Glgetteximage - HP b2600 Reference Manual

glGetTexImage

glGetTexImage: return a texture image.
C Specification
void glGetTexImage(
Parameters
target
level
format
type
pixels
Description
glGetTexImage returns a texture image into pixels. target specifies whether the desired
texture image is one specified by glTexImage1D (GL_TEXTURE_1D) or by
glTexImage2D (GL_TEXTURE_2D). level specifies the level-of-detail number of the
desired image. format and type specify the format and type of the desired image array.
See the reference pages glTexImage1D and glDrawPixels for a description of the
acceptable values for the format and type parameters, respectively.
To understand the operation of glGetTexImage, consider the selected internal
four-component texture image to be an RGBA color buffer the size of the image. The
semantics of glGetTexImage are then identical to those of glReadPixels called with the
same format and type, with x and y set to 0, width set to the width of the texture image
(including border if one was specified), and height set to 1 for 1D images, or to the height
of the texture image (including border if one was specified) for 2D images.
Because the internal texture image is an RGBA image, pixel formats
GL_COLOR_INDEX, GL_STENCIL_INDEX, and GL_DEPTH_COMPONENT are not
accepted, and pixel type GL_BITMAP is not accepted.
Chapter 7
GLenum target,
GLint level,
GLenum format,
GLenum type,
GLvoid *pixels)
Specifies which texture is to be obtained. GL_TEXTURE_1D and
GL_TEXTURE_2D are accepted.
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.
Specifies a pixel format for the returned data.
The supported formats are GL_RED, GL_GREEN, GL_BLUE,
GL_ALPHA, GL_RGB, GL_RGBA, GL_LUMINANCE, and
GL_LUMINANCE_ALPHA.
Specifies a pixel type for the returned data. The supported types are
GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT,
GL_SHORT, GL_UNSIGNED_INT, GL_INT, and GL_FLOAT.
Returns the texture image. Should be a pointer to an array of the type
specified by type.
G
glGetTexImage
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