I wish to again express that Punch/Shark need a new way to help the user calculate usable volume of not just a solid, but a general shape.

Let me bring up a comparison: Freeship Plus/Hydronship 3.30.

I Freeship, I can take 8 points to make the boundaries of sideshell of a vessel, positioned such that they make a wall or plate representative of the side of the vessel. I select them and click a 'surface' tool. I have the sideshell/plating, mostly convex or concave, depending on how you look at it.

I select the upper edge and extrude it inward to get the upper deck. I select the fore and aft edges of plate/sideshell inboard to get bulkheads.

The program already knows (or assumes unless I override) that the hull compartment or hull is symmetrical. If I change the draft (water draft, nothing to do with CAD/angles/draft/take-offs) to be almost near the top without totally submerging the body, I can run a report and obtain the volume of that compartment.

I cannot do this in either VCP or Shark. It would be really nice to *NOT* have to turn a volume into a solid when trying to very quickly find out what useable volume is in a region of the model. I might want to know volume to calculate air changes. It could be for estimating the number of pallets or cases of food or supplies or other stuff to be put into an area. It could be a ship, a sub, air airplane, a boat, a car trunk/boot, or a subterranean home. In the case of a subterranean home, it would be immensely useful to report how many dump truck loads (cubic yards, cubic feet, cubic meters) of dirt will be hauled away, exchanged, or repacked around the construction site.

A couple of years ago, I posited this request, and the response was that it takes a lot of code or effort, and that the model has to be sealed. That, I beg to say, is asking a lot of the users to forfeit the power of a CPU and a GPU that can in 3 seconds do it right, the first time.

A user should be able to draw a square, a sphere, or a quasi-hugging, non-poked balloon/bubble around objects and know the volume. Whether one is modeling pipes, Slinky's, or intestines (yeh, yuck!), it should be possible nearly-instantly get the volume -- even if there is risk of "self intersections" (please tell Spatial this!).

So, what is 3M, 45-258kb?

3.2 MB is the rough size of the freeship exe file. 45-258 kb is the size range of various 32-bit and 64-bit hydrodynamics plug-ins Victor Timoshenko and Holtrop/Feng/ others wrote to estimate resistance, turning, acceleration, braking, hydrostatics, and powering. It's not a CAD program, but those little bits of compact code give me things a general and even surface modeling/solid modeling CAD program normally can't. But, VOLUME is one of those things a respectable CAD program like VCP and Shark should do.

Volume can and should be measurable whether the user selects a solid, or "lassos" 80% of a box, or almost-closed geometric container. We can fill up glasses and bathtubs and know the rough volume by measuring the shapes, deducting lost volume by use of appropriate formulas or coefficients. There is no requirement to seal the tub or put a lid on a mug or glass. CAD software could do that digitally, and could propose a virtual "containment" that hugs the shape of the object to be measured. The user could then work and keep track of volumetric considerations before having to find out long into the process that a minor shape change will cascade into a massive redraw (let's say stress or structure are not sufficiently estimated beforehand.)

This would be useful for those who need to size fuel tanks, balancing containers, spill-over troughs, and more, that are not simple cube or rectangular shapes.

No, I'm not saying to make VCP/Shark behave like hydrostatics programs. But, if anyone is drawing beakers, pipelines, swimming pools, etc, it would take a LOT of file size to solidify a 40'x-90', irregularly-shaped swimming pool. It might take a lot of unnecessary CPU cycles to measure ducting flow volume.

So, what is it that endows some 4MB of files (one core and 1 plug-in file) of mostly open source code to give me in 4 seconds the volume of a body without a sealing, top deck, (the body of a vessel, a mesh, not a solid) but VCP and Shark won't do until a surface is stitched or solidified and sealed to some ACIS-capable tolerance?

Further, in that model, I need only click on "Design Hydrostatics", and I get a nice, tidy columnar (selectable/copyable/pastable) list of layers weight (I set the thickness and density), CGs (XYZ), weight summaries (at the end of the list)...

VCP and Shark nicely know coordinates. I firmly, FIRMLY believe in drawing according to the spatial positioning of the master environment an object will go into. Unfortunately for some, file size and expediency preclude their doing that in AutoCAD. But, in VCP/Shark, I like they way the coordinates work for me, not make me fight to understand them. So, if VCP and Shark allowed us to draw "zonal boxes" at locations in my model, I could a little easier keep track of things. But, nicely, VCP and Shark have a great output format for weights and moments in the mass tool as well as in the BOM.

Maybe another user who designs vessels and aircraft might be able to round out my thinking. Basically, what I'm getting at is that maybe VCP/Shark need a sort of "global" and "ad hoc-placed" "boundary" system to complement the coordinate system. Maybe this could tie in with volumes estimations. It might help some of the geekier designers do interesting things if they have more calculations and limits tools in VCP/Shark.

Sorry this was a "long" post.

Thanks, Zumer.

IIRC, I tried that some time ago in, maybe 2 years ago. The issue I was having is that my models import with a beautiful mesh that cannot be used for trimming the solid deck or the solid that could be the compartment. So, I have to convert that beautiful mesh to a lumpy, bazillion-facets/vertices surface or other intermediate types. After stitching them to regain the quasi-look-alike surface, the facets in the shape thwart my attempts to get a good extrusion across to terminate at or beyond it. So, I have to compromise, and build a surface from the curves (DXF polylines) that I imported, but converted to bsplines (so that surfaces properly form from end to end, not terminate short of the line's length)

I appreciate that it is GP CAD. But, the software needn't know I'm modeling a ship. ACIS needs to figure out how to allow the user to trim off things *right at the edge* of a plane. In other words, when I had a surface or solid (the sideshell in this case) and wanted to sweep a surface (deck) to later be solidified, I could not terminate a sweep at the same x coordinate.


I have to come up with bizarre, time-consuming workarounds because I put too much effort or value into keeping the bsplines-influencing surfaces faithfully following my Freeship model.

But, again, thanks for your refresher on extruding surfaces or using a solid and Booleaning or splitting the solid. I was so self-stressing that I completely, utterly forgot to revisit the method you mentions. I did it in PolyCAD, and stupidly forgot to try to reapply it to VCP, even as recently as December. (It's possible I tried it and sputtered out with ACIS, as all December long I was hitting one ACIS limitation after another, forcing me to soul-search/re-rationalize how I'm exploiting entities in the models I'm making. I've probably been over-thinking things.)

Thanks, Zumer! I'll revisit your method. I think it'll work, as *long* as ACIS has no issue terminating right at the edge, otherwise I'll have to do weird trimming.