Commit fd75029f authored by Yong Bakos's avatar Yong Bakos Committed by Daniel Stone

util: Document wl_fixed_t

Add doxygen comments for wl_fixed_t and its methods.

Although wl_fixed_t can be thought of as an opaque struct, it is a typedef. As
such, doxygen does not provide an elegant means of documenting it as both a
'class' with members and as a typedef. In other words, documenting it as a class
gives us a nice doxygen page for wl_fixed_t and its related methods, but this
leaves the typedef documentation blank in the documentation for wayland-util,
and does not provide a link to the documentation for wl_fixed_t. Hence, this
patch does not treat wl_fixed_t as a class/struct, resulting in the typedef
being documented and keeping the functions listed in wayland-util, rather than a
separate unlinked page devoted to just wl_fixed_t.
Signed-off-by: 's avatarYong Bakos <ybakos@humanoriented.com>
Reviewed-by: Peter Hutterer's avatarPeter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Daniel Stone's avatarDaniel Stone <daniels@collabora.com>
parent 2281bc08
......@@ -511,8 +511,23 @@ wl_array_copy(struct wl_array *array, struct wl_array *source);
(const char *) pos < ((const char *) (array)->data + (array)->size); \
(pos)++)
/**
* Fixed-point number
*
* A `wl_fixed_t` is a 24.8 signed fixed-point number with a sign bit, 23 bits
* of integer precision and 8 bits of decimal precision. Consider `wl_fixed_t`
* as an opaque struct with methods that facilitate conversion to and from
* `double` and `int` types.
*/
typedef int32_t wl_fixed_t;
/**
* Converts a fixed-point number to a floating-point number.
*
* \param f Fixed-point number to convert
*
* \return Floating-point representation of the fixed-point argument
*/
static inline double
wl_fixed_to_double(wl_fixed_t f)
{
......@@ -526,6 +541,13 @@ wl_fixed_to_double(wl_fixed_t f)
return u.d - (3LL << 43);
}
/**
* Converts a floating-point number to a fixed-point number.
*
* \param d Floating-point number to convert
*
* \return Fixed-point representation of the floating-point argument
*/
static inline wl_fixed_t
wl_fixed_from_double(double d)
{
......@@ -539,12 +561,26 @@ wl_fixed_from_double(double d)
return u.i;
}
/**
* Converts a fixed-point number to an integer.
*
* \param f Fixed-point number to convert
*
* \return Integer component of the fixed-point argument
*/
static inline int
wl_fixed_to_int(wl_fixed_t f)
{
return f / 256;
}
/**
* Converts an integer to a fixed-point number.
*
* \param i Integer to convert
*
* \return Fixed-point representation of the integer argument
*/
static inline wl_fixed_t
wl_fixed_from_int(int i)
{
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment