glGetTexLevelParameter

NAME

glGetTexLevelParameterfv, glGetTexLevelParameteriv -- return texture parameter values for a specific level of detail

C SPECIFICATION

void glGetTexLevelParameterfv(GLenum target,
                              GLint level,
                              GLenum pname,
                              GLfloat *params)
void glGetTexLevelParameteriv(GLenum target,
                              GLint level,
                              GLenum pname,
                              GLint *params)

PARAMETERS

target: Specifies the symbolic name of the target texture, either GL_TEXTURE_1D or GL_TEXTURE_2D.
level: Specifies the level-of-detail number of the desired image. Level 0 is the base image level. Level n is the nth mipmap reduction image.
pname: Specifies the symbolic name of a texture parameter. GL_TEXTURE_WIDTH, GL_TEXTURE_HEIGHT, GL_TEXTURE_COMPONENTS and GL_TEXTURE_BORDER are accepted.
params: Returns the requested data.

DESCRIPTION

glGetTexLevelParameter returns in params texture parameter values for a specific level-of-detail value, specified as level. target defines the target texture, either GL_TEXTURE_1D or GL_TEXTURE_2D, to specify one- or two-dimensional texturing. pname specifies the texture parameter whose value or values will be returned.

The accepted parameter names are as follows:

GL_TEXTURE_WIDTH: params returns a single value, the width of the texture image. This value includes the border of the texture image.
GL_TEXTURE_HEIGHT: params returns a single value, the height of the texture image. This value includes the border of the texture image.
GL_TEXTURE_COMPONENTS: params returns a single value, the number of components in the texture image.
GL_TEXTURE_BORDER: params returns a single value, the width in pixels of the border of the texture image.

NOTES

If an error is generated, no change is made to the contents of params.

ERRORS

GL_INVALID_ENUM is generated if target or pname is not an accepted value.

GL_INVALID_VALUE is generated if level is less than zero or greater than ld max, where max is the returned value of GL_MAX_TEXTURE_SIZE.

GL_INVALID_OPERATION is generated if glGetTexLevelParamter is called between a call to glBegin and the corresponding call to glEnd.