help-mirror/size shape/faces for bridging


#1

i have a problem with my modelling

3 models , from left to right , A, B, C
3 models that need bridging

model A , inserted shape , both have same number of verts etc , but are different shapes , i want to bridge them but a want the inserted shapes to be the same shape , i want the top inserted face to be the same as the bottom one - how is it done .

model B, 2 squares , both have inserted square faces , i want the top inverted face to be the same as the bottom one , so when they are bridged they are identical .

model C. i want the top models face to be identical to the bottom models face , here it is a square but it may be any shape , for example the same shape as model A , how do you make the highlighted faces the same

any ideas how i could do these operations , it would be a massive help to me,
thank you for your time
regards Dean Avanti project leader Altered State http://www.planetunreal.com/alteredstate


#2

Model1

select the bottom shape inset face

extrude>normal>0.0

do not deselect (spacebar or whatever you have keyed it to)

flatten (rightclick)>select inset face on top shape

do not deselect

hide bottom shape

select inset face on top shape

show bottom shape

bridge

There may be a faster way but that’s the first to come to mind… I’ll see what I can come up with on the others in a sec.

edit- Model 2, same technique

edit- Model 3, do you want the top shape to have a slope (like an upside-down pyramid)?


#3

Bottom objects seem to have the reference faces, so a similar procedure (for all 3) - for a general solution, where faces to be bridged aren’t necessarily parallel.

Select inset face on lower object
Extract normal a little (doesn’t matter how much) this face
Extrude normal a little (again doesn’t matter - just give it some thickness)
Use Face | PutOn to align this extracted extrusion to the underside face of the top object

Then, depending on exactly what you want to do - with the bridge op-

Adjust top inset face to new reference block (the thin extrusion)
See linked page for details (first section about making quads square) - cube used here, but (scale to point) technique will work with any shape.

Hide ref block and bridge.

pp

http://www.geocities.com/paulthepuzzles/aaassorted.html


#4

Originally posted by JDex
[B]Model1

select the bottom shape inset face

extrude>normal>0.0

do not deselect (spacebar or whatever you have keyed it to)

flatten (rightclick)>select inset face on top shape

do not deselect

hide bottom shape

select inset face on top shape

show bottom shape

bridge

[/B]

i just tried this , its a nice technique , but i notice that the two shapes are not joined , is there a way to join them , i want it to be one object , this keeps them as two objects , i cant see how i can join then together


what im trying to avoid is shown in these two examples

as can be seen by the two bridges here , the middle sections are not straight , if i was building steel girders they would look odd as the beams would not be parallel as the two faces where not the same size so one side is larger .

ill try puzzledpaul technique next after some sleep .


#5

Well, if you perform the last step… bridge, they should now be merged into one object. Doing this at angles (as shown in your response) may pose some other difficulties… I am at work now so I can’t look into it atm, but since you’re probably fast asleep, you are probably not in a major rush. I will see what I can come up with when I get home. :thumbsup:


#6

Ahhhhhh… the light is starting to glimmer :slight_smile:

What it seems you might be after is a way of joining 2 objects together (using bridge) with new geometry - that has a constant cross-section - irrespective of the angles of the end faces.

To use your analogy - using RSJs (girders) - these would have their ends trimmed to the appropriate angle, prior to being welded / bolted to the end anchor points.

If this is what you’re trying to do - you’ll probably have to employ a similar technique :slight_smile:

If you intend to try to do this on a general basis - to cope with end faces being at any (compound) angle - you are likely to have a fun-filled time :slight_smile:

pp

(First linked page shows a technique for true- ing up distortions in one plane)

www.geocities.com/paulthepuzzles/aascalecorrect.html

Using radial scale -> zero to align (previously irregular) edges might also be of interest.

www.geocities.com/paulthepuzzles/aaalign.html


#7

Hey Paul…

Can you shed a bit more light on the expression used in that scale correction tut.

What is Cosecant?

I don’t remeber this from trig (although I must admit, trig was not a focus of mine).

You know, I really think that this could be a plugin (perhaps called AngleTrim or something to that effect) that does the rotate and scale automatically… wish I was a coder.


#8

<< …shed a bit more light … >>

Cosecant - reciprocal of a sine in a rt angled triangle. (enter cosecant into google if want more info :slight_smile: )

I used it on my page as it looked neater (!) to have stuff multiplied, rather than divided (by sine of …blah de blah etc) - no great mystery or hidden agenda.

<< this could be a plugin >>

Mebbe - but a more useful tool - imo - would be a plane cut that has the facility to cut off at a compound angle (via tab box).

Plane cut (aka nendo) would see more general use than an ‘angle trim’ - and if it were possible to adust the cut plane in 3D space, this’d be the icing on the cake - all imo :slight_smile:

Since Bj has already indicated an intention re Plane Cut (and is aware of the general 3D issue) - I’m more than happy to leave it at that.

If just get XYZ plane cut (no 3D) - then user will just have to rotate element (to be cut / trimmed) onto the relevant plane - harly a problem.

re DA original problem - IF you want constant cross section geom - as I see it you’ve got 2 choices

Bridge across between the faces and adjust the (bridged) geom after to be what you need it to be.

Make a separate piece of geometry (of correct cross-section) line it up in the correct position, then join the 2 ends.

Both have their merits - but if you are intending to do lots of this sort of stuff - maybe the second - extruding new elements (girders) from reference cross sections, might be more useful?

pp


#9

Originally posted by JDex
Well, if you perform the last step… bridge, they should now be merged into one object. Doing this at angles (as shown in your response) may pose some other difficulties… I am at work now so I can’t look into it atm, but since you’re probably fast asleep, you are probably not in a major rush. I will see what I can come up with when I get home. :thumbsup:

i get this

see they are not joined as one , and you cannot connect via clicking the vertics and clicking connect , they are 2 objects that sit flush to each other .perhaps ive done it wrong ?

ive looked at puzzledpaul tuts , very good stuff , i reckon that can fix a lot of problems , im just looking at this from all the angles , i like to get to grips with wings as i often promote it to game modders who want tools to add game content , and you sure cant beat wings price and easy learning curve


#10

<< 2 objects that sit flush to each other >>

DA - just select the 2 flush faces and bridge - the bridge op will form new geom on the underside face of the upper object.

An easy way (imo) of selecting the (smaller, hidden) face is to select a vert on its periphery, press F, then de-select unwanted faces, leaving the required end face left selected.

pp


#11

thanks for the tips puzzledpaul ,
i think the easiest way to do it is following the tuts you gave previous .
i think the best technique to use on the bridging is the tutorial you did on technique for true- ing up distortions in one plane , i think this is the fastest way , im back from commitments so ill fire up wings and try it out on some game static meshes .


#12

i have just been through the tuts posted , while they answer the problems they suggest , but they seem very drawn out to a simple problem
see diagram

see letter b all the angles are correct , but look at face a , its different , the angle is not the same as b .i want it the same , you could drag it by hand , it would look ok to the eye but would not be perfect , there must be a quick answer , perhaps to know the angle of b and then just rotate a to same angle .
im amazed if there is not an easy answer because i am always joing beams to other sections , i would be amazed if wings did not have a feature for this problem , there must be a quick and easy solution to this that can be done very quickly , again and again for fast modelling .
this would be easier if you had a function that you selected one face , select anouther and bamm the second face is the same shape and size as the first , then bridge perfectly .
it seems it doesnt so the best you can do is correct what you have done , and by correcting the angle perhaps is the best bet ,
well you get what i mean , there must be a way to make 2 sides of you bridges shape the same ,
you could follow the tut on aascalecorrect but what a long way to do it sticking in seperate objects and then rotating and fiddling , it would take too long and would create more problems , it is best to bridge then alter the one face to alighn with the face you want .
i saw the tut on aaalign which works on the cylinder but i dont now how it can work on the shape above

i notice you can align to xyz , align to any other face would be a good option , boy that would be usefull , that solves the problem above also , a one click solution : )


#13

Imo this is not a ‘simple’ problem – with wings current toolset.

Whilst a modified approach similar to that outlined by JDex will cope with the relatively straightforward scenario shown in prob4.jpg – the same approach cannot really be used for non-trivial examples when the 2 end faces aren’t parallel.

<< to know the angle of b and then just rotate a to same angle >>

No – this won’t work, because if you rotate a (and keep its length constant), the top (anchor) face will become distorted. Using Flatten on this face – to regain flatness will introduce another (different) error, since the Flatten vector angle is different from that of the ‘bridge piece’.

It is also possible to use the scale radial -> 0% technique here, by defining the axis vector from one of the (correct) edges and anchoring its origin on one of the verts associated with the edge to be ‘adjusted’ – BUT – the end where movement / adjustment takes place will need adjustment in the same way as rotating it.

<< this would be easier if you had a function that you selected one face , select anouther and bamm the second face is the same shape and size as the first , then bridge perfectly >>

If the faces aren’t on parallel planes, then no – this also won’t work.
In this case the constancy of the true cross-sectional shape of the ‘bridging beam’ will be compromised. Having the same ‘shape’ on angled end objects will only guarantee a beam of constant cross-section under very particular circumstances.

Any adjustment to the faces at the ends of the ‘bridging beam’ MUST be made along vectors defined from the edges of beam (assuming it’s already correct and parallel) – otherwise you will introduce errors.

Applying vector moves – on the individual verts at the ends of the ‘beam’ – one at a time, using a beam edge for vector definition will accomplish this – but, unfortunately, it’s an ‘eyeball’ job :slight_smile:

(Switch into w/frame mode, Ortho, tumble model until a beam ‘end face’ becomes a single straight edge (side view) – then (vector) move end face verts until they lie on this line.)

There’s various approaches to all of this (although no ‘magic bullet’ – imo) - but it depends a lot on exactly what you want to do and the precise nature of the geometry you start with and that which you wish to create :slight_smile:

pp

<< i notice you can align to xyz , align to any other face would be a good option , boy that would be usefull , that solves the problem above also , a one click solution : ) >>

Highly unlikely - even if it did exist :slight_smile:


#14

i think its best to do it by hand ,and get it roughly were you want it .
the replies you give go straight over my head .
i think it is best to hand do as ther does not seem to be a quick option .
i don’t have the time to invest to learn every nuance of wings , the reason i use it is that i don’t have time to go over my vid tuts of Max and learn the program, and wings has a very shallow learning curve so fits into my time constraints, and game models that are under 2500 polys and simple static meshes don’t need complex modelling so one can get by in wings .
its all about time , if i got into more complex aspects of wings it is counter productive development time , i think if i was going to invest that amount of time it would be better done in Max if i was going to get into program complexities.


#15

:slight_smile:

If I get time over the weekend, I’ll put a strip together and add it to an existing page - and let you know.

(A general approach capable of dealing with any situation)

pp


#16

that would be great if you did , i am amazed someone hasn’t done a tut for it before , its an action i do all the time .
it would be a major help to me as a have a huge amount of static meshes to do for a mod for the ut2003k video game , like a couple of hundred meshes , they are simple models so they are not time consuming individually , but anything that helps my work flow is a real bonus .


#17

Hope this helps - bit of a rush, no magic bullets, bottom of linked page :slight_smile:

pp

www.geocities.com/paulthepuzzles/aabridgeweld.html


#18

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.