In general you can replace a region by a single point with all the mass concentrated at that point.
So if you had a collection of triangles and you wanted the overall center of mass you would do:
1. Find the center of mass of each triangle.
2. Multiply these coordinates by the mass ( area ) of the triangle.
3. Add these together.
4. Divide by the total mass.
The hard part is calculating the areas. You would use vector cross product for this.
So if you had a collection of triangles and you wanted the overall center of mass you would do:
1. Find the center of mass of each triangle.
2. Multiply these coordinates by the mass ( area ) of the triangle.
3. Add these together.
4. Divide by the total mass.
The hard part is calculating the areas. You would use vector cross product for this.