GLAPI/glCopyTexImage2D

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glCopyTexImage2D
Core in version 4.4
Core since version 1.0

glCopyTexImage2D: copy pixels into a 2D texture image

Function Definition

 void glCopyTexImage2D(GLenum target​, GLint level​, GLenum internalformat​, GLint x​, GLint y​, GLsizei width​, GLsizei height​, GLint border​);
target
Specifies the target texture. Must be GL_TEXTURE_2D​, GL_TEXTURE_CUBE_MAP_POSITIVE_X​, GL_TEXTURE_CUBE_MAP_NEGATIVE_X​, GL_TEXTURE_CUBE_MAP_POSITIVE_Y​, GL_TEXTURE_CUBE_MAP_NEGATIVE_Y​, GL_TEXTURE_CUBE_MAP_POSITIVE_Z​, or GL_TEXTURE_CUBE_MAP_NEGATIVE_Z​.
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 internal format of 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_STENCIL_INDEX8​, GL_RED​, GL_RG​, GL_RGB​, GL_R3_G3_B2​, 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​.
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 image.
height
Specifies the height of the texture image.
border
This value must be 0.

Description

glCopyTexImage2D defines a two-dimensional texture image, or cube-map texture image with pixels from the current GL_READ_BUFFER​.

The screen-aligned pixel rectangle with lower left corner at (x​, y​) and with a width of width​ and a height of height​ defines the texture array at the mipmap level specified by level​. internalformat​ specifies the internal format of the texture array.

The pixels in the rectangle are processed exactly as if glReadPixels 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 and y screen coordinates correspond to lower s and t 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.

When internalformat​ is one of the sRGB types, the GL does not automatically convert the source pixels to the sRGB color space. In this case, the glPixelMap function can be used to accomplish the conversion.

Notes

1, 2, 3, and 4 are not accepted values for internalformat​.

An image with height or width of 0 indicates a NULL texture.

GL_STENCIL_INDEX8​ is accepted for internalformat​ only if the GL version is 4.4 or higher.

Errors

GL_INVALID_ENUM​ is generated if target​ is not GL_TEXTURE_2D​, GL_TEXTURE_CUBE_MAP_POSITIVE_X​, GL_TEXTURE_CUBE_MAP_NEGATIVE_X​, GL_TEXTURE_CUBE_MAP_POSITIVE_Y​, GL_TEXTURE_CUBE_MAP_NEGATIVE_Y​, GL_TEXTURE_CUBE_MAP_POSITIVE_Z​, or GL_TEXTURE_CUBE_MAP_NEGATIVE_Z​.

GL_INVALID_VALUE​ is generated if level​ is less than 0.

GL_INVALID_VALUE​ may be generated if level​ is greater than log2(max}, where max is the returned value of GL_MAX_TEXTURE_SIZE​.

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

GL_INVALID_VALUE​ is generated if border​ is not 0.

GL_INVALID_VALUE​ is generated if internalformat​ is not an accepted format.

GL_INVALID_OPERATION​ is generated if internalformat​ includes a depth component and the current Framebuffer has no depth buffer.

GL_INVALID_OPERATION​ is generated if internalformat​ is a non-normalized integer format and the current read color buffer does not use an integer format.

GL_INVALID_OPERATION​ is generated if internalformat​ is a floating-point or normalized integer format, and the current read color buffer does not use a floating-point or normalized integer format.


Associated Gets

glGetTexImage

See Also

glActiveTexture, glBindTexture, glBindFramebuffer, glCopyTexImage1D, glCopyImageSubData, glCopyTexSubImage1D, glCopyTexSubImage2D, glReadBuffer

Copyright

Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2012-2013 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.