Examples > Kinematic > Spiral surfaces

Spiral surfaces.

Let's create a spiral surface with an arc-clip.

This code creates an arc:

SG_ARC ArcGeo;

SG_POINT ArP1 = {-1.0, -3.0, 0.0};

SG_POINT ArP2 = {-1.0, -2.0, 0.0};

SG_POINT ArP3 = {0.0, -3.5, 0.0};

ArcGeo.FromTreePoints(ArP1,ArP2,ArP3,false);

sgC2DObject* ar = sgCreateArc(ArcGeo);

sgGetScene()->AttachObject(ar);

ar->SetAttribute(SG_OA_COLOR,12);

ar->SetAttribute(SG_OA_LINE_THICKNESS, 2);

The axis of the spiral will lie on the (2, -3, 0) and (2, 3, 0) points. As the spiral clip isn't a closed object there will be no holes. Length of a spiral step will be 4, the spiral length - 10, and the number of meridians on the one spiral step circle will be 15:

SG_POINT axeP1 = {2.0, -3.0, 0.0};

SG_POINT axeP2 = {2.0, 3.0, 0.0};

sgC3DObject* spirO = (sgC3DObject*)sgKinematic::Spiral((const sgC2DObject&)(*ar),NULL,0,

axeP1,axeP2,4,10,15,false);

sgGetScene()->AttachObject(spirO);

spirO->SetAttribute(SG_OA_COLOR,85);

Then we'll move the obtained surface:

SG_VECTOR transV1 = {0,-11.5,0};

spirO->InitTempMatrix()->Translate(transV1);

spirO->ApplyTempMatrix();

spirO->DestroyTempMatrix();