private RectangleF GetRandomImageRect(Database db, Rectangle screenRect, float imgWidth, float imgHeight)
{
var retries = k_randomRectRetries;
var bestRect = new RectangleF(0.0f, 0.0f, 0.0f, 0.0f);
var bestOverlap = -1.0f;
var screenRectF = screenRect;
var oldRects = _theme.ImageRectHistory.ToArray();
while (retries-- > 0)
{
var rect = new RectangleF(
(float)(_rand.NextDouble() * (screenRect.Width - imgWidth)) + screenRect.X,
(float)(_rand.NextDouble() * (screenRect.Height - imgHeight)) + screenRect.Y,
imgWidth, imgHeight);
var overlap = 0.0f;
for (int i = 0; i < oldRects.Length; i++)
{
var ratio = (double)(i + 1) / (double)oldRects.Length;
var importance = Math.Pow(ratio, Math.E);
overlap += oldRects[i].IntersectArea(rect) * (float)importance;
}
if (overlap < bestOverlap || bestOverlap < 0)
{
bestRect = rect;
bestOverlap = overlap;
}
}
_theme.AddImageRectHistory(db, bestRect, _screenRects.Count);
return(bestRect);
}