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SketchUp How do I create a canal

I would like to create a canal for small boats using Sketchup 2021.
I've searched the internet but can't find anything right now.
The water is 4 meters below ground level (so -4 meters).
But how do I do this?
Thanks in advance
Hi Peter:

Would you be willing to share some Geographic coordinates for this project so we can see what the existing terrain involves ? :scratchch

Assuming output for FSX/P3D, position a canal 3D model bottom base plane at Sketchup's Origin of Axes; this would allow it to be placed via BGLComp with its bottom plane on the ground of the FS2Kx underlying terrain mesh at (-) 4 Meters AGL.

If you remove the canal 3D model bottom Face, terrain Hydro polys and a Water Class 'color' texture may be added via custom photo-real or land class polygon methods, so that actual FS water shows on the underlying terrain mesh surface.

If one makes a FS2Kx terrain mesh quad grid "canal", it will alias / 'morph' via LOD-switching as a function of user A/C camera distance from the 3D object, regardless of FSX/P3D *.CFG file mesh resolution and TMVL settings used, (even if the 3D object is precisely aligned on FS' N-S, E-W world grid). :alert:

Thus, one must "dig a ditch" into underlying terrain mesh via a CVX vector "sloped flatten"; one's canal 3D model is placed (via BGLComp) in that "ditch".

One may use 3D model terrain 'skirts' to cover up "ditch" edges of nearby underlying terrain quads.

NOTE: A textured terrain skirt may not change with seasons unless the MDL is made as a (non-flat) G-Poly or SimObject with conditional texture display.

After making your 3D model of the canal and its sloped sides, make a copy of it scaled slightly larger without the terrain skirts over the edges.

In Sketchup, manually Geo-locate that larger scaled 3D model of the canal and its sloped sides at its intended position / N-S-E-W orientation in FS2Kx.

Export that larger scaled 3D model of the canal and its sloped sides from Sketchup as a Google Earth *.KMZ file.

Import that larger, scaled and copied 3D model *.KMZ file into Arno's MCX.

In MCX, export that copied larger, scaled and 3D model as a "FSX Sloped Flatten" CVX vector BGL; then test it in FSX / P3D.

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Hi Gary,
Wow, that's a serious explanation.
I don't think I'll go any further with that because I'm not the youngest anymore and it's getting more difficult to learn things.
If it really was a remarkable point, then I would say, but it is not that important now.
I had this in mind as decorative, but thanks anyway for your help and time put into it.
Hi Peter:

If one had A.I. boats in the canal alongside EBFN that might make the Belgian Military develop a more relaxed attitude. ;)


The terrain is rather flat locally, and a canal ditch sloped flatten with nearby roads could be made fairly easily in SBuilderX. :idea:

One may load a SASPlanet source photo-real BMP in SBuilderX as a background map in EPSG:3857 via Add Map > From Disk.



  • EBFN_Canal.jpg
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Actually, you're right Gary.
I'm going to start anyway.
Thanks again for your support,
So far so good Garry,
I made a photoreal of the canal with SBuilderX.
The photoreal of the canal has been placed in P3Dv4.
How does it work if I want to create the canal ditch, street and walkway in SBuilderX?
I've never done anything like this with SBuilderX.
So I am now going to study Luis Sa's Tutorial 'Terrain Design for FSX'.
Canal Veurne - Nieuwpoort.jpg
Hi Peter:

IIUC, you refer to Luis Feliz-Tirado's tutorial on Terrain Design for FSX?

Luis Sa', SBuilder / SBuilderX author, did make numerous helpful mini-tutorials in the forums ...as well as SBuilder's Help files.

Generally speaking, custom photo-real textures draped onto terrain or 3D models (including G-Polys) can have high resolutions.

IIRC, default and most custom 3rd party Land Class texture display may be limited to ~ 1 Meter per pixel resolution at run time

In FSX, if using 3D models / G-Polys for higher resolution textured objects, they must be made using G-Poly VTP Layer numbers in order to minimize flickering and Z-Buffer fighting artifacts (especially in Top-Down View) between the G-Poly and the underlying Ground surface.

P3D implemented Material Functionality to use the equivalent of old SCASM / ASM VTP Layer numbering methods for G-Polys:


IIRC, Arno's MCX G-Poly Wizard can apply this when P3D output is toggled for a G-Poly.

To maximize alignment of canal hydro / water class texture polys, as well as canal ditch, street and walkway 3D objects ...with satellite imagery, one can make CVX vector Polygons of the outlines for those structures in SBuilderX.

Then one can compile CVX vector BGLs and extract them to ESRI *.SHP files with CvxExtractor.

The output *.SHP files must be re-projected to EPSG:3857 in a GIS app, then they can be imported into Sketchup via a special plugin Ruby script.

Once imported to Sketchup, the (former) CVX vectors can be used to make 3D models of the canal street and walkway with high resolution textures.

Those objects can then be exported as *.KMZ files and imported to MCX.

MCX can then use those objects to make G-Polys with high resolution textures.

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