示例#1
0
        // Colors: Red,Blue,Purple,#006666
        private static IImageProcessingContext DrawWatermark(this IImageProcessingContext context, WatermarkSettings settings)
        {
            var imgSize = context.GetCurrentSize();

            // measure the text size
            var size = TextMeasurer.Measure(settings.Text, new RendererOptions(settings.TextFont));

            //find out how much we need to scale the text to fill the space (up or down)
            var scalingFactor = Math.Min(imgSize.Width / size.Width, imgSize.Height / size.Height) / 3;

            //create a new settings.TextFont
            var scaledFont = new Font(settings.TextFont, scalingFactor * settings.TextFont.Size);
            var center     = settings.Position switch
            {
                WatermarkPosition.Top => new PointF(imgSize.Width / 2, (imgSize.Height / 9)),
                WatermarkPosition.TopLeft => new PointF(imgSize.Width / 2, (imgSize.Height / 9)),
                WatermarkPosition.TopRight => new PointF(imgSize.Width / 2, (imgSize.Height / 9)),
                _ => new PointF(imgSize.Width / 2, imgSize.Height - (imgSize.Height / 9)),
            };

            var textGraphicOptions = new TextGraphicsOptions(true)
            {
                HorizontalAlignment = HorizontalAlignment.Center,
                VerticalAlignment   = VerticalAlignment.Center,
            };

            // Apply Banner
            context.DrawBanner(settings)
            .DrawText(textGraphicOptions, settings.Text, scaledFont, settings.TextColor, center);

            return(context);
        }