NAME
glGetHistogram
- get histogram table
C SPECIFICATION
void ggllGGeettHHiissttooggrraamm(
GLenum _t_a_r_g_e_t,
GLboolean _r_e_s_e_t,
GLenum _f_o_r_m_a_t,
GLenum _t_y_p_e,
GLvoid _*_v_a_l_u_e_s )
PARAMETERS
-
_t_a_r_g_e_t
-
Must be
GGLL__HHIISSTTOOGGRRAAMM.
-
_r_e_s_e_t
-
If GGLL__TTRRUUEE, each component counter that is actually returned
is reset to zero. (Other counters are unaffected.)
If GGLL__FFAALLSSEE, none of the counters in the histogram table is modified.
-
_f_o_r_m_a_t
-
The of values to be returned in _v_a_l_u_e_s.
Must be one of
GGLL__RREEDD,
GGLL__GGRREEEENN,
GGLL__BBLLUUEE,
GGLL__AALLPPHHAA,
GGLL__RRGGBB,
GGLL__BBGGRR,
GGLL__RRGGBBAA,
GGLL__BBGGRRAA,
GGLL__LLUUMMIINNAANNCCEE, or
GGLL__LLUUMMIINNAANNCCEE__AALLPPHHAA.
-
_t_y_p_e
-
The type of values to be returned in _v_a_l_u_e_s.
Symbolic constants
GGLL__UUNNSSIIGGNNEEDD__BBYYTTEE,
GGLL__BBYYTTEE,
GGLL__BBIITTMMAAPP,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT,
GGLL__SSHHOORRTT,
GGLL__UUNNSSIIGGNNEEDD__IINNTT,
GGLL__IINNTT,
GGLL__FFLLOOAATT,
GGLL__UUNNSSIIGGNNEEDD__BBYYTTEE__33__33__22,
GGLL__UUNNSSIIGGNNEEDD__BBYYTTEE__22__33__33__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__55__66__55,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__55__66__55__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__44__44__44__44,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__44__44__44__44__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__55__55__55__11,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__11__55__55__55__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__IINNTT__88__88__88__88,
GGLL__UUNNSSIIGGNNEEDD__IINNTT__88__88__88__88__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__IINNTT__1100__1100__1100__22, and
GGLL__UUNNSSIIGGNNEEDD__IINNTT__22__1100__1100__1100__RREEVV
are accepted.
-
_v_a_l_u_e_s
-
A pointer to storage for the returned histogram table.
DESCRIPTION
ggllGGeettHHiissttooggrraamm returns the current histogram table as a one-dimensional image
with the same width as the histogram.
No pixel transfer operations are performed on this image, but pixel storage
modes that are applicable to 1D images are honored.
Color components that are requested in the specified _f_o_r_m_a_t, but which
are not included in the internal of the histogram, are returned as
zero.
The assignments of internal color components to the components
requested by _f_o_r_m_a_t are:
center;
lb lb
l l.
_
Internal Component Resulting Component
_
Red Red
Green Green
Blue Blue
Alpha Alpha
Luminance Red
_
NOTES
ggllGGeettHHiissttooggrraamm is present only if GGLL__AARRBB__iimmaaggiinngg is returned when ggllGGeettSSttrriinngg
is called with an argument of GGLL__EEXXTTEENNSSIIOONNSS.
ERRORS
GGLL__IINNVVAALLIIDD__EENNUUMM is generated if _t_a_r_g_e_t is not GGLL__HHIISSTTOOGGRRAAMM.
GGLL__IINNVVAALLIIDD__EENNUUMM is generated if _f_o_r_m_a_t is not one of the allowable
values.
GGLL__IINNVVAALLIIDD__EENNUUMM is generated if _t_y_p_e is not one of the allowable
values.
GGLL__IINNVVAALLIIDD__OOPPEERRAATTIIOONN is generated if ggllGGeettHHiissttooggrraamm is executed
between the execution of ggllBBeeggiinn and the corresponding
execution of ggllEEnndd.
GGLL__IINNVVAALLIIDD__OOPPEERRAATTIIOONN is generated if _t_y_p_e is one of
GGLL__UUNNSSIIGGNNEEDD__BBYYTTEE__33__33__22,
GGLL__UUNNSSIIGGNNEEDD__BBYYTTEE__22__33__33__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__55__66__55, or
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__55__66__55__RREEVV
and _f_o_r_m_a_t is not GGLL__RRGGBB.
GGLL__IINNVVAALLIIDD__OOPPEERRAATTIIOONN is generated if _t_y_p_e is one of
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__44__44__44__44,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__44__44__44__44__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__55__55__55__11,
GGLL__UUNNSSIIGGNNEEDD__SSHHOORRTT__11__55__55__55__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__IINNTT__88__88__88__88,
GGLL__UUNNSSIIGGNNEEDD__IINNTT__88__88__88__88__RREEVV,
GGLL__UUNNSSIIGGNNEEDD__IINNTT__1100__1100__1100__22, or
GGLL__UUNNSSIIGGNNEEDD__IINNTT__22__1100__1100__1100__RREEVV
and _f_o_r_m_a_t is neither GGLL__RRGGBBAA nor GGLL__BBGGRRAA.
SEE ALSO
ggllHHiissttooggrraamm((33GG)),
ggllRReesseettHHiissttooggrraamm((33GG)),
ggllGGeettHHiissttooggrraammPPaarraammeetteerr((33GG))