/// TODO: CairoExtensions.CachedDraw seems not to work correctly for me.
public static void CachedDraw(Cairo.Context self, ref SurfaceWrapper surface, Gdk.Rectangle region, object parameters = null, float opacity = 1.0f, Action <Cairo.Context, float> draw = null, double?forceScale = null)
{
double displayScale = forceScale.HasValue ? forceScale.Value : QuartzSurface.GetRetinaScale(self);
int targetWidth = (int)(region.Width * displayScale);
int targetHeight = (int)(region.Height * displayScale);
bool redraw = false;
if (surface == null || surface.Width != targetWidth || surface.Height != targetHeight)
{
if (surface != null)
{
surface.Dispose();
}
surface = new SurfaceWrapper(self, targetWidth, targetHeight);
redraw = true;
}
else if ((surface.Data == null && parameters != null) || (surface.Data != null && !surface.Data.Equals(parameters)))
{
redraw = true;
}
if (redraw)
{
surface.Data = parameters;
using (var context = new Cairo.Context(surface.Surface)) {
draw(context, 1.0f);
}
}
self.SetSourceSurface(surface.Surface, 0, 0);
self.Paint();
}
void UpdateScale()
{
if (MonoDevelop.Core.Platform.IsMac)
{
using (var similar = Gdk.CairoHelper.Create(owner.GdkWindow)) {
Scale = QuartzSurface.GetRetinaScale(similar);
}
}
else
{
Scale = 1;
}
}
