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GL_EXT_histogram
EXT_histogram
Name Strings
GL_EXT_histogram
Version
$Date: 1996/04/05 19:17:02 $ $Revision: 1.24 $
Number
11
Dependencies
EXT_abgr affects the definition of this extension
EXT_texture is required
Overview
This extension defines pixel operations that count occurences of
specific color component values (histogram) and that track the minimum
and maximum color component values (minmax). An optional mode allows
pixel data to be discarded after the histogram and/or minmax operations
are completed. Otherwise the pixel data continue on to the next
operation unaffected.
void HistogramEXT(enum target,
sizei width,
enum internalformat,
boolean sink);
void ResetHistogramEXT(enum target);
void GetHistogramEXT(enum target,
boolean reset,
enum format,
enum type,
void* values);
void GetHistogramParameterivEXT(enum target,
enum pname,
int* params);
void GetHistogramParameterfvEXT(enum target,
enum pname,
float* params);
void MinmaxEXT(enum target,
enum internalformat,
boolean sink);
void ResetMinmaxEXT(enum target);
void GetMinmaxEXT(enum target,
boolean reset,
enum format,
enum type,
void* values);
void GetMinmaxParameterivEXT(enum target,
enum pname,
int* params);
void GetMinmaxParameterfvEXT(enum target,
enum pname,
float* params);
Accepted by the <cap> parameter of Enable, Disable, and IsEnabled, by
the <pname> parameter of GetBooleanv, GetIntegerv, GetFloatv, and
GetDoublev, and by the <target> parameter of HistogramEXT,
ResetHistogramEXT, GetHistogramEXT, GetHistogramParameterivEXT, and
GetHistogramParameterfvEXT:
HISTOGRAM_EXT 0x8024
Accepted by the <target> parameter of HistogramEXT,
GetHistogramParameterivEXT, and GetHistogramParameterfvEXT:
PROXY_HISTOGRAM_EXT 0x8025
Accepted by the <pname> parameter of GetHistogramParameterivEXT and
GetHistogramParameterfvEXT:
HISTOGRAM_WIDTH_EXT 0x8026
HISTOGRAM_FORMAT_EXT 0x8027
HISTOGRAM_RED_SIZE_EXT 0x8028
HISTOGRAM_GREEN_SIZE_EXT 0x8029
HISTOGRAM_BLUE_SIZE_EXT 0x802A
HISTOGRAM_ALPHA_SIZE_EXT 0x802B
HISTOGRAM_LUMINANCE_SIZE_EXT 0x802C
HISTOGRAM_SINK_EXT 0x802D
Accepted by the <cap> parameter of Enable, Disable, and IsEnabled, by
the <pname> parameter of GetBooleanv, GetIntegerv, GetFloatv, and
GetDoublev, and by the <target> parameter of MinmaxEXT, ResetMinmaxEXT,
GetMinmaxEXT, GetMinmaxParameterivEXT, and GetMinmaxParameterfvEXT:
MINMAX_EXT 0x802E
Accepted by the <pname> parameter of GetMinmaxParameterivEXT and
GetMinmaxParameterfvEXT:
MINMAX_FORMAT_EXT 0x802F
MINMAX_SINK_EXT 0x8030
Additions to Chapter 2 of the 1.0 Specification (OpenGL Operation)
A new error token value, TABLE_TOO_LARGE_EXT, is defined and added to
table 2.3:
Offending
command
Error Description ignored?
----- ----------- ---------
INVALID_ENUM enum argument out of range Yes
INVALID_VALUE Numeric argument out of range Yes
INVALID_OPERATION Operation illegal in current state Yes
STACK_OVERFLOW Command would cause a stack overflow Yes
STACK_UNDERFLOW Command would cause a stack underflow Yes
OUT_OF_MEMORY Not enough memory left to execute command Unknown
TEXTURE_TOO_LARGE_EXT The specified texture is too large Yes
TABLE_TOO_LARGE_EXT The specified table is too large Yes
Table 2.3: Summary of GL errors
and defined as follows:
GL_TABLE_TOO_LARGE_EXT 0x8031
Additions to Chapter 3 of the 1.0 specification (Rasterization)
The specification of histogram and minmax operators is added to
the GL Specification in section 3.6.2, "Pixel Transfer Modes." A
histogram table is specified using the HistogramEXT command. Its
<target> parameter must be HISTOGRAM_EXT if a histogram table is
to be specified. (Optional target value PROXY_HISTOGRAM_EXT is
described below.) Its <width> parameter, which must be a power of
2, specifies the number of entries in the histogram table, and its
<internalformat> parameter specifies the format of each table
entry. <sink> specifies whether pixel groups will be consumed by
the histogram operation (TRUE) or passed on to the minmax
operation (FALSE). The error INVALID_VALUE results if <width> is
specified less than zero or is not a power of 2. The error
TABLE_TOO_LARGE_EXT results if the specified histogram table is
too large for the implementation. (See the PROXY discussion
below.) The error INVALID_ENUM results if <internalformat> is not
one of the values accepted by the <components> parameter of
TexImage2D (as defined by EXT_texture), except that values 1, 2,
3, 4, INTENSITY_EXT, INTENSITY4_EXT, INTENSITY8_EXT,
INTENSITY12_EXT, and INTENSITY16_EXT are not accepted.
If no error results from the execution of HistogramEXT, the specified
histogram table is redefined to have <width> entries, each with the
specified internal format. The entries are indexed zero through N-1,
where N is the <width> of the table. Each value in each entry is set
to zero. The values in the previous histogram table, if any, are lost.
It is acceptable for an implementation to vary its allocation of
internal component resolution based any HistogramEXT parameter, but the
allocation must not be a function of any other factor, and cannot be
changed once it is established. In particular, allocations must be
invariant -- the same allocation must be made each time a histogram is
specified with the same parameter values. Provision is made for an
application to determine what component resolutions are available
without having to fully specify the histogram (see below).
A minmax table is specified using the MinmaxEXT command. Its <target>
parameter must be MINMAX_EXT. <internalformat> may be any of the token
values accepted by the <components> parameter of TexImage2D, except that
1, 2, 3, 4, INTENSITY_EXT, INTENSITY4_EXT, INTENSITY8_EXT,
INTENSITY12_EXT, and INTENSITY16_EXT are not accepted. <sink> is set
to TRUE or FALSE. The resulting minmax table always has 2 entries,
each with values corresponding only to the components of the internal
format.
The operations of the histogram and minmax are added to the GL
Specification in section 3.6.3, "Rasterization of Pixel
Rectangles, immediately following the subsection "Index Lookup",
and immediately prior to the subsection "Final Conversion".
Histogram and minmax operations are performed only for RGBA pixel
groups, though these groups may have been specified as color
indices and converted to RGBA by index table lookup. Histogram
and minmax are enabled and disabled by calling Enable or Disable
with HISTOGRAM_EXT or MINMAX_EXT passed as the <cap> parameter.
If HISTOGRAM_EXT is enabled and the width of the table is
non-zero, and the pixel groups contain RGBA values, then indices
Ri, Gi, Bi, and Ai are derived from the red, green, blue, and
alpha components of each pixel group (without modifying these
components) by clamping the components to [0,1], multiplying each
by one less than the width of the histogram table, and rounding
each to the nearest integer. If the format of the HISTOGRAM_EXT
table includes red or luminance, the red or luminance component of
histogram entry Ri is incremented by one. If the format of the
HISTOGRAM_EXT table includes green, the green component of
histogram entry Gi is incremented by one. The blue and alpha
components of histogram entries Bi and Ai are incremented in the
same way. If a histogram entry component is incremented beyond
its maximum value, its value becomes undefined. (This is not an
error.)
If MINMAX_EXT is enabled, and the pixel groups contain RGBA values, then
the red, green, blue, and alpha components of each group are compared
to the minimum and maximum values for each, which are stored in the
2-element minmax table. (The first element stores the minimum values,
the second stores the maximum values.) If the format of this table
includes red or luminance, the red component value replaces the red or
luminance value in the minimum table element if and only if it is less
than that component. Likewise, if the format includes red or luminance
and the red component of the group is greater than the red or luminance
value in the maximum element, the red group component replaces the red
or luminance maximum component. If the format of the table includes
green, the green group component conditionally replaces the green
minimum and/or maximum if it is smaller or larger, respectively. The
blue and alpha group components are similarly tested and replaced, if
the table format includes blue and/or alpha. The internal type of the
minimum and maximum component values is floating point -- there are no
semantics defined for the treatment of group component values that are
outside the representable range of the minimum and maximum values.
By default histogram and minmax operations have no effect on the stream
of pixel groups being processed. If HISTOGRAM_EXT is enabled and the
histogram <sink> parameter was specified as TRUE, however, all RGBA
pixel groups are discarded immediately after the histogram operation
is completed. Because histogram precedes minmax, no minmax operation
is performed. No pixel fragments are generated, no change is made to
texture memory contents, and no pixel values are returned. If
MINMAX_EXT is enabled and the minmax <sink> parameter was specified
as TRUE, all RGBA pixel groups are discarded immediately after the
minmax operation is completed. Because minmax follows histogram, a
histogram operation with <sink> set to FALSE may precede such a minmax
operation. Again no pixel fragments are generated, no change is made
to texture memory contents, and no pixel values are returned.
The current contents of the histogram tables are queried using
GetHistogramEXT. <target> must be HISTOGRAM_EXT. <format> must be one
of RED, GREEN, BLUE, ALPHA, RGB, RGBA, ABGR_EXT, LUMINANCE, or
LUMINANCE_ALPHA. <type> must be UNSIGNED_BYTE, BYTE, UNSIGNED_SHORT,
SHORT, UNSIGNED_INT, INT, or FLOAT. A 1-dimensional image with the
same width as the histogram is returned to <values>. No pixel
transfer operations are performed on this image, but pixel storage
modes that are applicable to ReadPixels are performed. Color
components that are requested in the specified <format>, but which are
not included in the internal format of the histogram, are returned as
zero. The assignments of internal color components to the components
requested by <format> are
internal component resulting component
------------------ -------------------
red red
green green
blue blue
alpha alpha
luminance red
<reset> is either TRUE or FALSE. If TRUE, each component counter that
is actually returned is reset to zero. Counters that are not returned
are not modified. All counters of all elements of histogram <target>
are reset to zero when ResetHistogramEXT is called. <target> must be
either HISTOGRAM_EXT. It is not an error to reset or query the contents
of a histogram table with zero entries.
The current contents of the minmax tables are queried using
GetMinmaxEXT. <target> must be MINMAX_EXT. <format> must be one
of RED, GREEN, BLUE, ALPHA, RGB, RGBA, ABGR_EXT, LUMINANCE, or
LUMINANCE_ALPHA. <type> must be UNSIGNED_BYTE, BYTE,
UNSIGNED_SHORT, SHORT, UNSIGNED_INT, INT, or FLOAT. A
1-dimensional image with width of 2 is returned to values. No
pixel transfer operations are performed on this image, but pixel
storage modes that are applicable to ReadPixels are
performed. Color components that are requested in the specified
<format>, but which are not included in the internal format of the
minmax table, are returned as zero. The assignment of internal
color components to the components requested by <format> are the
same as for histogram return.
<reset> is either TRUE or FALSE. If TRUE, each minimum value that is
actually returned is reset to the maximum representable value, and each
maximum value that is returned is reset to the minimum representable
value. Minimum and maximum values that are not returned are not
modified. All minimum and maximum values of minmax table <target> are
reset to their maximum and minimum representable values, respectively,
when ResetMinmaxEXT is called. <target> must be MINMAX_EXT.
Query support
-------------
Alternate sets of partial histogram state are defined for the
proxy histogram PROXY_HISTOGRAM_EXT. Specifically,
HISTOGRAM_WIDTH_EXT, HISTOGRAM_FORMAT, HISTOGRAM_RED_SIZE_EXT,
HISTOGRAM_GREEN_SIZE_EXT, HISTOGRAM_BLUE_SIZE_EXT,
HISTOGRAM_ALPHA_SIZE_EXT, and HISTOGRAM_LUMINANCE_SIZE_EXT are
maintained for the proxy histogram. When HistogramEXT is called
with <target> set to PROXY_HISTOGRAM_EXT, these proxy state values
are always recomputed and updated, even if the histogram is too
large to actually be used. If the histogram is too large, all of
these state variables are set to zero. If the histogram could be
accommodated by Histogram called with <target> HISTOGRAM_EXT,
these values are set as though HISTOGRAM_EXT were being defined.
All of these state values can be queried with
GetHistogramParameterivEXT or GetHistogramParameterfvEXT with
<target> set to PROXY_HISTOGRAM_EXT. Calling HistogramEXT with
<target> PROXY_HISTOGRAM_EXT has no effect on the actual
histogram.
There is no image associated with PROXY_HISTOGRAM_EXT. Therefore
PROXY_HISTOGRAM_EXT cannot be used as a histogram, and its image must
never be queried using GetHistogramEXT. (The error INVALID_ENUM
results if this is attempted.)
Additions to Chapter 4 of the 1.0 Specification (Per-Fragment Operations
and the Framebuffer)
The operation of histogram and minmax during pixel copy and query
operations is identical to the operation during pixel drawing and
texture image definition.
Additions to Chapter 5 of the 1.0 Specification (Special Functions)
HistogramEXT with a proxy target, GetHistogramEXT,
GetHistogramParameterivEXT, GetHistogramParameterfvEXT, GetMinmaxEXT,
GetMinmaxParameterivEXT, and GetMinmaxParameterfvEXT are not included in
display lists -- they are executed immediately when called.
Additions to Chapter 6 of the 1.0 Specification (State and State Requests)
Integer and floating point query functions GetHistogramParameterivEXT
and GetHistogramParameterfvEXT are provided. <target> must be
HISTOGRAM_EXT or PROXY_HISTOGRAM_EXT. <pname> is one of
HISTOGRAM_FORMAT_EXT, HISTOGRAM_WIDTH_EXT, HISTOGRAM_RED_SIZE_EXT,
HISTOGRAM_GREEN_SIZE_EXT, HISTOGRAM_BLUE_SIZE_EXT,
HISTOGRAM_ALPHA_SIZE_EXT, HISTOGRAM_LUMINANCE_SIZE_EXT,
or HISTOGRAM_SINK_EXT. The value of the specified parameter is
returned in <params>.
Integer and floating point query functions GetMinmaxParameterivEXT and
GetMinmaxParameterfvEXT are provided. <target> must be MINMAX_EXT.
<pname> is MINMAX_FORMAT_EXT or MINMAX_SINK_EXT. The value of the
specified parameter is returned in <params>.
Additions to the GLX Specification
None
GLX Protocol
Ten new GL commands are added.
The following four rendering commands are sent to the server as
part of a glXRender request:
HistogramEXT
2 20 rendering command length
2 4110 rendering command opcode
4 ENUM target
4 INT32 width
4 ENUM internalformat
1 BOOL sink
3 unused
ResetHistogramEXT
2 8 rendering command length
2 4112 rendering command opcode
4 ENUM target
MinmaxEXT
2 16 rendering command length
2 4111 rendering command opcode
4 ENUM target
4 ENUM internalformat
1 BOOL sink
3 unused
ResetMinmaxEXT
2 8 rendering command length
2 4113 rendering command opcode
4 ENUM target
The remaining commands are non-rendering commands. These commands
are sent separately (i.e., not as part of a glXRender or
glXRenderLarge request), using the glXVendorPrivateWithReply
request:
GetHistogramEXT
1 CARD8 opcode (X assigned)
1 17 GLX opcode (glXVendorPrivateWithReply)
2 7 request length
4 5 vendor specific opcode
4 GLX_CONTEXT_TAG context tag
4 ENUM target
4 ENUM format
4 ENUM type
1 BOOL swap_bytes
1 BOOL reset
2 unused
=>
1 1 reply
1 unused
2 CARD16 sequence number
4 n reply length
24 unused
4*n LISTofBYTE pixels
If <format> or <type> is not valid then the command is
erroneous and n=0. The structure of <pixels> is described in
Appendix A of the GLX Protocol Specification, "Pixel Data",
using the parameters <swap_bytes>, <format>, and <type>. No
extra padding is needed after <pixels> because the image
format already pads to 32 bits.
GetHistogramParameterfvEXT
1 CARD8 opcode (X assigned)
1 17 GLX opcode (glXVendorPrivateWithReply)
2 5 request length
4 6 vendor specific opcode
4 GLX_CONTEXT_TAG context tag
4 ENUM target
4 ENUM pname
=>
1 1 reply
1 unused
2 CARD16 sequence number
4 m reply length, m = (n==1 ? 0 : n)
4 unused
4 CARD32 n
if (n=1) this follows:
4 INT32 params
12 unused
otherwise this follows:
16 unused
n*4 LISTofINT32 params
Note that n may be zero, indicating that a GL error
occurred. Also, n>1, is for future extensibility.
GetHistogramParameterivEXT
1 CARD8 opcode (X assigned)
1 17 GLX opcode (glXVendorPrivateWithReply)
2 5 request length
4 7 vendor specific opcode
4 GLX_CONTEXT_TAG context tag
4 ENUM target
4 ENUM pname
=>
1 1 reply
1 unused
2 CARD16 sequence number
4 m reply length, m = (n==1 ? 0 : n)
4 unused
4 CARD32 n
if (n=1) this follows:
4 INT32 params
12 unused
otherwise this follows:
16 unused
n*4 LISTofINT32 params
Note that n may be zero, indicating that a GL error
occurred. Also, n>1, is for future extensibility.
GetMinmaxEXT
1 CARD8 opcode (X assigned)
1 17 GLX opcode (glXVendorPrivateWithReply)
2 7 request length
4 8 vendor specific opcode
4 GLX_CONTEXT_TAG context tag
4 ENUM target
4 ENUM format
4 ENUM type
1 BOOL swap_bytes
1 BOOL reset
2 unused
=>
1 1 reply
1 unused
2 CARD16 sequence number
4 n reply length
24 unused
4*n LISTofBYTE pixels
If <format> or <type> is not valid then the command is
erroneous and n=0. The structure of <pixels> is described in
Appendix A of the GLX Protocol Specification, "Pixel Data",
using the parameters <swap_bytes>, <format>, and <type>. No
extra padding is needed after <pixels> because the image
format already pads to 32 bits.
GetMinmaxParameterfvEXT
1 CARD8 opcode (X assigned)
1 17 GLX opcode (glXVendorPrivateWithReply)
2 5 request length
4 9 vendor specific opcode
4 GLX_CONTEXT_TAG context tag
4 ENUM target
4 ENUM pname
=>
1 1 reply
1 unused
2 CARD16 sequence number
4 m reply length, m = (n==1 ? 0 : n)
4 unused
4 CARD32 n
if (n=1) this follows:
4 INT32 params
12 unused
otherwise this follows:
16 unused
n*4 LISTofINT32 params
Note that n may be zero, indicating that a GL error
occurred. Also, n>1, is for future extensibility.
GetMinmaxParameterivEXT
1 CARD8 opcode (X assigned)
1 17 GLX opcode (glXVendorPrivateWithReply)
2 5 request length
4 10 vendor specific opcode
4 GLX_CONTEXT_TAG context tag
4 ENUM target
4 ENUM pname
=>
1 1 reply
1 unused
2 CARD16 sequence number
4 m reply length, m = (n==1 ? 0 : n)
4 unused
4 CARD32 n
if (n=1) this follows:
4 INT32 params
12 unused
otherwise this follows:
16 unused
n*4 LISTofINT32 params
Note that n may be zero, indicating that a GL error
occurred. Also, n>1, is for future extensibility.
Dependencies on EXT_abgr
If EXT_abgr is supported, the <format> parameters of GetHistogramEXT
and GetMinmaxEXT accept ABGR_EXT. Otherwise they do not.
Dependencies on EXT_texture
EXT_texture is required. This extension builds on the notion of
internal image format, which is defined by EXT_texture.
Errors
INVALID_ENUM is generated if HistogramEXT parameter <target> is not
HISTOGRAM_EXT or PROXY_HISTOGRAM_EXT.
INVALID_VALUE is generated if HistogramEXT parameter <width> is less
than zero or is not a power of 2.
INVALID_ENUM is generated if HistogramEXT parameter <internalformat> is
not ALPHA, RGB, RGBA, LUMINANCE, LUMINANCE_ALPHA, or one of the tokens
defined by the EXT_texture extension. (Values 1, 2, 3, and 4 are not
accepted as internal formats by HistogramEXT).
TABLE_TOO_LARGE_EXT is generated if HistogramEXT is called with
parameter <target> of HISTOGRAM_EXT and the histogram as specified is
too large for the implementation.
INVALID_ENUM is generated if ResetHistogramEXT parameter <target> is
not HISTOGRAM_EXT.
INVALID_ENUM is generated if GetHistogramEXT parameter <target> is not
HISTOGRAM_EXT.
INVALID_ENUM is generated if GetHistogramEXT parameter <format> is not
RED, GREEN, BLUE, ALPHA, RGB, RGBA, ABGR_EXT, LUMINANCE, or
LUMINANCE_ALPHA.
INVALID_ENUM is generated if GetHistogramEXT parameter <type> is not
UNSIGNED_BYTE, BYTE, UNSIGNED_SHORT, SHORT, UNSIGNED_INT, INT, or FLOAT.
INVALID_ENUM is generated if GetHistogramParameterivEXT or
GetHistogramParameterfvEXT parameter <target> is not HISTOGRAM_EXT or
PROXY_HISTOGRAM_EXT.
INVALID_ENUM is generated if GetHistogramParameterivEXT or
GetHistogramParameterfvEXT parameter <pname> is not
HISTOGRAM_FORMAT_EXT, HISTOGRAM_WIDTH_EXT, HISTOGRAM_RED_SIZE_EXT,
HISTOGRAM_GREEN_SIZE_EXT, HISTOGRAM_BLUE_SIZE_EXT,
HISTOGRAM_ALPHA_SIZE_EXT, HISTOGRAM_LUMINANCE_SIZE_EXT, or
HISTOGRAM_SINK_EXT. INVALID_ENUM is also generated if
GetHistogramParameterivEXT or GetHistogramParameterfvEXT parameter
<target> specifies the proxy histogram and <pname> specifies a
piece of state which is not maintained for the proxy histogram.
INVALID_OPERATION is generated if HistogramEXT, ResetHistogramEXT,
GetHistogramEXT, GetHistogramParameterivEXT, or
GetHistogramParameterfvEXT is called between execution of Begin and the
corresponding execution of End.
INVALID_ENUM is generated if MinmaxEXT parameter <target> is not
MINMAX_EXT.
INVALID_ENUM is generated if MinmaxEXT parameter <internalformat> is
not ALPHA, RGB, RGBA, LUMINANCE, LUMINANCE_ALPHA, or one of the tokens
defined by the EXT_texture extension. (Values 1, 2, 3, and 4 are not
accepted as internal formats by MinmaxEXT).
INVALID_ENUM is generated if ResetMinmaxEXT parameter <target> is not
MINMAX_EXT.
INVALID_ENUM is generated if GetMinmaxEXT parameter <target> is not
MINMAX_EXT.
INVALID_ENUM is generated if GetMinmaxEXT parameter <format> is not
RED, GREEN, BLUE, ALPHA, RGB, RGBA, ABGR_EXT, LUMINANCE, or
LUMINANCE_ALPHA.
INVALID_ENUM is generated if GetMinmaxEXT parameter <type> is not
UNSIGNED_BYTE, BYTE, UNSIGNED_SHORT, SHORT, UNSIGNED_INT, INT, or FLOAT.
INVALID_ENUM is generated if GetMinmaxParameterivEXT or
GetMinmaxParameterfvEXT parameter <target> is not MINMAX_EXT.
INVALID_ENUM is generated if GetMinmaxParameterivEXT or
GetMinmaxParameterfvEXT parameter <pname> is not MINMAX_FORMAT_EXT or
MINMAX_SINK_EXT.
INVALID_OPERATION is generated if MinmaxEXT, ResetMinmaxEXT,
GetMinmaxEXT, GetMinmaxParameterivEXT, or GetMinmaxParameterfvEXT is
called between execution of Begin and the corresponding execution of End.
New State
Get Value Get Command Type Initial Value Attribute
--------- ----------- ---- ------------- ---------
HISTOGRAM_EXT IsEnabled B False pixel/enable
HISTOGRAM GetHistogramEXT I empty -
HISTOGRAM_WIDTH_EXT GetHistogramParameterivEXT Z+ 0 -
HISTOGRAM_FORMAT_EXT GetHistogramParameterivEXT Z33 RGBA -
HISTOGRAM_RED_SIZE_EXT GetHistogramParameterivEXT Z+ 0 -
HISTOGRAM_GREEN_SIZE_EXT GetHistogramParameterivEXT Z+ 0 -
HISTOGRAM_BLUE_SIZE_EXT GetHistogramParameterivEXT Z+ 0 -
HISTOGRAM_ALPHA_SIZE_EXT GetHistogramParameterivEXT Z+ 0 -
HISTOGRAM_LUMINANCE_SIZE_EXT GetHistogramParameterivEXT Z+ 0 -
HISTOGRAM_SINK_EXT GetHistogramParameterivEXT B False -
MINMAX_EXT IsEnabled B False pixel/enable
MINMAX GetMinmaxEXT Rn (M,M,M,M),(m,m,m,m) -
MINMAX_FORMAT_EXT GetMinmaxParameterivEXT Z33 RGBA -
MINMAX_SINK_EXT GetMinmaxParameterivEXT B False -
Note, M and m are the maximum and minimum representable values of the
minmax components.
New Implementation Dependent State
None
Implementation Support
List of OpenGL implementations supporting the GL_EXT_histogram extension
Original File
Original text file for the GL_EXT_histogram extension
Page generated on Sun Nov 20 18:37:25 2005