PROGRD Version 0.6

Date: October, 1999.

PROGRD is used to project a user-defined set of points onto a collection of panel networks (defined by PLOT3D multiple surface grids). Projection is performed onto the bilinear surface defined by the collection of panel networks. The entire set of panel networks may be divided into several families where the user can specify which points are projected on to which family. PROGRD can also be used to project a set of points onto a surface triangulation.

This is almost a total re-write of the old PROGRD to include much more general features (see list below). Currently, this version of PROGRD has all the capabilities of the old PROGRD and it should be much more convenient to use. For example, a user can define the entire surface domain (split into families if necessary) as the reference surface, and the entire surface domain (according to families if necessary) as the active points. If iblanks are supplied in the input grid file after a domain connectivity run using PEGSUS or DCF3D, all the outer boundary points and hole boundary points will be automatically projected under the current MODE 2.

Current features:

• Reference surface, active grid points can be any J, K or L subsets from a single or multiple grid file.
• Reference surface can be split into families.
• A family can be one of 3 types:

    TYPE 2 : bilinear surface - can have multiple members,
    TYPE 1 : curve - can have just one member,
    TYPE 0 : point - can have just one member.

• Active subsets are projected according to families.
• Projection of specified active points.
• Projection of points with negative iblanks or 101 iblanks in specified regions (both outer boundary and hole boundary points).
• Auto single or double fringe projections of outer/hole boundary points (must supply at least 2 layers of iblanks if double fringe).
• N-shift (general form of L-shift used in earlier PROGRD).
• Projection directions (1/2/3/4).
• Projection options if active point is outside reference family.
• Surface normals test to obtain initial guess for first point in each contiguous group of points in each active subset.
• Auto determination of topologies of active subsets.
• Auto maintainance of topologies after projection.
• Auto surface/curve/point projection based on type.
• Dynamic memory allocation for grid and tmp arrays.
• Error reporting to error log file.
• Store 2 pointers for neighboring pts at boundaries.
• PLOT3D command files to view reference surfaces and families, original and projected active points, distance moved by projected points, active points that moved by zero distance, surface normals of projected points.
• Jacobians checks as computed by OVERFLOW for shifted active volume grids.

To be developed:

• Cell area check for bad projections?

Input

   NRFAM = Number of reference surface families.
   NRSUB = Number of reference subsets.
   NSUB  = Number of active subsets.

   IFAM  = Family number.

   IMODE = 1    Project specified active points according to families (old MODE 1).
         = 2    Project points with negative domain connectivity
                iblanks and orphan iblanks (101) in specified regions
                according to families (old MODE 3). This includes
                both outer boundary and hole boundary points for
                single or double fringe.
         = 3    Make active subset points coincident with reference
                subset points (old MODE 4).
         = 11   Compute and output u,v indices of specified active
                points in terms of reference surface indices (old MODE 5).
         = 12   Project according to info computed in MODE = 11 onto
                a possibly different reference surface (old MODE 6).

   IPRO  = ab   where ab is a 2-digit integer with
                a = projection direction (1=x, 2=y, 3=z, 4=normal)
                b = projection option if active point is outside reference family
                  = 0    Do not move point.
                  = 1    Project point to closest cell on reference family.
                  = 2    Project point to extrapolated surface of reference family.

   NSHIFT is used if active subset is a surface, curve or point.
   NSHIFT = 0   move only points defined in active subsets
          = ab  where ab is a 2-digit integer with
                a = 1,2,3 indicate shift directions J,K,L respectively
                b = 1    move all points in J/K/L direction by same inc.
                         as surface point.
                  = 2    move near half of points in J/K/L direction by
                         same inc. as surface point.
                  = 3    hold opposite boundary fixed in J/K/L direction
                         and redistribute intermediate points based on
                         arclength.
                         e.g. NSHIFT=31 means shift all points in L-direction
                         by same increment as active surface.

Special note for triangulated reference surfaces

• Reference surface filename should have extension .tri or .fst for CART3D or FAST formats respectively. File could be formatted or unformatted.
• NRFAM and the entire input block under NRSUB should be omitted.

Output PLOT3D command files

   minmax.com - minmax
   refs.com   - reference subsets all colored gray.
   reff.com   - reference subsets colored by family.
   orip.com   - original active grid points colored by subset.
   prop.com   - projected active grid points colored by subset.
   dmov.com   - projected active grid points colored by distance moved.
   prom.com   - refs.com followed by dmov.com.
   snap.com   - refs.com followed by surface normals of active points.

Parameters in main program

   MSUB  = max no. of subsets for reference or active grids.
   MGRID = max no. of grids for reference or active grids.

   Static memory required = 46*MSUB + 8*MGRID

Current Restrictions:

• Mode 3: The old version of PROGRD would check the reference grid J and K indices against the active grid J and K indices, and, if necessary, flip them in an attempt to do the correct projection; that capability is not in the new version.  As it is, the code will check to make sure that the reference and active grid subsets have the same number of points and, if so, do the 1-1 projection starting from the 1st point in each subset.  If the direction in the reference grid is incorrect, the user will need to use GRIDED to flip and/or reverse indices.  If there is more than one reference grid in the family, PROGRD will search for that subset with the same number of grid points as the active grid; if more than one grid satisfies that condition, it will choose the 1st listed reference grid for which the J and K indices match J and K of the active grid.
• Modes 11 and 12: The parametric projection is currently restricted to projections on a reference surface (no projection on a curve is available at this time).  Since mode 11 uses the same routines as mode 1, the projection can be onto a family of multiple reference surfaces.  However, to keep track of which reference surface the parametric variables are coming from and which active surface the parametric variables are associated with, the reference and active grid subsets must have the same ordering in modes 11 and 12.  Moreover, the ranges of indices must be identical.  However, the grid numbers from which the subsets are extracted can differ.  Hence, one can, for instance, read in an initial multiblock grid.in file as both the active and reference grid to obtain the parametric data from mode 11, than use mode 12 with just single block grids read in as the reference and active grids.  When mode 11 is used, no projections other than mode11 will be performed, an output grid will not be written, and, while all of the reference grid subsets will be listed in the plotting command files, the only active grids listed will be those which use mode 11.
• For best results, active entities should not be too far from a reference surface composed of triangles.

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Last Modified: Monday, 07-Jan-2008 11:57:35 PST