Name
gl.GetTexLevelParameter -- return texture parameter values for a specific level of detail
Synopsis
param = gl.GetTexLevelParameter(target, level, pname)
Function
gl.GetTexLevelParameter() returns texture parameter values for a specific level-of-detail value, specified as level. target defines the target texture, either #GL_TEXTURE_1D, #GL_TEXTURE_2D, #GL_PROXY_TEXTURE_1D, or #GL_PROXY_TEXTURE_2D.

#GL_MAX_TEXTURE_SIZE is not really descriptive enough. It has to report the largest square texture image that can be accommodated with mipmaps and borders, but a long skinny texture, or a texture without mipmaps and borders, may easily fit in texture memory. The proxy targets allow the user to more accurately query whether the GL can accommodate a texture of a given configuration. If the texture cannot be accommodated, the texture state variables, which may be queried with gl.GetTexLevelParameter(), are set to 0. If the texture can be accommodated, the texture state values will be set as they would be set for a non-proxy target.

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. The initial value is 0.

#GL_TEXTURE_HEIGHT
params returns a single value, the height of the texture image. This value includes the border of the texture image. The initial value is 0.

#GL_TEXTURE_DEPTH
params returns a single value, the depth of the texture image. This value includes the border of the texture image. The initial value is 0.

#GL_TEXTURE_INTERNAL_FORMAT
params returns a single value, the internal format of the texture image.

#GL_TEXTURE_BORDER
params returns a single value, the width in pixels of the border of the texture image. The initial value is 0.

#GL_TEXTURE_XXX_SIZE
The internal storage resolution of an individual component (XXX can be RED, GREEN, BLUE, ALPHA, LUMINANCE, INTENSITY, DEPTH). The resolution chosen by the GL will be a close match for the resolution requested by the user with the component argument of gl.TexImage1D(), gl.TexImage2D(), and gl.CopyTexImage(). The initial value is 0.

Please consult an OpenGL reference manual for more information.

Inputs
target
specifies the symbolic name of the target texture, either #GL_TEXTURE_1D, #GL_TEXTURE_2D, #GL_PROXY_TEXTURE_1D, or #GL_PROXY_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 (see above for possible values)
Results
param
requested data
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 0.

#GL_INVALID_VALUE may be generated if level is greater than ld(max), where max is the returned value of #GL_MAX_TEXTURE_SIZE.

#GL_INVALID_OPERATION is generated if gl.GetTexLevelParameter() is executed between the execution of gl.Begin() and the corresponding execution of gl.End() .


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