How to calculate a voulme

The Costs depending on volumes are calculated by your program, though it was really not easy to find this way. (The table also shows optional costs per piece, what is nothing else than your cost and ext.cost).

But:

The volume your program is calculating can be wrong.

Here the correct volume would be 8m³ (0.5 * 4m * 4m * 1m), an that's the value, Sketchup lists for this komponent, but you use lenx*leny*lenz, what means 4m*4m*1m=16m³. Thats not fine, really.

It gets even worse, if you set a text-mark to your component (e.g. the area of the upside) as this makes lenz higher...

After all, Sketchup reduces every element to a polyhedron, even a circle or a globe. So there should exist one general mathematical routine to calculate the exact volume. Also for areas this should be possible.

I know, all this is not easy to programm, especially as you have to respect some limits Sketchup and ruby may make, but it would be very fine, if you solved it.

We as architects calculate costs regularly on areas and volumes, and we like to use Sketchup in the beginning of designing a object. We would like to use your plug-in too, but we can not ONLY build rectangles. But if you know the solution you will have very much success with this plug-in.

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Permalink Reply by Render Plus on February 4, 2011 at 7:50am

SketchUp 8 has a new volume calculation for solids.

I have changed %v% to use it, and It gives much better results.

I will post a new version later today.

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Permalink Reply by Gerald Neuber on February 7, 2011 at 12:14am

Is your new version to be downloaded yet?

I did a new download (after having deleted the older version) but the problem was the same again.

Thanks

Gerald Neuber

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Permalink Reply by Render Plus on February 7, 2011 at 9:16am

sorry - I won't be able to make it until tomorrow.

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Permalink Reply by Render Plus on February 9, 2011 at 5:53am

I didn;t get the new version out yesterday. I will try again today.

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Permalink Reply by Render Plus on February 9, 2011 at 10:08pm

See: New Version KB09

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Permalink Reply by Paolo Zago on February 11, 2011 at 12:08pm

I have a problem with the report: the volume don't appears in metric units. Why?

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Permalink Reply by Render Plus on February 11, 2011 at 4:28pm

A couple of answers:

1. We really don't know what metric volume would want. In the US, cubic inches, cbic feet and cubic yards are are meaningful for different applications. (Would you want to know the volume of a 3cm x 4cm x 5cm object in cubic meters, or is there a preferred unit.)

2. The SketchUp database is always in inches, so we just multiply the dimensions in inches by each other to get a value. You can add a division to your calculation, e.g. the /39.37007874 in my example above).

There are a couple of potential solutions:

A. We could add a setup option for desired area units.

B. We could offer several %v% options, such as %v-m" for cubic meters, etc.

I am leaning towards the second option, B, because it is easier for me.

Also there may be reports where you want to report a volume in Cubic Meters for one attribute, but a volume in cubic centimeters for another attribute int he same report.

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Permalink Reply by Render Plus on February 12, 2011 at 10:50pm

I added a couple new substitutions for volume: %v-m% will calculate the volume in cubic meters, %v-cm% will calculate the volume in cubic centimeters, and %v-f% will calculate the volume in cubic feet.

Let me know if you need any more standard units.

%v-m% is the same as %v%/61023.744095

I will put out a new version next week.

We use the SketchUp calculation VOLUME/(1.0m * 1.0m * 1.0m) to convert from cubic inches to cubic meters.

See: Substitutions

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Permalink Reply by Render Plus on February 14, 2011 at 9:37am

I tested your new version and was very happy about it.

The volumes were calculated correctly, even pyramides and cylinders.

The only question left for me is, if it would be possible to calculate areas (m², square-foot).

That function would complete your program perfectly. Lengths may be able to be calculated by %lenx%, I believe, but did not try yet.

I recognised, that Sketchup does not calculate areas by itself, for 2D-components in its element-information.

But it should be possible, to copy one 2D-component, to make it to a volume by using Push/Pull with e.g. 1 foot or 1 m an using the element-information-volume divided by 1m / 1 foot for calculating th cost of the origin 2D-Elements; after having created the report, you easily delete the 3D-component.

You surely may know Sketchup better than I, and I see you are doing well.

If you want a rectangular area, you can use %w-m% * %d-m%. This will have the same problem of including items outside the desired area, and of not working with strange shapes.

We have left out %a% for area - because there are three possible orientations to use for area. So you should multiply %w% x %h% , etc., based on which surface you want.

Your idea of creating a solid to get areas is intresting. However many users want to calculate the "area" of a 3-D object. e.g. the surface area of a wall or the visible area of a "sign".

If we start generating geometry from existing geometry we might run into all kinds of problems.

You might try making your flat components thick - say 1mm thick - as you describe and dividing the volume by the thickness to get the area. e.g. %v-d%/%h-m% - assuming you made th thickness in the Z direction.