protected override bool OnConfigureEvent(EventConfigure ev)
{
if (surface != null)
{
surface.Dispose();
}
surface = ev.Window.CreateSimilarSurface(Cairo.Content.Color, AllocatedWidth, AllocatedHeight);
ClearSurface();
return(true);
}
protected void placeShapes()
{
if (_surface != null)
{
drawingArea.GdkWindow.Clear();
_surface.Dispose();
_surface = null;
}
_min = Vertex.CreateMax();
_max = Vertex.CreateMin();
foreach (AbstractShape shape in _shapes)
{
_min.Minimize(shape.Min);
_max.Maximize(shape.Max);
log("фигура {0} расположена на позиции от {1} до {2}", shape, shape.Min.Literal, shape.Max.Literal);
}
_min -= _lineWidthGap;
_max += _lineWidthGap;
_logicCanvasSize = _max - _min;
log("размер логического холста (с учётом толщины линий) - {0}", _logicCanvasSize.Literal);
_logicCanvasSize *= _prescale;
_surface = new Cairo.ImageSurface(Cairo.Format.Argb32, ( int )_logicCanvasSize.X, ( int )_logicCanvasSize.Y);
using (var surfaceContext = new Cairo.Context(_surface)) {
surfaceContext.SetSourceRGB(1.0, 1.0, 1.0);
surfaceContext.Paint();
surfaceContext.LineWidth = 1.0;
surfaceContext.SetSourceRGB(.0, .0, .0);
surfaceContext.Scale(_prescale, -_prescale);
surfaceContext.Translate(-_min.X, -_max.Y);
if (null != _shapes && 0 < _shapes.Count)
{
foreach (AbstractShape shape in _shapes)
{
shape.Draw(surfaceContext);
surfaceContext.Stroke();
}
}
}
}
// Create a new surface of the appropriate size to store our scribbles
private void ScribbleConfigure(object o, ConfigureEventArgs args)
{
Widget widget = o as Widget;
if (surface != null)
{
surface.Dispose();
}
var allocation = widget.Allocation;
surface = widget.Window.CreateSimilarSurface(Cairo.Content.Color, allocation.Width, allocation.Height);
var cr = new Cairo.Context(surface);
cr.SetSourceRGB(1, 1, 1);
cr.Paint();
((IDisposable)cr).Dispose();
// We've handled the configure event, no need for further processing.
args.RetVal = true;
}
