glGetHistogramParameter is used to query parameter values for the current histogram or for a proxy. The histogram state information may be queried by calling glGetHistogramParameter with a target of GL_HISTOGRAM (to obtain information for the current histogram table) or GL_PROXY_HISTOGRAM (to obtain information from the most recent proxy request) and one of the following values for the pname argument:center; lb lb l l. _ Parameter Description _ GL_HISTOGRAM_WIDTH Histogram table width GL_HISTOGRAM_FORMAT Internal GL_HISTOGRAM_RED_SIZE Red component counter size, in bits GL_HISTOGRAM_GREEN_SIZE Green component counter size, in bits center; lb lb l l. _ Parameter Description _ GL_HISTOGRAM_BLUE_SIZE Blue component counter size, in bits GL_HISTOGRAM_ALPHA_SIZE Alpha component counter size, in bits GL_HISTOGRAM_LUMINANCE_SIZE Luminance component counter size, in bits GL_HISTOGRAM_SINK Value of the sink parameter _