Compute a flow surface

This module constructs flow surfaces with several lines. From a starting point, an initial line is computed. A flow line starts from several points on this initial line.

• First you can adjust the surface parameters. Press the ``parameters'' button in the ``SURFACE'' frame, a window appears (see figure 1.45) :
  $\bullet$ ``m'' is the maximum number of points on a flow line.
  $\bullet$ ``k'' is the number of steps between 2 mesh points on the flow line.
  $\bullet$ ``n'' : is the length of the initial line.
  $\bullet$ ``e'' the step'' between 2 points on a initial line.

  You can ``Set'' new values, ``save'' them in a file (the default one is ``surf_param.flow''), ``reset'' to the initial values or ``restore'' the saved parameters.

  Figure 1.45: Flow surface parameters.

  

• Push the ``create'' button in the ``SURFACE'' frame to compute a flow surface :
  $\bullet$ A ``regular tiling'' takes a point in each adjacent flow line.
  $\bullet$ A ``minimal tiling'' tries to minimize the tiles which form the surface.
• Some messages appear if no point has been chosen or if it is out of the mesh, or else if the number of points on the flow surface is under the chosen parameters.
• You can ``save'' a flow surface, then set the toggle ``surfaces'' on to redraw the saved flow surfaces in the drawing area.
• You can use the ``draw'' button in the ``SURFACE'' frame to select which saved surfaces will be drawn.