void UpdateScroll()
{
GDI.SCROLLINFO si = new GDI.SCROLLINFO();
si.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(typeof(GDI.SCROLLINFO));
si.fMask = (int)(GDI.ScrollInfoMask.SIF_RANGE | GDI.ScrollInfoMask.SIF_POS | GDI.ScrollInfoMask.SIF_PAGE);
double xpc = (m_view.Left - m_physExtents.Left) / m_physExtents.Width;
double wpc = m_view.Width / m_physExtents.Width;
si.nPos = (int)(xpc * ScrollScale);
si.nMin = 0;
si.nMax = (int)ScrollScale;
si.nPage = (int)(wpc * ScrollScale);
GDI.SetScrollInfo(Handle, (int)GDI.ScrollBarDirection.SB_HORZ, ref si, true);
double ypc = (m_view.Top - m_physExtents.Top) / m_physExtents.Height;
double hpc = m_view.Height / m_physExtents.Height;
si.nPos = (int)(ypc * ScrollScale);
si.nMin = 0;
si.nMax = (int)ScrollScale;
si.nPage = (int)(hpc * ScrollScale);
GDI.SetScrollInfo(Handle, (int)GDI.ScrollBarDirection.SB_VERT, ref si, true);
}
void UpdateScroll()
{
GDI.SCROLLINFO si = new GDI.SCROLLINFO();
si.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(typeof(GDI.SCROLLINFO));
si.fMask = (int)(GDI.ScrollInfoMask.SIF_RANGE | GDI.ScrollInfoMask.SIF_POS | GDI.ScrollInfoMask.SIF_PAGE);
si.nPos = (int)(m_view.Left - m_physExtents.Left);
si.nMin = 0;
si.nMax = (int)m_physExtents.Size.X;
si.nPage = (int)m_view.Width;
GDI.SetScrollInfo(Handle, (int)GDI.ScrollBarDirection.SB_HORZ, ref si, true);
si.nPos = (int)(m_view.Top - m_physExtents.Top);
si.nMin = 0;
si.nMax = (int)m_physExtents.Size.Y;
si.nPage = (int)m_view.Height;
GDI.SetScrollInfo(Handle, (int)GDI.ScrollBarDirection.SB_VERT, ref si, true);
}
protected void OnScroll(ScrollEventArgs se)
{
bool hasViewChanged = false;
if (se.ScrollOrientation == ScrollOrientation.HorizontalScroll)
{
GDI.SCROLLINFO si = new GDI.SCROLLINFO();
si.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(typeof(GDI.SCROLLINFO));
si.fMask = (int)(GDI.ScrollInfoMask.SIF_TRACKPOS | GDI.ScrollInfoMask.SIF_PAGE | GDI.ScrollInfoMask.SIF_POS);
GDI.GetScrollInfo(Handle, (int)GDI.ScrollBarDirection.SB_HORZ, ref si);
switch (se.Type)
{
case ScrollEventType.LargeDecrement:
m_view = new RectD(m_view.Left - m_view.Width, m_view.Top, m_view.Right - m_view.Width, m_view.Bottom);
break;
case ScrollEventType.LargeIncrement:
m_view = new RectD(m_view.Left + m_view.Width, m_view.Top, m_view.Right + m_view.Width, m_view.Bottom);
break;
case ScrollEventType.SmallDecrement:
m_view = new RectD(m_view.Left - m_view.Width * 0.1f, m_view.Top, m_view.Right - m_view.Width * 0.1f, m_view.Bottom);
break;
case ScrollEventType.SmallIncrement:
m_view = new RectD(m_view.Left + m_view.Width * 0.1f, m_view.Top, m_view.Right + m_view.Width * 0.1f, m_view.Bottom);
break;
case ScrollEventType.ThumbTrack:
{
double tp = si.nTrackPos / ScrollScale * m_physExtents.Width + m_physExtents.Left;
m_view = new RectD(tp, m_view.Top, tp + m_view.Width, m_view.Bottom);
}
break;
}
ClampView();
UpdateScroll();
Invalidate();
hasViewChanged = true;
}
else if (se.ScrollOrientation == ScrollOrientation.VerticalScroll)
{
GDI.SCROLLINFO si = new GDI.SCROLLINFO();
si.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(typeof(GDI.SCROLLINFO));
si.fMask = (int)(GDI.ScrollInfoMask.SIF_TRACKPOS | GDI.ScrollInfoMask.SIF_PAGE | GDI.ScrollInfoMask.SIF_POS);
GDI.GetScrollInfo(Handle, (int)GDI.ScrollBarDirection.SB_VERT, ref si);
switch (se.Type)
{
case ScrollEventType.LargeDecrement:
m_view = new RectD(m_view.Left, m_view.Top - m_view.Height, m_view.Right, m_view.Bottom - m_view.Height);
break;
case ScrollEventType.LargeIncrement:
m_view = new RectD(m_view.Left, m_view.Top + m_view.Height, m_view.Right, m_view.Bottom + m_view.Height);
break;
case ScrollEventType.SmallDecrement:
m_view = new RectD(m_view.Left, m_view.Top - m_view.Height * 0.1f, m_view.Right, m_view.Bottom - m_view.Height * 0.1f);
break;
case ScrollEventType.SmallIncrement:
m_view = new RectD(m_view.Left, m_view.Top + m_view.Height * 0.1f, m_view.Right, m_view.Bottom + m_view.Height * 0.1f);
break;
case ScrollEventType.ThumbTrack:
{
double tp = si.nTrackPos / ScrollScale * m_physExtents.Height + m_physExtents.Top;
m_view = new RectD(m_view.Left, tp, m_view.Right, tp + m_view.Height);
}
break;
}
ClampView();
UpdateScroll();
Invalidate();
hasViewChanged = true;
}
if (hasViewChanged)
{
OnViewChanged();
}
}
