1

I am trying to find bounding box volume of an STL file using the following code. For most of the files it is working fine but for files it gives strange result, means very high X, Y and Z values. Please help me to fix it.

enter code here

    float length, breadth, height;
            float minx = 0, maxx = 0,
            miny=0, maxy=0,
            minz=0, maxz=0;


     public double signedVolumeOfTriangle(float[] p1, float[] p2, float[] p3)
    {
        double v321 = p3[0] * p2[1] * p1[2];
        double v231 = p2[0] * p3[1] * p1[2];
        double v312 = p3[0] * p1[1] * p2[2];
        double v132 = p1[0] * p3[1] * p2[2];
        double v213 = p2[0] * p1[1] * p3[2];
        double v123 = p1[0] * p2[1] * p3[2];
        double vol = (1.0 / 6.0) * (-v321 + v231 + v312 - v132 - v213 + v123);


        if (Math.Min(Math.Min(p1[0], p2[0]), p3[0]) < minx)
        {
            minx = Math.Min(Math.Min(p1[0], p2[0]), p3[0]);
        }
        else if (Math.Max(Math.Max(p1[0], p2[0]), p3[0]) > maxx)
        {
            maxx = Math.Max(Math.Max(p1[0], p2[0]), p3[0]);
        }


        if (Math.Min(Math.Min(p1[1], p2[1]), p3[1]) < miny)
        {
            miny = Math.Min(Math.Min(p1[1], p2[1]), p3[1]);
        }
        else if (Math.Max(Math.Max(p1[1], p2[1]), p3[1]) > maxy)
        {
            maxy = Math.Max(Math.Max(p1[1], p2[1]), p3[1]);
        }

        if (Math.Min(Math.Min(p1[2], p2[2]), p3[2]) < minz)
        {
            minz = Math.Min(Math.Min(p1[2], p2[2]), p3[2]);
        }
        else if (Math.Max(Math.Max(p1[2], p2[2]), p3[2]) > maxz)
        {
            maxz = Math.Max(Math.Max(p1[2], p2[2]), p3[2]);
        }

        return vol;
    }

    public float[] getBoundingBox()
    {
        length = maxx - minx;
        breadth = maxy - miny;
        height = maxz - minz;
        return new float[] { length, breadth, height };
    }

Thanks

ayha

4

1 回答 1

1

删除所有else. 计算最小值后，您仍然需要计算最大值。

此外，getBoundingBox仅返回{ length, breadth, height }aabb 的维度。它的相对位置(minx, miny, minz)丢失了。

最后，确保您的全局变量已正确初始化，例如：minx=+INFINITYand maxx=-INFINITY，与yand相同z。

于 2013-07-21T19:41:08.113 回答