glCopyTexSubImage1DEXT(3G)
glCopyTexSubImage1DEXT - copy pixels into a 1D texture subimage
As shipped in IRIX 6.5. First release of IRIX 6.5.
NAME glCopyTexSubImage1DEXT - copy pixels into a 1D texture subimage C SPECIFICATION void glCopyTexSubImage1DEXT( GLenum target, GLint level, GLint xoffset, GLint x, GLint y, GLsizei width ) 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. xoffset A texel offset in the x direction within the texture array. 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 pixel rectangle to be transferred to the texture array. DESCRIPTION glCopyTexSubImage1DEXT replaces a rectangular portion of a two- dimensional texture image with pixels from the current GL_READ_BUFFER (rather than from main memory, as is the case for glTexSubImage1DEXT). The screen-aligned pixel rectangle with lower-left corner at (x, y), width width and height 1 replaces the portion of the texture array with x indices xoffset through xoffset+width-1, inclusive. The destination rectangle in the texture array may not include any texels outside the texture array as it was originally specified. The pixels in the rectangle are processed exactly as if glCopyPixels 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. It is not an error to specify a subtexture with zero width, but such a specification has no effect. If any of the pixels within the specified rectangle of the current GL_READ_BUFFER are outside the read window associated with the current rendering context, then the values obtained for those pixels are undefined. NOTES glCopyTexSubImage1DEXT is part of the EXT_copy_texture extension. See glIntro 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 xoffset<-TEXTURE_BORDER, or (xoffset+width)>(TEXTURE_WIDTH-TEXTURE_BORDER), where TEXTURE_WIDTH and TEXTURE_BORDER are the state values of the texture image being modified. Note that TEXTURE_WIDTH includes twice the border width. GL_INVALID_VALUE is generated if width is negative. GL_INVALID_OPERATION is generated when the texture array has not been defined by a previous glTexImage1D (or equivalent) operation. GL_INVALID_OPERATION is generated if glCopyTexSubImage1DEXT is executed between the execution of glBegin and the corresponding execution of glEnd. ASSOCIATED GETS glGetTexImage MACHINE DEPENDENCIES glCopyTexSubImage1D and glCopyTexSubImage1DEXT 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. On High Impact and Maximum Impact systems, if the right side of the image to be transferred to texture memory is not the right side of the texture, then its index must be a multiple of 32, where index = xoffset+width. Otherwise it will generate a GL_INVALID_VALUE error. SEE ALSO glTexImage1D, glTexSubImage1DEXT, glCopyPixels.