glPixelStorei(GL_UNPACK_ROW_LENGTH, pitch);
check_error();
glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));
glPixelStorei(GL_UNPACK_ROW_LENGTH, pitch);
check_error();
glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width, height, format, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));