GLHISTOGRAM - Online Linux Manual PageSection : 3G
NAME"glHistogram − define histogram table
C SPECIFICATIONvoid glHistogram( GLenum target, GLsizei width,
GLenum internalformat,
GLboolean sink )
PARAMETERStarget The histogram whose parameters are to be set. Must be one of GL_HISTOGRAM or GL_PROXY_HISTOGRAM. width The number of entries in the histogram table. Must be a power of 2. internalformat The of entries in the histogram table. Must be one of GL_ALPHA, GL_ALPHA4, GL_ALPHA8, GL_ALPHA12, GL_ALPHA16, GL_LUMINANCE, GL_LUMINANCE4, GL_LUMINANCE8, GL_LUMINANCE12, GL_LUMINANCE16, GL_LUMINANCE_ALPHA, GL_LUMINANCE4_ALPHA4, GL_LUMINANCE6_ALPHA2, GL_LUMINANCE8_ALPHA8, GL_LUMINANCE12_ALPHA4, GL_LUMINANCE12_ALPHA12, GL_LUMINANCE16_ALPHA16, GL_R3_G3_B2, GL_RGB, GL_RGB4, GL_RGB5, GL_RGB8, GL_RGB10, GL_RGB12, GL_RGB16, GL_RGBA, GL_RGBA2, GL_RGBA4, GL_RGB5_A1, GL_RGBA8, GL_RGB10_A2, GL_RGBA12, or GL_RGBA16. sink If GL_TRUE, pixels will be consumed by the histogramming process and no drawing or texture loading will take place. If GL_FALSE, pixels will proceed to the minmax process after histogramming.
DESCRIPTIONWhen GL_HISTOGRAM is enabled, RGBA color components are converted to histogram table indices by clamping to the range [0,1], multiplying by the width of the histogram table, and rounding to the nearest integer. The table entries selected by the RGBA indices are then incremented. (If the internal of the histogram table includes luminance, then the index derived from the R color component determines the luminance table entry to be incremented.) If a histogram table entry is incremented beyond its maximum value, then its value becomes undefined. (This is not an error.) Histogramming is performed only for RGBA pixels (though these may be specified originally as color indices and converted to RGBA by index table lookup). Histogramming is enabled with glEnable and disabled with glDisable. When target is GL_HISTOGRAM, glHistogram redefines the current histogram table to have width entries of the specified by internalformat. The entries are indexed 0 through width~-~1, and all entries are initialized to zero. The values in the previous histogram table, if any, are lost. If sink is GL_TRUE, then pixels are discarded after histogramming; no further processing of the pixels takes place, and no drawing, texture loading, or pixel readback will result. When target is GL_PROXY_HISTOGRAM, glHistogram computes all state information as if the histogram table were to be redefined, but does not actually define the new table. If the requested histogram table is too large to be supported, then the state information will be set to zero. This provides a way to determine if a histogram table with the given parameters can be supported.
NOTESglHistogram is present only if GL_ARB_imaging is returned when glGetString is called with an argument of GL_EXTENSIONS.
ERRORSGL_INVALID_ENUM is generated if target is not one of the allowable values. GL_INVALID_VALUE is generated if width is less than zero or is not a power of 2. GL_INVALID_ENUM is generated if internalformat is not one of the allowable values. GL_TABLE_TOO_LARGE is generated if target is GL_HISTOGRAM and the histogram table specified is too large for the implementation. GL_INVALID_OPERATION is generated if glHistogram is executed between the execution of glBegin and the corresponding execution of glEnd.
ASSOCIATED GETSglGetHistogramParameter
SEE ALSOglGetHistogram(3G), glResetHistogram(3G) 0
Johanes Gumabo
Data Size : 14,734 byte
man-g___lHistogram.3GBuild : 2024-12-05, 20:55 :
Visitor Screen : x
Visitor Counter ( page / site ) : 2 / 167,816
Visitor ID : :
Visitor IP : 18.116.37.200 :
Visitor Provider : AMAZON-02 :
Provider Position ( lat x lon ) : 39.962500 x -83.006100 : x
Provider Accuracy Radius ( km ) : 1000 :
Provider City : Columbus :
Provider Province : Ohio , : ,
Provider Country : United States :
Provider Continent : North America :
Visitor Recorder : Version :
Visitor Recorder : Library :
Online Linux Manual Page : Version : Online Linux Manual Page - Fedora.40 - march=x86-64 - mtune=generic - 24.12.05
Online Linux Manual Page : Library : lib_c - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Online Linux Manual Page : Library : lib_m - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Data Base : Version : Online Linux Manual Page Database - 24.04.13 - march=x86-64 - mtune=generic - fedora-38
Data Base : Library : lib_c - 23.02.07 - march=x86-64 - mtune=generic - fedora.36
Very long time ago, I have the best tutor, Wenzel Svojanovsky . If someone knows the email address of Wenzel Svojanovsky , please send an email to johanes_gumabo@yahoo.co.id .
If error, please print screen and send to johanes_gumabo@yahoo.co.id
Under development. Support me via PayPal.