HP Workstation zx2000 OpenGL 1.1 Reference for HP-UX 11.x - Page 83

Chapter 3 C glCopyTexSubImage2D 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. 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. Notes glCopyTexSubImage2D is available only if the GL version is 1.1 or greater. Texturing has no effect in color index mode. glPixelStore and glPixelTransfer modes affect texture images in exactly the way they affect glDrawPixels. Errors • GL_INVALID_ENUM is generated if target is not GL_TEXTURE_2D. • GL_INVALID_OPERATION is generated if the texture array has not been defined by a previous glTexImage2D or glCopyTexImage2D operation. • 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 x < - b or if y < - b, where b is the border width of the texture array. • GL_INVALID_VALUE is generated if xoffset < - b, (xoffset + width) > (w- b), yoffset < - b, or (yoffset + height) > (h - b), where w is the GL_TEXTURE_WIDTH, h is the GL_TEXTURE_HEIGHT, and b is the GL_TEXTURE_BORDER of the texture image being modified. Note that w and h include twice the border width. • GL_INVALID_OPERATION is generated if glCopyTexSubImage2D is executed between the execution of glBegin and the corresponding execution of glEnd. Associated gets glGetTexImage glIsEnabled with argument GL_TEXTURE_2D See Also glCopyPixels, glCopyTexImage1D, glCopyTexImage2D, glCopyTexSubImage1D, glPixelStore, glPixelTransfer, glTexEnv, glTexGen, glTexImage1D, glTexImage2D, 83