GLAPI/glGetTexParameter

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glGetTexParameter
Core in version 4.6
Core since version 1.0

glGetTexParameter: return texture parameter values

Function Definition

 void glGetTexParameterfv(GLenum target, GLenum pname, GLfloat * params);
 void glGetTexParameteriv(GLenum target, GLenum pname, GLint * params);
 void glGetTexParameterIiv(GLenum target, GLenum pname, GLint * params);
 void glGetTexParameterIuiv(GLenum target, GLenum pname, GLuint * params);
target
Specifies the symbolic name of the target texture. GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_1D_ARRAY, GL_TEXTURE_2D_ARRAY, GL_TEXTURE_3D, GL_TEXTURE_RECTANGLE, GL_TEXTURE_CUBE_MAP, and GL_TEXTURE_CUBE_MAP_ARRAY are accepted.
pname
Specifies the symbolic name of a texture parameter. GL_TEXTURE_BASE_LEVEL, GL_TEXTURE_BORDER_COLOR, GL_TEXTURE_COMPARE_MODE, GL_TEXTURE_COMPARE_FUNC, GL_TEXTURE_IMMUTABLE_FORMAT, GL_TEXTURE_LOD_BIAS, GL_TEXTURE_MAG_FILTER, GL_TEXTURE_MAX_LEVEL, GL_TEXTURE_MAX_LOD, GL_TEXTURE_MIN_FILTER, GL_TEXTURE_MIN_LOD, GL_TEXTURE_SWIZZLE_R, GL_TEXTURE_SWIZZLE_G, GL_TEXTURE_SWIZZLE_B, GL_TEXTURE_SWIZZLE_A, GL_TEXTURE_SWIZZLE_RGBA, GL_TEXTURE_WRAP_S, GL_TEXTURE_WRAP_T, and GL_TEXTURE_WRAP_R are accepted.
params
Returns the texture parameters.

Description

glGetTexParameter returns in params the value or values of the texture parameter specified as pname. target defines the target texture. GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_3D, GL_TEXTURE_1D_ARRAY, GL_TEXTURE_2D_ARRAY, GL_TEXTURE_RECTANGLE, GL_TEXTURE_CUBE_MAP, GL_TEXTURE_CUBE_MAP_ARRAY specify one-, two-, or three-dimensional, one-dimensional array, two-dimensional array, rectangle, cube-mapped or cube-mapped array texturing, respectively. pname accepts the same symbols as glTexParameter, with the same interpretations:

GL_TEXTURE_MAG_FILTER
Returns the single-valued texture magnification filter, a symbolic constant. The initial value is GL_LINEAR.
GL_TEXTURE_MIN_FILTER
Returns the single-valued texture minification filter, a symbolic constant. The initial value is GL_NEAREST_MIPMAP_LINEAR.
GL_TEXTURE_MIN_LOD
Returns the single-valued texture minimum level-of-detail value. The initial value is -1000.
GL_TEXTURE_MAX_LOD
Returns the single-valued texture maximum level-of-detail value. The initial value is 1000.
GL_TEXTURE_BASE_LEVEL
Returns the single-valued base texture mipmap level. The initial value is 0.
GL_TEXTURE_MAX_LEVEL
Returns the single-valued maximum texture mipmap array level. The initial value is 1000.
GL_TEXTURE_SWIZZLE_R
Returns the red component swizzle. The initial value is GL_RED.
GL_TEXTURE_SWIZZLE_G
Returns the green component swizzle. The initial value is GL_GREEN.
GL_TEXTURE_SWIZZLE_B
Returns the blue component swizzle. The initial value is GL_BLUE.
GL_TEXTURE_SWIZZLE_A
Returns the alpha component swizzle. The initial value is GL_ALPHA.
GL_TEXTURE_SWIZZLE_RGBA
Returns the component swizzle for all channels in a single query.
GL_TEXTURE_WRAP_S
Returns the single-valued wrapping function for texture coordinate s, a symbolic constant. The initial value is GL_REPEAT.
GL_TEXTURE_WRAP_T
Returns the single-valued wrapping function for texture coordinate t, a symbolic constant. The initial value is GL_REPEAT.
GL_TEXTURE_WRAP_R
Returns the single-valued wrapping function for texture coordinate r, a symbolic constant. The initial value is GL_REPEAT.
GL_TEXTURE_BORDER_COLOR
Returns four integer or floating-point numbers that comprise the RGBA color of the texture border. Floating-point values are returned in the range [0, 1]. Integer values are returned as a linear mapping of the internal floating-point representation such that 1.0 maps to the most positive representable integer and -1.0 maps to the most negative representable integer. The initial value is (0, 0, 0, 0).
GL_TEXTURE_COMPARE_MODE
Returns a single-valued texture comparison mode, a symbolic constant. The initial value is GL_NONE. See glTexParameter.
GL_TEXTURE_COMPARE_FUNC
Returns a single-valued texture comparison function, a symbolic constant. The initial value is GL_LEQUAL. See glTexParameter.

In addition to the parameters that may be set with glTexParameter, glGetTexParameter accepts the following read-only parameters:

GL_TEXTURE_IMMUTABLE_FORMAT
Returns non-zero if the texture has an immutable format. Textures become immutable if their storage is specified with glTexStorage1D, glTexStorage2D or glTexStorage3D. The initial value is GL_FALSE.

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.

See Also

glTexParameter, glTexStorage1D, glTexStorage2D, glTexStorage3D

Copyright

Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2010-2011 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.