SM and movement

roland · 09-01-2018, 01:00 PM

Where can I find the correlation between the movement and the size modifier?

Thanks

Anthony · 09-01-2018, 01:23 PM

That's easy: there isn't one built into the game system, though you can certainly buy extra move and claim it's because of long legs.

roland · 09-01-2018, 01:28 PM

So if I have a giant 30 feet tall I do not know exactly how many yards it covers per second.
It seems strange to me that such a precise system like GURPS does not have this rule. But nothing is written in the Basic Set or in Pyramid 77 .....

Imion · 09-01-2018, 01:45 PM

Quote:

Originally Posted by roland

So if I have a giant 30 feet tall I do not know exactly how many yards it covers per second.
(...)

Of corse you do. Just look at it's Move. ;)

As Anthony said: Size Modifier does not provide increased Basic or Enhanced Move. You will have to buy that separately if the giant is a PC. If you build it as a monster just pick a Move score that seems appropriate.

Stormcrow · 09-01-2018, 01:47 PM

GURPS isn't a reality simulator (I keep saying this lately). You can't plug in game statistics and discover emergent properties by observing the game elements.

If you want to move faster, you increase your Basic Move. If you want to be much taller, you increase your Size Modifier. By making these separate statistics, you can change one independently of the other. YOU decide what your character can do, and pick the statistics that do it. GURPS won't do it for you.

Refplace · 09-01-2018, 01:49 PM

That is because SM does not affect movement.
The idea is that something big may move very slowly or fast depending so GURPS does not tie them together.
A giant jellyfish for example still just floats along.
It may seem counter intuitive but by not bundling them it gives the GM greater precision and control over his designs.

roland · 09-01-2018, 01:55 PM

So...... for it to seem realistic..... My giant who has a normal speed.... what movement should it have?

whswhs · 09-01-2018, 02:23 PM

What I use as a rule of thumb is that Basic Move is proportional to the square root of body height/length. This is ignoring variations in gravity (I don't run many campaigns set on other planets) and in body design (effectively, treating all animals as humanoids); you can look up movement speeds for other species and use them as a baseline if you want.

So, for example, in my current campaign, the race of nixies are "three-quarterlings" with SM -1, and average 70% of human height. The square root of 0.7 is 0.84. If you multiply human Basic Move of 5 by 0.84, you get 4.20, which rounds down to 4. So nixies have -1 to Basic Move as a racial trait.

This isn't a GURPS rule. But it will get you roughly reasonable estimates if you want to work with somewhat realistic biomechanics.

On the other hand, if you want to get fairy tale or movie giants, who move just like humans despite being much bigger, you could change Basic Move in proportion to height/length. So if you had a giant who stood 20' tall (roughly SM +2), his height would be about 3.3x human, and multiplying Basic Move 5 x3.3 gives you 16.5. So you could give him, say, +10 Basic Move as a racial trait. This is a different rule for a different type of storytelling.

Anthony · 09-01-2018, 02:55 PM

Quote:

Originally Posted by roland

So...... for it to seem realistic..... My giant who has a normal speed.... what movement should it have?

For a cinematic giant that ignores the square/cube law, treat as a pendulum and speed varies with the square root of height. For realistic giants, it's more like the tenth root of height.

Humabout · 09-02-2018, 09:39 AM

Quote:

Originally Posted by roland

So if I have a giant 30 feet tall I do not know exactly how many yards it covers per second.
It seems strange to me that such a precise system like GURPS does not have this rule. But nothing is written in the Basic Set or in Pyramid 77 .....

In real life, size is very much NOT correlated to speed. Take, for instance, a SM 0 cheetah with a top Move of about 30 and the SM 8 crawler-transporter at NASS KSC with its 1 mile per hour, or half a yard per second. GURPS can model both with advantages.

This is one reason they are decoupled. Size does not imply speed. If you are concerned with biological relationships, it still doesn't hold. Cheetahs are faster than SM 3 elephants, too. Really, your best bet is to just pick something that fits your vision.

09-01-2018, 01:00 PM	#1
roland Join Date: Jun 2006	SM and movement Where can I find the correlation between the movement and the size modifier? Thanks

09-01-2018, 01:23 PM	#2
Anthony Join Date: Feb 2005 Location: Berkeley, CA	Re: SM and movement That's easy: there isn't one built into the game system, though you can certainly buy extra move and claim it's because of long legs. __________________ My GURPS site and Blog.

09-01-2018, 01:28 PM	#3
roland Join Date: Jun 2006	Re: SM and movement So if I have a giant 30 feet tall I do not know exactly how many yards it covers per second. It seems strange to me that such a precise system like GURPS does not have this rule. But nothing is written in the Basic Set or in Pyramid 77 .....

09-01-2018, 01:47 PM	#5
Stormcrow Join Date: Aug 2004 Location: Ronkonkoma, NY	Re: SM and movement GURPS isn't a reality simulator (I keep saying this lately). You can't plug in game statistics and discover emergent properties by observing the game elements. If you want to move faster, you increase your Basic Move. If you want to be much taller, you increase your Size Modifier. By making these separate statistics, you can change one independently of the other. YOU decide what your character can do, and pick the statistics that do it. GURPS won't do it for you.

09-01-2018, 01:49 PM	#6
Refplace Join Date: Nov 2008 Location: Yukon, OK	Re: SM and movement That is because SM does not affect movement. The idea is that something big may move very slowly or fast depending so GURPS does not tie them together. A giant jellyfish for example still just floats along. It may seem counter intuitive but by not bundling them it gives the GM greater precision and control over his designs. __________________ My GURPS publications GURPS Powers: Totem and Nature Spirits; GURPS Template Toolkit 4: Spirits; Pyramid articles. Buying them lets us know you want more! My GURPS fan contribution and blog: REFPLace GURPS Landing Page My List of GURPS You Tube videos (plus a few other useful items) My GURPS Wiki entries

09-01-2018, 01:55 PM	#7
roland Join Date: Jun 2006	Re: SM and movement So...... for it to seem realistic..... My giant who has a normal speed.... what movement should it have?

09-01-2018, 02:23 PM	#8
whswhs Join Date: Jun 2005 Location: Lawrence, KS	Re: SM and movement What I use as a rule of thumb is that Basic Move is proportional to the square root of body height/length. This is ignoring variations in gravity (I don't run many campaigns set on other planets) and in body design (effectively, treating all animals as humanoids); you can look up movement speeds for other species and use them as a baseline if you want. So, for example, in my current campaign, the race of nixies are "three-quarterlings" with SM -1, and average 70% of human height. The square root of 0.7 is 0.84. If you multiply human Basic Move of 5 by 0.84, you get 4.20, which rounds down to 4. So nixies have -1 to Basic Move as a racial trait. This isn't a GURPS rule. But it will get you roughly reasonable estimates if you want to work with somewhat realistic biomechanics. On the other hand, if you want to get fairy tale or movie giants, who move just like humans despite being much bigger, you could change Basic Move in proportion to height/length. So if you had a giant who stood 20' tall (roughly SM +2), his height would be about 3.3x human, and multiplying Basic Move 5 x3.3 gives you 16.5. So you could give him, say, +10 Basic Move as a racial trait. This is a different rule for a different type of storytelling. __________________ Bill Stoddard I don't think we're in Oz any more.