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OpenGL 1.2 for AIX: Reference Manual

gluBuild3DMipmapLevels Subroutine

Purpose

Builds a subset of 3D mipmap levels.

Library

OpenGL C bindings library: libGL.a

C Syntax

GLint	gluBuild3DMipmapLevels( GLenum target,
   GLint internalFormat,
   GLsizei width,
   GLsizei height,
   GLsizei depth,
   GLenum format,
   GLenum type,
   GLint level,
   GLint base,
   GLint max,
   const void *data )

Description

gluBuild3DMipmapLevels builds a subset of prefiltered 3D texture maps of decreasing resolutions called a mipmap. This is used for the antialiasing of texture mapped primitives.

A return value of 0 indicates success, otherwise a GLU error code is returned (see gluErrorString).

A series of mipmap levels from base to max is built by decimating data in half along both dimensions until size 1x1x1 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 these mipmap levels from base to max. If max is larger than the highest mipmap level for the texture of the specified size, then a GLU error code is returned (see gluErrorString) and nothing is loaded.

For example, if level is 2 and width is 16, height is 8 and depth is 4, the following levels are possible: 16x8x4, 8x4x2, 4x2x1, 2x1x1, 1x1x1. These correspond to levels 2 through 6 respectively. If base is 3 and max is 5, then only mipmap levels 8x4x2, 4x2x1 and 2x1x1 are loaded. However, if max is 7 then an error is returned and nothing is loaded since max is larger than the highest mipmap level which is, in this case, 6.

The highest mipmap level can be derived from the formula log2(max(width,height,depth)*(2^level)).

See the glTexImage1D subroutine for a description of the acceptable values for format parameter. See the glDrawPixels subroutine for a description of the acceptable values for type parameter.

Parameters

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, or 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
  • GL_RGBA16
width Specifies the width, in pixels, of the texture image. These should be a power of 2.
height Specifies the height, in pixels, of the texture image. These should be a power of 2.
depth Specifies the depth, in pixels, of the texture image. These should be a power of 2.
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_BGRA
  • GL_LUMINANCE
  • 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
  • GL_UNSIGNED_INT_2_10_10_10_REV
level Specifies the mipmap level of the image data.
base Specifies the minimum mipmap level to pass to glTexImage3D.
max Specifies the maximum mipmap level to pass to glTexImage3D.
data Specifies a pointer to the image data in memory.

Error Codes

GLU_INVALID_VALUE is returned if level > base, base < 0, max < base or max is > the highest mipmap level for data.

GLU_INVALID_VALUE is returned if width, height or depth are < 1.

GLU_INVALID_ENUM is returned if internalFormat, format or type are 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.

Files

/usr/include/GL/gl.h Contains C language constraints, variable type definitions, and ANSI function prototypes for OpenGL.

Related Information

glDrawPixels subroutine, glTexImage1D subroutine, glTexImage2D subroutine, glTexImage3D subroutine, gluBuild1DMipmaps subroutine, gluBuild2DMipmaps subroutine, gluBuild3DMipmaps subroutine, gluErrorString subroutine, glGetTexImage subroutine, glGetTexLevelParameter subroutine, gluBuild1DMipmapLevels subroutine, gluBuild2DMipmapLevels subroutine.


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