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<STRONG>NAME</STRONG>
<STRONG>glTexImage1D</STRONG> - specify a one-dimensional texture image
<STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
void <STRONG>glTexImage1D</STRONG>( GLenum <EM>target</EM>,
GLint <EM>level</EM>,
GLint <EM>internalformat</EM>,
GLsizei <EM>width</EM>,
GLint <EM>border</EM>,
GLenum <EM>format</EM>,
GLenum <EM>type</EM>,
const GLvoid *<EM>pixels</EM> )
<STRONG>PARAMETERS</STRONG>
<EM>target</EM> Specifies the target texture. Must be
<STRONG>GL_TEXTURE_1D</STRONG> or <STRONG>GL_PROXY_TEXTURE_1D</STRONG>.
<EM>level</EM> Specifies the level-of-detail number. Level
0 is the base image level. Level <EM>n</EM> is the
<EM>n</EM>th mipmap reduction image.
<EM>internalformat</EM> Specifies the number of color components in
the texture. Must be 1, 2, 3, or 4, or one
of the following symbolic constants:
<STRONG>GL_ALPHA</STRONG>, <STRONG>GL_ALPHA4</STRONG>, <STRONG>GL_ALPHA8</STRONG>, <STRONG>GL_ALPHA12</STRONG>,
<STRONG>GL_ALPHA16</STRONG>, <STRONG>GL_LUMINANCE</STRONG>, <STRONG>GL_LUMINANCE4</STRONG>,
<STRONG>GL_LUMINANCE8</STRONG>, <STRONG>GL_LUMINANCE12</STRONG>,
<STRONG>GL_LUMINANCE16</STRONG>, <STRONG>GL_LUMINANCE_ALPHA</STRONG>,
<STRONG>GL_LUMINANCE4_ALPHA4</STRONG>, <STRONG>GL_LUMINANCE6_ALPHA2</STRONG>,
<STRONG>GL_LUMINANCE8_ALPHA8</STRONG>, <STRONG>GL_LUMINANCE12_ALPHA4</STRONG>,
<STRONG>GL_LUMINANCE12_ALPHA12</STRONG>,
<STRONG>GL_LUMINANCE16_ALPHA16</STRONG>, <STRONG>GL_INTENSITY</STRONG>,
<STRONG>GL_INTENSITY4</STRONG>, <STRONG>GL_INTENSITY8</STRONG>,
<STRONG>GL_INTENSITY12</STRONG>, <STRONG>GL_INTENSITY16</STRONG>, <STRONG>GL_RGB</STRONG>,
<STRONG>GL_R3_G3_B2</STRONG>, <STRONG>GL_RGB4</STRONG>, <STRONG>GL_RGB5</STRONG>, <STRONG>GL_RGB8</STRONG>,
<STRONG>GL_RGB10</STRONG>, <STRONG>GL_RGB12</STRONG>, <STRONG>GL_RGB16</STRONG>, <STRONG>GL_RGBA</STRONG>,
<STRONG>GL_RGBA2</STRONG>, <STRONG>GL_RGBA4</STRONG>, <STRONG>GL_RGB5_A1</STRONG>, <STRONG>GL_RGBA8</STRONG>,
<STRONG>GL_RGB10_A2</STRONG>, <STRONG>GL_RGBA12</STRONG>, or <STRONG>GL_RGBA16</STRONG>.
<EM>width</EM> Specifies the width of the texture image.
Must be 2n+2(border) for some integer n. All
implementations support texture images that
are at least 64 texels wide. The height of
the 1D texture image is 1.
<EM>border</EM> Specifies the width of the border. Must be
either 0 or 1.
<EM>format</EM> Specifies the format of the pixel data. The
following symbolic values are accepted:
<STRONG>GL_COLOR_INDEX</STRONG>, <STRONG>GL_RED</STRONG>, <STRONG>GL_GREEN</STRONG>, <STRONG>GL_BLUE</STRONG>,
<STRONG>GL_ALPHA</STRONG>, <STRONG>GL_RGB</STRONG>, <STRONG>GL_RGBA</STRONG>, <STRONG>GL_LUMINANCE</STRONG>, and
<STRONG>GL_LUMINANCE_ALPHA</STRONG>.
<EM>type</EM> Specifies the data type of the pixel data.
The following symbolic values are accepted:
<STRONG>GL_UNSIGNED_BYTE</STRONG>, <STRONG>GL_BYTE</STRONG>, <STRONG>GL_BITMAP</STRONG>,
<STRONG>GL_UNSIGNED_SHORT</STRONG>, <STRONG>GL_SHORT</STRONG>,
<STRONG>GL_UNSIGNED_INT</STRONG>, <STRONG>GL_INT</STRONG>, and <STRONG>GL_FLOAT</STRONG>.
<EM>pixels</EM> Specifies a pointer to the image data in
memory.
<STRONG>DESCRIPTION</STRONG>
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 <STRONG>glEnable</STRONG>
and <STRONG>glDisable</STRONG> with argument <STRONG>GL_TEXTURE_1D</STRONG>.
Texture images are defined with <STRONG>glTexImage1D</STRONG>. The arguments
describe the parameters of the texture image, such as width,
width of the border, level-of-detail number (see
<STRONG>glTexParameter</STRONG>), and the internal resolution and format used
to store the image. The last three arguments describe how
the image is represented in memory; they are identical to
the pixel formats used for <STRONG>glDrawPixels</STRONG>.
If <EM>target</EM> is <STRONG>GL_PROXY_TEXTURE_1D</STRONG>, no data is read from
<EM>pixels</EM>, 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
<STRONG>glGetError</STRONG>). To query for an entire mipmap array, use an
image array level greater than or equal to 1.
If <EM>target</EM> is <STRONG>GL_TEXTURE_1D</STRONG>, data is read from <EM>pixels</EM> as a
sequence of signed or unsigned bytes, shorts, or longs, or
single-precision floating-point values, depending on <EM>type</EM>.
These values are grouped into sets of one, two, three, or
four values, depending on <EM>format</EM>, to form elements. If <EM>type</EM>
is <STRONG>GL_BITMAP</STRONG>, the data is considered as a string of unsigned
bytes (and <EM>format</EM> must be <STRONG>GL_COLOR_INDEX</STRONG>). Each data byte is
treated as eight 1-bit elements, with bit ordering
determined by <STRONG>GL_UNPACK_LSB_FIRST</STRONG> (see <STRONG>glPixelStore</STRONG>).
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.
<EM>format</EM> determines the composition of each element in <EM>pixels</EM>.
It can assume one of nine symbolic values:
<STRONG>GL_COLOR_INDEX</STRONG>
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 <STRONG>GL_INDEX_SHIFT</STRONG>, and added to
<STRONG>GL_INDEX_OFFSET</STRONG> (see <STRONG>glPixelTransfer</STRONG>). The
resulting index is converted to a set of color
components using the <STRONG>GL_PIXEL_MAP_I_TO_R</STRONG>,
<STRONG>GL_PIXEL_MAP_I_TO_G</STRONG>, <STRONG>GL_PIXEL_MAP_I_TO_B</STRONG>, and
<STRONG>GL_PIXEL_MAP_I_TO_A</STRONG> tables, and clamped to the
range [0,1].
<STRONG>GL_RED</STRONG> 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 <STRONG>GL_c_SCALE</STRONG>,
added to the signed bias <STRONG>GL_c_BIAS</STRONG>, and clamped to
the range [0,1] (see <STRONG>glPixelTransfer</STRONG>).
<STRONG>GL_GREEN</STRONG> Each element is a single green component. The GL
converts it to floating point and assembles it
into an RGBA element by attaching 0 for red and
blue, and 1 for alpha. Each component is then
multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,
added to the signed bias <STRONG>GL_c_BIAS</STRONG>, and clamped to
the range [0,1] (see <STRONG>glPixelTransfer</STRONG>).
<STRONG>GL_BLUE</STRONG> Each element is a single blue component. The GL
converts it to floating point and assembles it
into an RGBA element by attaching 0 for red and
green, and 1 for alpha. Each component is then
multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,
added to the signed bias <STRONG>GL_c_BIAS</STRONG>, and clamped to
the range [0,1] (see <STRONG>glPixelTransfer</STRONG>).
<STRONG>GL_ALPHA</STRONG> Each element is a single alpha component. The GL
converts it to floating point and assembles it
into an RGBA element by attaching 0 for red,
green, and blue. Each component is then
multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,
added to the signed bias <STRONG>GL_c_BIAS</STRONG>, and clamped to
the range [0,1] (see <STRONG>glPixelTransfer</STRONG>).
<STRONG>GL_RGB</STRONG> 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
<STRONG>GL_c_SCALE</STRONG>, added to the signed bias <STRONG>GL_c_BIAS</STRONG>,
and clamped to the range [0,1] (see
<STRONG>glPixelTransfer</STRONG>).
<STRONG>GL_RGBA</STRONG> Each element contains all four components. Each
component is then multiplied by the signed scale
factor <STRONG>GL_c_SCALE</STRONG>, added to the signed bias
<STRONG>GL_c_BIAS</STRONG>, and clamped to the range [0,1] (see
<STRONG>glPixelTransfer</STRONG>).
<STRONG>GL_LUMINANCE</STRONG>
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 for alpha. Each component is then
multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,
added to the signed bias <STRONG>GL_c_BIAS</STRONG>, and clamped to
the range [0,1] (see <STRONG>glPixelTransfer</STRONG>).
<STRONG>GL_LUMINANCE_ALPHA</STRONG>
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 <STRONG>GL_c_SCALE</STRONG>, added to the signed bias
<STRONG>GL_c_BIAS</STRONG>, and clamped to the range [0,1] (see
<STRONG>glPixelTransfer</STRONG>).
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 <EM>internalformat</EM>. The GL will
choose an internal representation that closely approximates
that requested by <EM>internalformat</EM>, but it may not match
exactly. (The representations specified by <STRONG>GL_LUMINANCE</STRONG>,
<STRONG>GL_LUMINANCE_ALPHA</STRONG>, <STRONG>GL_RGB</STRONG>, and <STRONG>GL_RGBA</STRONG> must match exactly.
The numeric values 1, 2, 3, and 4 may also be used to
specify the preceding representations.)
Use the <STRONG>GL_PROXY_TEXTURE_1D</STRONG> 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 query this state, call <STRONG>glGetTexLevelParameter</STRONG>. 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 extracted from <EM>pixels</EM>. 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.
<STRONG>NOTES</STRONG>
Texturing has no effect in color index mode.
The texture image can be represented by the same data
formats as the pixels in a <STRONG>glDrawPixels</STRONG> command, except that
<STRONG>GL_STENCIL_INDEX</STRONG> and <STRONG>GL_DEPTH_COMPONENT</STRONG> cannot be used.
<STRONG>glPixelStore</STRONG> and <STRONG>glPixelTransfer</STRONG> modes affect texture images
in exactly the way they affect <STRONG>glDrawPixels</STRONG>.
<STRONG>GL_PROXY_TEXTURE_1D</STRONG> may only be used if the GL version is
1.1 or greater.
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, <EM>pixels</EM> may be a null pointer.
In this case texture memory is allocated to accommodate a
texture of width <EM>width</EM>. 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.
<STRONG>ERRORS</STRONG>
<STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>target</EM> is not <STRONG>GL_TEXTURE_1D</STRONG>
or <STRONG>GL_PROXY_TEXTURE_1D</STRONG>.
<STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>format</EM> is not an accepted
format constant. Format constants other than
<STRONG>GL_STENCIL_INDEX</STRONG> and <STRONG>GL_DEPTH_COMPONENT</STRONG> are accepted.
<STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>type</EM> is not a type constant.
<STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>type</EM> is <STRONG>GL_BITMAP</STRONG> and <EM>format</EM>
is not <STRONG>GL_COLOR_INDEX</STRONG>.
<STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>level</EM> is less than 0.
<STRONG>GL_INVALID_VALUE</STRONG> may be generated if <EM>level</EM> is greater than
log <EM>max</EM>, where <EM>max</EM> is the returned value of
<STRONG>GL_MAX_TEXTURE_SIZE</STRONG>.
<STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>internalformat</EM> is not 1, 2,
3, 4, or one of the accepted resolution and format symbolic
constants.
<STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>width</EM> is less than 0 or
greater than 2 + <STRONG>GL_MAX_TEXTURE_SIZE</STRONG>, or if it cannot be
represented as 2n+2(border) for some integer value of <EM>n</EM>.
<STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>border</EM> is not 0 or 1.
<STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glTexImage1D</STRONG> is
executed between the execution of <STRONG>glBegin</STRONG> and the
corresponding execution of <STRONG>glEnd</STRONG>.
<STRONG>ASSOCIATED</STRONG> <STRONG>GETS</STRONG>
<STRONG>glGetTexImage</STRONG> <STRONG>glIsEnabled</STRONG> with argument <STRONG>GL_TEXTURE_1D</STRONG>
<STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
<STRONG>glCopyPixels</STRONG>, <STRONG>glCopyTexImage1D</STRONG>, <STRONG>glCopyTexImage2D</STRONG>,
<STRONG>glCopyTexSubImage1D</STRONG>, <STRONG>glCopyTexSubImage2D</STRONG>, <STRONG>glDrawPixels</STRONG>,
<STRONG>glPixelStore</STRONG>, <STRONG>glPixelTransfer</STRONG>, <STRONG>glTexEnv</STRONG>, <STRONG>glTexGen</STRONG>,
<STRONG>glTexImage2D</STRONG>, <STRONG>glTexSubImage1D</STRONG>, <STRONG>glTexSubImage2D</STRONG>,
<STRONG>glTexParameter</STRONG>
</PRE>
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