private void InfiniteReader_MouseWheel(object sender, MouseEventArgs e)
{
bool zooming = false;
if (RawInput.IsPressed(VirtualKeys.Control))
{
zooming = true;
if (e.Delta > 0)
{
scale *= 1.41f;
}
else
{
scale /= 1.41f;
}
this.Invalidate();
}
int movement = -e.Delta;
float maximumScroll = float.MaxValue;
//Don't allow scrolling if the last visible page is the last page available
if (movement > 0 || zooming)
{
if (provider.IsLastPage(lastVisiblePage))
{
maximumScroll = GetFitDimensions(CurrentPage).Height;
for (int i = buffer + 1; i < loadedPages.Count; i++)
{
if (loadedPages[i] == null)
{
break;
}
maximumScroll += GetFitDimensions(loadedPages[i]).Height;
}
maximumScroll -= Height;
}
}
else if (movement < 0)
{
if (provider.IsFirstPage(CurrentPage))
{
scrollOffset = Math.Max(0, scrollOffset + movement);
this.Invalidate();
return;
}
}
if (zooming)
{
return;
}
scrollOffset = (int)(Math.Min(maximumScroll, scrollOffset + movement));
RefetchPages();
int scaledPageHeight = GetFitDimensions(CurrentPage).Height;
if (scrollOffset > scaledPageHeight)
{
while (scrollOffset > scaledPageHeight)
{
MoveToNextPage();
scrollOffset = scrollOffset - scaledPageHeight;
scaledPageHeight = GetFitDimensions(CurrentPage).Height;
}
}
else if (scrollOffset < 0)
{
while (scrollOffset < 0)
{
MoveToPreviousPage();
scrollOffset += GetFitDimensions(CurrentPage).Height;
}
}
this.Invalidate();
}