private void MakeObjects(out MeshGeometry3D cameraMesh,
out MeshGeometry3D boxMesh, out MeshGeometry3D edgeMesh,
out Point3D cameraCenter)
{
// Make a "camera."
cameraMesh = new MeshGeometry3D();
cameraMesh.AddBox(new Point3D(-0.6, -0.5, -0.2),
D3.XVector(1.2), D3.YVector(1), D3.ZVector(0.4));
Point3D[] points = G3.MakePolygonPoints(20, new Point3D(0, 0, -0.7),
D3.XVector(0.3), D3.YVector(0.3));
cameraMesh.AddCylinder(points, D3.ZVector(0.7), true);
points = G3.MakePolygonPoints(20, new Point3D(0, 0, -0.8),
D3.XVector(0.4), D3.YVector(0.4));
cameraMesh.AddCylinder(points, D3.ZVector(0.2), true);
cameraMesh.AddBox(new Point3D(0.3, 0.5, -0.1),
D3.XVector(0.2), D3.YVector(0.2), D3.ZVector(0.2));
MainGroup.Children.Add(cameraMesh.MakeModel(Brushes.LightBlue));
// Transform the camera and vector.
Transform3DGroup trans = new Transform3DGroup();
RotateTransform3D r1 = D3.Rotate(D3.XVector(), D3.Origin, -45);
trans.Children.Add(r1);
RotateTransform3D r2 = D3.Rotate(D3.YVector(), D3.Origin, -45);
trans.Children.Add(r2);
// See where we need to translate to make the camera point at the origin.
Point3D lookAtPoint = new Point3D(0, 0, -3.5);
lookAtPoint = trans.Transform(lookAtPoint);
TranslateTransform3D t1 = new TranslateTransform3D(
-lookAtPoint.X, -lookAtPoint.Y, -lookAtPoint.Z);
trans.Children.Add(t1);
cameraMesh.ApplyTransformation(trans);
cameraCenter = trans.Transform(D3.Origin);
// Make a target box.
boxMesh = new MeshGeometry3D();
boxMesh.AddBox(new Point3D(-0.75, -0.75, -0.75),
D3.XVector(1.5), D3.YVector(1.5), D3.ZVector(1.5));
MainGroup.Children.Add(boxMesh.MakeModel(Brushes.LightGreen));
// Make the box's edges.
edgeMesh = new MeshGeometry3D();
HashSet <Edge> edges = new HashSet <Edge>();
edgeMesh.AddBox(new Point3D(-0.75, -0.75, -0.75),
D3.XVector(1.5), D3.YVector(1.5), D3.ZVector(1.5), edges: edges);
MainGroup.Children.Add(edgeMesh.MakeModel(Brushes.Black));
}
// Define the model.
private void DefineModel()
{
// Axes.
MeshExtensions.AddAxes(MainGroup);
// Make the objects.
MeshGeometry3D cameraMesh, boxMesh, edgeMesh;
Point3D cameraCenter;
MakeObjects(out cameraMesh, out boxMesh, out edgeMesh, out cameraCenter);
// Get the view transform.
Matrix3D viewMat = Cameras.GetViewMatrix(
new Point3D(cameraCenter.X, cameraCenter.Y, cameraCenter.Z),
new Vector3D(-cameraCenter.X, -cameraCenter.Y, -cameraCenter.Z),
D3.YVector());
// Apply the view transform.
cameraMesh.ApplyTransformation(viewMat);
boxMesh.ApplyTransformation(viewMat);
edgeMesh.ApplyTransformation(viewMat);
// Get the projection transformation.
Matrix3D projMat = Cameras.GetPerspectiveProjectionMatrix(
60, 0.125, double.PositiveInfinity,
mainViewport.ActualWidth / mainViewport.ActualHeight);
boxMesh.ApplyTransformation(projMat);
edgeMesh.ApplyTransformation(projMat);
// Rotate the camera so it makes sense.
RotateTransform3D rot = D3.Rotate(D3.YVector(), D3.Origin, 180);
cameraMesh.ApplyTransformation(rot);
// Move the objects a bit so they're not so close to the camera.
TranslateTransform3D trans = new TranslateTransform3D(0, 0, 1f);
boxMesh.ApplyTransformation(trans);
edgeMesh.ApplyTransformation(trans);
}