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OpenGL 1.1 for AIX: Reference Manual

glTexImage3DEXT Subroutine

Purpose

Specifies a three-dimensional (3D) texture subimage.

Library

OpenGL C bindings library: libGL.a

C Syntax

void glTexImage3DEXT(GLenum target, 
          GLint level, 
          GLint internalformat, 
          GLsizei width, 
          GLsizei height, 
          GLsizei depth,
          GLint border, 
          GLenum format, 
          GLenum type, 
          const GLvoid *pixels)

Parameters

target Specifies the target texture. Must be GL_TEXTURE_3D_EXT or GL_PROXY_TEXTURE_3D_EXT.
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 texture. 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_R3_G3_B2, GL_RGB, 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 Specifies the width of the texture image. Must be 2n + 2 × border for some integer n.
height Specifies the height of the texture image. Must be 2m + 2 × border for some integer m.
depth Specifies the depth of the texture image. Must be 2l + 2 × border for some integer l.
border Specifies the width of the border. Must be either 0 or 1.
format Specifies the format of the pixel data. The following symbolic values are accepted: GL_COLOR_INDEX, GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, GL_RGB, GL_RGBA, GL_LUMINANCE, and *GL_LUMINANCE_ALPHA.
type Specifies the data type of the pixel data. The following symbolic values are accepted: GL_UNSIGNED_BYTE, GL_BYTE, GL_BITMAP, GL_UNSIGNED_SHORT, GL_SHORT, GL_UNSIGNED_INT, GL_INT, and GL_FLOAT.
pixels Specifies a pointer to the image data in memory.

Description

Texturing maps a portion of a specified texture image onto each graphical primitive for which texturing is enabled. To enable and disable three-dimensional texturing, call glEnable and glDisable with argument GL_TEXTURE_3D_EXT.

To define 3D texture images, call glTexImage3DEXT. 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 GL_PROXY_TEXTURE_3D_EXT 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 implementation 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 GL_TEXTURE_3D_EXT, data is read from pixels as a sequence of signed or unsigned bytes, shorts, or longs, or single-precision floating-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 GL_BITMAP, the data is considered as a string of unsigned bytes (and format must be GL_COLOR_INDEX). Each data byte is treated as eight 1-bit elements, with bit ordering determined by GL_UNPACK_LSB_FIRST (see glPixelStore).

The first element corresponds to the lower-left corner of the texture image. Subsequent elements progress left-to-right through the remaining texels in the lowest row of the texture image, and then in successively higher rows of the texture image. The final element corresponds to the upper-right corner of the texture image.

The format parameter determines the composition of each element in pixels. It can assume one of nine symbolic values:

GL_COLOR_INDEX Each element is a single value, a color index. The GL converts 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 GL_INDEX_SHIFT, and added to GL_INDEX_OFFSET (see glPixelTransfer). The resulting index is converted to a set of color components using the GL_PIXEL_MAP_I_TO_R, GL_PIXEL_MAP_I_TO_G, GL_PIXEL_MAP_I_TO_B, and GL_PIXEL_MAP_I_TO_A tables, and clamped to the range [0,1].
GL_RED Each element is a single red component. The GL converts it to floating point and assembles it into an RGBA element by attaching 0.0 for green and blue, and 1.0 for alpha. Each component is then multiplied by the signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the range [0,1] (see glPixelTransfer).
GL_GREEN Each element is a single green component. The GL converts it to floating point and assembles it into an RGBA element by attaching 0.0 for red and blue, and 1.0 for alpha. Each component is then multiplied by the signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the range [0,1] (see glPixelTransfer).
GL_BLUE Each element is a single blue component. The GL converts it to floating point and assembles it into an RGBA element by attaching 0.0 for red and green, and 1.0 for alpha. Each component is then multiplied by the signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the range [0,1] (see glPixelTransfer).
GL_ALPHA Each element is a single alpha component. The GL converts it to floating point and assembles it into an RGBA element by attaching 0.0 for red, green, and blue. Each component is then multiplied by the signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the range [0,1] (see glPixelTransfer).
GL_RGB Each element is an RGB triple. The GL converts it to floating point and assembles it into an RGBA element by attaching 1.0 for alpha. Each component is then multiplied by the signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the range [0,1] (see glPixelTransfer).
GL_RGBA Each element contains all four components. Each *component is multiplied by the signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the range [0,1] (see glPixelTransfer).
GL_LUMINANCE 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 1.0 for alpha. Each component is then multiplied by the signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the range [0,1] (see glPixelTransfer).
GL_LUMINANCE_ALPHA 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 GL_c_SCALE, added to the signed bias GL_c_BIAS, 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 must store the texture at a certain resolution or in a certain format, use internalformat to request the resolution and format. The GL will choose an internal representation that closely approximates that requested by internalformat, but it may not match exactly. (The representations specified by GL_LUMINANCE, GL_LUMINANCE_ALPHA, GL_RGB, and GL_RGBA must match exactly. The numeric values 1, 2, 3, and 4 may also be used to specify the above representations.)

Use the GL_PROXY_TEXTURE_3D_EXT target to try out a resolution and format. The implementation will update and recompute its best match for the requested storage resolution and format. To then query this state, call glGetTexLevelParameter. If the texture cannot be accomodated, 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 GL_STENCIL_INDEX and GL_DEPTH_COMPONENT cannot be used. The glPixelStore and glPixelTransfer modes affect texture images in exactly the way they affect glDrawPixels.

The glTexImage3DEXT subroutine and GL_PROXY_TEXTURE_3D_EXT are available only if the EXT_texture3D extension is supported.

Internal formats other than 1, 2, 3, or 4 may only be used if the GL version is 1.1 or greater.

In GL version 1.1 or greater, pixels may be a null pointer. In this case texture memory is allocated to accomodate a texture of width width and height height. You can then download subtextures to initialize this texture memory. The image is undefined if the user tries to apply an uninitialized portion of the texture image to a primitive.

Format of GL_ABGR_EXT is part of the _extname (EXT_abgr) extension, not part of the core GL command set.

Errors

GL_INVALID_ENUM is generated if target is not GL_TEXTURE_3D_EXT or GL_PROXY_TEXTURE_3D_EXT.

GL_INVALID_ENUM is generated if format is not an accepted format constant. Format constants other than GL_STENCIL_INDEX and GL_DEPTH_COMPONENT are accepted.

GL_INVALID_ENUM is generated if type is not a type constant.

GL_INVALID_ENUM is generated if type is GL_BITMAP and format is not GL_COLOR_INDEX.

GL_INVALID_VALUE is generated if level is less than zero.

GL_INVALID_VALUE may be generated if level is greater than log2(max), where max is the returned value of GL_MAX_3D_TEXTURE_SIZE_EXT.

GL_INVALID_VALUE is generated if internalformat is not 1, 2, 3, 4, or one of the accepted resolution and format symbolic constants.

GL_INVALID_VALUE is generated if width, height, or depth is less than zero or greater than 2 + GL_MAX_3D_TEXTURE_SIZE_EXT, or if either cannot be represented as 2k + 2 × border for some integer value of k.

GL_INVALID_VALUE is generated if border is not 0 or 1.

GL_INVALID_OPERATION is generated if glTexImage3DEXT is executed between the execution of glBegin and the corresponding execution of glEnd.

Associated Gets

glGetTexImage

glIsEnabled with argument GL_TEXTURE_3D_EXT

Related Information

The glCopyTexSubImage3DEXT subroutine, glDrawPixels subroutine, glFog subroutine, glPixelStore subroutine, glPixelTransfer subroutine, glTexEnv subroutine, glTexGen subroutine, glTexImage1D subroutine, glTexParameter subroutine, glTexImage2D subroutine.


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