An example of Gordon Surface based upon OCC

[Chris_G]

In the TIGL-file the following items don't work with the newest update
Full_Nacelle
Fuselage
Heli_Body
Spiral_Wing

Thanks for testing. I just pushed a fix.
However some models are still buggy
- test surface 4
- heli body works ( be careful, heavy computation ! ), but the surface doesn't fit the curves well

[hammax]

… OK Helibody needs a little bit computing time.
But out of the rest (770kB => 20.700kB) there could be built an airplane…

FC.18.14061

Gordon_7.PNG (82.4 KiB) Viewed 1937 times

[Chris_G]

Hey, nice!
There are many things to fix still, but that's pleasing to see this screenshot.
Thanks

[microelly2]

Wow, good results.
The gordon surface will be a big step forward.
In my test when I compare the Gordon surfaces with the source models of my test there is no big difference, what means that the gordon surface is a fast way to get a surface which we expect.
the main part of the running time is the 3D Shape, the datamodel is very sparse and until the skiun is realy needed the use of grids can speed up all.
here my tests related to the tide-bottle by freecad-heini-1.
gordon can be full parametric with sketches at the beginning.

phpBB [video]

note that the method in the video is not the method of Chris_G by my simplified version, but it demonstrates already what will be possible when the official method becomes stable.

[NormandC]

there could be built an airplane…

Nice!

Is that the C series that Bombardier basically gave away to Airbus? (And now renamed A220)

[hammax]

… maybe there could be some components of the A320. Elsewhere the name DLR is in the original files.
But that was not the intent of this gordon-surface example.
It was rather a quick and dirty access via scaling and transform/placement to show a picture.
The file is still 1.842 kB and cannot be linked here.

Gordon_8.PNG (44.39 KiB) Viewed 1856 times

[NormandC]

… maybe there could be some components of the A320. Elsewhere the name DLR is in the original files.
But that was not the intent of this gordon-surface example.

I was not really serious. This is a sensitive topic here (unfortunately Bombardier did not have the resources to market the C series by itself), revived with the recent series rename... Sorry for the off topic!

I'm very impressed with what you're able to do with these Gordon surfaces.

[Vincent B]

intersectCC failed !
intersectCC failed !
intersectCC failed !

Where's my mistake?

[freecad-heini-1]

- Make a Part.Compound out of the selected profile edges.
- Make a Part.Compound out of the selected guide edges.
- Call the Gordon surface tool on these 2 compounds (and cross fingers )[quote=hammax post_id=244008 time=1531380053

The idea of the algorithm is pretty simple.
It works on 3 intermediate surfaces :
- a surface S1 that interpolates the guides
- a surface S2 that interpolates the profiles
- a surface S3 that interpolates the intersection points of the network
The Gordon surface is : S1 + S2 - S3 ( it means that this operation is done on each corresponding control point of these surface ).
This is the easy part.
The real pain is that these surfaces must be made "compatible" before : they must have the same BSpline properties (knots, degrees, multiplicities).
This is this preliminary work that is pretty complicated to follow.

[rainman110]

Hi guys,

I am the developer of TiGL and implemented the gordon surface algorithm with my student merlin. I am really glad that you like our work

If you need any help, be it for imlementation or understanding thealgorithm, let me know.

Martin (rainman110)