GLTEXIMAGE3D(3G) GLTEXIMAGE3D(3G)
NAME
glTexImage3D - specify a three-dimensional texture image
C SPECIFICATION
void glTexImage3D( GLenum target,
GLint level,
GLenum internalformat,
GLsizei width,
GLsizei height,
GLsizei depth,
GLint border,
GLenum format,
GLenum type,
const GLvoid *pixels )
PARAMETERS
target Specifies the target texture. Must be GLTEXTURE3D or
GLPROXYTEXTURE3D.
level Specifies the level-of-detail number. Level 0 is the
base image level. Level n is the nth mipmap reduction
image.
internalformat Specifies the number of color components in the tex-
ture. Must be 1, 2, 3, or 4, or one of the following
symbolic constants: GLALPHA, GLALPHA4, GLALPHA8,
GLALPHA12, GLALPHA16, GLUMINANCE, GLUMINANCE4,
GLUMINANCE8, GLUMINANCE12, GLUMINANCE16,
GLUMINANCEALPHA, GLUMINANCE4ALPHA4,
GLUMINANCE6ALPHA2, GLUMINANCE8ALPHA8,
GLUMINANCE12ALPHA4, GLUMINANCE12ALPHA12,
GLUMINANCE16ALPHA16, GLINTENSITY, GLINTENSITY4,
GLINTENSITY8, GLINTENSITY12, GLINTENSITY16,
GLR3G3B2, GLRGB, GLRGB4, GLRGB5, GLRGB8,
GLRGB100, GLRGB12, GLRGB16, GLRGBA, GLRGBA2,
GLRGBA4, GLRGB5A1, GLRGBA8, GLRGB100A2, GLRGBA12,
or GLRGBA16.
width Specifies the width of the texture image. Must be 2^n
]2 (border) for some integer n. All implementations
support texture images that are at least 64 texels
wide.
height Specifies the height of the texture image. Must be 2^m
]2 (border) for some integer m. All implementations
support texture images that are at least 64 texels
high.
depth Specifies the depth of the texture image. Must be 2^k
]2 (border) for some integer k. All implementations
support texture images that are at least 64 texels
deep.
border Specifies the width of the border. Must be either 0 or
1.
format Specifies the of the pixel data. The following sym-
bolic values are accepted: GLCOLORINDEX, GLRED,
GLGREN, GLBLUE, GLALPHA, GLRGB, GLBGR, GLRGBA,
GLBGRA, GLUMINANCE, and GLUMINANCEALPHA.
type Specifies the data type of the pixel data. The follow-
ing symbolic values are accepted: GLUNSIGNEDBYTE,
GLBYTE, GLBITMAP, GLUNSIGNEDSHORT, GLSHORT,
GLUNSIGNEDINT, GLINT, GLFLOAT
GLUNSIGNEDBYTE332, GLUNSIGNEDBYTE233REV,
GLUNSIGNEDSHORT565, GLUNSIGNEDSHORT565REV,
GLUNSIGNEDSHORT4444,
GLUNSIGNEDSHORT4444REV,
GLUNSIGNEDSHORT5551,
GLUNSIGNEDSHORT1555REV, GLUNSIGNEDINT8888,
GLUNSIGNEDINT8888REV,
GLUNSIGNEDINT1001001002, and
GLUNSIGNEDINT2100100100REV.
pixels Specifies a pointer to the image data in memory.
DESCRIPTION
Texturing maps a portion of a specified texture image onto each graphi-
cal primitive for which texturing is enabled. To enable and disable
three-dimensional texturing, call glEnable and glDisable with argument
GLTEXTURE3D.
To define texture images, call glTexImage3D. The arguments describe
the parameters of the texture image, such as height, width, depth,
width of the border, level-of-detail number (see glTexParameter), and
number of color components provided. The last three arguments describe
how the image is represented in memory; they are identical to the pixel
formats used for glDrawPixels.
If target is GLPROXYTEXTURE3D, no data is read from pixels, but all
of the texture image state is recalculated, checked for consistency,
and checked against the implementation's capabilities. If the implemen-
tation cannot handle a texture of the requested texture size, it sets
all of the image state to 0, but does not generate an error (see
glGetError). To query for an entire mipmap array, use an image array
level greater than or equal to 1.
If target is GLTEXTURE3D, data is read from pixels as a sequence of
signed or unsigned bytes, shorts, or longs, or single-precision float-
ing-point values, depending on type. These values are grouped into
sets of one, two, three, or four values, depending on format, to form
elements. If type is GLBITMAP, the data is considered as a string of
unsigned bytes (and format must be GLCOLORINDEX). Each data byte is
treated as eight 1-bit elements, with bit ordering determined by
GLUNPACKLSBFIRST (see glPixelStore).
The first element corresponds to the lower left corner of the texture
image. Subsequent elements progress left-to-right through the remain-
ing texels in the lowest row of the texture image, and then in succes-
sively higher rows of the texture image. The final element corresponds
to the upper right corner of the texture image.
format determines the composition of each element in pixels. It can
assume one of eleven symbolic values:
GLCOLORINDEX
Each element is a single value, a color index. The GL con-
verts it to fixed point (with an unspecified number of zero
bits to the right of the binary point), shifted left or right
depending on the value and sign of GLINDEXSHIFT, and added
to GLINDEXOFSET (see
glPixelTransfer). The resulting index is converted to a set
of color components using the GLPIXELMAPITOR,
GLPIXELMAPITOG, GLPIXELMAPITOB, and
GLPIXELMAPITOA tables, and clamped to the range [0,1].
GLRED Each element is a single red component. The GL converts it
to floating point and assembles it into an RGBA element by
attaching 0 for green and blue, and 1 for alpha. Each compo-
nent is then multiplied by the signed scale factor
GLcSCALE, added to the signed bias GLcBIAS, and clamped
to the range [0,1] (see glPixelTransfer).
GLGREN Each element is a single green component. The GL converts it
to floating point and assembles it into an RGBA element by
attaching 0 for red and blue, and 1 for alpha. Each compo-
nent is then multiplied by the signed scale factor
GLcSCALE, added to the signed bias GLcBIAS, and clamped
to the range [0,1] (see glPixelTransfer).
GLBLUE Each element is a single blue component. The GL converts it
to floating point and assembles it into an RGBA element by
attaching 0 for red and green, and 1 for alpha. Each compo-
nent is then multiplied by the signed scale factor
GLcSCALE, added to the signed bias GLcBIAS, and clamped
to the range [0,1] (see glPixelTransfer).
GLALPHA Each element is a single alpha component. The GL converts it
to floating point and assembles it into an RGBA element by
attaching 0 for red, green, and blue. Each component is then
multiplied by the signed scale factor GLcSCALE, added to
the signed bias GLcBIAS, and clamped to the range [0,1]
(see glPixelTransfer).
GLRGB
GLBGR Each element is an RGB triple. The GL converts it to float-
ing point and assembles it into an RGBA element by attaching
1 for alpha. Each component is then multiplied by the signed
scale factor GLcSCALE, added to the signed bias GLcBIAS,
and clamped to the range [0,1] (see
glPixelTransfer).
GLRGBA
GLBGRA Each element contains all four components. Each component is
multiplied by the signed scale factor GLcSCALE, added to
the signed bias GLcBIAS, and clamped to the range [0,1]
(see glPixelTransfer).
GLUMINANCE
Each element is a single luminance value. The GL converts it
to floating point, then assembles it into an RGBA element by
replicating the luminance value three times for red, green,
and blue and attaching 1 for alpha. Each component is then
multiplied by the signed scale factor GLcSCALE, added to
the signed bias GLcBIAS, and clamped to the range [0,1]
(see glPixelTransfer).
GLUMINANCEALPHA
Each element is a luminance/alpha pair. The GL converts it
to floating point, then assembles it into an RGBA element by
replicating the luminance value three times for red, green,
and blue. Each component is then multiplied by the signed
scale factor GLcSCALE, added to the signed bias GLcBIAS,
and clamped to the range [0,1] (see
glPixelTransfer).
Refer to the glDrawPixels reference page for a description of the
acceptable values for the type parameter.
If an application wants to store the texture at a certain resolution or
in a certain , it can request the resolution and with internalformat.
The GL will choose an internal representation that closely approximates
that requested by internalformat, but it may not match exactly. (The
representations specified by GLUMINANCE, GLUMINANCEALPHA, GLRGB,
and GLRGBA must match exactly. The numeric values 1, 2, 3, and 4 may
also be used to specify the above representations.)
Use the GLPROXYTEXTURE3D target to try out a resolution and update
and recompute its best match for the requested storage resolution and .
To then query this state, call glGetTexLevelParameter. If the texture
cannot be accommodated, texture state is set to 0.
A one-component texture image uses only the red component of the RGBA
color extracted from pixels. A two-component image uses the R and A
values. A three-component image uses the R, G, and B values. A four-
component image uses all of the RGBA components.
NOTES
Texturing has no effect in color index mode.
The texture image can be represented by the same data formats as the
pixels in a glDrawPixels command, except that GLSTENCILINDEX and
GLDEPTHCOMPONENT cannot be used. glPixelStore and glPixelTransfer
modes affect texture images in exactly the way they affect
glDrawPixels.
glTexImage3D is available only if the GL version is 1.2 or greater.
Internal formats other than 1, 2, 3, or 4 may be used only if the GL
version is 1.1 or greater.
pixels may be a null pointer. In this case texture memory is allocated
to accommodate a texture of width width, height height, and depth
depth. You can then download subtextures to initialize this texture
memory. The image is undefined if the user tries to apply an unini-
tialized portion of the texture image to a primitive.
Formats GLBGR, and GLBGRA and types GLUNSIGNEDBYTE332,
GLUNSIGNEDBYTE233REV, GLUNSIGNEDSHORT565,
GLUNSIGNEDSHORT565REV, GLUNSIGNEDSHORT4444,
GLUNSIGNEDSHORT4444REV, GLUNSIGNEDSHORT5551,
GLUNSIGNEDSHORT1555REV, GLUNSIGNEDINT8888,
GLUNSIGNEDINT8888REV, GLUNSIGNEDINT1001001002, and
GLUNSIGNEDINT2100100100REV are available only if the GL version is
1.2 or greater.
When the GLARBmultitexture extension is supported, glTexImage3D spec-
ifies the three-dimensional texture for the current texture unit, spec-
ified with glActiveTextureARB.
If the GLARBimaging extension is supported, RGBA elements may also be
processed by the imaging pipeline. The following stages may be applied
to an RGBA color before color component clamping to the range [0, 1]:
1. Color component replacement by the color table specified for
GLCOLORTABLE, if enabled. See glColorTable.
2. Color component replacement by the color table specified for
GLPOSTCONVOLUTIONCOLORTABLE, if enabled. See glColorTable.
3. Transformation by the color matrix. See glatrixode.
4. RGBA components may be multiplied by GLPOSTCOLORMATRIXcSCALE,
and added to GLPOSTCOLORMATRIXcBIAS, if enabled. See
glPixelTransfer.
5. Color component replacement by the color table specified for
GLPOSTCOLORMATRIXCOLORTABLE, if enabled. See glColorTable.
ERORS
GLINVALIDENUM is generated if target is not GLTEXTURE3D or
GLPROXYTEXTURE3D.
GLINVALIDENUM is generated if format is not an accepted
constant. Format constants other than GLSTENCILINDEX and
GLDEPTHCOMPONENT are accepted.
GLINVALIDENUM is generated if type is not a type constant.
GLINVALIDENUM is generated if type is GLBITMAP and format is not
GLCOLORINDEX.
GLINVALIDVALUE is generated if level is less than 0.
GLINVALIDVALUE may be generated if level is greater than log2(max),
where max is the returned value of GLMAXTEXTURESIZE.
GLINVALIDVALUE is generated if internalformat is not 1, 2, 3, 4, or
one of the accepted resolution and symbolic constants.
GLINVALIDVALUE is generated if width, height, or depth is less than 0
or greater than 2 ] GLMAXTEXTURESIZE, or if either cannot be repre-
sented as 2^k ]2 (border) for some integer value of k.
GLINVALIDVALUE is generated if border is not 0 or 1.
GLINVALIDOPERATION is generated if glTexImage3D is executed between
the execution of glBegin and the corresponding execution of glEnd.
GLINVALIDOPERATION is generated if type is one of
GLUNSIGNEDBYTE332, GLUNSIGNEDBYTE233REV,
GLUNSIGNEDSHORT565, or GLUNSIGNEDSHORT565REV and format is
not GLRGB.
GLINVALIDOPERATION is generated if type is one of
GLUNSIGNEDSHORT4444, GLUNSIGNEDSHORT4444REV,
GLUNSIGNEDSHORT5551, GLUNSIGNEDSHORT1555REV,
GLUNSIGNEDINT8888, GLUNSIGNEDINT8888REV,
GLUNSIGNEDINT1001001002, or GLUNSIGNEDINT2100100100REV and for-
mat is neither GLRGBA nor GLBGRA.
ASOCIATED GETS
glGetTexImage
glIsEnabled with argument GLTEXTURE3D
SEE ALSO
glActiveTextureARB, glCopyPixels, glCopyTexImage1D, glCopyTexImage2D,
glCopyTexSubImage1D, glCopyTexSubImage2D, glCopyTexSubImage3D,
glDrawPixels, glPixelStore, glPixelTransfer, glTexEnv, glTexGen,
glTexImage1D, glTexImage2D, glTexSubImage1D, glTexSubImage2D,
glTexSubImage3D, glTexParameter
GLTEXIMAGE3D(3G)
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