Line Strips
Line Strips are entities (objects) which
represent a number of continuous sequences of straight segments joined together. As
entities Line Strips have local frame and can be joined to a parent or have
children.
Programmatically Line Strips can be created with a call to
Create method of
Object Generator with eType parameter
set to eObjTypeLineStrip or by importing a VRML file containing "IndexedLineSet" node.
Yet another method is to call
IStdShape.Line(pt0, pt1) This will create a simple straight line. Internal
points which can lie on a curved shape can be added as described below.
Line Strips can also be created interactively:
1. With the help of the New Object
editor of 3D Debugger:
Go to Model > New Object menu option. Select Curve \ Strip node. Press
Modify button. In the "Object Type" make sure that the "Generic Strip" radio
button is on (default). Use Segment group to enter coordinates of
consecutive points in the strip
2. Using Line
Direct User Access command.
3. By importing a VRML file with "IndexedLineSet" node in Modeling
Studio or Data Flow sample.
Runtime access to Line Strips is available via
ISectionLineStrip
interface.
Line Strips are derived from Point Sets to use all its properties. This
means that to modify geometry and other base properties of a line strip one
needs to query ISectionPointSet
from ISectionLineStrip or
related IEntity_DG. When
Color Per Vertex is true color of lines
is interpolated between the ends of segments. Increasing
Point Size will show points at
joints.
Use IArray2 as described in the
Point Sets topic to add or remove sampling point.
Line Strips implement ICurve interface,
which allows calculation of intermediate points and length
Properties:
Line Width - Width in pixels
Index - Array of integers, which refer to
points in the base Points Array.
Linked components of the strip are separated by index -1. If the strip
consists of a single component it does not have to have -1 separators.
Stipple - (Boolean) If true the line is rendered stippled
StippleStyle - (unsigned short) Specifies style of the line: Common styles:
0x00FF Dashed; 0x0101 Dotted; 0x1c47 Dash - Dot style. See online documentation
(MSDN site:
http://msdn.microsoft.com/en-us/library/ ) for glLineStipple OpenGL
function for other styles. This property has no effect if the Stipple property
is false
StippleFactor - (interger) Specifies how the stipple pattern is stretched.
See online documentation (MSDN site:
http://msdn.microsoft.com/en-us/library/ ) for glLineStipple OpenGL
function for details. This property has no effect if the Stipple property is
false
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