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GLTEXIMAGE1D(3G)                                 OpenGL 3.3                                 GLTEXIMAGE1D(3G)



NAME
       glTexImage1D - specify a one-dimensional texture image

C SPECIFICATION
       void glTexImage1D(GLenum target, GLint level, GLint internalFormat, GLsizei width, GLint border,
                         GLenum format, GLenum type, const GLvoid * data);


PARAMETERS
       target
           Specifies the target texture. Must be GL_TEXTURE_1D or GL_PROXY_TEXTURE_1D.

       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 one of the following symbolic
           constants: GL_COMPRESSED_RED, GL_COMPRESSED_RG, GL_COMPRESSED_RGB, GL_COMPRESSED_RGBA,
           GL_COMPRESSED_SRGB, GL_COMPRESSED_SRGB_ALPHA, GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16,
           GL_DEPTH_COMPONENT24, GL_DEPTH_COMPONENT32, GL_R3_G3_B2, GL_RED, GL_RG, 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, GL_RGBA16, GL_SRGB, GL_SRGB8, GL_SRGB_ALPHA, or GL_SRGB8_ALPHA8.

       width
           Specifies the width of the texture image. All implementations support texture images that are at
           least 1024 texels wide. The height of the 1D texture image is 1.

       border
           This value must be 0.

       format
           Specifies the format of the pixel data. The following symbolic values are accepted: GL_RED,
           GL_RG, GL_RGB, GL_BGR, GL_RGBA, and GL_BGRA.

       type
           Specifies the data type of the pixel data. The following symbolic values are accepted:
           GL_UNSIGNED_BYTE, GL_BYTE, 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, and GL_UNSIGNED_INT_2_10_10_10_REV.

       data
           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 one-dimensional texturing, call glEnable() and
       glDisable() with argument GL_TEXTURE_1D.

       Texture images are defined with glTexImage1D. The arguments describe the parameters of the texture
       image, such as width, width of the border, level-of-detail number (see glTexParameter()), and the
       internal resolution and format used to store the image. The last three arguments describe how the
       image is represented in memory.

       If target is GL_PROXY_TEXTURE_1D, no data is read from data, 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_1D, data is read from data 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. Each data byte is
       treated as eight 1-bit elements, with bit ordering determined by GL_UNPACK_LSB_FIRST (see
       glPixelStore()).

       If a non-zero named buffer object is bound to the GL_PIXEL_UNPACK_BUFFER target (see glBindBuffer())
       while a texture image is specified, data is treated as a byte offset into the buffer object's data
       store.

       The first element corresponds to the left end of the texture array. Subsequent elements progress
       left-to-right through the remaining texels in the texture array. The final element corresponds to the
       right end of the texture array.


       format determines the composition of each element in data. It can assume one of these symbolic
       values:

       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 for green and blue, and 1 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].

       GL_RG
           Each element is a single red/green double The GL converts it to floating point and assembles it
           into an RGBA element by attaching 0 for blue, and 1 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].

       GL_RGB

       GL_BGR
           Each element is an RGB triple. The GL converts it to floating point and assembles it into an RGBA
           element by attaching 1 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].

       GL_RGBA

       GL_BGRA
           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].

       GL_DEPTH_COMPONENT
           Each element is a single depth value. The GL converts it to floating point, multiplies by the
           signed scale factor GL_DEPTH_SCALE, adds the signed bias GL_DEPTH_BIAS, and clamps to the range
           [0,1].

       If an application wants to store the texture at a certain resolution or in a certain format, it can
       request the resolution and format 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 GL_RED, GL_RG, GL_RGB and GL_RGBA must match exactly.)

       If the internalFormat parameter is one of the generic compressed formats, GL_COMPRESSED_RED,
       GL_COMPRESSED_RG, GL_COMPRESSED_RGB, or GL_COMPRESSED_RGBA, the GL will replace the internal format
       with the symbolic constant for a specific internal format and compress the texture before storage. If
       no corresponding internal format is available, or the GL can not compress that image for any reason,
       the internal format is instead replaced with a corresponding base internal format.

       If the internalFormat parameter is GL_SRGB, GL_SRGB8, GL_SRGB_ALPHAor GL_SRGB8_ALPHA8, the texture is
       treated as if the red, green, or blue components are encoded in the sRGB color space. Any alpha
       component is left unchanged. The conversion from the sRGB encoded component c s to a linear component
       c l is:


       c l = { c s 12.92 if c s ^o 0.04045 ( c s + 0.055 1.055 ) 2.4 if c s > 0.04045

       Assume c s is the sRGB component in the range [0,1].

       Use the GL_PROXY_TEXTURE_1D 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 accommodated, texture state is set to
       0.

       A one-component texture image uses only the red component of the RGBA color from data. 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.

       Image-based shadowing can be enabled by comparing texture r coordinates to depth texture values to
       generate a boolean result. See glTexParameter() for details on texture comparison.

NOTES
       glPixelStore() modes affect texture images.


       data may be a null pointer. In this case texture memory is allocated to accommodate a texture of
       width width. You can then download subtextures to initialize the texture memory. The image is
       undefined if the program tries to apply an uninitialized portion of the texture image to a primitive.


       glTexImage1D specifies the one-dimensional texture for the current texture unit, specified with
       glActiveTexture().

ERRORS
       GL_INVALID_ENUM is generated if target is not GL_TEXTURE_1D or GL_PROXY_TEXTURE_1D.


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


       GL_INVALID_ENUM is generated if type is not a type constant.


       GL_INVALID_VALUE is generated if level is less than 0.


       GL_INVALID_VALUE may be generated if level is greater than log 2 ^, max, where max is the returned
       value of GL_MAX_TEXTURE_SIZE.


       GL_INVALID_VALUE is generated if internalFormat is not one of the accepted resolution and format
       symbolic constants.


       GL_INVALID_VALUE is generated if width is less than 0 or greater than GL_MAX_TEXTURE_SIZE.


       GL_INVALID_VALUE is generated if non-power-of-two textures are not supported and the width cannot be
       represented as 2 n + 2 ^, border for some integer value of n.


       GL_INVALID_VALUE is generated if border is not 0 or 1.


       GL_INVALID_OPERATION is generated if type is one of GL_UNSIGNED_BYTE_3_3_2,
       GL_UNSIGNED_BYTE_2_3_3_REV, GL_UNSIGNED_SHORT_5_6_5, or GL_UNSIGNED_SHORT_5_6_5_REV and format is not
       GL_RGB.


       GL_INVALID_OPERATION is generated if type is one of 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 and format is neither GL_RGBA nor GL_BGRA.


       GL_INVALID_OPERATION is generated if format is GL_DEPTH_COMPONENT and internalFormat is not
       GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32.


       GL_INVALID_OPERATION is generated if internalFormat is GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16,
       GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32, and format is not GL_DEPTH_COMPONENT.


       GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
       GL_PIXEL_UNPACK_BUFFER target and the buffer object's data store is currently mapped.


       GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
       GL_PIXEL_UNPACK_BUFFER target and the data would be unpacked from the buffer object such that the
       memory reads required would exceed the data store size.


       GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the
       GL_PIXEL_UNPACK_BUFFER target and data is not evenly divisible into the number of bytes needed to
       store in memory a datum indicated by type.

ASSOCIATED GETS
       glGetTexImage()


       glGet() with argument GL_PIXEL_UNPACK_BUFFER_BINDING

SEE ALSO
       glActiveTexture(), glCompressedTexImage1D(), glCompressedTexSubImage1D(), glCopyTexImage1D(),
       glCopyTexSubImage1D(), glGetCompressedTexImage(), glPixelStore(), glTexImage2D(), glTexImage3D(),
       glTexSubImage1D(), glTexSubImage2D(), glTexSubImage3D(), glTexParameter()


COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software
       B License. For details, see http://oss.sgi.com/projects/FreeB/.



OpenGL 3.3                                       03/08/2011                                 GLTEXIMAGE1D(3G)