# Forum

### Author Topic: Calculation of 3D-Area  (Read 760 times)

#### SebastianStumpf

• Newbie
• Posts: 5
##### Calculation of 3D-Area
« on: October 04, 2021, 09:25:10 PM »
When drawing a polygon, the 2D-Area can be measured, but not the 3D-Area. On the other hand, in the Cloud, that feature was already implemented and is just called "Area" (see screenshot).

This feature would be very useful for calculating for example roof-Area or even building facades-area, which today, because of being 2D-Area it reports around 0 m2 (projection of points to ground).

#### Ilya Shevelev

• Newbie
• Posts: 23
• Agisoft Cloud Technical Support
##### Re: Calculation of 3D-Area
« Reply #1 on: October 05, 2021, 07:34:37 PM »
Dear Sebastian,

The *Area* property that is automatically calculated when drawing the polygon is not a 3D area of the surface under the polygon, but an area of the polygon, projected onto the plane best fitting the polygon's vertices. This method  is good enough, when it is needed to measure an area of the vertical or oblique surface, like facade or roof, but it is not the right method if it is needed to measure the surface area of a complex object.

The detailed description of how all the measurements in the cloud are performed may be found in our knowledgebase: https://agisoft.freshdesk.com/support/solutions/articles/31000160891-how-to-measure-and-annotate-your-projects

Can you please specify if the current method provides your needs, or you need to measure the 3D area of the surface under the polygon?

Best regards,
Ilya Shevelev
Best regards,
Ilya Shevelev
Agisoft LLC

#### SebastianStumpf

• Newbie
• Posts: 5
##### Re: Calculation of 3D-Area
« Reply #2 on: October 05, 2021, 07:47:09 PM »
Dear Ilya,