Subject:
|
Re: Smoothing on part level using edge lines
|
Newsgroups:
|
lugnet.cad.dev
|
Date:
|
Tue, 6 Aug 2002 18:01:07 GMT
|
Viewed:
|
453 times
|
| |
|
|
In lugnet.cad.dev, Martijn Zwaal writes:
> If you check out the big space dish (3961.dat) you can see the optional line
> algorithm fails because there are no optional lines. In my opinion this part
> is good. There is no need to fix this part because it will only get larger
> and slows down some applications. It performs it's job as it should. This
> is the same with the inside of the hands of the minifigs.
> A workaround in your program could be made by letting your program generate
> optional lines (while preprocessing) on all edges except for edges of color
> 24. You might want to remove optional lines that are coincide with edge
> lines of color 24. That way the other programs are happy and your program
> too. You can use the same code for smoothing but you have to do some extra
> preprocessing.
Reading the various replies to this, I've seen a number of good points, but
I think that some degree of misunderstanding was also generated. I
personally don't think optional lines are generally a good idea on the
inside of curves, but it is true that if a part is ever transparent, then
these are required for fully correct rendering. I don't feel I'm closely
enough involved with the part creation process to have earned an
opinion/vote on this issue, though.
Now as for LDView, I think that Martijn's suggestion of smoothing over all
edges that don't contain an edge line is a good one. There are some
problems that I see that would require being a little smarter, though.
Based on what I've seen with the optional lines, I think that rounding
differences will occasionally cause an edge line to be missed. Adding a
maximum angular difference between two polygons that smoothing will be
disallowed over will help a lot.
Overall, I expect that there will still be some artifacts in this smoothing
process, but I do agree with Martijn that there will be less artifacts than
with the current algorithm.
As for how I would accomplish this in LDView; I can come up with something,
but I doubt it will involve the automatic creation of conditional lines.
While it's true that this would allow me to use my existing smoothing
algorithm, I still don't think it's the best way to go. In fact, based on
the usefullness of the current smoothing code in pointing out missing
conditional lines to part authors, I think I should leave it available as an
option.
> And something else. Have you read my suggestion about rendering patterns
> into a texture map?
I did see that, and it sounds like a good idea, but it would also be fairly
difficult. You would have to have some way of deciding that there are
enough co-planar patterned polygons, then create the texture map, then apply
it in the correct location. All of this is certainly possible, but I'm not
sure how difficult it would be.
There also might be difficulties with the join between the pattern polygons
and the surrounding ones, so you would probably have to consider all the
surrounding co-planar polygons of color 16 to also be part of the pattern.
Given the relative scarcity of patterned parts, I'm not sure the performance
improvements would be enough to justify the amount of work that would be
required.
--Travis Cobbs (tcobbs@REMOVE.halibut.com)
|
|
Message has 1 Reply:
 | | Re: Smoothing on part level using edge lines
|
| "Travis Cobbs" <tcobbs@REMOVE.halibut.com> wrote in message news:H0Fopv.22s@lugnet.com... (...) line (...) part (...) larger (...) This (...) generate (...) color (...) program (...) extra (...) but (...) smoothing (...) than (...) something, (...) (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev)
|
Message is in Reply To:
| | Re: Smoothing on part level using edge lines
|
| If you check out the big space dish (3961.dat) you can see the optional line algorithm fails because there are no optional lines. In my opinion this part is good. There is no need to fix this part because it will only get larger and slows down some (...) (22 years ago, 6-Aug-02, to lugnet.cad.dev)
|
11 Messages in This Thread:
 
 
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
This Message and its Replies on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|
