Hi guys;
 
	There are some nodes in called "Texture 3D VOP node", "Texture 3D Box " , "Gradient 3D" and so on...
 
	https://www.sidefx.com/docs/houdini/nodes/vop/texture3d.html
 
	 
 
	According to docs: This operator returns the value of a 3D image at a specified position within that image.
 
	So what is a "3D image " ? and in which context should we use them?
 
	 
 
	 
 
	Thanks.