private void UpdateMeshInfoBox(int itemIndex)
{
if (itemIndex < 0)
{
// nothing selected
ResetMeshInfoLabels();
}
else
{
MeshInfoBox.Text = String.Format("Mesh Info for {0}", _meshInfoList[itemIndex].MeshName);
MeshInfo meshInfo = _meshInfoList[itemIndex];
lblQuadFaceCount.Text = String.Format("{0} quadrilateral faces", meshInfo.QuadFaceCount);
lblTriangularFaceCount.Text = String.Format("{0} triangular faces", meshInfo.TriangularFaceCount);
lblVertexCount.Text = String.Format("{0} vertices", meshInfo.VertexCount);
lblNormalCount.Text = String.Format("{0} normals", meshInfo.NormalCount);
lblTextureCoordCount.Text = String.Format("{0} uv coordinates", meshInfo.UVCoordCount);
}
}
// This event handler is where the (potentially) time-consuming work is done.
static void LoadFile(object sender, DoWorkEventArgs e)
{
int currentMesh = 1;
_bw.ReportProgress(currentMesh);
string meshName = "";
string[] fileLines = null;
int index = 0;
// require at least "g mesh[\n]v x y z[\n]v a b c[\n]v u v w[\n]f 0 1 2"
const int MinFileLines = 5;
// 3-state FSM: 1) reading file; 2) scanning for line with "g [meshname]"; 3) loading mesh data
int state = 0;
while (state < 3)
{
_bw.ReportProgress(currentMesh);
// the reason for using the state machine loop approach is
// to provide a convenient place to put this check for cancellation
if (_bw.CancellationPending)
{
e.Cancel = true;
break;
}
else
{
switch (state)
{
case 0:
// read file data
fileLines = File.ReadAllLines(_objFilePath);
if (fileLines.Length < MinFileLines)
{
// notify user about error condition
MessageBox.Show("Error: file format not recognized");
Cancel(e);
return;
}
++state;
break;
case 1:
// scan for 1st occurrence of "g"
while (index < fileLines.Length)
{
string[] parts = fileLines[index++].Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
if (parts.Length > 0)
{
if (parts[0] == "g")
{
if (parts.Length > 1)
{
meshName = parts[1];
}
else
{
meshName = "[unnamed]";
}
_meshInfoList = new List <MeshInfo>();
++state;
break;
}
}
}
if (index == fileLines.Length)
{
// notify user of error condition if no "g" found in the file
MessageBox.Show("Error: no named mesh (group) found in file");
Cancel(e);
return;
}
break;
case 2:
// load mesh data
MeshInfo meshInfo = new MeshInfo
{
MeshName = meshName
};
// NOTE side effect of processing the current mesh:
// if another mesh ("g") encountered, returns its name
// else returns a special "flag" name
meshName = meshInfo.LoadFileLines(fileLines, ref index);
_meshInfoList.Add(meshInfo);
if (MeshInfo.MeshEndFlag == meshName)
{
// all done loading
++state;
}
else
{
// there is another mesh to load, we'll get it on the
// next pass through the while loop (remaining in this
// same FSM state 2)
++currentMesh;
}
break;
default:
// "should never happen"
// for a professional utility I would log an error message here
break;
}
}
}
}
