---
name: "dtk_create_circle_str"
section: "3"
platform: "linux"
package: "libdrawtk-dev"
version: "2.0-2.1"
release: "Debian 8 (Jessie)"
platforms: ["linux"]
url: "https://new.carta.tech/dtk_create_circle_str"
---

# dtk\_create\_circle\_str(3)

Create and modify circular strip

## NAME

dtk\_create\_circle\_str - Create and modify circular strip

## SYNOPSIS

**#include \<drawtk.h\>**

**dtk\_hshape dtk\_create\_circle\_str(dtk\_hshape** *shp***,**\
                 **float** *cx***, float** *cy***, float** *r***, float** *thick***,**\
                 **const float \****color***, unsigned int** *numpoints***);**\

## DESCRIPTION

**dtk\_create\_circle\_str**() creates an approximation of a circular strip of radius *r* centered at (*cx*,*cy*) using *num\_points* vertices. The radius *r* is always referred to the outer circle.

*thick* represents the thickness of the strip. If *thick* is negative or greater than *r*, the call fails.

*shp* and *color* have the same usage and meaning as for other shape creation function:

- \*

  *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*.  If *shp* is *NULL*, the function will attempt to create a new shape.

- \*

  *color* should point to a 4 float array containing a normalized RGBA value (i.e. each component is between 0.0 and 1.0).

## RETURN VALUE

In case of success these functions return 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. If *thick* is negative or greater than *r*, *NULL* is returned.

## SEE ALSO

[**dtk\_create\_circle**(3)](/dtk_create_circle/3.md),[**dtk\_destroy\_shape**(3)](/dtk_destroy_shape/3.md)