So,
let's make some wheels, the rims consist
of 3 sections, an outer rim (which is
a lathed spline), bevel and inner rim
both of which were made from primitive
objects (a tube) - I could have done
it with one lathed spline but hey that
would have been easier and I felt this
method gave me more control over the
look of the finished article - I could
easily add a polished chrome section
if I wanted. The spokes were created
using a swept spline and the spinners
using hypernurbs starting with a 6sided
cylinder as the base primitive. No real
dramas here, after all they are only
round things with a few holes in them
and some bits that stick out.
The
tyres were not quite so "easy",
I understood the principle and I'd just
about got a handle on the technique
in C4D, create a single section of tread,
then using the duplicate function to
create a long flat object which you
apply a bend modifier to it in order
to create the whole tread.
Sounds
"easy" doesn't it? Well in
theory it is but what you must allow
for is the sheer amount of guesswork
and minor adjustments to scale, number
of copies, spacing etc involved in getting
it exactly right. No two tyres will
be the same (unless of course you use
the same tyre over and over again) so
giving specific numbers and dimensions
(if I'd even kept a record of them)
wouldn't really help that much
Time
for a bit of forward thinking here.
I knew I wanted to add raised lettering
to the tyres and I knew the method I
was going to use so I needed a "solid"
object for the sidewalls. They were
made by creating a spline to match the
profile then applying a lathe nurbs
object to create a tube that fit perfectly
inside the tread and matched with the
lip of the wheel rim. I then selected
two loops of faces around the object
and applied a bevel to create the raised
sections on the tyres sidewall. A quick
alignment of points on the inner face
and a symmetry object and the tyre walls
were complete
The
lettering on the sidewalls was done
with a little creative use of Boolean
intersection. Using the text tool, type
the lettering you want and then add
a sweep to it. You can now bend the
text to match the wheels diameter. Intersect
it with the sidewall then move it slightly
outwards - the result is raised lettering
that matches your tyres profile exactly
- neat and very effective in a lot of
situations where a texture map just
won't cut it.
I covered this method in a little more
depth with a tutorial over on Caligari's
website - although aimed at trueSpace
users it works effectively with any
software.
Having 4 nice shiny wheels (actually
at this stage it was just two shiny
wheels and a symmetry object to make
the other two) but they were looking
kind of lonely in the middle of the
scene. What they needed was some axles,
which in turn need sub frames, which
in turn need a chassis and so on.
The
rear sub frame and back axle are modelled
mainly from primitive objects. Based
on the Jaguar Independent rear suspension.
It's a big favourite with kit car builders
for it's sheer practicality and availability.
There's plenty of reference material
around for it and I used an exploded
diagram and my own working knowledge
of the system to get a reasonable representation.
Once again I only modelled half the
suspension and used the symmetry tool
to create the second half. When you
are creating complex objects like this
the "best way" I've found
is to work to a precise location on
the grid rather than trying to build
it to fit the model. This way you can
quickly line up components and if you
match the grid snap and movement units
to your model then everything just falls
into place. Not necessarily the "right
place" but at least all the components
are aligned perfectly and a bit of scaling
and tweaking will usually get the object
to fit pretty neatly. Any parts such
as shock absorbers that you need to
rotate to align try moving the objects
axis to the point where it will pivot
this will make your life a whole lot
easier than leaving the axis centred
and having to align both ends of the
object.
For
the front suspension I used a lot of
the parts from the rear and just re-sized
and repositioned them. Keeping the primitive
objects in their parametric state in
Cinema 4D makes this a lot easier although
there is a downside - I've noticed that
the more objects like this you'll pay
the price in terms of system performance.
It's not a huge loss in speed but in
complex scenes and when you have the
attention span of a flea it becomes
vitally important.
The
chassis was modelled from a design for
a "universal kit car" chassis,
which a friend is developing. A simple
ladder chassis and the sub frames are
bolted on to it. Don't fix (glue or
Boolean) any of the objects in place,
as you will probably need to move them
around a little to fit with your body
shell. You've now got a pretty solid
basis on which build the rest of the
car and dedicated enough of your "spare
time" and effort not to wish to
consign the whole project to that ever
increasing pile of "unfinished
projects" stored in some neglected
corner of your hard drive.
Building
the bodywork used pretty much standard
modelling techniques. Starting with
a polygon object and adding points then
bridging them. By using the symmetry
tool you only need to model one half
of the mesh and by arranging your object's
hierarchy so that the symmetry object
and your base object are children of
the hypernurbs object you can have a
completely smoothed mesh rather than
one with a visible seam running down
the middle
This
process for building cars is described
in detail in many tutorials for whatever
software you are using. At least reading
one or two of these would be considered
the "right way" and would
make the job relatively "easy".
Just to make life really difficult for
myself, I didn't bother and ironically
I found a really good one for Cinema
4D shortly after I finished modelling
the body shell. Car modelling really
isn't that hard and there is no great
mystery. It just requires patience.
Once
the overall shape was completed I cut
the apertures for the bonnet and boot
and doors using the split tool, again
with the bridge tool work around the
holes and the separated objects adding
points to give some depth
Once
they were all in place, I selected the
edge faces and did a flat bevel on them
to sharpen the edges. As this creates
a couple of triangulated faces you'll
need to either edit them out now which
would be the "right way" or
do as I did and wait until you've finished
the modelling then correct it in the
mesh once it's made editable which in
my opinion is the "best way".
A more honest appraisal of the situation
would be that I thought I'd get away
with it, as it wouldn't look too bad
in the final render "the best way."
As
many Cobras these days are replicas
the panels aren't always perfectly aligned.
To add a little realism I deliberately
made the bonnet "not quite fit"
by moving a couple of rows of points
slightly out of alignment with the bodywork
- maybe "slightly" over the
top but I felt it added to the realism.
The exhaust system was just a group
of circular splines swept along a path
to create the curves and bends. The
collector was built using SDS and caused
me more problems than the rest of the
exhaust system getting it to look just
right. The muffler is a capsule primitive
and the pipe itself was a tube swept
in the same way as the front pipes.
Moving onto the interior, the dashboard
was built using a group of splines.
To make sure it fit perfectly I made
a copy of the body shell and deleted
all the excess polygons leaving me with
just the surround of the passenger compartment.
Once I'd created the main spline I laid
it out flat in the workspace and positioned
the various instruments. Then made a
series of circle splines to create the
holes they would fit in connected them
to the main spline and applied a sweep.
The
steering wheel consists of two lathed
sections for the wood trim and a modified
and subdivided cylinder for the alloy
centre. The studs passing through the
wood are made using the Boolean intersect
method outlined earlier applied to a
cylinder then used in an array to position
the studs around the rim.
The
centre boss is an over complex bit of
modelling. I didn't need to go to this
detail but as I had no restrictions
on the polygon count I figured that
geometry would look much nicer in close
up renders than a texture map. Shown
below are the various components used
to make the badge (which was also used
for the bonnet badge and as the basis
for the owners club badge on the front
of the car)
The seats were just splines swept along
a path then subdivided with a little
point editing of the control mesh to
form the contour. The backs and sides
use the same method.
