Learn how to simplify spline level of detail in 3ds Max.
- [Instructor] Continuing our exploration of the new Spline modeling tools. Let's take a look at the optimized Spline modifier. As the name indicates, it optimizes level of detail. Reducing the number of knots, while attempting to maintain the shape of the Spline. So that we can see what we're dealing with a little bit better. Let's take a look at this in wire frame. I'll press F4 to enable edged faces. And select the Spline object which I currently have displayed as a renderable Spline in the view port.
And I can see the polygon edges telling me that it's got a pretty consistent level of detail overall. There are some places where it's bunching up, but in general, it's not an optimized Spline. And that's by design. I wanted it that way because I knew I was going to be applying a Spline overlap modifier. Let's take a look at that in the modify panel. I've got some Spline overlaps. And at the bottom is the free-hand. And inside it's interpolation, I've got steps of six.
And I actually did change the optimize setting. I turned that off. So that we wouldn't get any straight segments. Okay, so at the top here, let's go up to our Spline overlap. We've got three of them here to iteratively apply that modifier a few times. For better results. I'm going to enable show knots at the top here. But I can't see the knots inside the object. So let's take a look at this from a more sort of top level view where we can see the knots and not the individual polygons.
I'll right-click in the view port if I need to to give it focus and press F4 to turn off edged faces with the Spline objects still selected, right-click and in the quad menu, choose object properties. And in display properties enable see-through and click okay. And now we have a pretty good idea of the overall shape of these curves. And you can see their thickness. And their knots without being distracted by all of those edges. We can now add the optimize Spline modifier, see how it works.
For the modifier list, looking for optimize Spline. Add that. And once again, enable show knots. And with default settings, it's not going to do much. In fact, the default setting is to reduce the knots by zero percent. As we can see. Zero percent. If I turn the optimize Spline on and off, there's a very tiny subtle change there. Let's play around with this percentage value. We can try a high value like 90.
And press enter. And now, obviously, those Splines are far too smooth. And we're now intersecting more with the geometry. But we did reduce the number of knots. We got some statistics down here. We reduced it by 90 percent. Alright, well let's bring this to something more reasonable. I played with this previously and determined that a good value was 55 percent. The minimum number of knots is just what it sounds like. You can't have fewer than two knots, in this case, on each one of these individual Splines.
If we wanted to increase the overall level of detail, we could set the minimum knots to something high, like 100. And then we get some of that detail back. But I'm going to actually leave it at it's default of two. 'Cause I want to have a pretty heavy optimization here. We can make the result more accurate by increasing the iterations and sub-segment for amateurs here. Iterations is the number of times that this routine will run. We're going to increase it to it's maximum of 16.
And sub-segments is a sampling value. And it's essentially sampling the curve before it runs the optimize. And if you increase the sub-segment up to it's maximum of 10, you will get the best possible results. Okay, we've done some pretty good optimization here. We've knocked it down to 55 percent of it's original number of knots. Let's now check this out in polygon land, once again. Ultimately, since I'm going to render these, the polygon count is more important than the knot count.
So let's go back to the polygon domain. I'll right-click and go into object properties once again. Disable see-through. Click okay. Re-enable edged faces with F4. And now we can see that the polygon object has quite a number of issues with parametrization. Where some of the polygons are very, very large and some are very, very small. Something we couldn't really see when we were not looking at polygons. So let's fix that. We've got, switch here under the create section.
Make adaptive, disable that. And now we have pretty consistent level of detail throughout. We know from the statistics in the optimize Spline modifier, how we've reduced the number of knots. Le's also investigate how we've reduced the overall polygon count. In order to do that, we will need to add a modifier to the top of the stack here. Turn to mesh. And that way we'll be able to make 3D as Mac interpret this as mesh object, rather than a Spline.
Just for the purposes of reading out the statistics. With cursor focus on the view port, press the seven key to activate statistics in the upper left corner. And additionally, let's enable the statistics for the selected object. Click on the plus sign. Going to configure view ports. And in the statistics tab, enable total plus selection. And click okay. And now we got to read out here. We have 247,000 polygons for the selected Spline object.
With the optimized Spline modifier enabled. Let's disable that. And now we have a read out of 550,000 polygons. So we reduced the number of knots by almost half. And also reduced the number of Polygons by almost half. Preserving the overall shape of the Spline. And also helping to redistribute the level of detail. And we're almost ready now to do some low-level vertex editing.
But there's actually one more thing we can do to further help the parametrization, and that is to normalize Spline modifier, which we'll take a look at next week.