/// <summary>
/// Draw the background image of the given box in the given rectangle.<br/>
/// Handle background-repeat and background-position values.
/// </summary>
/// <param name="g">the device to draw into</param>
/// <param name="box">the box to draw its background image</param>
/// <param name="imageLoadHandler">the handler that loads image to draw</param>
/// <param name="rectangle">the rectangle to draw image in</param>
public static void DrawBackgroundImage(IGraphics g, CssBox box, ImageLoadHandler imageLoadHandler,
RectangleF rectangle)
{
// image size depends if specific rectangle given in image loader
var imgSize =
new Size(
imageLoadHandler.Rectangle == Rectangle.Empty
? imageLoadHandler.Image.Width
: imageLoadHandler.Rectangle.Width,
imageLoadHandler.Rectangle == Rectangle.Empty
? imageLoadHandler.Image.Height
: imageLoadHandler.Rectangle.Height);
// get the location by BackgroundPosition value
Point location = GetLocation(box.BackgroundPosition, rectangle, imgSize);
Rectangle srcRect = imageLoadHandler.Rectangle == Rectangle.Empty
? new Rectangle(0, 0, imgSize.Width, imgSize.Height)
: new Rectangle(imageLoadHandler.Rectangle.Left, imageLoadHandler.Rectangle.Top,
imgSize.Width, imgSize.Height);
// initial image destination rectangle
var destRect = new Rectangle(location, imgSize);
// need to clip so repeated image will be cut on rectangle
RectangleF prevClip = g.GetClip();
RectangleF lRectangle = rectangle;
lRectangle.Intersect(prevClip);
g.SetClip(lRectangle);
switch (box.BackgroundRepeat)
{
case "no-repeat":
g.DrawImage(imageLoadHandler.Image, destRect, srcRect);
break;
case "repeat-x":
DrawRepeatX(g, imageLoadHandler, rectangle, srcRect, destRect, imgSize);
break;
case "repeat-y":
DrawRepeatY(g, imageLoadHandler, rectangle, srcRect, destRect, imgSize);
break;
default:
DrawRepeat(g, imageLoadHandler, rectangle, srcRect, destRect, imgSize);
break;
}
g.SetClip(prevClip);
}
/// <summary>
/// Draw the background image at the required location repeating it over the Y axis.<br/>
/// Adjust location to top if starting location doesn't include all the range (adjusted to center or bottom).
/// </summary>
private static void DrawRepeatY(IGraphics g, ImageLoadHandler imageLoadHandler, RectangleF rectangle,
Rectangle srcRect, Rectangle destRect, Size imgSize)
{
while (destRect.Y > rectangle.Y)
{
destRect.Y -= imgSize.Height;
}
using (var brush = new TextureBrush(imageLoadHandler.Image, srcRect))
{
brush.TranslateTransform(destRect.X, destRect.Y);
g.FillRectangle(brush, destRect.X, rectangle.Y, srcRect.Width, rectangle.Height);
}
}
