private async void Image_MouseUp(object sender, MouseButtonEventArgs e)
{
if (!DrawSelectionBox)
{
return;
}
// Release the mouse capture and stop tracking it.
DrawSelectionBox = false;
OuterGrid.ReleaseMouseCapture();
// Hide the drag selection box.
SelectionBox.Visibility = Visibility.Collapsed;
var l = RenderImage.TranslatePoint(new Point(0, 0), OuterGrid);
var mouseUpPos = e.GetPosition(OuterGrid);
if (mouseUpPos.X < l.X || mouseUpPos.X > l.X + RenderImage.ActualWidth)
{
return;
}
if (!(DataContext is MandelbrotViewModel dc) || !dc.CanRender())
{
return;
}
var topLeft = SelectionBox.TranslatePoint(new Point(0, 0), RenderImage);
var downRight = topLeft;
downRight.X += SelectionBox.Width;
downRight.Y += SelectionBox.Height;
var oldL = dc.LeftEdge;
var oldR = dc.RightEdge;
var oldD = dc.BottomEdge;
var oldU = dc.UpperEdge;
var newL = oldL + (oldR - oldL) * topLeft.X / dc.CurrentBitmap.PixelWidth *
MandelbrotViewModel.DpiScale;
var newR = oldL + (oldR - oldL) * downRight.X / dc.CurrentBitmap.PixelWidth *
MandelbrotViewModel.DpiScale;
var newU = oldU - (oldU - oldD) * topLeft.Y / dc.CurrentBitmap.PixelHeight *
MandelbrotViewModel.DpiScale;
var newD = oldU - (oldU - oldD) * downRight.Y / dc.CurrentBitmap.PixelHeight *
MandelbrotViewModel.DpiScale;
dc.LeftEdge = newL;
dc.RightEdge = newR;
dc.UpperEdge = newU;
dc.BottomEdge = newD;
await dc.ExecuteRender();
}
private void Image_MouseMove(object sender, MouseEventArgs e)
{
if (DrawSelectionBox)
{
var mousePos = e.GetPosition(OuterGrid);
var l = RenderImage.TranslatePoint(new Point(0, 0), OuterGrid);
if (mousePos.X < l.X || mousePos.X > l.X + RenderImage.ActualWidth)
{
DrawSelectionBox = false;
OuterGrid.ReleaseMouseCapture();
SelectionBox.Visibility = Visibility.Collapsed;
return;
}
if (MouseDownPos.X < mousePos.X)
{
Canvas.SetLeft(SelectionBox, MouseDownPos.X);
SelectionBox.Width = mousePos.X - MouseDownPos.X;
}
else
{
Canvas.SetLeft(SelectionBox, mousePos.X);
SelectionBox.Width = MouseDownPos.X - mousePos.X;
}
if (MouseDownPos.Y < mousePos.Y)
{
Canvas.SetTop(SelectionBox, MouseDownPos.Y);
SelectionBox.Height = mousePos.Y - MouseDownPos.Y;
}
else
{
Canvas.SetTop(SelectionBox, mousePos.Y);
SelectionBox.Height = MouseDownPos.Y - mousePos.Y;
}
}
}