Is it possible to get the area of a mesh?

general discussion
#1

Is it possible to get the area of a mesh, for instance an imaginary containing rectangle?

Thanks.

#2

Not sure if you’re talking about computing volume or a bounding box/volume. Or do you want a 2D rectangle that contains the mesh?

#3

Hi,

Is this for 2D or 3D?

For 3D something like this would give you a bounding box for a list of points, calculating the area (well, volume in 3D) is then just a matter of width * height * depth.

	// --------------------------------------------
	void calculateAABoundingBox( vector<ofVec3f>& _points )
	{
		ofVec3f min(  99999999999999999,  99999999999999999,  99999999999999999 );
		ofVec3f max( -99999999999999999, -99999999999999999, -99999999999999999 );

		for( unsigned int i = 0; i < _points.size(); i++ )
		{
			ofVec3f p = _points.at(i);

			min.x = MIN( min.x, p.x );
			min.y = MIN( min.y, p.y );
			min.z = MIN( min.z, p.z );

			max.x = MAX( max.x, p.x );
			max.y = MAX( max.y, p.y );
			max.z = MAX( max.z, p.z );
		}

		setSize( max - min );
		setPosition( min.getInterpolated( max, 0.5f ) );
	}
#4

@hahakid Wonderful - thanks!

#5

@hahakid not sure if I understand what setSize(min-max) is doing?

#6

ignore me - understand it now!

#7

No worries, should have posted the whole thing, here we go:

And one for Oriented Bounding Boxes, though it won’t calculate an oriented bounding box for you, just for checking if points are inside.

1 Like
#8

Cheers - got your original snippet plugged in and working great. Thanks again.