[WALK-THROUGH] Fully Functional Vehicle (my first car).

[smokey13]

thanks for saying so

ok, so i fineshed the wheels today so i thought i would show the progress i have made.

lets start with the numbers.(the numbers i posted for the wheels yesterday wre for after i tried to lower the tri count)

so the original front wheels had 1250 verts and 2520 tris
the original rear wheels had 1500 verts and 3020 tris
so the original car had a total tri count of 32589

the new front wheels have 554 verts and 1104 tris
the new rear wheels have 458 verts and 912 tris
the new car has a total of 16983 tris

thats a total drop of 15606 tris

also i tried to scale the car but had some trouble, i will expalin. here is a picture to help show what i mean.

i figured the best thing to do would be to scale it 1/1 (1 blender unit=1cm) but did not know how big the driver would need to be.
so i decided to put a driver in the car, i measured my own bones then made a basic stick man using those measurments (as you can see in the pic, and just in case the head looks to big to you i thought it would be easier and save on the tri count to have a helmet instead of a face and measured a crash helmet i had lying around, it was 25 cm wide so made the head the same size). after i made the stick man i centered him in the car, then scaled the car up until it fit the driver because the drivers roughly the same size as me. the cars dimensions (in blender units) are 353 long, 232 wide, and 143 tall. just to put that into perspective a mk2 ford escort is 414cm long, 160cm wide, and 139cm tall witch means my car is pretty big but is as accurate as i can make it. there is a bonus though im going to keep a spare copy of the car with the stick man, that way when i try to make the driver i can model him in situe, witch means he will fit perfectly and i can get the various body parts (hands on the steering wheel for example) in the exact right place. then when i finish modelling him i can just delete the cars mesh and be left with a perfectly tailored driver.

i would appreciate your thoughts on this stuff

[geodav]

good so far, as for the scale of things you need to be careful with blender as a lot of the time when you import it into udk it will be matchbox size,

best thing to do is a quick size check, create a 64 unit box and export that, i show this problem or should i say how to set blender up scale/size wise in my videos.

btw i learned to drive in a escort mk2 estate

[smokey13]

youve got to love a mk2 escort

i just deleted the new front wheels and replaced them with slightly smaller versions of the new rear wheels witch has dropped the total cars tri count to 16599 witch means a total drop of 15990 tris. do you reckon that would be low enough, i could probably get rid of 400-500 more if i delete the spot lights and got rid of the wholes in the steering wheel if nesacery (looks kind of wierd without the spot lights though)

on to scale, here is a picture of the grid in the scene with my car (i leave it at the default sizes, i have seen your tutorial where you explain how to change it but i usually just use the properties window to check size)

as you can see the steering wheel is about twice the size of the grid (16 units) witch makes it about 32 units witch seems realistic, i did add a cube of 64x64x64 and it filled about 3/4 of the cocpit. here is a pic of the car with the properties window

i am pretty sure i scaled it properly. now i have 2 issues with scale, the first is the size in UDK because a few people say 1UU=2cm and other people say 1UU=1cm and im not sure wich one to use. the second issue was the size of the driver witch is why i thought making a roughly to scale stick man driver was a good idea.

so to sum up 3 questions
considering i plan on having a pretty low poly driver and am going to smoot shade most of it do you think a tri cout of 16599 is low enough?
did i apply scale properly? (im pretty sure i did as i did it the same way i scale static meshes and they look fine but better to sort it now rather then later)
witch size scale do you think would be best?

thanks

[geodav]

that will do nicely Sir

scale that looks good, once you've done the uvw's we can add a simple rig just to make sure the scale is what you need.

the scale i use i 1uu = 1 blender

ps we won't mention LOD's yet

[smokey13]

ok cool. i will drop the wheels a little bit and create a UV tomorrow. the car is already at a scale of 1UU = 1blender unit so thats all good, i have already centered the car but will do it again after i have dropped the wheels down, i will also delete the place holder driver but will create a spear copy of the blend file to do the driver at a later date.

as for LOD's erm yeah

[smokey13]

hi,

finally finished it (would have been yesterday but had a minor emergency on tuesday), anyway down to buisness. i have dropped the wheels slightly, unwrapped and layed out the UV (kind of a hatchet job though), created a basic texture (1024x1024 slightly bigger than i was going to use but i can always redo a smaller one at a later time), applied smoothing, and re-checked scale and model lacation in blender (scale is fine, model location is at 0,0,0).

i also did a test import to UDK, here is the result

as you can see the tris count is basicly the same (actually dropped by 20 tris) witch is good, and the buggy looks ok-ish, the only small problem i found was on the inside parts of the driveshafts (parts next to eginge) the normals were flipped witch is pretty easy to fix. i have not done a specular or normal map yet but will do them soon.

so what do you think, do you think it's good enough?

[geodav]

looks good to me, but i'm easy to please.

we need more vehicle stuff in UDK

[smokey13]

hi, i am trying to lay out the skeleton for my car (im not trying to assign vertex groups or set up the parent child relationship until i have the skeleton layed out), i wanted to start with the wheels but im having issues working out the correct position, in the tutorial it says i have to put the wheels bones exactly in the middle of the wheel (i get that it is so the wheel can rotate forward/backward and pivot it the middle for turning) but if you look at the picture

you can see a bone in the exact centre of the wheel witch will work for the forward/backward but it's supposed to turn with the wheel hub on the pivot point just below the point i highlighted so will i need another bone for that pivot point.

the wheel and wheel hub has to go up an down with the hub mount (dark grey bit) and im pretty sure i need a bone there as well.

i will need a bone at each end of the suspension but have no idea how to get the spring working.

the wishbone needs a bone where it attaches to the frame.

and probably the hardest part is the steering rack, the part coming out of the car has to push the connecting rod (witch also needs to rotate slightly), the connecting rod needs to push the wheel hub witch also turns the wheel and i have not got a clue of how to do it.(also the part of the steering rack poking out the side of the car is a solid bar witch also poke out of the other side in the exact opposite position and in turn pushes th other side of the steering rack turning the wheel in sync with this one).

so any advice/suggestions on bone position and how i would go about doing this would be extremely appreciated.

thanks in advance

[geodav]

now this is not going to be fun.
lots of hard work here to get the rig right and working in udk, in some places we have to think backward due to the way the vehicle code works, eg the wheels need to turn the hub, this means both bone ends need to have the same off set, we'll use skelcontrollers (look_at) to control the movement, basically where ever there is a pivot point we need a bone

don't forget the bone orientation X=forward Z=up this is very important as it will save problems later


leave the spring for the moment, i'll have to do a bit of research on that, i now its possible just i've forgotten how it was done

[smokey13]

experiments are allways fun

ok, i will put a bone on every pivot point except the suspension (i wont put bones in place for the steering rack/wheel or driveshafts for the moment either).

[smokey13]

and im back.

ok, so here is a pic of the rear bones ive placed so far (both sides bones are placed at the exact same points)
LR=left rear RF=right front.

the bones for the wheel, wishbones, and mid driveshaft are all placed on the pivot points. the inner driveshaft's bone is in the exact centre of the part (like the wheel but does'nt need to go up and down). i am not sure about the placement of the wheel hub and outer driveshaft bones, the wheel hub bone because it's not on an actual pivot point but it still needs to go up and down but obviously does not need to rotate and the outer driveshaft bone because the pivot point is technicaly right at the end of the driveshaft.

Q1: are the rear bones in the right places?

here is a pic of the front bones ive placed so far

the bones for the wheel, wheel hub and wishbone are in the pivot points, im not sure about the placement of the hub mount bone (at the moment it's in the centre but i think it should be at the outer pivot poit of the wish bone), correct me if i am wrong.

Q2: are the front bones in the right places?

i dont know where to place the steering racks bones, this pic shows it better.

the red circles are where i think bones should go but again i am not sure. i think one should go in the left red circle because that part needs to move left and right when turning. the other red circle i think needs one because it's a pivot point of the steering rod. the yellow circle i am not sure of at all (i was thinking of putting one there witch would rotate/move up and down in unison with the wheel hub and be a focus point for the "look at" skeletal control). that tube just above the left red circle is the steering column, it is joined to the steering wheel (as a linked sub object if you know what i mean), it needs a bone but i dont know where to place it.

Q3: am i right about the red circles?

Q4: am i right about the yellow circle?

Q5: where do i put the bone for the steering column/wheel?

turns out i can place quite a few bones alot quicker than i thought

EDIT- i oriented the bones exactly how you show in your tutorial so the bones axes is the same as the 3D veiw axes.

Q6: should i put bones at the top and bottom pivot points for suspension (not spring) or leave it for now?

Q7: does the rear wheel hub need two bones. one at the end of each wishbone?

[geodav]

your going to fast for me to keep up

q1. yep looks good, get rid of the rear outer drive shaft bone, you can assign those to the wheel bone
q2. front looks fine
q3. yes
q4. yes
q5. in the steering column
q6. put them in , they can be changed later if ness
q7. might have to do that

[smokey13]

your going to fast for me to keep up

im going to fast to keep up with myself(enjoying it though)

q1. consider it done, but should i move the end of the driveshaft down to lign up with the wheel? also what will the middle part of the driveshaft's bone be focused on?
q2. thats good
q3/4. ok, will add them
q5. should it be in the center of the whole "sub object" (column and wheel)?
q6. ok
q7. ok wiil do

[geodav]

q1. might be a good idea that, same for the wheel end of the drive shaft. the way i normally do things is that i move the wheel bones down after skinning/weighting but before exporting
q5. just line it up with the column

[smokey13]

ok, so i think i have now got most of my bones in the right places.

first just to double ckeck my cars front wheel hub mount bone heres a pic

the bone is centred it the middle of the hub mount (i highlighted it) but the pivot point between the wishbone and hub is where i put the red circle.

Q1. should i move it to the red circle?

now to the rear driveshaft

as you can see from the top pictures the end of the drive shaft goes through the hub and wheel witch is why i asked about moving the outer end driveshaft down to the same alignment of the wheel and have them use the same bone but then the middle part of the driveshaft would follow the middle of the wheel not the pivot point of the 2 driveshaft parts. i can only think of two ways to do it. the first would be to have 2 bones 1 for the wheel and one for the driveshaft (they would rotate together but the bone in the driveshaft would act as the foces point of the mid driveshaft bone). the second way would be to place 1 bone in the red circle (wheel and driveshaft end conneted to this bone), have that bone move up and down with the hub, it would also be in the perfect place for the focus point of the mid driveshaft bone.

Q2. witch one do you think would be better or do you know a different way?

if you think placing a single bone in the red circle for both the wheel and driveshaft to connect to would be best i would move the wheels back up to align with the driveshaft to place the bone in the exact right place, then use grid snapping to move the wheel and driveshaft down, then use grid snapping again to move the bone down the same amount as the wheel and driveshaft so it stays int the exact position needed.

Q3. whats the bone limit in the UDK? (because at the moment there are 39 bones, but i think i will also need 3 more to attach the driver)

i hope i wrote that in a way you could understand, im not good at explaining things