/// <summary>
/// Decodes the current line DAD.
/// </summary>
private void SetLine()
{
// Define the line as the active feature
m_Feature = (Ntx.Feature)m_Line;
// Define characteristics common to all features
this.SetFeature();
// Initialize the simple stuff
m_Line.IsTopologicalArc = this.IsArc;
m_Line.IsCurve = this.IsCurve;
if (m_Line.IsCurve)
{
m_Line.Radius = this.Radius;
m_Line.Center = this.Center;
m_Line.BC = this.BC;
m_Line.EC = this.EC;
}
else
{
m_Line.Radius = 0.0;
m_Line.Center = null;
m_Line.BC = null;
m_Line.EC = null;
}
// Load data for the line, chaining through the DADs if required.
m_NumPosition = 0;
bool islinked = this.LoadPositions();
while (islinked)
{
islinked = this.LoadPositions();
}
m_Line.NumPosition = m_NumPosition;
m_Line.Positions = m_Positions;
}
/// <summary>
/// Reads the next feature from the file.
/// </summary>
/// <returns>The next feature (null at end of file).</returns>
Feature GetNext()
{
// Deactivate any feature previously found
m_Feature = null;
// While we haven't got to something we can understand do
while (m_Desc[0]==0)
{
// Read the next super-descriptor or descriptor
ReadArray(m_Desc);
// Return if no more data in the file
if ((uint)m_Desc[0]==ECC)
return null;
// If we have a super-descriptor, remember it, and read
// the graphics descriptor that follows. Otherwise
// remember that there was no super-descriptor.
if (m_Desc[Pointers.PDCODE] > OFFSUD)
{
Array.Copy(m_Desc, m_SuperDesc, DESL);
ReadArray(m_Desc);
}
else
m_SuperDesc[0] = 0;
// Read the data array as well
Read(m_Desc[Pointers.PDLNST]-DESL, m_Data);
// Exit loop if the descriptor is something we can parse
if ( m_Desc[Pointers.PDCODE] == (int)Ntx.DataType.DeltaLine ||
m_Desc[Pointers.PDCODE] == (int)Ntx.DataType.Line ||
m_Desc[Pointers.PDCODE] == (int)Ntx.DataType.Name ||
m_Desc[Pointers.PDCODE] == (int)Ntx.DataType.Symbol)
break;
m_Desc[0] = 0;
}
// We now have a graphics descriptor, a data array, and
// possibly a super-descriptor record. Parse the data.
switch (m_Desc[Pointers.PDCODE])
{
case (int)Ntx.DataType.DeltaLine:
case (int)Ntx.DataType.Line:
{
SetLine();
break;
}
case (int)Ntx.DataType.Name:
{
SetName();
break;
}
case (int)Ntx.DataType.Symbol:
{
SetSymbol();
break;
}
}
// If we just generated a symbol, and there are more symbols in
// the DAD, don't de-activate the DAD. Otherwise de-activate by
// setting the string length to zero. Note that the symbol
// constructor adjusts the string length to account for the
// fact that the symbol has been returned as a feature.
if ( m_Desc[Pointers.PDCODE] == (int)Ntx.DataType.Symbol &&
m_Desc[Pointers.PDLNST] >= (DESL+m_Data[Pointers.PQHLEN]+m_Data[Pointers.PQRLEN]))
{
// do nothing
}
else
m_Desc[0] = 0;
// Return the feature we created.
Debug.Assert(m_Feature!=null);
return m_Feature;
}
/// <summary>
/// Decodes the current symbol DAD.
/// </summary>
private void SetSymbol()
{
// Define the symbol as the active feature
m_Feature = (Feature)m_Symbol;
// Define characteristics common to all features
this.SetFeature();
// The location always refers to the first data group
m_Symbol.Position = this.FirstPosition;
// Check if this symbol is a topological node
m_Symbol.IsNode = this.IsNode;
// If there are actually more symbols in the DAD, shift them back
this.RemoveFirstGroup();
}
/// <summary>
/// Default constructor
/// </summary>
public File()
{
m_FileSpec = String.Empty;
m_File = null;
m_NextWord = 0;
m_Feature = null;
m_Desc[0] = 0;
m_SuperDesc[0] = 0;
m_Data[0] = 0;
m_BytesRead = 0;
m_NumPosition = 0;
}
/// <summary>
/// Decodes the current name DAD.
/// </summary>
private void SetName()
{
// Define the name as the active feature
m_Feature = (Feature)m_Name;
// Define characteristics common to all features
this.SetFeature();
m_Name.RefPosition = this.RefPosition;
m_Name.Text = this.NameText;
m_Name.IsLabel = this.IsLabel;
m_Name.Height = this.Height;
//m_Name.Rotation = this.FirstRotation;
// Hold the position of each character in the file's position list.
int nchar = m_Name.Count;
m_NumPosition = 0;
// Names SHOULDN'T be linked, but let's see what happens if they are ...
bool islinked = this.LoadPositions();
while (islinked)
{
islinked = this.LoadPositions();
}
m_Name.Positions = m_Positions;
}
