gluTessProperty man page on DigitalUNIX

Man page or keyword search:  
man Server   12896 pages
apropos Keyword Search (all sections)
Output format
DigitalUNIX logo
[printable version]

gluTessProperty()					     gluTessProperty()

NAME
       gluTessProperty - set a tessellation object property

SYNOPSIS
       void gluTessProperty(
	       GLUtesselator* tess,
	       GLenum which,
	       GLdouble data );

PARAMETERS
       Specifies  the tessellation object (created with gluNewTess()).	Speci‐
       fies the property to be set. Valid  values  are	GLU_TESS_WINDING_RULE,
       GLU_TESS_BOUNDARY_ONLY, GLU_TESS_TOLERANCE.  Specifies the value of the
       indicated property.

DESCRIPTION
       gluTessProperty() is used to control properties stored in  a  tessella‐
       tion  object.  These  properties	 affect	 the way that the polygons are
       interpreted and rendered. The legal values for which  are  as  follows:
       Determines  which parts of the polygon are on the "interior".  data may
       be  set	to  one	 of  GLU_TESS_WINDING_ODD,   GLU_TESS_WINDING_NONZERO,
       GLU_TESS_WINDING_POSITIVE,     or     GLU_TESS_WINDING_NEGATIVE,	    or
       GLU_TESS_WINDING_ABS_GEQ_TWO.

	      To understand how the winding  rule  works,  consider  that  the
	      input  contours  partition  the  plane into regions. The winding
	      rule determines which of these regions are inside the polygon.

	      For a single contour C, the winding number of a point x is  sim‐
	      ply  the	signed	number	of  revolutions we make around x as we
	      travel once around C (where CCW is  positive).  When  there  are
	      several  contours,  the  individual  winding numbers are summed.
	      This procedure associates a signed integer value with each point
	      x in the plane. Note that the winding number is the same for all
	      points in a single region.

	      The winding rule classifies a region as "inside" if its  winding
	      number  belongs  to the chosen category (odd, nonzero, positive,
	      negative, or absolute value of at least two). The	 previous  GLU
	      tessellator  (prior  to  GLU  1.2)  used	the  "odd"  rule.  The
	      "nonzero" rule is another common way  to	define	the  interior.
	      The other three rules are useful for polygon CSG operations.  Is
	      a boolean value ("value" should be set to GL_TRUE or  GL_FALSE).
	      When  set	 to  GL_TRUE,  a set of closed contours separating the
	      polygon interior and exterior are returned instead of a  tessel‐
	      lation.  Exterior	 contours are oriented CCW with respect to the
	      normal; interior contours are oriented  CW.  The	GLU_TESS_BEGIN
	      and  GLU_TESS_BEGIN_DATA callbacks use the type GL_LINE_LOOP for
	      each contour.  Specifies a tolerance  for	 merging  features  to
	      reduce  the  size	 of the output. For example, two vertices that
	      are very close to each other might be replaced by a single  ver‐
	      tex.  The tolerance is multiplied by the largest coordinate mag‐
	      nitude of any input vertex; this specifies the maximum  distance
	      that any feature can move as the result of a single merge opera‐
	      tion. If a single feature takes part  in	several	 merge	opera‐
	      tions, the total distance moved could be larger.

	      Feature  merging is completely optional; the tolerance is only a
	      hint.  The implementation is free to merge in some cases and not
	      in others, or to never merge features at all. The initial toler‐
	      ance is 0.

	      The current implementation merges	 vertices  only	 if  they  are
	      exactly  coincident, regardless of the current tolerance. A ver‐
	      tex is spliced into an edge only if the implementation is unable
	      to  distinguish  which  side of the edge the vertex lies on. Two
	      edges are merged only when both endpoints are identical.

SEE ALSO
       gluGetTessProperty(3)

							     gluTessProperty()
[top]

List of man pages available for DigitalUNIX

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net