I made a scan and got a cloud point file, but the cloud point is not that good, but I need to print it in a 3d printer as soon as possible, just to see how it would look.
Basically it's missing some points that were not scanned properly due to it being transparent at those points. I'd like to add those points manually (using meshlab preferably) and create a surface with them .. something that makes this file printable.
I know I could edit this file manually since it is an ascii file with the values of xyz .. but that is a lot of trouble and certainly there is a faster way to do this with a free tool.
A good free tool for editing meshes would be Blender. Linux, Windows, Mac are supported. It has a serious learning curve, and is somewhat counter-intuitive in use (right click object to select) unless you customize it.
Plenty of online video tutorials to learn the basics, though, and if you have a membership for Lynda.com, those videos are the best (opinion).
I've used it to pull edges and vertices together, to chop out pieces that weren't supposed to be there, etc. The flexibility and power of the program is amazing, considering the price.
Many artists use the program for creating 3D animations and full length movies. Amazing talent, well beyond my capabilities, but it shows what the software can do.
The website also has links to tutorials and the manual, which is also a work of art.
If you can devote the time to learn the program, anything 3D modeling related will be within reach.