/// <summary>
/// BeforeRender - Make sure we have a Graphics object to render to.
/// If we don't have one, then create one to match the SvgWindow's
/// physical dimensions.
/// </summary>
private void RendererBeforeRender()
{
// Testing for null here allows "advanced" developers to create their own Graphics object for rendering
if (graphics == null)
{
// Get the current SVGWindow's width and height
int innerWidth = (int)window.InnerWidth;
int innerHeight = (int)window.InnerHeight;
// Make sure we have an actual area to render to
if (innerWidth > 0 && innerHeight > 0)
{
// See if we already have a rasterImage that matches the current SVGWindow dimensions
if (rasterImage == null || rasterImage.Width != innerWidth || rasterImage.Height != innerHeight)
{
// Nope, so create one
if (rasterImage != null)
{
rasterImage.Dispose();
rasterImage = null;
}
rasterImage = new Bitmap(innerWidth, innerHeight);
}
// Maybe we are only repainting an invalidated section
if (invalidRect != SvgRectF.Empty)
{
// TODO: Worry about pan...
if (invalidRect.X < 0)
{
invalidRect.X = 0;
}
if (invalidRect.Y < 0)
{
invalidRect.Y = 0;
}
if (invalidRect.Right > innerWidth)
{
invalidRect.Width = innerWidth - invalidRect.X;
}
if (invalidRect.Bottom > innerHeight)
{
invalidRect.Height = innerHeight - invalidRect.Y;
}
if (invalidatedRasterImage == null || invalidatedRasterImage.Width < invalidRect.Right ||
invalidatedRasterImage.Height < invalidRect.Bottom)
{
// Nope, so create one
if (invalidatedRasterImage != null)
{
invalidatedRasterImage.Dispose();
invalidatedRasterImage = null;
}
invalidatedRasterImage = new Bitmap((int)invalidRect.Right, (int)invalidRect.Bottom);
}
// Make a GraphicsWrapper object from the regionRasterImage and clear it to the background color
graphics = GdiGraphicsWrapper.FromImage(invalidatedRasterImage, false);
graphics.Clear(backColor);
}
else
{
// Make a GraphicsWrapper object from the rasterImage and clear it to the background color
graphics = GdiGraphicsWrapper.FromImage(rasterImage, false);
graphics.Clear(backColor);
}
}
}
}
public static GdiGraphics Create(Image image, bool isStatic)
{
return(GdiGraphicsWrapper.FromImage(image, isStatic));
}