DTK_CREATE_COMPLEX_SHAPE(3)					Draw Toolkit manual				       DTK_CREATE_COMPLEX_SHAPE(3)

NAME

       dtk_create_complex_shape - Creates or modify a shape to display custom and evolving content

SYNOPSIS

       #include <drawtk.h>

       dtk_hshape dtk_create_complex_shape(dtk_hshape shp,
			   unsigned int nvert, const float *vertpos,
			   const float *vertcolor, const float *texcoords,
			   unsigned int nind, const unsigned int *ind,
			   unsigned int type, dtk_htex tex);

DESCRIPTION

       dtk_create_complex_shape() creates a shape displaying a complex, custom and possibly evolving content described by vertex attribute buffers
       (vertpos, vertcolor and texcoords) and an array ind containing the indices of vertices whose order describes how to  connect  the  vertices
       altogether in order to form primitives (controlled by type). tex can be used to specify a texture to be mapped onto the shape.

       vertpos	should point to an array of nvert pairs of float values corresponding of the position (x,y) of each vertex. vertcolor should point
       to an array of nvert quatuples of float values corresponding of the color (R,G,B,A) of each vertex. texcoords can be  either  NULL  or  can
       point  to  an  array  of nvert pairs of float values corresponding to the texture coordinates (u,v) of the vertex. If texcoords is NULL, no
       texture will be used even if tex is not null.

       ind should point to an array of nind indices of the vertices in the vertex attribute buffers. This list of indices determines how the  ver-
       tices form the primitives and depends on type zhich can take one the following value (See OpenGL manual to have detail):

       DTK_TRIANGLE_STRIP
	      The  first three vertices defines the first triangle (and their order is significant). Each subsequent vertex defines a new triangle
	      using that point along with two vertices from the previous triangle.

       DTK_TRIANGLE_FAN
	      A triangle fan is the same as a triangle strip with one exception: the first vertex of the list is always the first vertex  of  each
	      triangle.

       DTK_TRIANGLES
	      Separate triangles are specified. Every 3 indices defines in the order a triangle. If nind is not a multiple of 3, the excedent 1 or
	      2 indices are ignored.

       DTK_LINE_STRIP
	      A series of one or more connected line segments is specified by enclosing a series of two or more endpoints. In this case,  the  ith
	      index specifies the end point of the i-1st segment and the start point of the ith segment.

       DTK_LINES
	      Individual line segments, each specified by a pair of vertices. If nind is odd, then the last index is ignored.

       shp  can be used to modify a previously created shape. If it is non-null, the handle will be used to modify the shape referenced by shp: no
       new shape is created and the returned value is ensured to be shp in case of success, NULL otherwise. If shp  is	NULL,  the  function  will
       attempt to create a new shape.

       The  arrays  vertpos, vertcolor, texcoords and ind are not copied into internal structures of the created shape. This allows one to dynami-
       cally change any aspect of the shape. However, in return it forces to keep the buffers allocated during the whole life time of the shape.

RETURN VALUE

       In case of success the function returns the handle to the newly created or modified shape. If the shp  argument	is  non-null,  the  handle
       returned is the same value. In case of error, NULL is returned.

THREAD SAFETY

       The data contained into the buffers are accessed only during the creation and the draw of the shape. So if the data is updated in a differ-
       ent thread than the one used for drawing, some locking is needed.

SEE ALSO

       dtk_create_shape(3)

EPFL
								       2010					       DTK_CREATE_COMPLEX_SHAPE(3)