Friday, June 24, 2016

Last waves project (probably)

I've posted already about how swell is formed and propagates across the oceans, but it is based on swell created by local conditions.  But in an RPG, we're generally not concerned with the size of the swell created where the PCs are and how far it goes, we're more concerned with the size of the swell generated elsewhere and now arriving where the PCs are.  The system I posted earlier is fine for this, if you're willing as DM to generate weather for the entire world, work out the swell generated in dozens of separate weather systems, and then figure out how much it decays in the distance it has to cover to get to where the PCs are.  If you want to get really technical, you'd have to figure out how long it takes that swell to reach the PCs' area from its source weather system, not to mention all the lesser swells generated by that weather system (it stands to reason if it takes 50 hours to fully develop the waves, that there would be less developed waves created beforehand, which would also travel until they hit a shore). 

No, the best thing to do here, from a game feasibility standpoint, is to work out some sort of statistical stand-in that would take into account all the directions a swell could come from, the likelihood of strong winds somewhere in those directions, and how far the swell generated by those winds would have to come.  Roll some dice to see a generalized picture of the world's weather and go from there.  A simple table wouldn't meet my standards here; the Hawaiian Islands, surrounded by thousands of miles of ocean in all directions, should not get the same results as Galveston, Texas, which only has any kind of long fetch distance to the southeast, and even that gets buffered by Florida, Cuba, and Mexico.  I'll have to figure out some sort of equation, or a table complex enough to take everything into account, but not so complex that it can't be used on the fly if need be. 

I'll probably have to dredge up my old statistics textbooks, too.  If I can't figure out a decent way to math this problem out the smart way, I'm going to have to brute force it, and generate a world's worth of weather for several hundred days, and then figure out what kind of swells that produces in different places.  I'm not entirely sure I want to take on that kind of number crunching if I don't have to.
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Thursday, June 2, 2016

Breaking news

Okay, so these numbers could probably use a little better going-over than I've given them, but like I said, this whole process has been a grind.  I still have my raw numbers for each step of the way, and I have some ideas for how to go back and get better results, but I really need to step away from this for a little while before I attempt any of that.  Besides, I have other nitpicky projects of insane detail to torture myself with.

So, on to the beta version of my official waves-breaking-on-shore tables.  They are three separate tables, representing beach slopes of "steep", "moderate", and "mild".  To read the table, cross reference the wave period across the top and wave height down the left side.  The entry for any given height and period will give you the wave height at the point the wave breaks (waves tend to get higher as they approach shore and their energy is concentrated into a shallower column of water), the water depth at the point the wave breaks, and the form the wave breaks into.  The types of breakers are Spilling (Sp), Plunging (P), and Surging (Su).  Spilling breakers are the gentlest of the three, with the top of the wave literally spilling down the front with minimal turbulence.  Plunging breakers are the classic surfers' curl, and surging breakers are just a huge turbulent mess smashing into the shore.  This video has a decent example of each type.


Steep sloped beach (1 foot rise per 10 feet horizontal distance)

 
ht \period-> 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
2 2/3/Sp 2/2/P 3/2/P 3/2/P 3/3/P 4/3/Su 4/3/Su 4/3/Su 4/4/Su 5/4/Su 5/4/Su 5/3/Su 5/4/Su 5/5/Su 5/5/Su
3 3/5/Sp 3/4/P 4/4/P 4/3/P 5/3/P 5/4/P 5/4/Su 6/4/Su 6/5/Su 6/5/Su 7/5/Su 7/5/Su 7/6/Su 7/6/Su 8/6/Su
4      4/5/Sp 5/5/P 5/5/P 6/5/P 6/5/P 7/5/P 7/5/Su 7/6/Su 8/6/Su 8/6/Su 8/7/Su 9/7/Su 10/7/Su 10/7/Su
5

6/6/P 6/6/P 7/6/P 7/6/P 8/6/P 9/6/P 9/7/Su 9/7/Su 10/7/Su 10/8/Su 11/8/Su 11/8/Su 11/9/Su
6

7/7/Sp 7/7/P 8/7/P 8/7/P 9/7/P 10/7/P 10/8/P 10/8/Su 11/8/Su 11/9/Su 12/9/Su 13/9/Su 13/10/Su
7

7/8/Sp 8/8/P 9/8/P 9/8/P 10/8/P 11/9/P 11/9/P 11/9/P 12/10/Su 13/10/Su 13/10/Su 14/10/Su 15/11/Su
8

9/11/Sp 9/9/P 10/9/P 10/9/P 11/9/P 12/11/P 12/10/P 12/10/P 14/11/P 14/11/Su 14/11/Su 15/11/Su 16/12/Su
9

9/12/Sp 10/11/Sp 10/11/P 11/10/P 12/11/P 13/12/P 13/11/P 14/11/P 15/12/P 15/12/P 16/13/Su 16/13/Su 17/13/Su
10

10/12/Sp 11/12/Sp 11/12/P 12/11/P 13/12/P 14/13/P 14/12/P 15/12/P 16/12/P 17/13/P 17/14/P 17/15/Su 18/15/Su
11


12/13/Sp 12/13/P 13/12/P 14/13/P 15/14/P 15/13/P 16/13/P 17/13/P 18/14/P 19/15/P 19/16/Su 20/16/Su
12


13/17/Sp 13/14/P 14/14/P 15/14/P 16/15/P 16/14/P 17/15/P 18/14/P 19/15/P 20/16/P 20/17/P 21/17/Su
13


13/18/Sp 14/16/Sp 15/16/P 16/15/P 17/16/P 17/16/P 19/16/P 19/16/P 20/16/P 21/17/P 22/17/P 22/18/P
14


14/19/Sp 15/18/Sp 16/17/P 17/16/P 18/17/P 18/17/P 20/17/P 20/18/P 22/18/P 22/18/P 23/18/P 24/19/P
15


15/19/Sp 16/19/Sp 17/18/P 18/18/P 18/18/P 19/18/P 21/18/P 22/19/P 23/19/P 23/18/P 24/19/P 25/20/P
16


16/20/Sp 17/22/Sp 18/19/P 19/20/P 19/19/P 20/19/P 22/19/P 23/20/P 24/20/P 25/20/P 25/20/P 26/20/P
17



18/25/Sp 19/20/P 20/21/P 20/19/P 21/20/P 23/20/P 25/21/P 25/22/P 26/21/P 26/21/P 27/21/P
18



19/26/Sp 20/21/Sp 21/22/P 21/20/P 22/21/P 24/21/P 25/22/P 26/23/P 27/23/P 28/23/P 28/22/P
19



20/27/Sp 20/23/Sp 22/23/P 22/21/P 23/22/P 25/22/P 26/23/P 27/24/P 28/24/P 29/24/P 29/23/P
20



20/28/Sp 21/25/Sp 23/23/P 23/23/P 24/23/P 26/23/P 26/24/P 28/24/P 29/25/P 30/25/P 31/24/P
21



21/31/Sp 22/27/Sp 24/24/P 24/24/P 25/24/P 26/24/P 27/25/P 29/25/P 30/26/P 31/26/P 33/25/P
22



22/34/Sp 23/29/Sp 24/26/P 25/25/P 26/26/P 27/25/P 29/26/P 30/26/P 31/27/P 32/27/P 34/27/P
23



23/37/Sp 23/31/Sp 25/28/Sp 26/26/P 27/28/P 28/26/P 30/27/P 31/27/P 32/28/P 33/29/P 35/28/P
24



24/40/Sp 24/32/Sp 26/30/Sp 27/27/P 28/29/P 29/27/P 31/28/P 32/28/P 33/29/P 35/30/P 36/30/P
25



25/43/Sp 25/35/Sp 26/31/Sp 28/28/P 29/30/P 30/28/P 31/28/P 33/29/P 34/30/P 36/31/P 37/31/P
26



26/46/Sp 26/37/Sp 27/33/Sp 29/29/P 30/31/P 31/30/P 32/29/P 34/30/P 35/31/P 38/32/P 38/33/P
27



27/46/Sp 27/39/Sp 28/35/Sp 30/31/P 31/32/P 32/31/P 33/30/P 35/31/P 36/32/P 38/33/P 39/34/P
28



28/46/Sp
29/37/Sp 31/33/P 32/33/P 32/32/P 34/31/P 36/32/P 37/33/P 39/34/P 41/35/P
29



29/47/Sp
30/39/Sp 32/35/Sp 33/34/P 33/33/P 35/32/P 37/33/P 38/34/P 39/35/P 42/36/P
30



30/47/Sp
30/41/Sp 33/35/Sp 34/35/P 34/35/P 36/33/P 38/34/P 39/35/P 40/36/P 43/37/P
31



31/47/Sp
31/43/Sp 33/38/Sp 35/36/P 36/37/P 37/35/P 38/35/P 40/36/P 41/37/P 43/38/P
32



32/48/Sp
32/46/Sp 34/40/Sp 36/37/P 37/37/P 38/37/P 39/36/P 41/37/P 42/38/P 44/39/P
33



33/48/Sp
33/48/Sp 35/42/Sp 37/39/P 38/38/P 39/38/P 40/37/P 42/38/P 43/39/P 45/40/P
34



34/48/Sp
34/50/Sp 36/43/Sp 38/41/P 39/39/P 40/40/P 41/38/P 43/39/P 44/40/P 45/41/P
35






37/44/Sp 39/43/Sp 40/40/P 41/42/P 42/39/P 44/40/P 45/41/P 46/42/P
36






38/45/Sp 40/44/Sp 41/41/P 42/43/P 43/40/P 44/41/P 47/42/P 47/43/P
37






38/46/Sp 41/45/Sp 43/43/P 43/45/P 44/42/P 45/42/P 48/43/P 48/44/P
38






39/47/Sp 41/47/Sp 44/44/P 44/46/P 45/43/P 46/43/P 49/44/P 49/45/P
39






39/48/Sp 42/49/Sp 45/46/P 45/47/P 46/45/P 47/44/P 49/45/P 51/46/P
40






40/49/Sp 42/50/Sp 45/47/P 46/48/P 46/46/P 48/45/P 50/46/P 52/47/P
41






41/50/Sp 43/51/Sp 46/49/P 47/49/P 47/48/P 49/47/P 51/47/P 53/48/P
42






42/52/Sp 44/51/Sp 46/50/P 48/50/P 48/49/P 50/49/P 51/48/P 55/49/P
43






43/54/Sp 45/52/Sp 47/51/Sp 49/51/P 49/50/P 51/50/P 52/49/P 55/50/P
44







46/52/Sp 48/53/Sp 50/52/P 50/52/P 52/52/P 53/50/P 56/51/P
45







47/53/Sp 49/54/Sp 52/52/P 52/53/P 53/54/P 54/51/P 56/52/P
46







48/53/Sp 49/56/Sp 53/53/P 53/54/P 54/56/P 55/52/P 57/53/P
47








50/57/Sp 54/55/P 54/55/P 55/58/P 56/52/P 57/54/P
48








50/59/Sp 54/56/P 55/56/P 56/59/P 57/54/P 58/55/P
49








51/60/Sp 55/58/P 56/57/P 57/60/P 59/55/P 59/56/P
50








53/62/Sp 55/60/P 58/59/P 58/61/P 60/57/P 60/57/P
51








54/63/Sp 56/61/Sp 59/60/P 59/62/P 60/58/P 61/58/P
52








55/65/Sp 57/63/Sp 60/61/P 60/63/P 61/60/P 63/59/P
53









58/64/Sp 61/63/P 61/64/P 61/61/P 64/61/P
54









59/66/Sp 62/65/P 62/65/P 62/63/P 65/63/P
55









60/67/Sp 63/67/P 63/66/P 63/64/P 66/65/P
56









61/68/Sp 63/69/P 65/67/P 65/66/P 67/67/P
57










64/70/P 66/68/P 66/67/P 68/69/P
58










65/72/P 67/69/P 67/69/P 69/71/P
59










65/74/P 68/70/P 68/70/P 69/73/P
60











69/71/P 69/71/P 70/75/P
61











70/71/P 70/72/P 70/77/P
62












71/73/P 71/79/P

A few things to note here: First of all, there are entries in the table for waves with long periods and very small heights.  This is due to degradation of the wave height over long distances, as discussed in this post.  Also, there are fewer entries for waves of period 7 than for period 6.  This post on wave generation shows that winds strong enough to generate waves of this period tend to build rapidly on to higher periods rather than higher waves of period 7.  Weird, I know.  Lastly, if you look at waves of a given height and how they are affected by period, you'll see some places where the outcomes (mostly breaker height or depth) will go up as period increases, and then go down as it increases some more.  Sometimes it wavers wildly as you look across the table.  Part of this is due to natural weirdness of waves -- the complexity of the interaction between the wave and the ocean floor -- but most of it is due to rounding errors on my part, in many cases errors being carried forward and compounded from one step of the process to the next.  I did some eyeball quality control before posting these tables, and I think I can get better numbers after another go at it, but like I said, I need to step away from this for a bit.  These numbers are "close enough" numbers for gaming purposes, not so much to be referred to and treated as gospel as to provide a baseline for a more accurate ruling by a GM.  Even if, ultimately, you're just pulling numbers out of your ass in the heat of the moment, it comes out as more realistic if your numbers have some connection to reality...

Okay, next table...

Moderate sloped beach (1 foot rise per 20 feet horizontal distance)

ht \period-> 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
2 2/3/Sp 2/2/Sp 3/2/P 3/3/P 3/3/P 3/3/P 4/3/P 4/4/P 4/4/P 5/4/P 5/4/P 5/4/P 5/5/P 5/5/P 5/6/P
3 3/5/Sp 3/4/Sp 3/4/P 4/4/P 4/4/P 5/4/P 5/4/P 5/5/P 6/5/P 6/6/P 6/6/P 7/5/P 7/6/P 7/6/P 8/7/P
4
4/6/Sp 4/5/Sp 5/5/P 5/5/P 6/5/P 7/5/P 7/6/P 7/7/P 8/7/P 8/7/P 8/8/P 8/8/P 9/8/P 9/8/P
5

6/6/Sp 6/6/Sp 6/7/P 7/6/P 8/6/P 8/7/P 8/8/P 9/8/P 9/8/P 10/9/P 10/9/P 11/9/P 11/10/P
6

7/7/Sp 7/7/Sp 7/8/P 8/7/P 8/7/P 9/8/P 10/9/P 10/9/P 10/9/P 11/10/P 11/10/P 12/10/P 12/11/P
7

8/9/Sp 8/8/Sp 8/9/P 9/9/P 9/8/P 10/9/P 11/10/P 11/10/P 12/10/P 12/11/P 13/12/P 13/12/P 14/12/P
8

8/11/Sp 9/10/Sp 9/10/Sp 10/10/P 11/8/P 11/10/P 12/11/P 12/11/P 13/11/P 14/12/P 14/13/P 14/14/P 15/13/P
9

9/12/Sp 10/11/Sp 10/11/Sp 10/11/P 12/10/P 12/12/P 13/12/P 14/13/P 15/14/P 15/13/P 15/14/P 15/15/P 16/15/P
10

9/12/Sp 11/13/Sp 11/13/Sp 11/13/Sp 13/13/P 13/13/P 14/13/P 15/14/P 16/17/P 16/15/P 17/15/P 17/16/P 17/16/P
11


12/14/Sp 12/14/Sp 12/14/Sp 14/15/P 14/14/P 15/15/P 16/15/P 17/17/P 17/17/P 18/17/P 18/16/P 19/17/P
12


12/15/Sp 13/15/Sp 13/15/Sp 14/16/P 15/15/P 16/16/P 17/17/P 18/18/P 19/19/P 19/18/P 20/17/P 20/18/P
13


13/16/Sp 14/16/Sp 14/16/Sp 15/17/Sp 16/16/P 17/17/P 18/18/P 19/18/P 20/20/P 20/20/P 21/19/P 21/19/P
14


13/17/Sp 14/18/Sp 15/17/Sp 16/17/Sp 17/17/P 18/18/P 19/19/P 20/19/P 21/20/P 22/21/P 22/21/P 23/20/P
15


14/18/Sp 15/19/Sp 17/19/Sp 17/18/Sp 17/18/P 19/20/P 20/20/P 21/20/P 22/21/P 23/23/P 23/23/P 25/22/P
16


14/19/Sp 17/21/Sp 18/20/Sp 18/20/Sp 18/20/P 20/21/P 21/21/P 22/21/P 23/21/P 24/23/P 25/25/P 26/24/P
17



18/24/Sp 19/21/Sp 19/20/Sp 19/21/Sp 21/22/P 22/22/P 23/22/P 24/22/P 25/24/P 26/27/P 27/25/P
18



18/25/Sp 19/21/Sp 20/21/Sp 20/22/Sp 21/23/P 23/23/P 24/23/P 25/23/P 26/24/P 27/27/P 28/27/P
19



19/26/Sp 20/23/Sp 21/23/Sp 21/23/Sp 22/24/P 24/24/P 25/24/P 26/24/P 27/25/P 28/28/P 28/28/P
20



20/27/Sp 20/25/Sp 22/25/Sp 22/24/Sp 23/26/Sp 25/25/P 26/25/P 27/25/P 28/25/P 29/28/P 29/30/P
21



21/28/Sp 21/27/Sp 23/26/Sp 23/25/Sp 24/27/Sp 26/26/P 27/26/P 28/26/P 29/26/P 30/29/P 30/30/P
22



22/30/Sp 22/30/Sp 24/27/Sp 24/26/Sp 25/28/Sp 26/27/P 29/28/P 29/27/P 30/28/P 31/29/P 31/31/P
23



23/32/Sp 23/33/Sp 25/28/Sp 25/28/Sp 26/29/Sp 27/28/P 30/29/P 30/28/P 31/29/P 32/29/P 32/31/P
24



24/34/Sp 24/34/Sp 26/30/Sp 26/29/Sp 27/30/Sp 28/29/P 30/30/P 31/30/P 32/31/P 33/31/P 33/32/P
25



25/36/Sp 25/36/Sp 26/31/Sp 28/31/Sp 28/32/Sp 29/31/Sp 31/31/P 33/32/P 33/32/P 34/32/P 34/32/P
26



26/38/Sp 26/37/Sp 27/33/Sp 29/32/Sp 29/33/Sp 30/32/Sp 31/32/P 34/33/P 34/33/P 35/33/P 35/33/P
27



27/40/Sp 28/38/Sp 28/36/Sp 30/33/Sp 30/34/Sp 31/33/Sp 32/33/P 35/35/P 35/34/P 36/34/P 36/33/P
28



28/42/Sp
31/39/Sp 31/34/Sp 31/35/Sp 31/34/Sp 33/34/P 36/36/P 36/35/P 37/35/P 38/35/P
29



29/44/Sp
32/41/Sp 32/35/Sp 32/36/Sp 32/35/Sp 34/35/Sp 36/37/P 38/37/P 38/36/P 39/36/P
30



30/46/Sp
33/43/Sp 32/37/Sp 33/37/Sp 33/36/Sp 35/37/Sp 37/38/P 39/38/P 39/37/P 40/37/P
31



31/47/Sp
33/43/Sp 33/38/Sp 34/39/Sp 34/37/Sp 36/39/Sp 37/39/P 40/40/P 40/39/P 41/39/P
32



32/48/Sp
34/45/Sp 33/40/Sp 35/40/Sp 35/38/Sp 37/40/Sp 38/40/P 40/41/P 42/41/P 42/40/P
33



33/49/Sp
34/47/Sp 34/42/Sp 36/41/Sp 36/40/Sp 37/41/Sp 38/41/P 41/42/P 43/42/P 43/41/P
34



34/50/Sp
35/50/Sp 35/44/Sp 37/42/Sp 37/42/Sp 38/42/Sp 39/42/Sp 42/43/P 44/43/P 44/43/P
35






36/46/Sp 38/43/Sp 38/44/Sp 39/43/Sp 40/44/Sp 43/44/P 45/44/P 45/44/P
36






40/52/Sp 39/44/Sp 40/45/Sp 40/44/Sp 41/45/Sp 43/45/P 46/46/P 47/46/P
37






41/54/Sp 40/46/Sp 41/46/Sp 41/45/Sp 43/46/Sp 44/46/P 47/48/P 48/47/P
38






42/56/Sp 40/47/Sp 42/47/Sp 42/47/Sp 43/47/Sp 44/47/P 48/49/P 49/48/P
39






43/58/Sp 41/48/Sp 43/48/Sp 43/48/Sp 44/48/Sp 45/48/P 48/50/P 51/50/P
40






44/60/Sp 41/49/Sp 44/49/Sp 44/49/Sp 44/48/Sp 46/50/Sp 49/51/P 52/52/P
41






44/60/Sp 42/51/Sp 45/50/Sp 45/51/Sp 45/49/Sp 47/51/Sp 49/52/P 53/53/P
42






45/62/Sp 43/53/Sp 46/51/Sp 46/52/Sp 46/50/Sp 48/52/Sp 50/53/P 53/54/P
43






45/62/Sp 44/55/Sp 47/52/Sp 47/53/Sp 47/51/Sp 49/53/Sp 50/54/P 54/56/P
44







48/60/Sp 48/53/Sp 48/54/Sp 48/52/Sp 50/54/Sp 51/55/P 55/57/P
45







49/63/Sp 48/54/Sp 49/56/Sp 49/53/Sp 51/55/Sp 52/56/Sp 56/58/P
46







50/67/Sp 49/56/Sp 50/57/Sp 50/54/Sp 52/56/Sp 53/58/Sp 56/59/P
47








49/58/Sp 52/58/Sp 52/56/Sp 52/57/Sp 54/59/Sp 57/60/P
48








50/60/Sp 53/59/Sp 53/57/Sp 53/58/Sp 55/60/Sp 57/61/P
49








50/61/Sp 54/60/Sp 54/58/Sp 54/59/Sp 56/61/Sp 58/62/P
50








51/62/Sp 55/61/Sp 55/60/Sp 55/61/Sp 57/62/Sp 58/63/P
51








52/63/Sp 56/62/Sp 56/61/Sp 56/63/Sp 58/63/Sp 59/64/P
52








53/64/Sp 57/63/Sp 57/62/Sp 57/64/Sp 58/63/Sp 60/66/Sp
53









58/66/Sp 58/63/Sp 58/65/Sp 59/64/Sp 61/67/Sp
54









60/69/Sp 60/65/Sp 60/67/Sp 60/65/Sp 62/69/Sp
55









61/72/Sp 61/67/Sp 61/68/Sp 61/66/Sp 63/70/Sp
56









62/74/Sp 62/68/Sp 62/69/Sp 62/67/Sp 64/71/Sp
57










63/70/Sp 63/70/Sp 63/68/Sp 65/73/Sp
58










64/72/Sp 64/72/Sp 64/69/Sp 66/74/Sp
59










65/74/Sp 65/73/Sp 65/69/Sp 66/75/Sp
60











66/74/Sp 66/70/Sp 67/76/Sp
61











67/76/Sp 67/70/Sp 67/77/Sp
62












68/71/Sp 68/79/Sp


And finally...
Mild sloped beach (1 foot rise per 50 feet horizontal distance)

ht \period-> 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
2 2/3/Sp 2/2/Sp 3/2/P 3/3/P 3/3/P 3/4/P 3/4/P 3/4/P 4/5/P 4/5/P 4/4/P 4/4/P 4/5/P 4/6/P 4/7/P
3 3/4/Sp 3/4/Sp 3/4/Sp 4/4/P 4/4/P 4/4/P 4/5/P 5/5/P 5/6/P 5/6/P 6/6/P 6/6/P 6/6/P 7/7/P 7/7/P
4
4/7/Sp 4/5/Sp 4/5/Sp 5/5/P 5/6/P 5/6/P 6/6/P 6/7/P 6/7/P 7/8/P 7/8/P 7/8/P 8/8/P 8/8/P
5

5/6/Sp 5/6/Sp 6/6/P 6/7/P 6/8/P 7/8/P 7/8/P 8/8/P 8/9/P 8/10/P 9/10/P 9/10/P 9/11/P
6

6/7/Sp 6/8/Sp 7/8/Sp 7/8/P 7/9/P 8/10/P 8/10/P 9/9/P 9/10/P 10/11/P 10/11/P 10/11/P 10/12/P
7

7/9/Sp 7/9/Sp 7/9/Sp 8/9/P 8/9/P 9/10/P 9/11/P 10/11/P 10/11/P 11/12/P 11/12/P 11/13/P 12/13/P
8

8/10/Sp 8/10/Sp 8/10/Sp 9/10/Sp 9/10/P 10/11/P 10/12/P 11/12/P 11/13/P 12/14/P 12/13/P 13/14/P 13/14/P
9

8/11/Sp 9/11/Sp 9/11/Sp 10/11/Sp 10/11/P 11/12/P 11/13/P 12/14/P 12/14/P 13/15/P 13/14/P 14/15/P 14/15/P
10

9/12/Sp 10/12/Sp 10/13/Sp 11/13/Sp 11/12/P 12/13/P 12/14/P 13/15/P 13/15/P 14/17/P 14/15/P 15/16/P 16/16/P
11


10/13/Sp 10/14/Sp 12/14/Sp 12/14/Sp 12/14/P 13/15/P 14/16/P 14/16/P 15/18/P 15/17/P 16/17/P 17/17/P
12


11/15/Sp 11/15/Sp 12/15/Sp 13/16/Sp 13/15/P 14/16/P 15/17/P 15/17/P 16/19/P 16/19/P 17/19/P 18/19/P
13


12/16/Sp 12/16/Sp 13/16/Sp 14/16/Sp 14/17/Sp 15/17/P 16/17/P 16/18/P 17/20/P 17/20/P 18/20/P 19/20/P
14


13/17/Sp 13/17/Sp 13/17/Sp 15/17/Sp 15/18/Sp 16/17/P 17/18/P 17/19/P 18/21/P 18/21/P 19/22/P 20/22/P
15


14/18/Sp 14/19/Sp 14/19/Sp 15/19/Sp 16/19/Sp 17/18/Sp 18/19/P 18/20/P 19/22/P 20/23/P 20/24/P 21/24/P
16


14/19/Sp 15/21/Sp 15/20/Sp 16/20/Sp 17/20/Sp 18/19/Sp 18/19/P 19/21/P 20/23/P 21/24/P 21/25/P 22/26/P
17



16/24/Sp 16/21/Sp 17/21/Sp 18/21/Sp 19/21/Sp 19/20/P 20/22/P 21/24/P 22/25/P 22/26/P 23/27/P
18



17/26/Sp 17/22/Sp 17/22/Sp 19/22/Sp 19/22/Sp 20/21/P 21/23/P 22/24/P 22/25/P 23/27/P 24/28/P
19



17/28/Sp 18/23/Sp 18/24/Sp 19/23/Sp 20/24/Sp 21/22/P 22/24/P 23/25/P 23/26/P 24/28/P 25/29/P
20



18/29/Sp 19/25/Sp 19/25/Sp 20/24/Sp 21/26/Sp 22/24/Sp 22/24/P 24/26/P 24/27/P 25/29/P 26/30/P
21



19/30/Sp 20/27/Sp 20/26/Sp 21/25/Sp 22/27/Sp 23/25/Sp 23/25/P 24/26/P 25/27/P 26/30/P 27/31/P
22



20/32/Sp 21/29/Sp 21/27/Sp 22/27/Sp 23/28/Sp 23/26/Sp 24/26/P 25/27/P 26/28/P 27/31/P 28/32/P
23



21/34/Sp 22/31/Sp 22/28/Sp 22/28/Sp 23/29/Sp 24/28/Sp 25/28/P 25/27/P 27/29/P 28/31/P 29/33/P
24



23/35/Sp 23/33/Sp 23/30/Sp 23/29/Sp 24/30/Sp 25/30/Sp 26/29/Sp 26/28/P 28/30/P 29/32/P 29/34/P
25



24/37/Sp 23/35/Sp 24/31/Sp 24/31/Sp 25/31/Sp 26/31/Sp 27/30/Sp 28/29/P 28/30/P 30/33/P 30/35/P
26



25/39/Sp 24/36/Sp 25/33/Sp 25/32/Sp 26/32/Sp 27/32/Sp 28/31/Sp 29/30/P 29/31/P 31/34/P 31/36/P
27



26/39/Sp 24/38Sp 26/42/Sp 26/33/Sp 27/33/Sp 28/33/Sp 28/32/Sp 30/32/P 30/32/P 32/35/P 32/36/P
28



27/40/Sp
27/50/Sp 27/34/Sp 28/35/Sp 28/34/Sp 29/34/Sp 31/34/Sp 31/33/P 32/35/P 34/37/P
29



28/40/Sp
28/48/Sp 28/35/Sp 28/36/Sp 29/35/Sp 30/35/Sp 32/35/Sp 32/34/P 33/36/P 35/38/P
30



29/41/Sp
29/47/Sp 29/37/Sp 29/38/Sp 30/36/Sp 31/37/Sp 33/37/Sp 33/35/P 34/37/P 36/39/P
31



29/41/Sp
29/46/Sp 29/39/Sp 29/39/Sp 31/37/Sp 32/38/Sp 33/38/Sp 34/36/P 34/37/P 36/39/P
32



30/42/Sp
30/47/Sp 30/40/Sp 30/40/Sp 32/39/Sp 33/39/Sp 34/39/Sp 35/38/Sp 35/38/P 37/40/P
33



31/42/Sp
30/48/Sp 31/42/Sp 31/41/Sp 33/40/Sp 34/40/Sp 35/40/Sp 36/40/Sp 36/39/P 37/40/P
34



32/43/Sp
31/50/Sp 32/47/Sp 32/42/Sp 33/41/Sp 35/41/Sp 36/42/Sp 37/41/Sp 37/40/P 38/41/P
35






33/52/Sp 33/43/Sp 34/43/Sp 35/42/Sp 37/44/Sp 37/43/Sp 38/41/P 39/42/P
36






34/57/Sp 34/44/Sp 34/45/Sp 36/43/Sp 38/45/Sp 38/44/Sp 40/43/Sp 40/43/P
37






35/62/Sp 35/45/Sp 35/47/Sp 37/45/Sp 39/46/Sp 39/46/Sp 41/44/Sp 41/44/P
38






36/60/Sp 36/47/Sp 36/48/Sp 38/47/Sp 39/46/Sp 40/47/Sp 42/46/Sp 42/45/P
39






37/58/Sp 37/48/Sp 37/49/Sp 39/48/Sp 40/47/Sp 41/48/Sp 43/47/Sp 43/46/P
40






38/58/Sp 38/50/Sp 38/50/Sp 39/50/Sp 40/48/Sp 42/50/Sp 43/48/Sp 44/47/P
41






38/60/Sp 39/51/Sp 39/51/sp 40/51/Sp 41/49/Sp 43/51/Sp 44/49/Sp 45/49/Sp
42






39/62/Sp 40/56/Sp 40/51/Sp 40/52/Sp 42/50/Sp 44/52/Sp 44/50/Sp 46/50/Sp
43






39/62/Sp 40/61/Sp 41/52/Sp 41/53/Sp 43/51/Sp 45/53/Sp 45/51/Sp 47/52/Sp
44







40/67/Sp 42/53/Sp 42/54/Sp 44/52/Sp 46/54/Sp 46/53/Sp 48/53/Sp
45







41/72/Sp 43/55/Sp 43/56/Sp 45/54/Sp 46/55/Sp 47/55/Sp 48/55/Sp
46







41/77/Sp 44/56/Sp 44/57/Sp 45/55/Sp 47/56/Sp 48/57/Sp 49/56/Sp
47








45/57/Sp 45/58/Sp 46/56/Sp 47/57/Sp 49/58/Sp 49/58/Sp
48








46/58/Sp 46/59/Sp 46/57/Sp 48/58/Sp 50/59/Sp 50/59/Sp
49








47/59/Sp 47/60/Sp 47/58/Sp 49/59/Sp 51/60/Sp 51/60/Sp
50








48/60/Sp 48/61/Sp 48/59/Sp 50/61/Sp 52/61/Sp 53/62/Sp
51








49/62/Sp 49/62/Sp 49/60/Sp 51/63/Sp 53/62/Sp 54/64/Sp
52








50/62/Sp 50/63/Sp 50/61/Sp 52/64/Sp 53/63/Sp 55/66/Sp
53









50/66/Sp 50/62/Sp 52/66/Sp 54/64/Sp 56/68/Sp
54









51/69/Sp 51/63/Sp 53/67/Sp 54/65/Sp 57/69/Sp
55









52/72/Sp 52/65/Sp 53/68/Sp 55/66/Sp 58/71/Sp
56









53/74/Sp 53/67/Sp 54/69/Sp 56/67/Sp 59/72/Sp
57










54/70/Sp 54/70/Sp 57/68/Sp 59/73/Sp
58










55/72/Sp 55/71/Sp 58/69/Sp 60/74/Sp
59










56/74/Sp 56/73/Sp 59/70/Sp 60/75/Sp
60











57/74/Sp 60/71/Sp 61/76/Sp
61











58/76/Sp 61/72/Sp 61/77/Sp
62












62/73/Sp 62/79/Sp

Once a wave breaks, it will reform as a new, smaller wave.  Spilling waves reform at 1/2 their previous height, and plunging waves reform at 1/3.  Surging waves just surge onto the shore and dissipate fully that way.  The new wave will then break according to its new height, and may reform several times before ultimately splashing onto land.

Also keep in mind that sandbars, reefs, and submerged rocks act as localized ocean floor, and waves will break over them even if the depth in the general area is too great for breakers to form.  For example, suppose we have an outcropping of rock 8' below the sea surface, with the surrounding area at a depth of 15' or more, gradually sloping toward shore, when an 8' wave with a period of 10 seconds passes through.   On a mild slope, this wave will break in 12' of water, so it passes normally through most of the area.  The rock outcropping is a steep slope (way more than 1:10 slope, but we only have three tables, for simplicity's sake).  On a steep slope, this wave breaks in 10' of water, rising as high as 12' in a plunging breaker.  A smart sailor will see the breakers in this area and steer well away.

One last point here: the wave heights listed here (and in other wave tables I've published) are measured from the bottom of the lowest point of the wave to the top of the highest point.  The depth listed is a baseline drawn where the water level would be at rest, without wave action.  So in the example above, the water in the 15' depth would vary between 11' (4' less than baseline) and 19' (4' more than baseline) as the 8' waves passed over, and the water over the rocks would vary between 2' and 14' as the waves built to 12' and broke over them.
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