// Render to a bitmap and check against the saved version.
internal void CheckHighlightBitmap(CourseObj courseobj, string basename)
{
Bitmap bmNew = RenderToBitmap(courseobj, Color.White);
Bitmap bmEraseBrush = (Bitmap) bmNew.Clone();
Bitmap bmHighlighted = (Bitmap) bmNew.Clone();
Matrix matrix = GetTransform(bmNew.Size);
using (Graphics g = Graphics.FromImage(bmHighlighted)) {
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SingleBitPerPixel;
courseobj.DrawHighlight(g, matrix);
}
Bitmap bmErased = (Bitmap) bmHighlighted.Clone();
TestUtil.CheckBitmapsBase(bmHighlighted, "coursesymbols\\" + basename);
using (TextureBrush eraseBrush = new TextureBrush(bmEraseBrush))
using (Graphics g = Graphics.FromImage(bmErased)) {
g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SingleBitPerPixel;
courseobj.EraseHighlight(g, matrix, eraseBrush);
}
Bitmap bmDiff;
bmDiff = TestUtil.CompareBitmaps(bmNew, bmErased, Color.LightPink, Color.Transparent, 0);
if (bmDiff != null)
bmDiff.Save(TestUtil.GetTestFile("coursesymbols\\" + basename + "_diff.png"), ImageFormat.Png);
Assert.IsNull(bmDiff, "after erase does not match with before highlight");
bmEraseBrush.Dispose();
}
