How to create 3D object from scratch

HOOPS Visualize
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HOOPS Visualize Shell geometry accept not only triangle faces but also any planner faces specified by a PointArray. The following example shows you how to create H beam with a hole, that may be useful for AEC application.

Step 1 : Create a PointArray of H beam profile, and a Hole

	float H = 100;
	float B = 50;
	float t1 = 5;
	float t2 = 7;
	float L = 500;

	// Create H Profile with 12 Points x 2, 2 Holes with 32 Points x 2
	PointArray pts(88);
	pts[0] = Point(t1 / 2, H / 2 - t2, 0);
	pts[1] = Point(B / 2, H / 2 - t2, 0);
	pts[2] = Point(B / 2, H / 2, 0);

	for (int i = 0; i < 3; i++)
	{
		pts[3 + i] = pts[2 - i]; pts[3 + i].x = -pts[2 - i].x;
		pts[6 + i] = -pts[i];
		pts[9 + i] = pts[2 - i]; pts[9 + i].y = -pts[2 - i].y;
	}

	for (int i = 0; i < 12; i++)
	{
		pts[i+12] = pts[i];	pts[i+12].z = L;
	}

	// Hole
	Point Center = Point(t1/2, 0, 20);
	Vector UDir = Vector(0, 1, 0);
	Vector VDir = Vector(0, 0, 1);
	float dRadius = 5;
	double dCoordU;
	double dCoordV;
	double M_PI = 3.141592;

	for (int i = 0; i < 32; i++)
	{
		dCoordU = dRadius * cos(M_PI / 2 * i / 8);
		dCoordV = dRadius * sin(M_PI / 2 * i / 8);
		pts[55-i] = Center + dCoordU * UDir + dCoordV * VDir;
		pts[56+i] = pts[55-i]; pts[56+i].x = -pts[55-i].x;
	}

Step 2 : Create a Facelist of H beam profile, a Hole, and side faces

	// Create Face List : H Profile with 13 x 2, Holes with 33 x 2, Side Faces with 5 x 12
	IntArray flist(152);
	flist[0] = 12; 	flist[13] = 12;
	for (int i = 0; i < 12; i++)
	{
		flist[i + 1] = i; flist[i + 14] = 23-i;
	}

	// Face1 with a Hole
	flist[26] = 4;
	flist[27] = 0;
	flist[28] = 11;
	flist[29] = 23;
	flist[30] = 12;

	// Hole1
	flist[31] = -32;
	int j = 24;
	for (int i = 32; i < 64; i++)
	{
		flist[i] = j++;
	}

	// Face2 with a Hole
	flist[64] = 4;
	flist[65] = 6;
	flist[66] = 5;
	flist[67] = 17;
	flist[68] = 18;
	flist[69] = -32;

	// Hole2
	j = 56;
	for (int i = 70; i < 102; i++)
	{
		flist[i] = j++;
	}

	// Side Faces without a Hole
	j = 102;
	for (int k = 0; k < 11; k++)
	{
		if (k == 5) continue;
		flist[j++] = 4;
		flist[j++] = k + 1;
		flist[j++] = k;
		flist[j++] = k + 12;
		flist[j++] = k + 13;
	}

Step 3 : Insert Shell. You can test the code in Sandbox

	SegmentKey indicated_key = GetDocument()->GetModel().GetSegmentKey();
	indicated_key.GetVisibilityControl().SetEdges(true);
	indicated_key.InsertShell(pts, flist);
	GetCanvas().GetFrontView().FitWorld();
	GetCanvas().Update();
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