## (solved) Collision box definition

taikedz
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### (solved) Collision box definition

Hello

I am trying to find where collision_box is defined, and what its individual numbers represaent but cannot seem to see either in rubenwardy's guide nor on dev.minetest wiki any formal/detailed description....

Code: Select all
`collisionbox = {-0.5,-0.5,-0.5, 0.5,0.5,0.5},`

I tried changing them all to 1 or 2 on a test entity but the collision box remained the same.

What do the numbers mean...?
Last edited by taikedz on Sat Sep 10, 2016 17:03, edited 1 time in total.

qwertymine3
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### Re: Collision box definition

The numbers define the two corners of the box that the player collides with. These are relative the to center of the entity. The center of the entity is the position you get if you call get_pos().

Code: Select all
`collisionbox = { --[[first corner]] x,y,z, --[[second corner]] x,y,z}collisionbox = { x,y,z,x2,y2,z2}`

The sample you gave would produce a 1*1 meter collision box where the center of the entity is in the middle of the
collision box.

2D representations:
Code: Select all
`0.5|0.5+-----+|     | 0.5|  o  | -|     | 0.5+-----+`

Code: Select all
`+-----+ <(0.5,0.5)|     ||  o  |    o = center of entity|     |+-----+^(-0.5,-0.5)`
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taikedz
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### Re: Collision box definition

qwertymine3 wrote:The numbers define the two corners of the box that the player collides with. These are relative the to center of the entity. The center of the entity is the position you get if you call get_pos().

Great thanks - I am pretty sure the brief trials I did ddin't make a diference, but if your notes are indeed the case, then I should probably look harder!

EDIT -- it was due to a typo. Grr.

Cheers
Last edited by taikedz on Sun Sep 04, 2016 17:43, edited 2 times in total.

azekill_DIABLO
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### Re: Collision box definition

i encounter the same issue. i can't change the collision box. "collisionbox = {-0.2,-0.4,-0.2, 0.2,0.35,0.2}," still gives me a basic 1*1*1 box.
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azekill_DIABLO
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### Re: Collision box definition

oh sorry i found my error

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ulla
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### Re: (solved) Collision box definition

Hi where is the maximum collision_box dimension? example
Code: Select all
`collision_box = {            type = "fixed",           fixed = { -3.25,-0.5,-5.5, 3.25,-0.25,2.5  },        },`

for walkable node
I make a bridge door mod for build castle but max i can collide is 4x4 block? or is my error?

Krock
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### Re: (solved) Collision box definition

ulla wrote:I make a bridge door mod for build castle but max i can collide is 4x4 block? or is my error?

This is not your fault. Minetest does not support larger collision boxes because of performance reasons. Here's a reported glitch caused by a large collision box, and here the rejected pull request to fix this problem.

What you can do in this case is to register multiple nodes (or blocks, as you say them in-game) and limit them to a maximum of 3x3x3 meters span.
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v-rob
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### Re: (solved) Collision box definition

3x3x3 doesn't always work either. It's best just to register nodes and have them be placed next to each other like the homedecor mod usually does.

ulla
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### Re: (solved) Collision box definition

Krock wrote:
ulla wrote:I make a bridge door mod for build castle but max i can collide is 4x4 block? or is my error?

This is not your fault. Minetest does not support larger collision boxes because of performance reasons. Here's a reported glitch caused by a large collision box, and here the rejected pull request to fix this problem.

What you can do in this case is to register multiple nodes (or blocks, as you say them in-game) and limit them to a maximum of 3x3x3 meters span.

355/5000
Thanks for the reply, in fact I opted for 3x3, now I have to study swaps as nodes connected, considering that it is a bridge lift and makes 4 movements,
ps 3x3 works only if we start from the center, ie 1.5,0.25,1.5, -1,5,0,1,5 in my case and therefore the maximum possible collision extension for a cube is 1.5,1.5,1.5, -1.5, 0 , -1.5
Last edited by ulla on Sun Apr 08, 2018 14:15, edited 2 times in total.

ulla
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### Re: (solved) Collision box definition

v-rob wrote:3x3x3 doesn't always work either. It's best just to register nodes and have them be placed next to each other like the homedecor mod usually does.

thanks for the reply ps 3x3 works only if we start from the center,and therefore the maximum possible collision extension for a cube is 1.5,1.5,1.5, -1.5, 0 , -1.5 homedecor, has no objects larger than 3, it seems to me that the biggest is long sofa 3x1