fglCopyTexImage1DEXT(3G) OpenGL Reference fglCopyTexImage1DEXT(3G)NAME
fglCopyTexImage1DEXT - copy pixels into a 1D texture image
FORTRAN SPECIFICATION
SUBROUTINE fglCopyTexImage1DEXT( INTEGER*4 target,
INTEGER*4 level,
INTEGER*4 internalformat,
INTEGER*4 x,
INTEGER*4 y,
INTEGER*4 width,
INTEGER*4 border )
PARAMETERS
target The target texture. Must be GL_TEXTURE_1D
level The level-of-detail number. Level 0 is the base image
level. Level n is the nth mipmap reduction image.
internalformat The internal storage format of the texture image. Must
be one of the following symbolic constants: GL_ALPHA,
GL_ALPHA4_EXT, GL_ALPHA8_EXT, GL_ALPHA12_EXT,
GL_ALPHA16_EXT, GL_LUMINANCE, GL_LUMINANCE4_EXT,
GL_LUMINANCE8_EXT, GL_LUMINANCE12_EXT,
GL_LUMINANCE16_EXT, GL_LUMINANCE_ALPHA,
GL_LUMINANCE4_ALPHA4_EXT, GL_LUMINANCE6_ALPHA2_EXT,
GL_LUMINANCE8_ALPHA8_EXT, GL_LUMINANCE12_ALPHA4_EXT,
GL_LUMINANCE12_ALPHA12_EXT, GL_LUMINANCE16_ALPHA16_EXT,
GL_INTENSITY_EXT, GL_INTENSITY4_EXT, GL_INTENSITY8_EXT,
GL_INTENSITY12_EXT, GL_INTENSITY16_EXT, GL_RGB,
GL_RGB2_EXT, GL_RGB4_EXT, GL_RGB5_EXT, GL_RGB8_EXT,
GL_RGB10_EXT, GL_RGB12_EXT, GL_RGB16_EXT, GL_RGBA,
GL_RGBA2_EXT, GL_RGBA4_EXT, GL_RGB5_A1_EXT, GL_RGBA8_EXT,
GL_RGB10_A2_EXT, GL_RGBA12_EXT, GL_RGBA16_EXT. (Note
that the values 1, 2, 3, and 4, which are accepted by
fglTexImage1D, are not accepted by fglCopyTexImage1DEXT.)
x The x coordinate of the lower-left corner of the pixel
rectangle to be transferred to the texture array.
y The y coordinate of the lower-left corner of the pixel
rectangle to be transferred to the texture array.
width The width of the texture image.
border The border width of the texture. Must be 0 or 1.
DESCRIPTION
fglCopyTexImage1DEXT defines a one-dimensional texture image with pixels
from the current GL_READ_BUFFER (rather than from main memory, as is the
case for fglTexImage1D).
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fglCopyTexImage1DEXT(3G) OpenGL Reference fglCopyTexImage1DEXT(3G)
The screen-aligned pixel rectangle with lower-left corner at (x, y)
having width width+2*border and height 1 is used to define the texture
array at the mipmap level specified by level. The internal format of the
texture array is selected by internalformat.
The pixels in the rectangle are processed exactly as if fglCopyPixels had
been called, but the process stops just before final conversion. At this
point all pixel component values are clamped to the range [0, 1] and then
converted to the texture's internal format for storage in the texel
array.
Pixel ordering is such that lower x screen coordinates correspond to
lower i texture coordinates, and lower y screen coordinates correspond to
lower j texture coordinates.
If any of the pixels within the specified rectangle of the current
GL_READ_BUFFER are outside the window associated with the current
rendering context, then the values obtained for those pixels are
undefined.
NOTES
fglCopyTexImage1DEXT is part of the EXT_copy_texture extension. See
fglIntro for more information about using extensions.
ERRORS
GL_INVALID_ENUM is generated when target is not one of the allowable
values.
GL_INVALID_VALUE is generated if level is less than zero or greater than
log (max), where max is the returned value of GL_MAX_TEXTURE_SIZE.
2
GL_INVALID_VALUE is generated if the specified image is too large.
GL_INVALID_VALUE is generated if width is less than zero, greater than
k
2+GL_MAX_TEXTURE_SIZE, or when width cannot be represented as 2 +2border
for some integer k.
GL_INVALID_VALUE is generated if border is not 0 or 1.
GL_INVALID_VALUE is generated if internalformat is not one of the
allowable values.
GL_INVALID_OPERATION is generated if fglCopyTexImage1DEXT is executed
between the execution of fglBegin and the corresponding execution of
fglEnd.
ASSOCIATED GETS
fglGetTexImage
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fglCopyTexImage1DEXT(3G) OpenGL Reference fglCopyTexImage1DEXT(3G)MACHINE DEPENDENCIES
fglCopyTexImage1D and fglCopyTexImage1DEXT are not supported on
RealityEngine, RealityEngine2, and VTX systems.
On InfiniteReality systems, there is a performance benefit when the width
of the image to be transferred to texture memory is a multiple of 8.
Texture borders are not supported on InfiniteReality systems.
Applications should use borderless textures and GL_CLAMP_TO_EDGE_SGIS
wrap mode.
SEE ALSO
fglTexImage1D, fglCopyTexSubImage1DEXT, fglCopyPixels.
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