/// <summary>
/// Convert <see cref="BeginMode"/> to <see cref="GeometryTypes"/>.
/// </summary>
/// <param name="mode"></param>
/// <returns></returns>
public static GeometryTypes ToGeometryType(this SharpGL.Enumerations.BeginMode mode)
{
GeometryTypes result = GeometryTypes.Point;
switch (mode)
{
case SharpGL.Enumerations.BeginMode.Points:
result = GeometryTypes.Point;
break;
case SharpGL.Enumerations.BeginMode.Lines:
result = GeometryTypes.Line;
break;
case SharpGL.Enumerations.BeginMode.LineLoop:
result = GeometryTypes.Line;
break;
case SharpGL.Enumerations.BeginMode.LineStrip:
result = GeometryTypes.Line;
break;
case SharpGL.Enumerations.BeginMode.Triangles:
result = GeometryTypes.Triangle;
break;
case SharpGL.Enumerations.BeginMode.TriangleString:
result = GeometryTypes.Triangle;
break;
case SharpGL.Enumerations.BeginMode.TriangleFan:
result = GeometryTypes.Triangle;
break;
case SharpGL.Enumerations.BeginMode.Quads:
result = GeometryTypes.Quad;
break;
case SharpGL.Enumerations.BeginMode.QuadStrip:
result = GeometryTypes.Quad;
break;
case SharpGL.Enumerations.BeginMode.Polygon:
result = GeometryTypes.Polygon;
break;
default:
throw new NotImplementedException();
}
return(result);
}
protected PointModel(int pointCount, SharpGL.Enumerations.BeginMode mode)
: base(pointCount, mode)
{
}
/// <summary>
/// Get geometry's count according to specified <paramref name="mode"/>.
/// <para>Returns false if the <paramref name="element"/> is null.</para>
/// </summary>
/// <param name="element"></param>
/// <param name="mode"></param>
/// <param name="count"></param>
/// <returns></returns>
public static bool GetGeometryCount(this IColorCodedPicking element, SharpGL.Enumerations.BeginMode mode, out uint count)
{
bool result = false;
count = uint.MaxValue;
if (element != null)
{
uint vertexCount = element.GetVertexCount();
switch (mode)
{
case SharpGL.Enumerations.BeginMode.Points:
count = vertexCount;
break;
case SharpGL.Enumerations.BeginMode.Lines:
count = vertexCount / 2;
break;
case SharpGL.Enumerations.BeginMode.LineLoop:
count = vertexCount;
break;
case SharpGL.Enumerations.BeginMode.LineStrip:
count = vertexCount - 1;
break;
case SharpGL.Enumerations.BeginMode.Triangles:
count = vertexCount / 3;
break;
case SharpGL.Enumerations.BeginMode.TriangleString:
count = vertexCount - 2;
break;
case SharpGL.Enumerations.BeginMode.TriangleFan:
count = vertexCount - 2;
break;
case SharpGL.Enumerations.BeginMode.Quads:
count = vertexCount / 4;
break;
case SharpGL.Enumerations.BeginMode.QuadStrip:
count = vertexCount / 2 - 1;
break;
case SharpGL.Enumerations.BeginMode.Polygon:
count = 1;
break;
default:
throw new NotImplementedException();
}
result = true;
}
return(result);
}
/// <summary>
/// Get geometry's index(start from 0) according to <paramref name="lastVertexID"/> and <paramref name="mode"/>.
/// <para>Returns false if failed.</para>
/// </summary>
/// <param name="element"></param>
/// <param name="mode"></param>
/// <param name="lastVertexID">Refers to the last vertex that constructs the primitive.
/// <para>Ranges from 0 to (<paramref name="element"/>'s vertices' count - 1).</para></param>
/// <param name="index"></param>
/// <returns></returns>
public static bool GetGeometryIndex(this IColorCodedPicking element, SharpGL.Enumerations.BeginMode mode, uint lastVertexID, out uint index)
{
index = uint.MaxValue;
if (element == null)
{
return(false);
}
uint vertexCount = element.GetVertexCount();
if (lastVertexID < vertexCount)
{
switch (mode)
{
case SharpGL.Enumerations.BeginMode.Points:
// vertexID should range from 0 to vertexCount - 1.
index = lastVertexID;
break;
case SharpGL.Enumerations.BeginMode.Lines:
// vertexID should range from 0 to vertexCount - 1.
index = lastVertexID / 2;
break;
case SharpGL.Enumerations.BeginMode.LineLoop:
// vertexID should range from 0 to vertexCount.
if (lastVertexID == 0) // This is the last primitive.
{
index = vertexCount - 1;
}
else
{
index = lastVertexID - 1;
}
break;
case SharpGL.Enumerations.BeginMode.LineStrip:
index = lastVertexID - 1; // If lastVertexID is 0, this returns -1.
break;
case SharpGL.Enumerations.BeginMode.Triangles:
index = lastVertexID / 3;
break;
case SharpGL.Enumerations.BeginMode.TriangleString:
index = lastVertexID - 2; // if lastVertexID is 0 or 1, this returns -2 or -1.
break;
case SharpGL.Enumerations.BeginMode.TriangleFan:
index = lastVertexID - 2; // if lastVertexID is 0 or 1, this returns -2 or -1.
break;
case SharpGL.Enumerations.BeginMode.Quads:
index = lastVertexID / 4;
break;
case SharpGL.Enumerations.BeginMode.QuadStrip:
index = lastVertexID / 2 - 1; // If lastVertexID is 0 or 1, this returns -1.
break;
case SharpGL.Enumerations.BeginMode.Polygon:
index = 0;
break;
default:
throw new NotImplementedException();
}
}
return(true);
}
