1GL_EXT_subtexture 2https://www.khronos.org/registry/OpenGL/extensions/EXT/EXT_subtexture.txt 3GL_EXT_subtexture 4 5 void glTexSubImage1DEXT (GLenum target, GLint level, GLint xoffset, GLsizei width, GLenum format, GLenum type, const void *pixels) 6 void glTexSubImage2DEXT (GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, const void *pixels) 7 void glTexSubImage3DEXT (GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, const void *pixels) 8