229 lines
7.6 KiB
Plaintext
229 lines
7.6 KiB
Plaintext
|
'\" e
|
||
|
|
'\"! eqn | mmdoc
|
||
|
|
'\"macro stdmacro
|
||
|
|
.ds Vn Version 1.2
|
||
|
|
.ds Dt 6 March 1997
|
||
|
|
.ds Re Release 1.2.0
|
||
|
|
.ds Dp May 02 11:53
|
||
|
|
.ds Dm 37 build1dmi
|
||
|
|
.ds Xs 40806 9 build1dmipmaps.gl
|
||
|
|
.TH GLUBUILD1DMIPMAPS 3G
|
||
|
|
.SH NAME
|
||
|
|
.B "gluBuild1DMipmaps
|
||
|
|
\- builds a one-dimensional mipmap
|
||
|
|
|
||
|
|
.SH C SPECIFICATION
|
||
|
|
GLint \f3gluBuild1DMipmaps\fP(
|
||
|
|
GLenum \fItarget\fP,
|
||
|
|
.nf
|
||
|
|
.ta \w'\f3GLint \fPgluBuild1DMipmaps( 'u
|
||
|
|
GLint \fIinternalFormat\fP,
|
||
|
|
GLsizei \fIwidth\fP,
|
||
|
|
GLenum \fIformat\fP,
|
||
|
|
GLenum \fItype\fP,
|
||
|
|
const void \fI*data\fP )
|
||
|
|
.fi
|
||
|
|
|
||
|
|
.EQ
|
||
|
|
delim $$
|
||
|
|
.EN
|
||
|
|
.SH PARAMETERS
|
||
|
|
.TP \w'\fIinternalFormat\fP\ \ 'u
|
||
|
|
\f2target\fP
|
||
|
|
Specifies the target texture. Must be \%\f3GL_TEXTURE_1D\fP.
|
||
|
|
.TP
|
||
|
|
\f2internalFormat\fP
|
||
|
|
Requests the internal storage of the texture image. The most
|
||
|
|
current version of the SGI implementation of GLU does not check this
|
||
|
|
value for validity before passing it on to the underlying OpenGL
|
||
|
|
implementation. A value that is not accepted by the OpenGL
|
||
|
|
implementation will lead to an OpenGL error. The benefit of not
|
||
|
|
checking this value at the GLU level is that OpenGL extensions can add
|
||
|
|
new internal texture formats without requiring a revision of the GLU
|
||
|
|
implementation. Older implementations of GLU check this value and
|
||
|
|
raise a GLU error if it is not 1, 2, 3, or 4 or one of the following
|
||
|
|
symbolic constants:
|
||
|
|
\%\f3GL_ALPHA\fP,
|
||
|
|
\%\f3GL_ALPHA4\fP,
|
||
|
|
\%\f3GL_ALPHA8\fP,
|
||
|
|
\%\f3GL_ALPHA12\fP,
|
||
|
|
\%\f3GL_ALPHA16\fP,
|
||
|
|
\%\f3GL_LUMINANCE\fP,
|
||
|
|
\%\f3GL_LUMINANCE4\fP,
|
||
|
|
\%\f3GL_LUMINANCE8\fP,
|
||
|
|
\%\f3GL_LUMINANCE12\fP,
|
||
|
|
\%\f3GL_LUMINANCE16\fP,
|
||
|
|
\%\f3GL_LUMINANCE_ALPHA\fP,
|
||
|
|
\%\f3GL_LUMINANCE4_ALPHA4\fP,
|
||
|
|
\%\f3GL_LUMINANCE6_ALPHA2\fP,
|
||
|
|
\%\f3GL_LUMINANCE8_ALPHA8\fP,
|
||
|
|
\%\f3GL_LUMINANCE12_ALPHA4\fP,
|
||
|
|
\%\f3GL_LUMINANCE12_ALPHA12\fP,
|
||
|
|
\%\f3GL_LUMINANCE16_ALPHA16\fP,
|
||
|
|
\%\f3GL_INTENSITY\fP,
|
||
|
|
\%\f3GL_INTENSITY4\fP,
|
||
|
|
\%\f3GL_INTENSITY8\fP,
|
||
|
|
\%\f3GL_INTENSITY12\fP,
|
||
|
|
\%\f3GL_INTENSITY16\fP,
|
||
|
|
\%\f3GL_RGB\fP,
|
||
|
|
\%\f3GL_R3_G3_B2\fP,
|
||
|
|
\%\f3GL_RGB4\fP,
|
||
|
|
\%\f3GL_RGB5\fP,
|
||
|
|
\%\f3GL_RGB8\fP,
|
||
|
|
\%\f3GL_RGB10\fP,
|
||
|
|
\%\f3GL_RGB12\fP,
|
||
|
|
\%\f3GL_RGB16\fP,
|
||
|
|
\%\f3GL_RGBA\fP,
|
||
|
|
\%\f3GL_RGBA2\fP,
|
||
|
|
\%\f3GL_RGBA4\fP,
|
||
|
|
\%\f3GL_RGB5_A1\fP,
|
||
|
|
\%\f3GL_RGBA8\fP,
|
||
|
|
\%\f3GL_RGB10_A2\fP,
|
||
|
|
\%\f3GL_RGBA12\fP, or
|
||
|
|
\%\f3GL_RGBA16\fP.
|
||
|
|
.TP
|
||
|
|
\f2width\fP
|
||
|
|
Specifies the width, in pixels, of the texture image.
|
||
|
|
.TP
|
||
|
|
\f2format\fP
|
||
|
|
Specifies the of the pixel data.
|
||
|
|
Must be one of
|
||
|
|
\%\f3GL_COLOR_INDEX\fP,
|
||
|
|
\%\f3GL_DEPTH_COMPONENT\fP,
|
||
|
|
\%\f3GL_RED\fP,
|
||
|
|
\%\f3GL_GREEN\fP,
|
||
|
|
\%\f3GL_BLUE\fP,
|
||
|
|
\%\f3GL_ALPHA\fP,
|
||
|
|
\%\f3GL_RGB\fP,
|
||
|
|
\%\f3GL_RGBA\fP,
|
||
|
|
\%\f3GL_BGR\fP,
|
||
|
|
\%\f3GL_BGRA\fP,
|
||
|
|
\%\f3GL_LUMINANCE\fP,
|
||
|
|
\%\f3GL_LUMINANCE_ALPHA\fP.
|
||
|
|
.TP
|
||
|
|
\f2type\fP
|
||
|
|
Specifies the data type for \f2data\fP.
|
||
|
|
Must be one of
|
||
|
|
\%\f3GL_UNSIGNED_BYTE\fP,
|
||
|
|
\%\f3GL_BYTE\fP,
|
||
|
|
\%\f3GL_BITMAP\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT\fP,
|
||
|
|
\%\f3GL_SHORT\fP,
|
||
|
|
\%\f3GL_UNSIGNED_INT\fP,
|
||
|
|
\%\f3GL_INT\fP,
|
||
|
|
\%\f3GL_FLOAT\fP,
|
||
|
|
\%\f3GL_UNSIGNED_BYTE_3_3_2\fP,
|
||
|
|
\%\f3GL_UNSIGNED_BYTE_2_3_3_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_5_6_5\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_5_6_5_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_4_4_4_4\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_4_4_4_4_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_5_5_5_1\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_1_5_5_5_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_INT_8_8_8_8\fP,
|
||
|
|
\%\f3GL_UNSIGNED_INT_8_8_8_8_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_INT_10_10_10_2\fP, or
|
||
|
|
\%\f3GL_UNSIGNED_INT_2_10_10_10_REV\fP.
|
||
|
|
.TP
|
||
|
|
\f2data\fP
|
||
|
|
Specifies a pointer to the image data in memory.
|
||
|
|
.SH DESCRIPTION
|
||
|
|
\%\f3gluBuild1DMipmaps\fP builds a series of prefiltered one-dimensional texture maps of decreasing
|
||
|
|
resolutions called a mipmap. This is used for the antialiasing of
|
||
|
|
texture mapped primitives.
|
||
|
|
.P
|
||
|
|
A return value of zero indicates success, otherwise a GLU error code is
|
||
|
|
returned (see \%\f3gluErrorString\fP).
|
||
|
|
.P
|
||
|
|
Initially, the \f2width\fP of \f2data\fP is checked to see if it is
|
||
|
|
a power of 2. If not, a copy of \f2data\fP is scaled up or down to the
|
||
|
|
nearest power of 2. (If \f2width\fP is exactly between powers of 2, then
|
||
|
|
the copy of \f2data\fP will scale upwards.) This copy will be used for
|
||
|
|
subsequent mipmapping operations described below.
|
||
|
|
For example, if \f2width\fP is 57 then a copy of \f2data\fP
|
||
|
|
will scale up to 64 before mipmapping
|
||
|
|
takes place.
|
||
|
|
.P
|
||
|
|
Then, proxy textures (see \f3glTexImage1D\fP) are used to determine if
|
||
|
|
the implementation can fit the requested texture. If not, \f2width\fP is
|
||
|
|
continually halved until it fits.
|
||
|
|
.P
|
||
|
|
Next, a series of mipmap levels is built by decimating a copy of
|
||
|
|
\f2data\fP in half
|
||
|
|
until size $1 ~times~ 1$ is reached. At each level, each texel in the
|
||
|
|
halved mipmap level is an average of the corresponding two texels in the larger
|
||
|
|
mipmap level.
|
||
|
|
.P
|
||
|
|
\f3glTexImage1D\fP is called to load each of these mipmap levels.
|
||
|
|
Level 0 is a copy of \f2data\fP.
|
||
|
|
The highest level is ${log sub 2}(\f2width\fP)$.
|
||
|
|
For example, if \f2width\fP is 64 and the implementation can store a texture of
|
||
|
|
this size, the following mipmap levels are
|
||
|
|
built: $64 ~times~ 1$, $32 ~times~ 1$, $16 ~times~ 1$, $8 ~times~ 1$,
|
||
|
|
$4 ~times~ 1$, $2 ~times~ 1$ and $1 ~times~ 1$. These correspond to
|
||
|
|
levels 0 through 6, respectively.
|
||
|
|
.P
|
||
|
|
See the \f3glTexImage1D\fP reference page for a description of the
|
||
|
|
acceptable values for the \f2type\fP parameter. See the \f3glDrawPixels\fP
|
||
|
|
reference page for a description of the acceptable values
|
||
|
|
for the \f2data\fP parameter.
|
||
|
|
.SH NOTES
|
||
|
|
Note that there is no direct way of querying the maximum level. This can
|
||
|
|
be derived indirectly via \f3glGetTexLevelParameter\fP. First, query
|
||
|
|
for the
|
||
|
|
width actually used at level 0.
|
||
|
|
(The width may not be equal to \f2width\fP since
|
||
|
|
proxy textures might have scaled it to fit the implementation.)
|
||
|
|
Then the maximum
|
||
|
|
level can be derived from the formula ${log sub 2}(\f2width\fP)$.
|
||
|
|
.P
|
||
|
|
Formats \%\f3GL_BGR\fP, and \%\f3GL_BGRA\fP, and types
|
||
|
|
\%\f3GL_UNSIGNED_BYTE_3_3_2\fP,
|
||
|
|
\%\f3GL_UNSIGNED_BYTE_2_3_3_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_5_6_5\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_5_6_5_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_4_4_4_4\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_4_4_4_4_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_5_5_5_1\fP,
|
||
|
|
\%\f3GL_UNSIGNED_SHORT_1_5_5_5_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_INT_8_8_8_8\fP,
|
||
|
|
\%\f3GL_UNSIGNED_INT_8_8_8_8_REV\fP,
|
||
|
|
\%\f3GL_UNSIGNED_INT_10_10_10_2\fP, and
|
||
|
|
\%\f3GL_UNSIGNED_INT_2_10_10_10_REV\fP are only available if the GL version
|
||
|
|
is 1.2 or greater, and if the GLU version is 1.3 or greater.
|
||
|
|
.SH ERRORS
|
||
|
|
\%\f3GLU_INVALID_VALUE\fP is returned if \f2width\fP is < 1.
|
||
|
|
.P
|
||
|
|
\%\f3GLU_INVALID_ENUM\fP is returned if \f2format\fP or \f2type\fP are not legal.
|
||
|
|
.P
|
||
|
|
\%\f3GLU_INVALID_OPERATION\fP is returned if \f2type\fP is \%\f3GL_UNSIGNED_BYTE_3_3_2\fP or \%\f3GL_UNSIGNED_BYTE_2_3_3_REV\fP
|
||
|
|
and \f2format\fP is not \%\f3GL_RGB\fP.
|
||
|
|
.P
|
||
|
|
\%\f3GLU_INVALID_OPERATION\fP is returned if \f2type\fP is \%\f3GL_UNSIGNED_SHORT_5_6_5\fP or \%\f3GL_UNSIGNED_SHORT_5_6_5_REV\fP
|
||
|
|
and \f2format\fP is not \%\f3GL_RGB\fP.
|
||
|
|
.P
|
||
|
|
\%\f3GLU_INVALID_OPERATION\fP is returned if \f2type\fP is \%\f3GL_UNSIGNED_SHORT_4_4_4_4\fP or \%\f3GL_UNSIGNED_SHORT_4_4_4_4_REV\fP
|
||
|
|
and \f2format\fP is neither \%\f3GL_RGBA\fP nor \%\f3GL_BGRA\fP.
|
||
|
|
.P
|
||
|
|
\%\f3GLU_INVALID_OPERATION\fP is returned if \f2type\fP is \%\f3GL_UNSIGNED_SHORT_5_5_5_1\fP or \%\f3GL_UNSIGNED_SHORT_1_5_5_5_REV\fP
|
||
|
|
and \f2format\fP is neither \%\f3GL_RGBA\fP nor \%\f3GL_BGRA\fP.
|
||
|
|
.P
|
||
|
|
\%\f3GLU_INVALID_OPERATION\fP is returned if \f2type\fP is \%\f3GL_UNSIGNED_INT_8_8_8_8\fP or \%\f3GL_UNSIGNED_INT_8_8_8_8_REV\fP
|
||
|
|
and \f2format\fP is neither \%\f3GL_RGBA\fP nor \%\f3GL_BGRA\fP.
|
||
|
|
.P
|
||
|
|
\%\f3GLU_INVALID_OPERATION\fP is returned if \f2type\fP is \%\f3GL_UNSIGNED_INT_10_10_10_2\fP or \%\f3GL_UNSIGNED_INT_2_10_10_10_REV\fP
|
||
|
|
and \f2format\fP is neither \%\f3GL_RGBA\fP nor \%\f3GL_BGRA\fP.
|
||
|
|
.SH SEE ALSO
|
||
|
|
\f3glDrawPixels(3G)\fP,
|
||
|
|
\f3glTexImage1D(3G)\fP,
|
||
|
|
\f3glTexImage2D(3G)\fP,
|
||
|
|
\f3glTexImage3D(3G)\fP,
|
||
|
|
\%\f3gluBuild2DMipmaps(3G)\fP,
|
||
|
|
\%\f3gluBuild3DMipmaps(3G)\fP,
|
||
|
|
\%\f3gluErrorString(3G)\fP,
|
||
|
|
\f3glGetTexImage(3G)\fP,
|
||
|
|
\f3glGetTexLevelParameter(3G)\fP,
|
||
|
|
\%\f3gluBuild1DMipmapLevels(3G)\fP,
|
||
|
|
\%\f3gluBuild2DMipmapLevels(3G)\fP,
|
||
|
|
\%\f3gluBuild3DMipmapLevels(3G)\fP
|