Spline Patching with True Art Easy Spline

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SA9R

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True Art's Easy Spline is a huge improvement to Lighwave's limited native spline implementation. The patch preview, spline density, segment density, extrude, lathe and other tools make it a worthwhile addition to the modeling toolset. Yet, with everything working so well, I was surprised to have the following output with Easy Spline's (auto) patcher. See the image above.

Shouldn't just the outer shell be patched? Instead, there are strange twists and inner walls which distort the patch work. Of course selecting 4 splines at a time to patch works fine, but that takes a loooooooooooot of time.

Is there something that should or should not be done for this spline cage to patch correctly without selecting each section for patching by hand?
 
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In the image:
1. Just the spline cage. Each circle is composed of 2 splines, which was then extruded until making a half circle. That was then mirrored, point welded and unified.
2. A patch from 4 selected splines. Works quite well.
3. A patch from 6 selected splines. There is unwanted twisting.
4. The whole cage is (auto) patched with Easy Spline, but there is on-and-off twisting of the patches and there are always inner walls in between each patch section.
5. This a subpatched version of the patch faces in image 4. One can see that the inner walls that are formed make distortions to the outer faces at intervals.
 
In the first post images: have more splines. Two+circle is not enough for automatic detection algorithm. It does not know which side is front and which is back.

Also, points must be merged/welded. Polygons-splines must be unified (Unify Polys).

If it is essential to have less splines, there is tool which undones unneeded mesh which Freeze Spline generated ("Unfreeze")
 
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Thank you very much. Tried the same with a few more connections between the round splines by selecting two adjacent points and clicking the "Make Spline" tool for simple 2-point splines that are important for filling in a spline cage. And it worked quite well. The Easy Splines auto patcher was able to recognize the inside vs outside of the spline cage and make a good skin.

Still, when making cages and patching, merge points, unify polys, align polygons and flip are important finishing tools.

Thank you for the help.
 
You now have a chain of 2-point poly-splines..
select "horizontal" splines and MERGE them ASAP (shift-Z)..

and rerender again.

ps. Watch some native LW spline modeling video tutorial to get some experience on this topic as well. It doesn't hurt to know how to do it in native LW. Some techniques from native LW, are also applicable in EasySpline.
 
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Ok, both Easy Spline's "Smooth" tool worked as well as LW's "Merge Polys" tool. The latter one looks cleaner without all the spline end handles showing in OpenGL. The smooth spline lines certainly improved the patches.
 
"Make Spline" i.e. converting edges to 2-point splines, is just an intermediate step i.e. you have to merge them yourself as you want/need.
 
The Make Spline tool can use edges to splines? Good to know; I will have to try that when back at the computer.

I use it for connecting two points between separate splines. When extruding a spline for the first time, minimal connections are automatically made. So I select points between the original spline and the newly extruded spline and click the Make Spline tool to make simple 2-pt spline connections. Then when another extrusion is made, all of the newly made simple connecting splines are duplicated, which is great.
 
Make Box, then "Make Spline", enable EasySpline interactive previewer. You have box spline cage.

Make 3 object (in your case toroid), then "Make Spline", enable EasySpline interactive previewer. You have 3d object spline cage. Merge splines ("Unify Polys") to make it smooth.
 
It is interesting that a box spline cage and a box subpatch make very different smoothed shapes.

It is good to have the tools and an efficient workflow for checking two different smoothed object options.

They can be seen in the image below.
The outer box is the spline cage patch.
The inner box is the subpatch box.
They both have their faces subpatched and frozen in the image.

Not really the full boxes since they are both missing the front and back panels. So they are more like a loop based on a box of the same size.

 
It is no surprise. Sub-Patch does not pass through control points. Spline cage pass through the all control points.
 
Interestingly, I just realized that a closed object made of closed spline loops is toroidal because of how splines work. A box made of closed spline loops is actually impossible. It can only be made of the relatively disconnected 2pt splines, which is a good feature itself.
 
If you're going to have closed splines in the spline cage of the box, add more splines in the opposite direction, lots more.
The same is true of Sub-Patch (additional edge loops).
The corners and edges of the spline-cage/Sub-Patch box will be natively rounded without doing anything much to round them.
 
That brings an interesting idea to mind.

Just smoothing the splines of a 2pt spline box does not work because there are not enough splines to make all 6 loops. It sort of works if two loops are made at each end of the box with 4 of the 2pt splines smoothed into each loop. And it actually works if there is some extra handwork done, then a fully looped spline box would look like the image below, minus patching one side in the image.

The new 2pt splines were made between the existing control points to make the rest of the splines needed for complete loops for each side of the box, and that was something that I had not thought of until now. It works fine, though the patch sections have to be individually selected by hand and patched because the Easy Spline auto patcher does not patch them correctly all at once by itself.

An interesting shape.

Can the patches have their segment resolution redefined after freezing them?

 
SA9R said:
Can the patches have their segment resolution redefined after freezing them?


No, it's a one way process, so I always freeze them onto a new layer (select your empty layer, then have the Easyspline cage as a background layer and then freeze them). That way you can edit your cage at a later date and redo the freezing if need be.

I love Easyspline, it's a go to tool for mechanical shapes.
Click to expand...
 
..and if there are introduced mistakes, you can use Unfreeze Spline tool to remove unneeded geometry. Unfreeze freezes geometry internally and searches for vertices by position and polygons and deletes them.
 
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