gluBuild3DMipmaps(3G) OpenGL Reference gluBuild3DMipmaps(3G)
gluBuild3DMipmaps - builds a three-dimensional mipmap
GLint gluBuild3DMipmaps( GLenum target,
GLint internalFormat,
GLsizei width,
GLsizei height,
GLsizei depth,
GLenum format,
GLenum type,
const void *data )
target Specifies the target texture. Must be GL_TEXTURE_3D.
internalFormat Requests the internal storage format of the texture
image. Must be 1, 2, 3, 4, or one of the following
symbolic constants: GL_ALPHA, GL_ALPHA4, GL_ALPHA8,
GL_ALPHA12, GL_ALPHA16, GL_LUMINANCE, GL_LUMINANCE4,
GL_LUMINANCE8, GL_LUMINANCE12, GL_LUMINANCE16,
GL_LUMINANCE_ALPHA, GL_LUMINANCE4_ALPHA4,
GL_LUMINANCE6_ALPHA2, GL_LUMINANCE8_ALPHA8,
GL_LUMINANCE12_ALPHA4, GL_LUMINANCE12_ALPHA12,
GL_LUMINANCE16_ALPHA16, GL_INTENSITY, GL_INTENSITY4,
GL_INTENSITY8, GL_INTENSITY12, GL_INTENSITY16, GL_RGB,
GL_R3_G3_B2, GL_RGB4, GL_RGB5, GL_RGB8, GL_RGB10,
GL_RGB12, GL_RGB16, GL_RGBA, GL_RGBA2, GL_RGBA4,
GL_RGB5_A1, GL_RGBA8, GL_RGB10_A2, GL_RGBA12, or
GL_RGBA16.
width, height, depth
Specifies in pixels the width, height and depth
respectively, in pixels of the texture image.
format Specifies the format of the pixel data. Must be one of
GL_COLOR_INDEX, GL_DEPTH_COMPONENT, GL_RED, GL_GREEN,
GL_BLUE, GL_ALPHA, GL_RGB, GL_RGBA, GL_BGR, GL_BGRA,
GL_LUMINANCE, or GL_LUMINANCE_ALPHA.
type Specifies the data type for data. Must be one of:
GL_UNSIGNED_BYTE, GL_BYTE, GL_BITMAP, GL_UNSIGNED_SHORT,
GL_SHORT, GL_UNSIGNED_INT, GL_INT, GL_FLOAT,
GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV,
GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
GL_UNSIGNED_INT_10_10_10_2, or
GL_UNSIGNED_INT_2_10_10_10_REV.
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gluBuild3DMipmaps(3G) OpenGL Reference gluBuild3DMipmaps(3G)
data Specifies a pointer to the image data in memory.
gluBuild3DMipmaps builds a series of prefiltered three-dimensional
texture maps of decreasing resolutions called a mipmap. This is used for
the antialiasing of texture-mapped primitives.
A return value of zero indicates success, otherwise a GLU error code is
returned (see gluErrorString).
Initially, the width, height and depth of data are checked to see if they
are a power of 2. If not, a copy of data (not data), is scaled up or down
to the nearest power of 2. (If width, height or depth is exactly between
powers of 2, then the copy of data will scale upwards.) This copy will be
used for subsequent mipmapping operations described below. For example,
if width is 57, height is 23 and depth is 24 then a copy of data will
scale up to 64 in width, down to 16 in height and up to 32 in depth,
before mipmapping takes place.
Then, proxy textures (see glTexImage3D) are used to determine if the
implementation can fit the requested texture. If not, all three
dimensions are continually halved until it fits.
Next, a series of mipmap levels is built by decimating a copy of data in
half along all three dimensions until size 1 x 1 x 1 is reached. At each
level, each texel in the halved mipmap level is an average of the
corresponding eight texels in the larger mipmap level. (If exactly one of
the dimensions is 1, four texels are averaged. If exactly two of the
dimensions are 1, two texels are averaged.)
glTexImage3D is called to load each of these mipmap levels. Level 0 is a
copy of data. The highest level is log (max(width,height,depth)). For
example, if width is 64, height is 16 and depth is 32, and the
implementation can store a texture of this size, the following mipmap
levels are built: 64 x 16 x 32, 32 x 8 x 16, 16 x 4 x 8, 8 x 2 x 4,
4 x 1 x 2, 2 x 1 x 1 and 1 x 1 x 1. These correspond to levels 0 through
6, respectively.
See the glTexImage1D reference page for a description of the acceptable
values for format parameter. See the glDrawPixels reference page for a
description of the acceptable values for type parameter.
Note that there is no direct way of querying the maximum level. This can
be derived indirectly via glGetTexLevelParameter. First, query for the
width, height and depth actually used at level 0. (The width, height and
depth may not be equal to width, height and depth respectively since
proxy textures might have scaled them to fit the implementation.) Then
the maximum level can be derived from the formula
log (max(width,height,depth)).
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gluBuild3DMipmaps(3G) OpenGL Reference gluBuild3DMipmaps(3G)
gluBuild3DMipmaps is only available if the GLU version is 1.3 or greater.
Formats GL_BGR, and GL_BGRA, and types GL_UNSIGNED_BYTE_3_3_2,
GL_UNSIGNED_BYTE_2_3_3_REV, GL_UNSIGNED_SHORT_5_6_5,
GL_UNSIGNED_SHORT_5_6_5_REV, GL_UNSIGNED_SHORT_4_4_4_4,
GL_UNSIGNED_SHORT_4_4_4_4_REV, GL_UNSIGNED_SHORT_5_5_5_1,
GL_UNSIGNED_SHORT_1_5_5_5_REV, GL_UNSIGNED_INT_8_8_8_8,
GL_UNSIGNED_INT_8_8_8_8_REV, GL_UNSIGNED_INT_10_10_10_2, and
GL_UNSIGNED_INT_2_10_10_10_REV are only available if the GL version is
1.2 or greater.
GLU_INVALID_VALUE is returned if width, height, or depth is < 1.
GLU_INVALID_ENUM is returned if internalFormat, format, or type is not
legal.
GLU_INVALID_OPERATION is returned if type is GL_UNSIGNED_BYTE_3_3_2 or
GL_UNSIGNED_BYTE_2_3_3_REV and format is not GL_RGB.
GLU_INVALID_OPERATION is returned if type is GL_UNSIGNED_SHORT_5_6_5 or
GL_UNSIGNED_SHORT_5_6_5_REV and format is not GL_RGB.
GLU_INVALID_OPERATION is returned if type is GL_UNSIGNED_SHORT_4_4_4_4 or
GL_UNSIGNED_SHORT_4_4_4_4_REV and format is neither GL_RGBA nor GL_BGRA.
GLU_INVALID_OPERATION is returned if type is GL_UNSIGNED_SHORT_5_5_5_1 or
GL_UNSIGNED_SHORT_1_5_5_5_REV and format is neither GL_RGBA nor GL_BGRA.
GLU_INVALID_OPERATION is returned if type is GL_UNSIGNED_INT_8_8_8_8 or
GL_UNSIGNED_INT_8_8_8_8_REV and format is neither GL_RGBA nor GL_BGRA.
GLU_INVALID_OPERATION is returned if type is GL_UNSIGNED_INT_10_10_10_2
or GL_UNSIGNED_INT_2_10_10_10_REV and format is neither GL_RGBA nor
GL_BGRA.
glDrawPixels, glTexImage1D, glTexImage2D, glTexImage3D,
gluBuild1DMipmaps, gluBuild3DMipmaps, gluErrorString, glGetTexImage,
glGetTexLevelParameter, gluBuild1DMipmapLevels, gluBuild2DMipmapLevels,
gluBuild3DMipmapLevels
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