////////////////////////////////////////////////////// |
| 11 | |
| 12 | // =========================================================================== |
| 13 | // declarations |
| 14 | // =========================================================================== |
| 15 | |
| 16 | // ---------------------------------------------------------------------------- |
| 17 | // headers |
| 18 | // ---------------------------------------------------------------------------- |
| 19 | |
| 20 | // For compilers that support precompilation, includes "wx.h". |
| 21 | #include "wx/wxprec.h" |
| 22 | |
| 23 | #include "wx/string.h" |
| 24 | #include "wx/log.h" |
| 25 | #include "wx/window.h" |
| 26 | |
| 27 | #include "wx/os2/private.h" |
| 28 | |
| 29 | #include "wx/dcclient.h" |
| 30 | |
| 31 | // ---------------------------------------------------------------------------- |
| 32 | // array/list types |
| 33 | // ---------------------------------------------------------------------------- |
| 34 | |
| 35 | struct WXDLLEXPORT wxPaintDCInfo |
| 36 | { |
| 37 | wxPaintDCInfo(wxWindow *win, wxDC *dc) |
| 38 | { |
| 39 | hwnd = win->GetHWND(); |
| 40 | hdc = dc->GetHDC(); |
| 41 | count = 1; |
| 42 | } |
| 43 | |
| 44 | WXHWND hwnd; // window for this DC |
| 45 | WXHDC hdc; // the DC handle |
| 46 | size_t count; // usage count |
| 47 | }; |
| 48 | |
| 49 | #include "wx/arrimpl.cpp" |
| 50 | |
| 51 | WX_DEFINE_OBJARRAY(wxArrayDCInfo); |
| 52 | |
| 53 | // ---------------------------------------------------------------------------- |
| 54 | // macros |
| 55 | // ---------------------------------------------------------------------------- |
| 56 | |
| 57 | IMPLEMENT_DYNAMIC_CLASS(wxWindowDC, wxDC) |
| 58 | IMPLEMENT_DYNAMIC_CLASS(wxClientDC, wxWindowDC) |
| 59 | IMPLEMENT_DYNAMIC_CLASS(wxPaintDC, wxWindowDC) |
| 60 | |
| 61 | // ---------------------------------------------------------------------------- |
| 62 | // global variables |
| 63 | // ---------------------------------------------------------------------------- |
| 64 | |
| 65 | static RECT g_paintStruct; |
| 66 | |
| 67 | #ifdef __WXDEBUG__ |
| 68 | // a global variable which we check to verify that wxPaintDC are only |
| 69 | // created in resopnse to WM_PAINT message - doing this from elsewhere is a |
| 70 | // common programming error among wxWindows programmers and might lead to |
| 71 | // very subtle and difficult to debug refresh/repaint bugs. |
| 72 | int g_isPainting = 0; |
| 73 | #endif // __WXDEBUG__ |
| 74 | |
| 75 | // =========================================================================== |
| 76 | // implementation |
| 77 | // =========================================================================== |
| 78 | |
| 79 | // ---------------------------------------------------------------------------- |
| 80 | // wxWindowDC |
| 81 | // ---------------------------------------------------------------------------- |
| 82 | |
| 83 | wxWindowDC::wxWindowDC() |
| 84 | { |
| 85 | m_canvas = NULL; |
| 86 | } |
| 87 | |
| 88 | wxWindowDC::wxWindowDC(wxWindow *the_canvas) |
| 89 | { |
| 90 | m_canvas = the_canvas; |
| 91 | m_hDC = (WXHDC) ::WinOpenWindowDC(GetWinHwnd(the_canvas) ); |
| 92 | m_hDCCount++; |
| 93 | // |
| 94 | // default under PM is that Window and Client DC's are the same |
| 95 | // so we offer a separate Presentation Space to use for the |
| 96 | // entire window. Otherwise, calling BeginPaint will just create |
| 97 | // chached-micro client presentation space |
| 98 | // |
| 99 | m_hPS = GpiCreatePS( m_hab |
| 100 | ,m_hDC |
| 101 | ,&m_PageSize |
| 102 | ,PU_PELS | GPIF_LONG | GPIA_ASSOC |
| 103 | ); |
| 104 | ::GpiAssociate(m_hPS, NULLHANDLE); |
| 105 | ::GpiAssociate(m_hPS, m_hDC); |
| 106 | SetBackground(wxBrush(m_canvas->GetBackgroundColour(), wxSOLID)); |
| 107 | } |
| 108 | |
| 109 | wxWindowDC::~wxWindowDC() |
| 110 | { |
| 111 | if (m_canvas && m_hDC) |
| 112 | { |
| 113 | SelectOldObjects(m_hDC); |
| 114 | |
| 115 | // |
| 116 | // In PM one does not explicitly close or release an open WindowDC |
| 117 | // They automatically close with the window, unless explicitly detached |
| 118 | // but we need to destroy our PS |
| 119 | // |
| 120 | ::GpiAssociate(m_hPS, NULLHANDLE); |
| 121 | ::GpiDestroyPS(m_hPS); |
| 122 | m_hPS = NULLHANDLE; |
| 123 | m_hDC = NULLHANDLE; |
| 124 | } |
| 125 | |
| 126 | m_hDCCount--; |
| 127 | } |
| 128 | |
| 129 | // ---------------------------------------------------------------------------- |
| 130 | // wxClientDC |
| 131 | // ---------------------------------------------------------------------------- |
| 132 | |
| 133 | wxClientDC::wxClientDC() |
| 134 | { |
| 135 | m_canvas = NULL; |
| 136 | } |
| 137 | |
| 138 | wxClientDC::wxClientDC(wxWindow *the_canvas) |
| 139 | { |
| 140 | m_canvas = the_canvas; |
| 141 | |
| 142 | // |
| 143 | // default under PM is that Window and Client DC's are the same |
| 144 | // |
| 145 | m_hDC = (WXHDC) ::WinOpenWindowDC(GetWinHwnd(the_canvas)); |
| 146 | |
| 147 | // |
| 148 | // Default mode is BM_LEAVEALONE so we make no call Set the mix |
| 149 | // |
| 150 | SetBackground(wxBrush(m_canvas->GetBackgroundColour(), wxSOLID)); |
| 151 | } |
| 152 | |
| 153 | wxClientDC::~wxClientDC() |
| 154 | { |
| 155 | if ( m_canvas && GetHdc() ) |
| 156 | { |
| 157 | SelectOldObjects(m_hDC); |
| 158 | |
| 159 | // We don't explicitly release Device contexts in PM and |
| 160 | // the cached micro PS is already gone |
| 161 | |
| 162 | m_hDC = 0; |
| 163 | } |
| 164 | } |
| 165 | |
| 166 | // ---------------------------------------------------------------------------- |
| 167 | // wxPaintDC |
| 168 | // ---------------------------------------------------------------------------- |
| 169 | |
| 170 | // VZ: initial implementation (by JACS) only remembered the last wxPaintDC |
| 171 | // created and tried to reuse - this was supposed to take care of a |
| 172 | // situation when a derived class OnPaint() calls base class OnPaint() |
| 173 | // because in this case ::BeginPaint() shouldn't be called second time. |
| 174 | // |
| 175 | // I'm not sure how useful this is, however we must remember the HWND |
| 176 | // associated with the last HDC as well - otherwise we may (and will!) try |
| 177 | // to reuse the HDC for another HWND which is a nice recipe for disaster. |
| 178 | // |
| 179 | // So we store a list of windows for which we already have the DC and not |
| 180 | // just one single hDC. This seems to work, but I'm really not sure about |
| 181 | // the usefullness of the whole idea - IMHO it's much better to not call |
| 182 | // base class OnPaint() at all, or, if we really want to allow it, add a |
| 183 | // "wxPaintDC *" parameter to wxPaintEvent which should be used if it's |
| 184 | // !NULL instead of creating a new DC. |
| 185 | |
| 186 | wxArrayDCInfo wxPaintDC::ms_cache; |
| 187 | |
| 188 | wxPaintDC::wxPaintDC() |
| 189 | { |
| 190 | m_canvas = NULL; |
| 191 | m_hDC = 0; |
| 192 | } |
| 193 | |
| 194 | wxPaintDC::wxPaintDC(wxWindow *canvas) |
| 195 | { |
| 196 | wxCHECK_RET( canvas, wxT("NULL canvas in wxPaintDC ctor") ); |
| 197 | |
| 198 | #ifdef __WXDEBUG__ |
| 199 | if ( g_isPainting <= 0 ) |
| 200 | { |
| 201 | wxFAIL_MSG( wxT("wxPaintDC may be created only in EVT_PAINT handler!") ); |
| 202 | |
| 203 | return; |
| 204 | } |
| 205 | #endif // __WXDEBUG__ |
| 206 | |
| 207 | m_canvas = canvas; |
| 208 | |
| 209 | // do we have a DC for this window in the cache? |
| 210 | wxPaintDCInfo *info = FindInCache(); |
| 211 | if ( info ) |
| 212 | { |
| 213 | m_hDC = info->hdc; |
| 214 | info->count++; |
| 215 | } |
| 216 | else // not in cache, create a new one |
| 217 | { |
| 218 | m_hDC = (WXHDC)::WinBeginPaint(GetWinHwnd(m_canvas), NULLHANDLE, &g_paintStruct); |
| 219 | ms_cache.Add(new wxPaintDCInfo(m_canvas, this)); |
| 220 | } |
| 221 | SetBackground(wxBrush(m_canvas->GetBackgroundColour(), wxSOLID)); |
| 222 | } |
| 223 | |
| 224 | wxPaintDC::~wxPaintDC() |
| 225 | { |
| 226 | if ( m_hDC ) |
| 227 | { |
| 228 | SelectOldObjects(m_hDC); |
| 229 | |
| 230 | size_t index; |
| 231 | wxPaintDCInfo *info = FindInCache(&index); |
| 232 | |
| 233 | wxCHECK_RET( info, wxT("existing DC should have a cache entry") ); |
| 234 | |
| 235 | if ( !--info->count ) |
| 236 | { |
| 237 | ::WinEndPaint(m_hPS); |
| 238 | |
| 239 | ms_cache.Remove(index); |
| 240 | } |
| 241 | //else: cached DC entry is still in use |
| 242 | |
| 243 | // prevent the base class dtor from ReleaseDC()ing it again |
| 244 | m_hDC = 0; |
| 245 | } |
| 246 | } |
| 247 | |
| 248 | wxPaintDCInfo *wxPaintDC::FindInCache(size_t *index) const |
| 249 | { |
| 250 | wxPaintDCInfo *info = NULL; |
| 251 | size_t nCache = ms_cache.GetCount(); |
| 252 | for ( size_t n = 0; n < nCache; n++ ) |
| 253 | { |
| 254 | info = &ms_cache[n]; |
| 255 | if ( info->hwnd == m_canvas->GetHWND() ) |
| 256 | { |
| 257 | if ( index ) |
| 258 | *index = n; |
| 259 | break; |
| 260 | } |
| 261 | } |
| 262 | |
| 263 | return info; |
| 264 | } |