Would it be possible to do a minor FAQ for the math/physics section? There is a great amount of posts considering the classic point-in-triangle problem. Also there are many posts about wether to use LUTs or Newton-Rhapson iterations or the actual FPU commands for sin/cos/sqrt. The latter is especially bad because it''s quite opinion-based - the thread just keeps gathering comments and it will stay on the front page for simply too long. - Mikko Kauppila

I would gladly help contribute to that with my sparse amount of knowledge.



Bugle4d

You might want to check out the comp.graphics.algorithms FAQ. It covers many of the topics covered in this section, and it'' size shows that any decent FAQ is far from minor. It would be pointless to put a lot of work into a FAQ just to reproduce the work already done.

A lil'' off topic but:

ocw.mit.edu

MIT has a few math courses on there. If you don''t already know, they''ve release a BUNCH of course materials. Lectures, syllabi, readings, charts, java applets to play with. There''s some good math stuff there.

quote:

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Original post by uutee
Would it be possible to do a minor FAQ for the math/physics section? There is a great amount of posts considering the classic point-in-triangle problem. Also there are many posts about wether to use LUTs or Newton-Rhapson iterations or the actual FPU commands for sin/cos/sqrt. The latter is especially bad because it''s quite opinion-based - the thread just keeps gathering comments and it will stay on the front page for simply too long.

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There actually is a FAQ for this forum, found at the link below (and also from a link at the top of the thread list). But it does not yet cover answers to these common problems you mention. It currently provides some guidelines for the appropriate use of the forum.

Forum FAQ

Your idea is actually a fantastic idea. The moderators of this site have discussed including discussion of true FAQ''s in the past, and we''d do exactly as you suggest.

There are a couple of problems.

First, it seems people don''t really even notice the forum FAQ''s. Your post is a case in point. Did you know the FAQ existed before I told you?

Second, it takes time to develop a FAQ. I developed the current FAQ, and I''ve evolved it somewhat over time. I am perfectly willing to add new things to it, but even with other folks helping (I truly appreciate the offer, it will require a lot of my time to edit contributions, moderate discussions about the way certain things are presented (we couldn''t make everyone happy on things like sin/cos evaluation that, as you say, largely generate opinion-based discussions), etc.

The current idea is that eventually, one of these days, the forum software will be replaced. The current software is becoming more and more problematic as the # of posts grows and discussions/plans are underway to make the change. WHEN that happens, we are hoping to be able to have per-forum sticky posts that will sit at the top of the thread list. It would then, in theory, be possible to have sticky posts for a number (maybe only 3 or 4 different ones) of common questions, such as point-in-polygon. These sticky posts would be highlighted in bold and maybe another color so they will be easy and obvious to see.

That said, I have a suggestion. Why don''t I start a thread where people can specifically suggest topics for a true FAQ. The rule for posting a new topic is that if you post a topic, you also must post a link to one or more web sites that provide de-facto standard solutions to problems or one or more links to past gamedev.net threads discussing a topic. The idea here is that I''m willing to spend some time updating the FAQ as long as we''re exploiting existing solutions and discussions, rather than generating all new material that has to be edited, cleaned up, scrutinized, etc.

How does that sound? I''ll actually start the process by adding a new FAQ for the point-in-polygon problem. I''ll link to my standard web-link for this problem, and perhaps a couple of gamedev threads.

Graham Rhodes
Senior Scientist
Applied Research Associates, Inc.

I''ve added a couple of "Technical FAQ''s" to the forum FAQ:

Forum FAQ

These are both dealing with point-in-polygon, because that topic (and web links) are fresh on my mind. I''m actually going to be pretty darned busy for the next couple of weeks---we have a beta test coming up soon, so I won''t get around to starting a thread to suggest new FAQ topics until after that, mid-November-ish, most likely.

Graham Rhodes
Senior Scientist
Applied Research Associates, Inc.

This link recently showed up in a question here.

http://www.cs.ualberta.ca/~andreas/math/matrfaq_latest.html

I havn`t taken the time to examine it; however, its gone through some revisions and coners a great deal of material.

The directory also holds a coordinate system/vector faq.

You might consider adding it to your standard link bag. :D

Bugle4d

I just checked the FAQ; if you start writing a comment next to every link, it''s going to take you a while. IMO, any worthwhile thread that thoroughly discusses a frequently (or even not-so-frequently) asked question should be put in the FAQ. For example:

Math Forum FAQ

General

What kind of math do I need to do 3D games?

...

Geometry

How do I find the angle between two vectors?
How do I use the plane equation
How do I do collision detection
- line/triangle
- triangle/triangle
- sphere/plane

...

You get the idea. It doesn''t have to be done all at once. We''re going to answer the "How do I find the angle between two vectors?" question one last time, then put a link to the thread in the FAQ, and answer "Read the FAQ!" from then on.

Anyway, that''s how I see it... It''s good that something has been done already, though

Cédric

As long as we''re listing topics that come up frequently:

1) Line-line intersection (let''s not forget the basics )
2) Working with timesteps (to be narrowed down...)
3) Velocity/Acceleration/Mechanics in general (also to be narrowed down )
4) Rotations and other operations with Matrices
5) Quanternions
6) Basic vector FAQ
7) Finding the height on a triangle (I see this one all the time)
8) Physics SDKS
9) Basic formulas (Pythag., Law of Sines/Cosines, Dot Product, Cross product, etc.)
10) Anything I didn''t list

To grhodes: I was very aware of the existence of the FAQ before starting the thread - IMHO the FAQ is quite visible on the forum. I also knew of its lack of information considering the actual mathematical and physical questions.

You''re correct, it''s hard to find people who are willing to write a FAQ. Therefore I second johnb''s opinion of adding the comp.graphics.algorithms FAQ link to the forum FAQ, possibly with some sidewords ("here you can find the answers for the most usual problems like...")

- Mikko Kauppila