自学教程：C++ GetCanvas函数代码示例

void DISPLAY_FOOTPRINTS_FRAME::InitDisplay(){    wxString msg;    CVPCB_MAINFRAME* parentframe = (CVPCB_MAINFRAME *) GetParent();    wxString footprintName = parentframe->m_footprintListBox->GetSelectedFootprint();    if( !footprintName.IsEmpty() )    {        msg.Printf( _( "Footprint: %s" ), GetChars( footprintName ) );        SetTitle( msg );        const FOOTPRINT_INFO* module_info = parentframe->m_footprints.GetModuleInfo( footprintName );        const wxChar* libname;        if( module_info )            libname = GetChars( module_info->GetNickname() );        else            libname = GetChars( wxT( "???" ) );        msg.Printf( _( "Lib: %s" ), libname );        SetStatusText( msg, 0 );        if( GetBoard()->m_Modules.GetCount() )        {            // there is only one module in the list            GetBoard()->m_Modules.DeleteAll();        }        MODULE* module = Get_Module( footprintName );        if( module )            GetBoard()->m_Modules.PushBack( module );        Zoom_Automatique( false );    }    else   // No footprint to display. Erase old footprint, if any    {        if( GetBoard()->m_Modules.GetCount() )        {            GetBoard()->m_Modules.DeleteAll();            Zoom_Automatique( false );            SetStatusText( wxEmptyString, 0 );        }    }    // Display new cursor coordinates and zoom value:    UpdateStatusBar();    GetCanvas()->Refresh();    if( m_Draw3DFrame )        m_Draw3DFrame->NewDisplay();}

void PCB_EDIT_FRAME::Swap_Layers( wxCommandEvent& event ){    PCB_LAYER_ID new_layer[PCB_LAYER_ID_COUNT];    DIALOG_SWAP_LAYERS dlg( this, new_layer );    if( dlg.ShowModal() != wxID_OK )        return;    BOARD_COMMIT commit( this );    bool hasChanges = false;    // Change tracks.    for( TRACK* segm = GetBoard()->m_Track;  segm;  segm = segm->Next() )    {        if( segm->Type() == PCB_VIA_T )        {            VIA*         via = (VIA*) segm;            PCB_LAYER_ID top_layer, bottom_layer;            if( via->GetViaType() == VIA_THROUGH )                continue;            via->LayerPair( &top_layer, &bottom_layer );            if( new_layer[bottom_layer] != bottom_layer || new_layer[top_layer] != top_layer )            {                commit.Modify( via );                via->SetLayerPair( new_layer[top_layer], new_layer[bottom_layer] );                GetGalCanvas()->GetView()->Update( via, KIGFX::GEOMETRY );                hasChanges = true;            }        }        else        {            hasChanges |= processBoardItem( this, commit, segm, new_layer );        }    }    for( BOARD_ITEM* zone : GetBoard()->Zones() )    {        hasChanges |= processBoardItem( this, commit, zone, new_layer );    }    for( BOARD_ITEM* drawing : GetBoard()->Drawings() )    {        hasChanges |= processBoardItem( this, commit, drawing, new_layer );    }    if( hasChanges )    {        OnModify();        commit.Push( "Layers moved" );        GetCanvas()->Refresh();    }}

void wxCompositeShape::OnDragLeft(bool WXUNUSED(draw), double x, double y, int WXUNUSED(keys), int WXUNUSED(attachment)){	double xx = x;	double yy = y;	m_canvas->Snap(&xx, &yy);	double offsetX = xx - objectStartX;	double offsetY = yy - objectStartY;	wxClientDC dc(GetCanvas());	GetCanvas()->PrepareDC(dc);	dc.SetLogicalFunction(OGLRBLF);	wxPen dottedPen(wxColour(0, 0, 0), 1, wxDOT);	dc.SetPen(dottedPen);	dc.SetBrush((* wxTRANSPARENT_BRUSH));	GetEventHandler()->OnDrawOutline(dc, GetX() + offsetX, GetY() + offsetY, GetWidth(), GetHeight());//  wxShape::OnDragLeft(draw, x, y, keys, attachment);}

voidTGUIStimulusView::Paint(){    if( bitmap == NULL )        return;    // Draw the bitmap.    if( visible )        GetCanvas()->Draw( bitmapTRect.Left, bitmapTRect.Top, bitmap );}

void StagePanel::OnPreview(){	int width, height;	QueryWindowViewSizeSJ::Instance()->Query(width, height);	std::vector<ee::SprPtr> sprs;	TraverseSprites(ee::FetchAllRefVisitor<ee::Sprite>(sprs));	EnableObserve(false);	GetCanvas()->EnableObserve(false);	GetStageImpl()->EnableObserve(false);	PreviewDialog dlg(const_cast<StagePanel*>(this), GetCanvas()->GetGLContext(), width, height, sprs);	dlg.ShowModal();	EnableObserve(true);	GetCanvas()->EnableObserve(true);	GetStageImpl()->EnableObserve(true);}

void wxDiagram::ReadLines(wxExprDatabase& database){  database.BeginFind();  wxExpr *clause = database.FindClauseByFunctor(_T("line"));  while (clause)  {    wxString type;    long parentId = -1;    clause->GetAttributeValue(_T("type"), type);    clause->GetAttributeValue(_T("parent"), parentId);    wxClassInfo *classInfo = wxClassInfo::FindClass(type);    if (classInfo)    {      wxLineShape *shape = (wxLineShape *)classInfo->CreateObject();      shape->Show(true);      OnShapeLoad(database, *shape, *clause);      shape->SetCanvas(GetCanvas());      long image_to = -1; long image_from = -1;      clause->GetAttributeValue(_T("to"), image_to);      clause->GetAttributeValue(_T("from"), image_from);      wxExpr *image_to_expr = database.HashFind(_T("shape"), image_to);      if (!image_to_expr)      {        // Error      }      wxExpr *image_from_expr = database.HashFind(_T("shape"), image_from);      if (!image_from_expr)      {        // Error      }      if (image_to_expr && image_from_expr)      {        wxShape *image_to_object = (wxShape *)image_to_expr->GetClientData();        wxShape *image_from_object = (wxShape *)image_from_expr->GetClientData();        if (image_to_object && image_from_object)        {          image_from_object->AddLine(shape, image_to_object, shape->GetAttachmentFrom(), shape->GetAttachmentTo());        }      }      clause->SetClientData(shape);      m_shapeList->Append(shape);    }    clause = database.FindClauseByFunctor(_T("line"));  }}

bool wxDivisionShape::AdjustBottom(double bottom, bool test){	double y1 = (double)(GetY() - (GetHeight() / 2.0));	if (bottom <= y1)		return FALSE;	if (test)		return TRUE;	double newH = bottom - y1;	double newY = (double)(y1 + newH / 2.0);	SetSize(GetWidth(), newH);	Move(GetX(), newY);	if (GetCanvas())		GetCanvas()->Refresh();	return TRUE;}

// Adjust a side, returning false if it's not physically possible.bool wxDivisionShape::AdjustLeft(double left, bool test){  double x2 = (double)(GetX() + (GetWidth()/2.0));  if (left >= x2)    return false;  if (test)    return true;  double newW = x2 - left;  double newX = (double)(left + newW/2.0);  SetSize(newW, GetHeight());  wxClientDC dc(GetCanvas());  GetCanvas()->PrepareDC(dc);  Move(dc, newX, GetY());  return true;}

void PCB_BASE_FRAME::SetPrevGrid(){    EDA_DRAW_FRAME::SetPrevGrid();    if( m_gridSelectBox )    {        wxCommandEvent cmd( wxEVT_CHOICE );        cmd.SetEventObject( this );        OnSelectGrid( cmd );    }    else        GetCanvas()->Refresh();}

void CGUIContext::Clear(){	Console = 0;	TitleLabels = 0;	VolumeControl = 0;	TerrainControl = 0;	GlyphControl = 0;	SceneControl = 0;	ControlPanel = 0;	Manager->RemoveAllWidgets();	GetCanvas()->RemoveAllChildren();}

void GTKWindow::PanelStateChanged(void){    Rect       oRect;    GdkBitmap *mask;    GetCanvas()->SetNoScreenUpdate(true);    Window::PanelStateChanged();    GetCanvas()->GetBackgroundRect(oRect);    mask = ((GTKCanvas *)m_pCanvas)->GetMask();    gdk_threads_enter();    if (mask)        gdk_window_shape_combine_mask(mainWindow->window, mask, 0, 0);    gtk_widget_set_usize(mainWindow, oRect.Width(), oRect.Height());    gdk_threads_leave();    GetCanvas()->SetNoScreenUpdate(false);    ((GTKCanvas *)GetCanvas())->Paint(oRect);}

void wxCompositeShape::SetSize(double w, double h, bool recursive){	SetAttachmentSize(w, h);	double xScale = (double)(w / (wxMax(1.0, GetWidth())));	double yScale = (double)(h / (wxMax(1.0, GetHeight())));	m_width = w;	m_height = h;	if (!recursive) return;	wxNode *node = m_children.GetFirst();	wxClientDC dc(GetCanvas());	GetCanvas()->PrepareDC(dc);	double xBound, yBound;	while (node)	{		wxShape *object = (wxShape *)node->GetData();		// Scale the position first		double newX = (double)(((object->GetX() - GetX()) * xScale) + GetX());		double newY = (double)(((object->GetY() - GetY()) * yScale) + GetY());		object->Show(FALSE);		object->Move(newX, newY);		object->Show(TRUE);		// Now set the scaled size		object->GetBoundingBoxMin(&xBound, &yBound);		object->SetSize(object->GetFixedWidth() ? xBound : xScale * xBound,		                object->GetFixedHeight() ? yBound : yScale * yBound);		node = node->GetNext();	}	SetDefaultRegionSize();}

void ComboBox::Open(){    if (!_menu)    {        return;    }    _menu->SetParent(GetCanvas());    _menu->SetHidden(false);    _menu->BringToFront();    Gwen::Point point = LocalPositionToCanvas(Gwen::Point(0, 0));    _menu->SetBounds(Gwen::Rectangle(point._x, point._y + Height(), Width(), _menu->Height()));}

voidTGUIReinforcementView::Paint(){    if( animationCounter != lastAnimationCounter )    {        if( animationCounter < numAnimationFrames )            animationBitmap = animFrames[ animationCounter ];        else            animationBitmap = NULL;        lastAnimationCounter = animationCounter;    }    if( animationBitmap != NULL )        GetCanvas()->Draw( animTRect.Left, animTRect.Top, animationBitmap );}

void MyFrame::OnSetFaceName(wxCommandEvent& WXUNUSED(event)){    wxString facename = GetCanvas()->GetTextFont().GetFaceName();    wxString newFaceName = wxGetTextFromUser(            wxT("Here you can edit current font face name."),            wxT("Input font facename"), facename,            this);    if (newFaceName.IsEmpty())        return;     // user clicked "Cancel" - do nothing    wxFont font(GetCanvas()->GetTextFont());    if (font.SetFaceName(newFaceName))      // change facename only    {        wxASSERT_MSG(font.IsOk(), wxT("The font should now be valid"));        DoChangeFont(font);    }    else    {        wxASSERT_MSG(!font.IsOk(), wxT("The font should now be invalid"));        wxMessageBox(wxT("There is no font with such face name..."),                     wxT("Invalid face name"), wxOK|wxICON_ERROR, this);    }}

// Control points ('handles') redirect control to the actual shape, to make it easier// to override sizing behaviour.void wxPolygonShape::OnSizingDragLeft(wxControlPoint *pt, bool WXUNUSED(draw), double x, double y, int WXUNUSED(keys), int WXUNUSED(attachment)){	wxPolygonControlPoint *ppt = (wxPolygonControlPoint *) pt;	wxClientDC dc(GetCanvas());	GetCanvas()->PrepareDC(dc);	dc.SetLogicalFunction(OGLRBLF);	wxPen dottedPen(wxColour(0, 0, 0), 1, wxDOT);	dc.SetPen(dottedPen);	dc.SetBrush((* wxTRANSPARENT_BRUSH));#if 0 // keys & KEY_CTRL)	{		// TODO: mend this code. Currently we rely on altering the		// actual points, but we should assume we're not, as per		// the normal sizing case.		m_canvas->Snap(&x, &y);		// Move point		ppt->m_polygonVertex->x = x - this->GetX();		ppt->m_polygonVertex->y = y - this->GetY();		ppt->SetX(x);		ppt->SetY(y);		((wxPolygonShape *)this)->CalculateBoundingBox();		((wxPolygonShape *)this)->CalculatePolygonCentre();	}#else	{		ppt->CalculateNewSize(x, y);	}#endif	this->GetEventHandler()->OnDrawOutline(dc, this->GetX(), this->GetY(),	                                       ppt->GetNewSize().x, ppt->GetNewSize().y);}

Error GTKWindow::GetWindowPosition(Rect &oWindowRect) {    if (!mainWindow->window)        return kError_NoErr;    gdk_threads_enter();    gdk_window_get_position(mainWindow->window, &oWindowRect.x1,                             &oWindowRect.y1);    gdk_threads_leave();    Rect oRect;    if (GetCanvas()) {        GetCanvas()->GetBackgroundRect(oRect);           oWindowRect.x2 = oWindowRect.x1 + oRect.Width();        oWindowRect.y2 = oWindowRect.y1 + oRect.Height();    }    else {        oWindowRect.x2 = oWindowRect.x1;        oWindowRect.y2 = oWindowRect.y1;    }    return kError_NoErr;}

void Menu::Layout(Skin::Base* skin){    // Call the base class.    ScrollControl::Layout(skin);    int children_height = 0;    for (auto i = _inner_panel->GetChildren().begin(); i != _inner_panel->GetChildren().end(); ++i)    {        Base* child = (*i);        assert(child != nullptr);        if (child != nullptr)        {            children_height += child->Height();        }    }    if (Y() + children_height > GetCanvas()->Height())    {        children_height = GetCanvas()->Height() - Y();    }    SetSize(Width(), children_height);}

void SCH_EDIT_FRAME::DeleteAnnotation( bool aCurrentSheetOnly ){    if( aCurrentSheetOnly )    {        m_CurrentSheet->Last()->ClearAnnotation();    }    else    {        m_CurrentSheet->Last()->GetRootSheet()->ClearAnnotation( true );    }    // Update the references for the sheet that is currently being displayed.    m_CurrentSheet->Last()->UpdateAllScreenReferences();    GetCanvas()->Refresh();    OnModify();}

void LIB_VIEW_FRAME::OnCloseWindow( wxCloseEvent& Event ){    GetCanvas()->StopDrawing();    if( !IsModal() )    {        Destroy();    }    else if( !IsDismissed() )    {        // only dismiss modal frame if not already dismissed.        DismissModal( false );        // Modal frame will be destroyed by the calling function.    }}

void PCB_BASE_FRAME::SetFastGrid2(){    if( m_FastGrid2 >= (int)GetScreen()->GetGridCount() )        return;    int cmdId = GetScreen()->GetGrids()[m_FastGrid2].m_CmdId;    SetPresetGrid( cmdId - ID_POPUP_GRID_LEVEL_1000 );    if( m_gridSelectBox )    {        wxCommandEvent cmd( wxEVT_CHOICE );        cmd.SetEventObject( this );        OnSelectGrid( cmd );    }    else        GetCanvas()->Refresh();}

void FieldStringEditor::do_xselection_paste(const Event& e) {  XDisplay* disp = GetWorld()->display()->rep()->display_;  unsigned int win = GetCanvas()->rep()->window_->rep()->xwindow_;  Atom target_property = XInternAtom(disp, "PASTESTRING", false);  Atom actual_atom;  int actual_format;  unsigned long ret_length, ret_remaining;  unsigned char* data;  int ret=XGetWindowProperty(disp, win, target_property,			     0L, BUFSIZ, false, XA_STRING,			     &actual_atom, &actual_format, &ret_length,			     &ret_remaining, &data);  if (ret == Success && data) {    InsertText((char*) data, strlen((char*)data));    XFree(data);  }}