62 lines
1.8 KiB
Plaintext
62 lines
1.8 KiB
Plaintext
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/** \page tutorial_02 Using iterators and circulators
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This examples shows:
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- How to use iterators,
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- How to use circulators.
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This example is the first version of the simple mesh smoother. Here we
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will introduce \em iterators and \em circulators. These two concepts
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provide functionality to linearly enumerate e.g. all vertices of a
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mesh, and to circulate around a vertex, i.e. to enumerate all its
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one-ring neighbors. For a more detailed description, see \ref
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mesh_iterators.
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First we have to define the mesh type we want to use. This time we use
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a triangle mesh instead of a polygonal mesh:
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\dontinclude 02-iterators/smooth.cc
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\skipline TriMesh_ArrayKernel
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\skipline MyMesh
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<br>We read the mesh to be smoothed from a file:
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\skipline read_mesh
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<br>One smoothing iteration is done in two steps:
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<ol>
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<li>For each vertex: calculate the barycenter of its one-ring neighbors.</li>
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<li>For each vertex: move the vertex to the computed barycenter.</li>
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</ol>
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This can easily be implemented using vertex iterators. The mesh
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provides begin and end iterators by <tt>vertices_begin()</tt> and
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<tt>vertices_end()</tt>.
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\skipline VertexIter
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\skipline v_it!=v_end
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<br>For calculating the barycenter, we have to iterate through the
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one-ring neighborhood of the current vertex. This functionality
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is provided by the <tt>VertexVertexIter</tt>:
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\dontinclude 02-iterators/smooth.cc
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\skipline VertexVertexIter
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\skipline vv_it=
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<br>Now we can calculate the barycenters for each vertex and store them in
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the array <tt>cogs</tt>:
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\dontinclude 02-iterators/smooth.cc
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\skipline std::vector
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\skipline v_it=
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\until cogs.push_back
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\until }
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<br>After we have calculated the barycenters all that is left to do is to
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move the vertices to the corresponding barycenters. The complete source
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code is listed below.
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\include 02-iterators/smooth.cc
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**/
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