GlCopyTexSubImage2D

_glCopyTexSubImage2D: copy a two-dimensional texture subimage

Syntax

SUB _glCopyTexSubImage2D (BYVAL target AS _UNSIGNED LONG, BYVAL level AS LONG, BYVAL xoffset AS LONG, BYVAL yoffset AS LONG, BYVAL x AS LONG, BYVAL y AS LONG, BYVAL width AS LONG, BYVAL height AS LONG)

void _glCopyTexSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint x, GLint y, GLsizei width, GLsizei height);

target

Specifies the target texture. Must be Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, or Template:KW.

level

Specifies the level-of-detail number. Level 0 is the base image level. Level n is the nth mipmap reduction image.

xoffset

Specifies a texel offset in the x direction within the texture array.

yoffset

Specifies a texel offset in the y direction within the texture array.

x, y

Specify the window coordinates of the lower left corner of the rectangular region of pixels to be copied.

width

Specifies the width of the texture subimage.

height

Specifies the height of the texture subimage.

Description

_glCopyTexSubImage2D replaces a rectangular portion of a two-dimensional texture image, cube-map texture image or a linear portion of a number of slices of a one-dimensional array texture with pixels from the current Template:KW (rather than from main memory, as is the case for Template:KW).

The screen-aligned pixel rectangle with lower left corner at (x, y) and with width width and height height replaces the portion of the texture array with x indices xoffset through xoffset + width - 1, inclusive, and y indices yoffset through yoffset + height - 1, inclusive, at the mipmap level specified by level.

The pixels in the rectangle are processed exactly as if Template:KW 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.

The destination rectangle in the texture array may not include any texels outside the texture array as it was originally specified. It is not an error to specify a subtexture with zero width or height, but such a specification has no effect.

When target is Template:KW then the y coordinate and height are treated as the start slice and number of slices to modify.

If any of the pixels within the specified rectangle of the current Template:KW are outside the read window associated with the current rendering context, then the values obtained for those pixels are undefined.

No change is made to the internalformat, width, height, or border parameters of the specified texture array or to texel values outside the specified subregion.

Template:PageNotes

Template:KW modes affect texture images.

Template:PageErrors

Template:KW is generated if target is not Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, or Template:KW.

Template:KW is generated if the texture array has not been defined by a previous Template:KW or Template:KW operation.

Template:KW is generated if level is less than 0.

Template:KW may be generated if level is greater than log₂(max), where max is the returned value of Template:KW.

Template:KW is generated if xoffset < 0, xoffset + width > w, yoffset < 0, or yoffset + height > h, where w is the Template:KW and h is the Template:KW of the texture image being modified.

Template:PageUseWith

See also

SUB _GL Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, Template:KW, Template:KW

Template:PageCopyright