Comments for Essential Math Weblog

Comment on It’s Done by Enric

Enric — Thu, 19 Aug 2010 23:14:46 +0000

If I get the Kindle version is the CD material available for download or another way?

Thanks,

Enric

Comment on Correction: Quaternion Creation by Jordan retro 10

Jordan retro 10 — Mon, 07 Jun 2010 06:48:53 +0000

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Comment on It’s Done by Chris Simmons

Chris Simmons — Sun, 14 Mar 2010 19:32:19 +0000

Actually, @axel, I think the mistake is on p5. The range there should read, “magnitude in the range [1.0,10.0))". p11 is correct as this is a statement only about the leading digit which, indeed, has a range of [1,9].

Comment on Mike Acton Takes on C++ Math Libraries by meysam(Iran)

meysam(Iran) — Mon, 28 Dec 2009 19:26:33 +0000

Nice

Comment on More errata by Jim

Jim — Tue, 27 Oct 2009 03:47:19 +0000

Sorry about the confusion, both are technically correct. The formula as shown in the figure can be thought of as P_{i+1} + 1/3(P_i – P_{i+2}). If you rearrange the terms, you get P_{i+1} – 1/3(P_{i+2} – P_i), which is what is in the text.

Comment on More errata by John

John — Sun, 04 Oct 2009 12:10:01 +0000

Hi,

I may have discovered a mistake in the second edition. On page 456, where it is describing how to automatically generate the control points for bezier piecewise curves, the formula for the second control point is different from that shown in figure 10.14. It would be also be better if figure 10.14 was located above the heading for section 10.2.7

Thanks for a great book

Comment on Angular Dynamics: Matrices or Quaternions? by minorlogic

minorlogic — Thu, 30 Apr 2009 13:14:08 +0000

In my example, we create rotation matrix on every step. So it is not the problem.

Pro:
sheap integration
automatic orthonormalization on EVERY step
Cons:
conversion to matrix and back eat some performance

Comment on Indexed by Jim

Jim — Mon, 22 Dec 2008 02:37:02 +0000

Here are the major differences between the first edition and the second edition:

a) Lars revised the rendering chapters (Geometry and Coloring, Lighting, and Rasterization) to cover vertex and fragment shaders rather than the old fixed function pipeline.
b) As part of that, we added a simple shader interface in our game engine.
c) We also added a DX9 renderer and more discussion of DX9.
d) I wrote a new chapter about probability, basic statistics and random numbers.
e) The remaining chapters were updated, cleaned up, and rearranged in an order that we think makes a little more sense.

Overall, we think the book is much better and more useful for modern renderer development.

As a side note, I’m still puzzled at the lack of reviews for the second edition. For those reading this, feel free to write one — if you like the book.

Comment on Angular Dynamics: Matrices or Quaternions? by Franklin

Franklin — Mon, 15 Dec 2008 18:50:08 +0000

Uh, and what about all the other stuff you need to transform (not just the inertia tensor)? The matrix is way cheaper computationally, and for goodness sake, you don’t have to re-orthonormalize it constantly, especially if you have a proper rotational integrator.

Comment on It’s Done by Axel

Axel — Sun, 16 Nov 2008 13:56:08 +0000

Didn’t found your mail adress, so I post it here.
There is a small error on Page 11.

“…magnitude on range [1,9])” muste be “…magnitude on range [1,10))”
thats how you defined it on page 4.
regards.