Unit - metre ratio?

[NeWsOfTzzz]

Hello, I just started coding my first 3d game ever (it's easier than I ever thought, Irrlicht is already having so many built-in features), I'm wondering what's a standard / widely used units per metre ratio?

I mean the coordinates, I think they're called units. Let's say I start at x: 100, how much should I add to get a metre? x:110?


Why I'm asking: I know that everything is kind of relative in a 3d engine, but I think there is some standard in 3d model creation? And I want to use that standard so I don't have to scale every 3d model I use




.

[wildrj]

I dont think there is a standard think you just model them however you want and scale later in irrEdit or a similar program.

[Halifax]

Most people just define their own system of measurement. Generally, I keep my coordinate systems pretty big. Here's an example of the scale used for a Gears of War character. As you can see, their scale is quite big

[JP]

You can define whatever relation you want, decide on it with your artists and then they can use that relation when modelling. If you don't have artists and are using random models from the internets then you will undoubtedly have to do some scaling to get them all to the right scale if they've been made by different artists using different scales!

[Mel]

Want an example? Quake III defines 1 unit = 1 feet. Characters are 8 units tall, perhaps. But in these times, anything can be used.

[Jake-GR]

I havent jumped into using a physics engine yet, but ive heard most physics engines like having 1 unit = 1 meter (or possibly just multiples of 10)

Personally im going with 1:1 because it makes sense to me and a lot easier for me to work with distance calculations (ex. object is 104.8 units away, so throwing a laser range finder on a gun just spits out 104.8m no added calculations)

[B@z]

it is the matter how big are you making your models.
as for me, i make the first character, and making everything to its scale.

[Virion]

it is the matter how big are you making your models.
as for me, i make the first character, and making everything to its scale.

same

[Katsankat]

Want an example? Quake III defines 1 unit = 1 feet. Characters are 8 units tall, perhaps. But in these times, anything can be used.

For future readers, it is 1 unit = 1 inch, legacy from Doom. Player height is about 72 units in level editors as well as modelling programs.

[christianclavet]

I'm using exactly that. If you use 3DSMAX they have a GENERIC unit, that match that.

I've set 3DS to use that GENERIC unit and create boxes of 72 unit high to have a reference point for a character.

[Katsankat]

le mec ferait 1m83

[Mel]

Want an example? Quake III defines 1 unit = 1 feet. Characters are 8 units tall, perhaps. But in these times, anything can be used.

For future readers, it is 1 unit = 1 inch, legacy from Doom. Player height is about 72 units in level editors as well as modelling programs.

Duh! my bad, thanks for pointing that out ^^U

[koscianski]

I've got two problems related to scale.

(1/2)
Exporting from Blender: I thought "1 unit = 1 meter"; now, importing the mesh (a building) into Irrlicht, I have no idea about the scaling factor to apply. By applying scale = 10 it matches, more or less, "sidney.md2". I hope most models follow approximately the same size.

(2/2)
I got puzzled with the seventh tutorial. It says,
"We'll set it to (0, -10, 0), which approximates to realistic gravity, assuming that our units are metres. ... But as human beings, we are used to have our eyes on top of the body... So we place the scene node 50 units over the center of the ellipsoid"

Doesn't it mean that the eyes are 50 meters above the ellipsoid?!

(2+1/2)
Does the "AddNodeCube" thing (fourth tutorial) adds a cube of size one?
(and If not, why?!!)

[omar shaaban]

well 1 unit in irrlicht = 1 unit in blender or any 3d program.