private void onPenData(wgssSTU.IPenData penData) // Process incoming pen data
{
Point pt = tabletToScreen(penData);
int btn = 0; // will be +ve if the pen is over a button.
{
for (int i = 0; i < m_btns.Length; ++i)
{
if (m_btns[i].Bounds.Contains(pt))
{
btn = i + 1;
break;
}
}
}
bool isDown = (penData.sw != 0);
// This code uses a model of four states the pen can be in:
// down or up, and whether this is the first sample of that state.
if (isDown)
{
if (m_isDown == 0)
{
// transition to down
if (btn > 0)
{
// We have put the pen down on a button.
// Track the pen without inking on the client.
m_isDown = btn;
}
else
{
// We have put the pen down somewhere else.
// Treat it as part of the signature.
m_isDown = -1;
}
}
else
{
// already down, keep doing what we're doing!
}
// draw
if (m_penData.Count != 0 && m_isDown == -1)
{
// Draw a line from the previous down point to this down point.
// This is the simplist thing you can do; a more sophisticated program
// can perform higher quality rendering than this!
Graphics gfx = this.CreateGraphics();
gfx.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
gfx.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
gfx.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
gfx.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
wgssSTU.IPenData prevPenData = m_penData[m_penData.Count - 1];
PointF prev = tabletToClient(prevPenData);
gfx.DrawLine(m_penInk, prev, tabletToClient(penData));
gfx.Dispose();
}
// The pen is down, store it for use later.
if (m_isDown == -1)
{
m_penData.Add(penData);
}
}
else
{
if (m_isDown != 0)
{
// transition to up
if (btn > 0)
{
// The pen is over a button
if (btn == m_isDown)
{
// The pen was pressed down over the same button as is was lifted now.
// Consider that as a click!
m_btns[btn - 1].PerformClick();
}
}
m_isDown = 0;
}
else
{
// still up
}
// Add up data once we have collected some down data.
if (m_penData != null)
{
if (m_penData.Count != 0)
{
m_penData.Add(penData);
}
}
}
}
// As per the file comment, there are three coordinate systems to deal with.
// To help understand, we have left the calculations in place rather than optimise them.
private PointF tabletToClient(wgssSTU.IPenData penData)
{
// Client means the Windows Form coordinates.
return(new PointF((float)penData.x * this.ClientSize.Width / m_capability.tabletMaxX, (float)penData.y * this.ClientSize.Height / m_capability.tabletMaxY));
}
private Point tabletToScreen(wgssSTU.IPenData penData)
{
// Screen means LCD screen of the tablet.
return(Point.Round(new PointF((float)penData.x * m_capability.screenWidth / m_capability.tabletMaxX, (float)penData.y * m_capability.screenHeight / m_capability.tabletMaxY)));
}
private Point tabletToScreen(wgssSTU.IPenData penData, Rectangle customResolution)
{
// Screen means LCD screen of the tablet.
return(Point.Round(new PointF(((float)customResolution.X) + ((float)penData.x * (customResolution.Width - customResolution.X) / m_capability.tabletMaxX), ((float)customResolution.Y) + ((float)penData.y * (customResolution.Height - customResolution.Y) / m_capability.tabletMaxY))));
}
