It could be a clipping problem actually, since ShapeNodes are clipped to their Shape outline. Try custom drawing them, or overriding the Draw method to avoid clipping:
private void Form1_Load(object sender, System.EventArgs e)
var image = (Bitmap)Image.FromFile("rect_frame.png");
image.SetResolution(196, 196);
diagram.MeasureUnit = GraphicsUnit.Pixel;
for (int i = 0; i < 50; i+= 5)
{
var node = diagram.Factory.CreateShapeNode(i, i * 2, 5, 5);
node.Image = image;
node.CustomDraw = CustomDraw.Full;
node.ResizeToFitImage();
}
}
private void diagram_DrawNode(object sender, DrawNodeEventArgs e)
{
var shape = e.Node as ShapeNode;
if (shape != null)
Utilities.DrawImage(e.Graphics, shape.Image, shape.Bounds, ImageAlign.Stretch);
}
The nodes above show missing lines when not custom drawn but have Transparent enabled, which probably happen due to some imprecision in clipping regions. They are drawn fine if only drawing stretched images with custom drawing.
We also have a ClipImage property in the WPF version that controls whether images are clipped by the shape, we'll implement it in Windows forms too for next release.
I hope that helps,
Stoyan