src/cocoa/dc.mm

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        src/cocoa/dc.mm
   3 // Purpose:     wxDC
   4 // Author:      David Elliott
   5 // Modified by:
   6 // Created:     2003/04/01
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2003 David Elliott
   9 // Licence:     wxWidgets licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #include "wx/wxprec.h"
  13
  14 #include "wx/dc.h"
  15
  16 #ifndef WX_PRECOMP
  17     #include "wx/log.h"
  18     #include "wx/math.h" //math constants
  19 #endif //WX_PRECOMP
  20
  21 #include "wx/cocoa/autorelease.h"
  22 #include "wx/cocoa/string.h"
  23
  24 #import <AppKit/NSBezierPath.h>
  25 #import <AppKit/NSTextStorage.h>
  26 #import <AppKit/NSLayoutManager.h>
  27 #import <AppKit/NSTextContainer.h>
  28 #import <AppKit/NSGraphicsContext.h>
  29 #import <AppKit/NSAffineTransform.h>
  30 #import <AppKit/NSColor.h>
  31 #import <AppKit/NSTypesetter.h>
  32 #import <AppKit/NSImage.h>
  33
  34 #include "wx/listimpl.cpp"
  35 WX_DEFINE_LIST(wxCocoaDCStack);
  36
  37 IMPLEMENT_ABSTRACT_CLASS(wxDC, wxObject)
  38 WX_NSTextStorage wxDC::sm_cocoaNSTextStorage = nil;
  39 WX_NSLayoutManager wxDC::sm_cocoaNSLayoutManager = nil;
  40 WX_NSTextContainer wxDC::sm_cocoaNSTextContainer = nil;
  41 wxCocoaDCStack wxDC::sm_cocoaDCStack;
  42
  43 inline void CocoaSetPenForNSBezierPath(wxPen &pen, NSBezierPath *bezpath)
  44 {
  45     [pen.GetNSColor() set];
  46     const float *pattern;
  47     [bezpath setLineDash:pattern count:pen.GetCocoaLineDash(&pattern) phase:0.0];
  48     [bezpath setLineWidth:pen.GetWidth()];
  49     switch(pen.GetJoin())
  50     {
  51     case wxJOIN_BEVEL:
  52         [bezpath setLineJoinStyle:NSBevelLineJoinStyle];
  53         break;
  54     case wxJOIN_ROUND:
  55         [bezpath setLineJoinStyle:NSRoundLineJoinStyle];
  56         break;
  57     case wxJOIN_MITER:
  58         [bezpath setLineJoinStyle:NSMiterLineJoinStyle];
  59         break;
  60     }
  61     switch(pen.GetCap())
  62     {
  63     case wxCAP_ROUND:
  64         [bezpath setLineCapStyle:NSRoundLineCapStyle];
  65         break;
  66     case wxCAP_PROJECTING:
  67         [bezpath setLineCapStyle:NSSquareLineCapStyle];
  68         break;
  69     case wxCAP_BUTT:
  70         [bezpath setLineCapStyle:NSButtLineCapStyle];
  71         break;
  72     }
  73 }
  74
  75 void wxDC::CocoaInitializeTextSystem()
  76 {
  77     wxASSERT_MSG(!sm_cocoaNSTextStorage && !sm_cocoaNSLayoutManager && !sm_cocoaNSTextContainer,wxT("Text system already initalized!  BAD PROGRAMMER!"));
  78
  79     sm_cocoaNSTextStorage = [[NSTextStorage alloc] init];
  80
  81     sm_cocoaNSLayoutManager = [[NSLayoutManager alloc] init];
  82     [sm_cocoaNSTextStorage addLayoutManager:sm_cocoaNSLayoutManager];
  83     // NSTextStorage retains NSLayoutManager, but so do we
  84     // [sm_cocoaNSLayoutManager release]; [sm_cocoaNSLayoutManager retain];
  85
  86     // NOTE:  initWithContainerSize is the designated initializer, but the
  87     // Apple CircleView sample gets away with just calling init, which
  88     // is all we really need for our purposes.
  89     sm_cocoaNSTextContainer = [[NSTextContainer alloc] init];
  90     [sm_cocoaNSLayoutManager addTextContainer:sm_cocoaNSTextContainer];
  91     // NSLayoutManager retains NSTextContainer, but so do we
  92     // [sm_cocoaNSTextContainer release]; [sm_cocoaNSTextContainer retain];
  93 }
  94
  95 void wxDC::CocoaShutdownTextSystem()
  96 {
  97     [sm_cocoaNSTextContainer release]; sm_cocoaNSTextContainer = nil;
  98     [sm_cocoaNSLayoutManager release]; sm_cocoaNSLayoutManager = nil;
  99     [sm_cocoaNSTextStorage release]; sm_cocoaNSTextStorage = nil;
 100 }
 101
 102 void wxDC::CocoaUnwindStackAndLoseFocus()
 103 {
 104     wxCocoaDCStack::compatibility_iterator ourNode=sm_cocoaDCStack.Find(this);
 105     if(ourNode)
 106     {
 107         wxCocoaDCStack::compatibility_iterator node=sm_cocoaDCStack.GetFirst();
 108         for(;node!=ourNode; node=sm_cocoaDCStack.GetFirst())
 109         {
 110             wxDC *dc = node->GetData();
 111             wxASSERT(dc);
 112             wxASSERT(dc!=this);
 113             if(!dc->CocoaUnlockFocus())
 114             {
 115                 wxFAIL_MSG(wxT("Unable to unlock focus on higher-level DC!"));
 116             }
 117             sm_cocoaDCStack.Erase(node);
 118         }
 119         wxASSERT(node==ourNode);
 120         wxASSERT(ourNode->GetData() == this);
 121         ourNode->GetData()->CocoaUnlockFocus();
 122         sm_cocoaDCStack.Erase(ourNode);
 123     }
 124 }
 125
 126 bool wxDC::CocoaUnwindStackAndTakeFocus()
 127 {
 128     wxCocoaDCStack::compatibility_iterator node=sm_cocoaDCStack.GetFirst();
 129     for(;node;node = sm_cocoaDCStack.GetFirst())
 130     {
 131         wxDC *dc = node->GetData();
 132         wxASSERT(dc);
 133         // If we're on the stack, then it's unwound enough and we have focus
 134         if(dc==this)
 135             return true;
 136         // If unable to unlockFocus (e.g. wxPaintDC) stop here
 137         if(!dc->CocoaUnlockFocus())
 138             break;
 139         sm_cocoaDCStack.Erase(node);
 140     }
 141     return CocoaLockFocus();
 142 }
 143
 144 wxDC::wxDC(void)
 145 {
 146     m_cocoaWxToBoundsTransform = nil;
 147     m_pen = *wxBLACK_PEN;
 148 }
 149
 150 wxDC::~wxDC(void)
 151 {
 152     [m_cocoaWxToBoundsTransform release];
 153 }
 154
 155 bool wxDC::CocoaLockFocus()
 156 {
 157     return false;
 158 }
 159
 160 bool wxDC::CocoaUnlockFocus()
 161 {
 162     return false;
 163 }
 164
 165 /*static*/ WX_NSAffineTransform wxDC::CocoaGetWxToBoundsTransform(bool isFlipped, float height)
 166 {
 167     NSAffineTransform *transform = nil;
 168     // This transform flips the graphics since wxDC uses top-left origin
 169     if(!isFlipped)
 170     {
 171         // The transform is auto released
 172         transform = [NSAffineTransform transform];
 173         /*  x' = 1x + 0y + 0
 174             y' = 0x + -1y + window's height
 175         */
 176         NSAffineTransformStruct matrix = {
 177             1,  0
 178         ,   0, -1
 179         ,   0, height
 180         };
 181         [transform setTransformStruct: matrix];
 182     }
 183     return transform;
 184 }
 185
 186 void wxDC::CocoaApplyTransformations()
 187 {
 188     [m_cocoaWxToBoundsTransform concat];
 189     // TODO: Apply device/logical/user position/scaling transformations
 190 }
 191
 192 void wxDC::CocoaUnapplyTransformations()
 193 {
 194     // NOTE: You *must* call this with focus held.
 195     // Undo all transforms so we're back in true Cocoa coords with
 196     // no scaling or flipping.
 197     NSAffineTransform *invertTransform;
 198     invertTransform = [m_cocoaWxToBoundsTransform copy];
 199     [invertTransform invert];
 200     [invertTransform concat];
 201     [invertTransform release];
 202 }
 203
 204 bool wxDC::CocoaGetBounds(void *rectData)
 205 {
 206     // We don't know what we are so we can't return anything.
 207     return false;
 208 }
 209
 210 void wxDC::DoDrawRectangle(wxCoord x, wxCoord y, wxCoord width, wxCoord height)
 211 {
 212     wxAutoNSAutoreleasePool pool;
 213     if(!CocoaTakeFocus()) return;
 214     NSBezierPath *bezpath = [NSBezierPath bezierPathWithRect:NSMakeRect(x,y,width,height)];
 215     CocoaSetPenForNSBezierPath(m_pen,bezpath);
 216     [bezpath stroke];
 217     [m_brush.GetNSColor() set];
 218     [bezpath fill];
 219 }
 220
 221 void wxDC::DoDrawLine(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2)
 222 {
 223     wxAutoNSAutoreleasePool pool;
 224     if(!CocoaTakeFocus()) return;
 225     NSBezierPath *bezpath = [NSBezierPath bezierPath];
 226     [bezpath moveToPoint:NSMakePoint(x1,y1)];
 227     [bezpath lineToPoint:NSMakePoint(x2,y2)];
 228
 229     CocoaSetPenForNSBezierPath(m_pen,bezpath);
 230     [bezpath stroke];
 231 }
 232
 233 void wxDC::DoGetTextExtent(const wxString& text, wxCoord *x, wxCoord *y, wxCoord *descent, wxCoord *externalLeading, const wxFont *theFont) const
 234 {
 235     wxAutoNSAutoreleasePool pool;
 236 // FIXME: Cache this so it can be used for DoDrawText
 237     wxASSERT_MSG(sm_cocoaNSTextStorage && sm_cocoaNSLayoutManager && sm_cocoaNSTextContainer, wxT("Text system has not been initialized.  BAD PROGRAMMER!"));
 238     NSAttributedString *attributedString = [[NSAttributedString alloc]
 239             initWithString:wxNSStringWithWxString(text.c_str())];
 240     [sm_cocoaNSTextStorage setAttributedString:attributedString];
 241     [attributedString release];
 242
 243     NSRange glyphRange = [sm_cocoaNSLayoutManager glyphRangeForTextContainer:sm_cocoaNSTextContainer];
 244     NSRect usedRect = [sm_cocoaNSLayoutManager usedRectForTextContainer:sm_cocoaNSTextContainer];
 245     if(x)
 246         *x=(int)usedRect.size.width;
 247     if(y)
 248         *y=(int)usedRect.size.height;
 249     if(descent)
 250         *descent=0;
 251     if(externalLeading)
 252         *externalLeading=0;
 253 }
 254
 255 void wxDC::DoDrawText(const wxString& text, wxCoord x, wxCoord y)
 256 {
 257     wxAutoNSAutoreleasePool pool;
 258     if(!CocoaTakeFocus()) return;
 259     wxASSERT_MSG(sm_cocoaNSTextStorage && sm_cocoaNSLayoutManager && sm_cocoaNSTextContainer, wxT("Text system has not been initialized.  BAD PROGRAMMER!"));
 260     NSAttributedString *attributedString = [[NSAttributedString alloc]
 261             initWithString:wxNSStringWithWxString(text.c_str())];
 262     [sm_cocoaNSTextStorage setAttributedString:attributedString];
 263     [attributedString release];
 264
 265     // Set the color (and later font) attributes
 266     NSColor *fgColor = m_textForegroundColour.GetNSColor();
 267     NSColor *bgColor = m_textBackgroundColour.GetNSColor();
 268     if(!fgColor)
 269         fgColor = [NSColor clearColor];
 270     if(!bgColor)
 271         bgColor = [NSColor clearColor];
 272     NSDictionary *attrDict = [[NSDictionary alloc] initWithObjectsAndKeys:
 273             fgColor, NSForegroundColorAttributeName,
 274             bgColor, NSBackgroundColorAttributeName,
 275             nil];
 276     [sm_cocoaNSTextStorage addAttributes: attrDict range:NSMakeRange(0,[sm_cocoaNSTextStorage length])];
 277     [attrDict release];
 278
 279     NSRange glyphRange = [sm_cocoaNSLayoutManager glyphRangeForTextContainer:sm_cocoaNSTextContainer];
 280     NSRect usedRect = [sm_cocoaNSLayoutManager usedRectForTextContainer:sm_cocoaNSTextContainer];
 281     // NOTE: We'll crash trying to get the location of glyphAtIndex:0 if
 282     // there is no length or we don't start at zero
 283     if(!glyphRange.length)
 284         return;
 285     wxASSERT_MSG(glyphRange.location==0,wxT("glyphRange must begin at zero"));
 286
 287     NSAffineTransform *transform = [NSAffineTransform transform];
 288     [transform translateXBy:x yBy:y];
 289
 290     NSAffineTransform *flipTransform = [NSAffineTransform transform];
 291     /*  x' = 1x + 0y + 0
 292         y' = 0x + -1y + window's height
 293     */
 294     NSAffineTransformStruct matrix = {
 295         1,  0
 296     ,   0, -1
 297     ,   0, usedRect.size.height
 298     };
 299     [flipTransform setTransformStruct: matrix];
 300
 301     NSGraphicsContext *context = [NSGraphicsContext currentContext];
 302     [context saveGraphicsState];
 303     [transform concat];
 304     [flipTransform concat];
 305     #if 0
 306     // Draw+fill a rectangle so we can see where the shit is supposed to be.
 307     wxLogTrace(wxTRACE_COCOA,wxT("(%f,%f) (%fx%f)"),usedRect.origin.x,usedRect.origin.y,usedRect.size.width,usedRect.size.height);
 308     NSBezierPath *bezpath = [NSBezierPath bezierPathWithRect:NSMakeRect(0,0,usedRect.size.width,usedRect.size.height)];
 309     [[NSColor blackColor] set];
 310     [bezpath stroke];
 311     [[NSColor blueColor] set];
 312     [bezpath fill];
 313     #endif
 314
 315     NSPoint layoutLocation = [sm_cocoaNSLayoutManager locationForGlyphAtIndex:0];
 316     layoutLocation.x = 0.0;
 317     layoutLocation.y *= -1.0;
 318     layoutLocation.y += [[sm_cocoaNSLayoutManager typesetter] baselineOffsetInLayoutManager:sm_cocoaNSLayoutManager glyphIndex:0];
 319     if(m_backgroundMode==wxSOLID)
 320         [sm_cocoaNSLayoutManager drawBackgroundForGlyphRange:glyphRange  atPoint:NSZeroPoint];
 321     [sm_cocoaNSLayoutManager drawGlyphsForGlyphRange:glyphRange  atPoint:layoutLocation];
 322
 323     [context restoreGraphicsState];
 324 }
 325
 326 ///////////////////////////////////////////////////////////////////////////
 327 // cut here, the rest is stubs
 328 ///////////////////////////////////////////////////////////////////////////
 329
 330 //-----------------------------------------------------------------------------
 331 // wxDC
 332 //-----------------------------------------------------------------------------
 333
 334 void wxDC::DoDrawIcon( const wxIcon &WXUNUSED(icon), int WXUNUSED(x), int WXUNUSED(y) )
 335 {
 336 };
 337
 338 void wxDC::DoDrawPoint( int x, int y )
 339 {
 340 };
 341
 342 void wxDC::DoDrawPolygon( int, wxPoint *, int, int, int)
 343 {
 344 };
 345
 346 void wxDC::DoDrawLines( int, wxPoint *, int, int )
 347 {
 348 }
 349
 350 int wxDC::GetDepth() const
 351 {
 352     return 0;
 353 }
 354
 355 wxSize wxDC::GetPPI() const
 356 {
 357     return wxSize(0,0);
 358 }
 359
 360 bool wxDC::CanGetTextExtent() const
 361 {
 362     return false;
 363 }
 364
 365 wxCoord wxDC::GetCharHeight() const
 366 {
 367     return 0;
 368 }
 369
 370 wxCoord wxDC::GetCharWidth() const
 371 {
 372     return 0;
 373 }
 374
 375 bool wxDC::CanDrawBitmap() const
 376 {
 377     return true;
 378 }
 379
 380 bool wxDC::DoGetPixel(wxCoord x, wxCoord y, wxColour *col) const
 381 {
 382     return false;
 383 }
 384
 385 void wxDC::DoDrawArc(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2, wxCoord xc, wxCoord yc)
 386 {
 387 }
 388
 389 void wxDC::SetPen(const wxPen& pen)
 390 {
 391     m_pen = pen;
 392 }
 393
 394 void wxDC::SetBrush(const wxBrush& brush)
 395 {
 396     m_brush = brush;
 397 }
 398
 399 void wxDC::DoSetClippingRegionAsRegion(const wxRegion& region)
 400 {
 401 }
 402
 403 void wxDC::DoSetClippingRegion(wxCoord x, wxCoord y, wxCoord width, wxCoord height)
 404 {
 405 }
 406
 407 void wxDC::DestroyClippingRegion()
 408 {
 409 }
 410
 411 void wxDC::DoDrawRoundedRectangle(wxCoord x, wxCoord y, wxCoord width, wxCoord height, double radius)
 412 {
 413 }
 414
 415 void wxDC::DoDrawRotatedText(const wxString& text, wxCoord x, wxCoord y, double angle)
 416 {
 417 }
 418
 419 void wxDC::DoDrawEllipticArc(wxCoord x, wxCoord y, wxCoord w, wxCoord h, double sa, double ea)
 420 {
 421 }
 422
 423 void wxDC::DoDrawEllipse(wxCoord x, wxCoord y, wxCoord width, wxCoord height)
 424 {
 425 }
 426
 427 void wxDC::DoDrawBitmap(const wxBitmap &bmp, wxCoord x, wxCoord y, bool useMask)
 428 {
 429     wxAutoNSAutoreleasePool pool;
 430     if(!CocoaTakeFocus()) return;
 431     if(!bmp.Ok())
 432         return;
 433
 434 #if 0
 435     // Draw a rect so we can see where it's supposed to be
 436     wxLogTrace(wxTRACE_COCOA,wxT("image at (%d,%d) size %dx%d"),x,y,bmp.GetWidth(),bmp.GetHeight());
 437     NSBezierPath *bezpath = [NSBezierPath bezierPathWithRect:NSMakeRect(x,y,bmp.GetWidth(),bmp.GetHeight())];
 438     [[NSColor blackColor] set];
 439     [bezpath stroke];
 440     [[NSColor blueColor] set];
 441     [bezpath fill];
 442 #endif // 0
 443
 444     NSAffineTransform *transform = [NSAffineTransform transform];
 445     [transform translateXBy:x yBy:y];
 446
 447     NSAffineTransform *flipTransform = [NSAffineTransform transform];
 448     /*  x' = 1x + 0y + 0
 449         y' = 0x + -1y + window's height
 450     */
 451     NSAffineTransformStruct matrix = {
 452         1,  0
 453     ,   0, -1
 454     ,   0, bmp.GetHeight()
 455     };
 456     [flipTransform setTransformStruct: matrix];
 457
 458     NSGraphicsContext *context = [NSGraphicsContext currentContext];
 459     [context saveGraphicsState];
 460     [transform concat];
 461     [flipTransform concat];
 462
 463     NSImage *nsimage = [bmp.GetNSImage(useMask) retain];
 464
 465     [nsimage drawAtPoint: NSMakePoint(0,0)
 466         fromRect: NSMakeRect(0.0,0.0,bmp.GetWidth(),bmp.GetHeight())
 467         operation: NSCompositeSourceOver
 468         fraction: 1.0];
 469
 470     [nsimage release];
 471     [context restoreGraphicsState];
 472 }
 473
 474 bool wxDC::DoFloodFill(wxCoord x, wxCoord y, const wxColour& col, int style)
 475 {
 476     return false;
 477 }
 478
 479 void wxDC::DoCrossHair(wxCoord x, wxCoord y)
 480 {
 481 }
 482
 483
 484 bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest, wxCoord width, wxCoord height, wxDC *source, wxCoord xsrc, wxCoord ysrc, int rop, bool useMask , wxCoord xsrcMask, wxCoord ysrcMask)
 485 {
 486     if(!CocoaTakeFocus()) return false;
 487     if(!source) return false;
 488     return source->CocoaDoBlitOnFocusedDC(xdest,ydest,width,height,
 489         xsrc, ysrc, rop, useMask, xsrcMask, ysrcMask);
 490 }
 491
 492 bool wxDC::CocoaDoBlitOnFocusedDC(wxCoord xdest, wxCoord ydest,
 493     wxCoord width, wxCoord height, wxCoord xsrc, wxCoord ysrc,
 494     int logicalFunc, bool useMask, wxCoord xsrcMask, wxCoord ysrcMask)
 495 {
 496     return false;
 497 }
 498
 499 void wxDC::DoGetSize( int* width, int* height ) const
 500 {
 501   *width = m_maxX-m_minX;
 502   *height = m_maxY-m_minY;
 503 };
 504
 505 void wxDC::DoGetSizeMM( int* width, int* height ) const
 506 {
 507   int w = 0;
 508   int h = 0;
 509   GetSize( &w, &h );
 510 };
 511
 512 void wxDC::SetTextForeground( const wxColour &col )
 513 {
 514   if (!Ok()) return;
 515   m_textForegroundColour = col;
 516 };
 517
 518 void wxDC::SetTextBackground( const wxColour &col )
 519 {
 520   if (!Ok()) return;
 521   m_textBackgroundColour = col;
 522 };
 523
 524 void wxDC::Clear()
 525 {
 526     if(!CocoaTakeFocus()) return;
 527
 528     NSRect boundsRect;
 529     if(!CocoaGetBounds(&boundsRect)) return;
 530
 531     NSGraphicsContext *context = [NSGraphicsContext currentContext];
 532     [context saveGraphicsState];
 533
 534     // Undo all transforms so when we draw our bounds rect we
 535     // really overwrite our bounds rect.
 536     CocoaUnapplyTransformations();
 537
 538     [m_backgroundBrush.GetNSColor() set];
 539     [NSBezierPath fillRect:boundsRect];
 540
 541     [context restoreGraphicsState];
 542 }
 543
 544 void wxDC::SetBackground(const wxBrush& brush)
 545 {
 546     m_backgroundBrush = brush;
 547 }
 548
 549 void wxDC::SetPalette(const wxPalette&)
 550 {
 551 }
 552
 553 void wxDC::SetLogicalFunction(int)
 554 {
 555 }
 556
 557
 558 void wxDC::SetMapMode( int mode )
 559 {
 560   switch (mode)
 561   {
 562     case wxMM_TWIPS:
 563       break;
 564     case wxMM_POINTS:
 565       break;
 566     case wxMM_METRIC:
 567       break;
 568     case wxMM_LOMETRIC:
 569       break;
 570     default:
 571     case wxMM_TEXT:
 572       SetLogicalScale( 1.0, 1.0 );
 573       break;
 574   };
 575   if (mode != wxMM_TEXT)
 576   {
 577   };
 578 };
 579
 580 void wxDC::SetUserScale( double x, double y )
 581 {
 582   // allow negative ? -> no
 583   m_userScaleX = x;
 584   m_userScaleY = y;
 585   ComputeScaleAndOrigin();
 586 };
 587
 588 void wxDC::SetLogicalScale( double x, double y )
 589 {
 590   // allow negative ?
 591   m_logicalScaleX = x;
 592   m_logicalScaleY = y;
 593   ComputeScaleAndOrigin();
 594 };
 595
 596 void wxDC::SetLogicalOrigin( wxCoord x, wxCoord y )
 597 {
 598   m_logicalOriginX = x * m_signX;   // is this still correct ?
 599   m_logicalOriginY = y * m_signY;
 600   ComputeScaleAndOrigin();
 601 };
 602
 603 void wxDC::SetDeviceOrigin( wxCoord x, wxCoord y )
 604 {
 605   ComputeScaleAndOrigin();
 606 };
 607
 608 void wxDC::SetAxisOrientation( bool xLeftRight, bool yBottomUp )
 609 {
 610   m_signX = (xLeftRight ?  1 : -1);
 611   m_signY = (yBottomUp  ? -1 :  1);
 612   ComputeScaleAndOrigin();
 613 };
 614
 615 void wxDC::ComputeScaleAndOrigin(void)
 616 {
 617   // CMB: copy scale to see if it changes
 618   double origScaleX = m_scaleX;
 619   double origScaleY = m_scaleY;
 620
 621   m_scaleX = m_logicalScaleX * m_userScaleX;
 622   m_scaleY = m_logicalScaleY * m_userScaleY;
 623
 624   // CMB: if scale has changed call SetPen to recalulate the line width
 625   if (m_scaleX != origScaleX || m_scaleY != origScaleY)
 626   {
 627     // this is a bit artificial, but we need to force wxDC to think
 628     // the pen has changed
 629     const wxPen* pen = & GetPen();
 630     wxPen tempPen;
 631     m_pen = tempPen;
 632     SetPen(* pen);
 633   }
 634 };