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erschrei July 28, 2009 12:46

Prism Layer "Zone Specific Growth" Option not working!
I need to grow different size prisms on different parts on my surface mesh. I have been trying to use the Zone Specific Growth box for a couple days now, but it seems to try to grow all the prisms to the initial height and ratio that was last clicked on instead!

I have grouped a zone "Prism" that includes all my surfaces, which I highlight before I click on "Create". I set all of them separately using the 'Apply" in the Zone Specific Growth, and no dice.

It seems to try and work with the Auto Mesh, but it tries to triangulate parts of my surface mesh that should not be triangulated and so it errors out, and hence I have been trying to grow the prisms solo and then add pyramids and tetrahedrals.

Any suggestions or wisdom on the matter would be greatly appreciated!


PSYMN July 29, 2009 09:57

I thought those Zone specific growth ratios applied to the local rate of TETRA expansion. TGrid Prism controls are all global...

Any one else try this?

PSYMN July 29, 2009 11:29

This was in the TGrid Manual. It should help.;)

10.3.1 Growing Prisms Simultaneously from Multiple Zones
You can select multiple face zones for simultaneously growing prism layers. If the face zones are connected, the prisms grown will also be connected. A single zone of prism cells and a single zone of cap faces will be created for each set of simultaneously grown layers. To retain the individual prism cell zones and cap face zones, enable Grow Individually in the Prisms Growth Options panel (opened by clicking the Growth Options... button).
TGrid allows you to grow prisms from multiple zones with the same or different growth parameters.
  • To use the same growth parameters for all zones, follow the steps in Section 10.2. In this case, the same number of layers are grown from all zones, and all other parameters (growth method, offset method, direction method, etc.) will remain the same.
  • To use different growth parameters for different zones, apply different growth methods, offset methods, first height, and other growth parameters (as required for the growth method selected) individually for each zone and click the Apply button in the Zone Specific Growth group box in the Prisms panel.
If you specify different growth parameters for different zones, all other parameters (direction method, offset method, etc.) can be set separately for each zone. In this case, the offset height of each node that is shared by multiple zones will be the average of the heights applied on the separate zones.
This produces a continuous transition between the zones (Figure 10.3.1). Offset smoothing (see Section 10.8) is recommended in these cases to avoid sharp height changes at such edges.

erschrei July 29, 2009 12:56

Still not cooperating
I certainly set different growth methods, offset methods, first height, and other growth parameters for each 47 of the zones, and hit Apply in the Zone Specific Growth box for all 47 of them separately.

When I hit"Create" to grow them it still only wants to grow them one size, whatever the last one I had hit "Apply" for, even though when I click on a previous zone it clearly has separate settings.


I feel like I am missing something. I will just keep trying and try not to pull my hair out. Thanks for the help!

PSYMN July 29, 2009 13:03

Tech Support
Never let software make you crazy, that is what real life is for.

If it doesn't work the way the doc says it should, contact tech support. That is what they are there for. ;^)

wadebogs August 1, 2009 12:43

what version of tgrid is it? in the latest versions you can check that the settings have applied properly by hitting "list" in the prisms panel...

It may be worth your time using a journal based on text commands to set up the growth. Contact support if it doesn't

You should be able to get tgrid 5.0.11 off your support engineer... Good luck

wadebogs August 1, 2009 12:46

also, when prism growth bombs out it's always useful to look at the quad sides to see where the problems are coming from. You can do this using the "quad" filter in the display grid panel

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