gletwistextrusion(3gle) [debian man page]

gleTwistExtrusion(3GLE) 						GLE						   gleTwistExtrusion(3GLE)

NAME

       gleTwistExtrusion - Extrude arbitrary 2D contour along arbitrary 3D path, specifying local rotations (twists).

SYNTAX

       void gleTwistExtrusion (int ncp,
		       gleDouble contour[][2],
		       gleDouble cont_normal[][2],
		       gleDouble up[3],
		       int npoints,
		       gleDouble point_array[][3],
		       float color_array[][3],
		       gleDouble twist_array[]);

ARGUMENTS

       ncp	 number of contour points

       contour	 2D contour

       cont_normal
		 2D contour normals

       up	 up vector for contour

       npoints	 numpoints in poly-line

       point_array
		 polyline vertices

       color_array
		 colors at polyline verts

       twist_array
		 contour twists (in degrees)

DESCRIPTION

       Extrude	arbitrary  2D contour along arbitrary 3D path, specifying local rotations (twists). As the contour is extruded, it will be twisted
       by the amount specified in the array "twist_array". The angles are measured in degrees, and the rotation is about the origin of the contour
       coordinate system.

       The argument "contour" specifies the 2D contour to be extruded, while the argument "point_array" specifies the path along which to extrude.
       The vector "up" defines the orientation of the contour y-axis in real 3D space.

       Note that neither the very first segment, nor the very last segment are drawn. The first and last segments serve only to define	the  angle
       of the join at the very ends of the polyline. Thus, to draw one segment, three must be specified. To draw two segments, four must be speci-
       fied, etc.

       The normal array may be NULL. If it is, normal vectors will NOT be automatically generated, and the object will look terrible when lit.

       The color array may be NULL. If NULL, the current color is used. If not NULL, the glColor3f() routine is used to set the color;	therefore,
       specifying the glColorMaterial() subroutine before this primitive can be used to set diffuse, specular, ambient, etc. colors.

SEE ALSO

       gleExtrusion, gleSuperExtrusion

AUTHOR

       Linas Vepstas (linas@linas.org)

GLE
									3.0						   gleTwistExtrusion(3GLE)

GLUNEXTCONTOUR(3G)														GLUNEXTCONTOUR(3G)

NAME

       gluNextContour - mark the beginning of another contour

C SPECIFICATION

       void gluNextContour( GLUtesselator* tess,
			    GLenum type )

PARAMETERS

       tess  Specifies the tessellation object (created with gluNewTess).

       type  Specifies the type of the contour being defined. Valid values are GLU_EXTERIOR, GLU_INTERIOR, GLU_UNKNOWN, GLU_CCW, and GLU_CW.

DESCRIPTION

       gluNextContour  is  used  in  describing  polygons  with  multiple contours. After the first contour has been described through a series of
       gluTessVertex calls, a gluNextContour call indicates that the previous contour is complete and that the next contour  is  about	to  begin.
       Another	series	of gluTessVertex calls is then used to describe the new contour. This process can be repeated until all contours have been
       described.

       type defines what type of contour follows.  The legal contour types are as follows:

       GLU_EXTERIOR	 An exterior contour defines an exterior boundary of the polygon.

       GLU_INTERIOR	 An interior contour defines an interior boundary of the polygon (such as a hole).

       GLU_UNKNOWN	 An unknown contour is analyzed by the library to determine if it is interior or exterior.

       GLU_CCW,

       GLU_CW		 The first GLU_CCW or GLU_CW contour defined is considered to be exterior. All other contours are considered to  be  exte-
			 rior  if  they  are  oriented in the same direction (clockwise or counterclockwise) as the first contour, and interior if
			 they are not.

       If one contour is of type GLU_CCW or GLU_CW, then all contours must be of the same type (if they are not, then all GLU_CCW and GLU_CW  con-
       tours will be changed to GLU_UNKNOWN).

       Note that there is no real difference between the GLU_CCW and GLU_CW contour types.

       Before  the  first  contour  is	described, gluNextContour can be called to define the type of the first contour.  If gluNextContour is not
       called before the first contour, then the first contour is marked GLU_EXTERIOR.

       This command is obsolete and is provided for backward compatibility only. Calls to gluNextContour are mapped to gluTessEndContour  followed
       by gluTessBeginContour.

EXAMPLE

       A quadrilateral with a triangular hole in it can be described as follows:

       gluBeginPolygon(tobj);
	  gluTessVertex(tobj, v1, v1);
	  gluTessVertex(tobj, v2, v2);
	  gluTessVertex(tobj, v3, v3);
	  gluTessVertex(tobj, v4, v4); gluNextContour(tobj, GLU_INTERIOR);
	  gluTessVertex(tobj, v5, v5);
	  gluTessVertex(tobj, v6, v6);
	  gluTessVertex(tobj, v7, v7); gluEndPolygon(tobj);

SEE ALSO

       gluBeginPolygon, gluNewTess, gluTessCallback, gluTessVertex, gluTessBeginContour

																GLUNEXTCONTOUR(3G)