protected sealed override void PaintSurface(DockySurface surface)
{
surface.Clear();
lock (buffers) {
if (slideCounter > 0 && slideCounter < slideSteps)
{
double offset = Allocation.Width * Math.Log(slideCounter) / Math.Log(slideSteps);
if (MovedLeft)
{
ShowBuffer(surface, Page, offset - Allocation.Width);
ShowBuffer(surface, LastPage, offset);
}
else
{
ShowBuffer(surface, Page, Allocation.Width - offset);
ShowBuffer(surface, LastPage, -offset);
}
// fade out the edges during a slide
Gradient linpat = new LinearGradient(0, surface.Height / 2, surface.Width, surface.Height / 2);
linpat.AddColorStop(0, new Color(1, 1, 1, 1));
linpat.AddColorStop(2 * (double)BUTTON_SIZE / surface.Width, new Color(1, 1, 1, 0));
linpat.AddColorStop(1 - 2 * (double)BUTTON_SIZE / surface.Width, new Color(1, 1, 1, 0));
linpat.AddColorStop(1, new Color(1, 1, 1, 1));
surface.Context.Save();
surface.Context.Operator = Operator.Source;
surface.Context.Color = new Cairo.Color(0, 0, 0, 0);
surface.Context.Mask(linpat);
surface.Context.PaintWithAlpha(0);
surface.Context.Restore();
linpat.Destroy();
}
else
{
ShowBuffer(surface, Page, 0);
}
}
// overlay the prev/next arrow buttons
if (buttonBuffer != null && (buttonBuffer.Width != surface.Width || buttonBuffer.Height != surface.Height))
{
ResetButtons();
}
if (buttonBuffer == null)
{
buttonBuffer = new DockySurface(surface.Width, surface.Height, surface);
DrawButtonsBuffer();
}
buttonBuffer.Internal.Show(surface.Context, 0, 0);
}
