Taking Inventor to the Max
Stephen Gabriel – MasterGraphics Inc.
About the Speaker:
Stephen began working with rendering software in its infancy in the early 1990s and changed to the 3ds Max
platform in 2001, giving him 20 years of experience from the advent of rendering on personal computers.
Stephen has spent the last ten years training, consulting and producing work in a variety of design and
visualization software packages from Autodesk encompassing both the manufacturing and architectural,
engineering and construction realms. Stephen has taught at Autodesk University and at AUGI CAD Camps in
addition to regular classroom training. Stephen holds a Bachelors degree in Architecture and is an Autodesk
Certified Instructor for 3ds Max. Currently, Stephen is the Technical Director at Studio MGI, a division of
MasterGraphics Inc., that is dedicated to production rendering and animation for manufacturing and architectural
visualization.
Taking Inventor to the Max
Introduction
Autodesk 3ds Max has long supported a streamlined workflow with Autodesk Inventor parts,
allowing you to quickly and efficiently brings parts and assemblies into the Autodesk 3ds Max,
apply materials and render out high quality images and animations. Like all software
integration, there are some aspects that warrant discussion and areas where a little
understanding and preparation can go a long way to easing the strain and time of the
conversion process.
The visualization process consists of 7 basic steps. Not every step is involved in every project
and they are not always done in the same order and many times, steps are repeated while
making adjustments in later steps. This class will cover a basic project involving visualization of
a ball valve.
1.
2.
3.
4.
5.
6.
7.
Storyboard
Modeling
Materials
Lighting
Animation
Rendering
Post-Processing
Step 1: Storyboard
The creation of a storyboard is one of the most important and most overlooked aspect of the
process. This is where you define what you need for output, whether it is a still image or an
animation and the level of detail and rendering quality. A good storyboard can range from a few
sentences to a simple diagram showing the camera position to a sequence of sketches. No
matter how you look at, defining your goals and sticking to them before you start working will
save you time and money.
Step 2: Modeling
More often than not, the model is already complete when it comes time to create visualizations.
As a result, this step is primarily focused on importing the model and adjusting it to work by
positioning it, organizing it or creating sections throught it.
Autodesk Inventor is a fantastic modeling package. It can do fillets and chamfers and drafts and
drilled and tapped holes and so much more. It produces parts and assemblies more easily and
more rapidly than Autodesk 3ds Max because that is its primary function while Max has many
more things that it must do. Model everything that you can inside of Inventor and apply
materials as you wish to see them in the final rendered object. This will save you a lot of time
and heartache when you import the model into Autodesk 3ds Max.
Scale and Rounding Errors
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Taking Inventor to the Max
Autodesk Inventor runs on double precision numbers while Autodesk 3ds Max runs on single
precision numbers. The result of this is that Autodesk 3ds Max can develop rounding errors
when the values are extremely large or extremely small. Round off errors result in distorted
geometry even though the geometry is properly defined. Two things can help in controlling this,
setting an appropriate scale and centering your model. Scale is set through the Units Setup in
the Customize top menu and it is important to consider the overall size of the model when
picking the scale. A cell phone with small buttons and detail would display poorly with the units
set to meters, but fine if the units were set to millimeters. On the other hand a 50 meter yacht
could have potential problems if the units are set to millimeters. Consider the size of the part or
assembly and set an appropriate scale before you import the model. The position of the model
within the scene can also affect the round off errors. Always try to center the model about the
origin of the file to reduce the risk of rounding errors at the edges of the model.
Import Process
Autodesk Inventor files are imported into Autodesk 3ds Max using the standard import
command which can be used to import part files (.ipt) and assembly files (.iam). Autodesk 3ds
Max Design 2011 and beyond include the Inventor Server which allows you to directly import
Inventor parts and assemblies without the need to have Inventor on the same machine. Before
you import the model, insure that all components are present as missing components will cause
Inventor Server to fail. If importing files from outside locations, have them use Pack and Go to
gather all parts together into a single file including parts from the Content Center.
There are a few things to be aware of with the import process:
•
All imported parts are brought in as editable mesh objects or Body Objects.
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Light settings and cameras are NOT imported.
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All constraints are lost.
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Starting with 2012 products, all materials will be imported as native Autodesk materials.
Prior to 2012, all materials will be imported as Architectural materials.
•
You can drag and drop Autodesk Inventor parts and assemblies into Autodesk 3ds Max
but Max will use the last version of Autodesk Inventor used for importing, not the version
associated with the file.
Import As - importing as a body object retains the objects original detail and accuracy while
allowing you to manipulate and modify the surfaces. Converting to a mesh creates polygonal
surfaces from the original model and makes for a lighter weight file. Regardless of the import
method, the model will be converted to mesh at render time.
Assembly Options - these options control the organization of the imported parts. Reference
Duplicate Parts creates instances for common parts. Create Layers by Material assigns all
objects with the same material to a layer. Add Object Name to Material will create a separate
material for each object which will cause a large number of duplicate materials to be created.
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Taking Inventor to the Max
Merge/Replace – select the option you want to either merge in the
data or completely replace the scene. In general, if you are going
to be importing multiple models of moderate complexity, it may be
easier and more efficient to import those in as separate files, reset
the materials and then merge them into a single scene file using
the Autodesk 3ds Max Merge command.
Material Options – With 2012 and beyond, you should Import
Inventor Materials as they are native Autodesk materials. Prior to
2012, you may wish to leave this checked to allow you to quickly
update materials on objects. There is no question on the Assign
Material IDs, you should always use this. Any part with multiple
materials applied to it will come in with material IDs preset for the
surfaces and the materials will be assembled as a multi/sub object
material.
Mesh Resolution – The Mesh resolution defaults to 0 every time
you start a new import and this is usually fine for most parts,
especially those with predominantly linear features. If all your
blocks are flat faced with straight edges, you can reduce this
without loss of detail, otherwise it is risky. Some complex curve
objects may need this value increased to provide acceptable
results. In this case, import those objects into a separate file at a
higher mesh resolution and then replace the lower mesh model in
the main scene file to avoid creating high res meshes on all of the
other objects in the scene. Increasing the quality setting a little can
have a profound impact on model import speed and file size.
Vertical Direction – Autodesk Inventor uses Y as its vertical axis. Autodesk 3ds Max and many
other 3d programs use Z. Leaving this at the default Y Axis
setting is recommended.
Grouping and Linking
Proper organization of the file is key to efficiently handling the
parts and assemblies within the scene. Many times, the
powers that be will request positional changes or operational
examples of assemblies to illustrate key design features. The
process of making these changes can be extremely tedious if
the model is not set up properly. Inside Autodesk Inventor,
you use constraints to establish relationships between parts
and sub-assemblies and then you drive these constraints to
position the individual parts and sub-assemblies into desired
positions. Unfortunately, these very useful constraints are
lost during the import process and must be recreated within
Autodesk 3ds Max. For simple position control, you can use
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Taking Inventor to the Max
groups and links to allow you to create the relationships between parts and sub-assemblies.
Groups
Grouping allows you to quickly grab a number of objects and create a shell entity
that contains the objects much like creating a sub-assembly inside of Inventor.
The advantage of a group is that you select the entire group whenever you select
any object within the group. The disadvantages are that you select the entire
group whenever you select any object within the group and you must open the
group in order to individually edit or translate any entity within the group.
Grouping is most efficiently used if the sub-assembly has not separately
moveable parts within it, such as with a pressure gauge or a complete assembly
to be merged into another scene.
The Group top menu contains a number of commands to help you create, undo
and manipulate groups.
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•
•
•
•
•
•
Group – creates a group from the currently
selected objects.
Ungroup – reduces the group to its next
level of objects.
Open – opens the group for editing, shows
magenta bounding box
Close – closes the group to end editing
Attach – attaches the currently selected item
to a group
Detach – removes the currently selected
item from a group
Explode – reduces the group and all nested
groups to the object level.
Linking
Linking allows you to create a parent child relationship between two objects. If the parent object
moves, the child moves along with it. If the child moves, it does not affect the parent. This is
extremely useful in setting up relationships that echo the constraints that you use in Autodesk
Inventor. The Motion tab of the Command Panel allows you to set up more advanced
constraints than can be covered in this course that can simplify the creation of simulations and
animations without the need to key frame every individual part motion in an assembly.
The Select and Link tool is used to create the parent child relationship. Start the tool by clicking
in the Main Toolbar, select your child object and drag and release while over the parent
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Taking Inventor to the Max
object. The parent object will flash when the link is established. Please note that this command
is perpetual, it will remain active until another command is started, such as a transform or select
tool. Objects that are linked will display in the Select in Scene dialog box in an indented
hierarchy when Show Children is selected in the Display top menu of the dialog.
Pivot Points
The pivot point of an object determines its center for all
translation commands, Move, Rotate and Scale. The pivot
point information is inherited from Inventor though it may
not be where you think it should be and more importantly
where you want it to be. The pivot point is associated with
the origin of the part file. In the example of this file, the
part was created in an assembly so the pivot point of the
part is at the origin for the assembly,
not necessarily where you would want
it to be.
In Autodesk 3ds Max, you can move the pivot point to a more logical
location. In the case of this part, it would likely be the sealing face of the
valve end rather than the journal face or the center of the valve. The
Hierarchy tab of the Command Panel contains the Affect Pivot Only button
which allows you to relocate the pivot point for an object. It is very
important to do this before linking an object to avoid unpleasant and unpredictable results when
translating linked parts.
Modifying the Model
Adjusting positions of objects within the scene are relatively easy
once you’ve decided how to organize the model and set up the groups
and links. The fun can really begin when someone asks you to take a
section cut through the model to expose the insides. The first tool you
reach for in here Boolean or better yet, ProBoolean. You create a
box, line it up where you want to cut, select your object, click on
ProBoolean under Compound Objects, click Start Picking and pick
your box and voila, your entire part disappears! What?!?
Parts and assemblies imported from Autodesk Inventor come in as
Editable Mesh objects with each surface broken out as its own
element. Each curve and straight segment from the original part
sketch yields a separate element. Add in the additional elements for
various features like holes, chamfers and fillets and a single part can
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Taking Inventor to the Max
be composed of many separate elements. And these elements just
do not get along well with either Boolean or ProBoolean. ProBoolean
tends to result in most of the part disappearing while Boolean leaves
holes, gaps and other artifacts. Neither situation results in a truly
useable part.
Two ways of overcoming this are welding the part into a single entity
and using the slice tool.
Weld and Boolean
Welding vertices combines all of the elements into a single object
that can frequently produce better results using ProBoolean.
Please note the “can”. The first thing to do is convert the object
into an Editable Poly object. Editable Poly objects have more
controls inherent within them that can help us produce better
parts in the long run. Welding the vertices will not affect the
material IDs on the individual faces. Try to weld all vertices for a
given part at the same time, this can prevent some unusual things
from happening on highly complex parts. It is very important
during the weld process that you set the Weld Threshold to a very
low value or you will have multiple adjacent points welding rather
than just coincident points which will cause distortions in your
surface. Try setting it around .001” which usually displays as 0’0”
but produces a clean model with quite a reduction in vertices.
Weee! Free scene file size reduction! Click OK and your model is
welded. Your part is now a single entity and it also looks like garbage. Why? It is actually a
rather simple issue, the welding causes issues with the smoothing groups. To correct this scroll
down the Polygon: Smoothing Groups rollout in the Modify tab of the Command Panel and click
to clear all of the existing smoothing groups followed by
to automatically apply
new smoothing groups based on the currently set smoothing angle. Depending on your model,
you may need to adjust the smoothing angle and repeat the clear and auto smooth steps.
Slice
The slice tool is available under the Edit Geometry rollout of the Modify tab for both Editable
Mesh and Editable Poly objects and works in a similar fashion for both.
In both cases, you must be in a sub-object selection mode with the
areas to be sliced selected. For best results, you should still weld all
the vertices to combine the object into a single element.
To use the slice tool, you first need to turn on the Slice Plane which
makes the position of the slice visible. Make sure to check the box for
Split, this creates two edges instead of a single edge, allowing you to
separate the two sides of the operation. You can move and rotate this
plane as desired to get your slice in the right direction.
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Taking Inventor to the Max
Once the plane is positioned, you can click
along the slice plane.
to split the object
If you are working with an Editable Poly object,
you can instead use
to eliminate the
need of having to orient the slice plane.
Quickslice allows you to specify multiple points
for the operation.
One of the nice features of using slice is that it retains both parts of the geometry to allow you to
do transitions from whole to sectioned views. Neither slice nor quick slice will heal the open
surface created by the operation. In this case the Editable Poly really shines because we can
use the Border sub-object selection method to select an entire opening in one click and
to close it up neatly.
The obvious question is why would you use a slice tool rather than a ProBoolean? Sometimes,
even after welding vertices, the ProBoolean and Boolean tools just don’t return a good part.
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Taking Inventor to the Max
Step 3: Materials
Once the modeling is complete, it is on to
handling the materials for the assembly. If
you checked the box to import the Autodesk
Inventor materials, then they are already
present including multi/sub-object materials
for those parts with multiple materials
applied to various surfaces.
Opening the Material/Map browser and
selecting the Scene Materials rollout reveals
a common issue with importing from
Inventor, there are multiple identical
materials assigned to duplicate parts. This
can create some difficulty when working in
very large assemblies with thousands of
parts and therefore thousands of materials.
Reducing Material Count
With 2009 and prior versions, you had
several choices on how to handle this. You
could load the materials into the Material Editor, select objects by material and assign a single
material to objects with similar materials. This was long, tedious and boring. You could instead
create new materials and then select objects in the scene and apply the material. This was also
long, tedious and boring.
In 2010, Autodesk introduced the Material Explorer and this helps us resolve the issue more
effectively. In the Material Explorer, we can select a group of materials using the Find box and
use Select Children under the Select top menu to select all objects in the scene with the given
material and replace it quickly. The Material Explorer provides for a faster and easier cleanup of
the multitude of materials.
Material Types
Once the materials are reduced to a tolerable amount, it is time to start adjusting materials to
get the desired appearance. All Autodesk software packages have standardized on the mental
ray rendering engine which is capable of very high quality results. Starting with 2012 products,
all Autodesk software is also now standardized on the Autodesk Material which was designed to
work specifically with mental ray and provides a common material set across all applications.
The Autodesk Material is a good initial material type and is easily adjusted for certain
parameters however it does take longer to render and is not as flexible as the Arch & Design
material type native to Autodesk 3ds Max.
The Arch & Design material was developed by mental images specifically for hard surface
visualization work and it is a more flexible material type. The Arch & Design materials come
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Taking Inventor to the Max
with templates that provide an excellent starting point for
building most materials and can be quickly adjusted to
replicate most material surfaces.
The Autodesk Materials are organized by type and have
fewer adjustments than Arch & Design materials. While
this makes them quicker to set up for novice users, they
lack the flexibility and power desired by advanced users
and they also take considerably longer to render.
Many times, an object will have different materials applied
across different surfaces. The Multi/Sub-object material
allows you to load multiple materials into various slots that
correspond to material IDs on the surface when an object
requires multiple materials based on the surfaces.
The Matte/Shadow/Reflection material allows you to
create a surface that will accept and cast shadows and
reflections without rendering. This is an ideal material for
capturing shadows and reflections for compositing onto a
surface.
Important Surface Qualities
It is important to understand how we perceive surfaces in order to create believable rendering
materials. Nearly all of the surfaces used in manufacturing can be approximated by
emphasizing four separate features: Diffuse Color, Reflection, Refraction and Bumps. The
diffuse color can be represented by a solid color or a map, either bitmap or procedural, and
defines the surface color under direct lighting. Reflections and refractions determine how much
light bounces off or penetrates through a surface. Both of these also have a glossiness, a value
that determines the coherency of the reflected or refracted light. The bump determines the
small surface textured, such as the mortar lines in a brick wall, that add detail to the surface
without adding to the model.
Learning to define real world materials by these four main areas will help you simulate the
materials while rendering.
Common Surfaces
There are a number of common surfaces that are regularly encountered in manufacturing
visualization and most of these can be quickly obtained through the use of Arch & Design
Templates with occasional quick maps attached.
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As-Cast Surfaces
The fastest way to create an as-cast surface is through
the use of a default Arch & Design material with the
Diffuse color slot set to the paint color for the surface
and the Reflectivity adjusted based on the glossiness
of the paint. The as-cast surface marks can be created
using a cellular map set to Circular with Fractal
checked and Thresholds of .4 for Low and .7 for high.
The Size and Spread will need to be adjusted based on
the casting method and part size but this produces a
useable and believable as-cast surface.
Tool Marks
Tool marks are essential in establishing believability
of machined surfaces since rarely are any of them
mirror smooth or highly polished. The basic Arch &
Design material using the Brushed Metal template
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Taking Inventor to the Max
provides an exceptional starting point. Frequently the only change required is to change the
color value of the Color #1 or Color #2 in the Noise Parameters rollout of the Reflection Color
slot. It is important to adjust the UVW mapping for tool marks, especially on turned surfaces.
Threads
Autodesk Inventor provides a preset thread bump pattern, unfortunately, it doesn’t come through
in the import process. The use of a gradient pattern from a bitmap editor can provide you with
very nice threads. Apply the map in the Bump slot and set the strength high. In the case of
threads, it is frequently easier to not use Real World Map Scale, apply a UVW Map and set the
thread count using the Height field. It is common to not scale the threads accurately, instead
make them large enough to be visible but small enough to be believable. If the end viewer
cannot perceive the threads then the illusion of reality is lost.
Background Switcher
The background switcher is a map that can be used to allow a surface to receive light from the
environment but switch the ray trace reflections to a specified image, allowing you to render in
one environment while showing reflections of another.
Multi/Sub-Object
The Multi/Sub-Object material provides multiple slots for materials allowing you to apply a
multiple materials to a single object with the materials sorting out by the material ID assigned to
each element, polygon or face of the object.
Step 4: Lighting
All scenes are created with default lights but they have poor control and limited quality.
Autodesk 3ds Max Design supports the use of Photometric lights, light sources that behave like
real world lights which makes them more predictable and easier to use. Lighting itself is broken
into two distinct areas: Direct Illumination and Indirect Illumination. Direct illumination is the light
that strikes the object and bounces straight to the camera. Indirect illumination is light that
bounces off one or more surfaces before striking the final object and traveling to the camera.
Indirect illumination provides light in shadowed and occluded areas. It is important to calculate
both forms of illumination in order to properly light a scene.
Target Lights and Free Lights
Lights can be added as target lights or free lights. Target lights point at a specific point or target
while free lights point into the view they were created in and a light can be switched back and
forth between the types. Lights emit energy in one of four patterns and
have parameters for their brightness, color, shadows and shape.
Lights can be set to emit energy as Photometric Web, Spotlight,
Uniform Diffuse and Uniform Spherical. A Photometric Web light uses
and IES file to emit light in a pattern determined by the manufacturer.
A Spotlight emits light in an adjustable cone shaped pattern. A Uniform Diffuse light emits light
in parallel rays from a set shape and area. A Uniform Spherical emits light from a point in all
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Taking Inventor to the Max
directions. Uniform Diffuse lights are excellent at simulating the light boxes and reflectors
commonly used by photographers.
The brightness of a light is controlled by its Intensity and can be adjusted using lumens, candela
or lux at a set distance. the selection of a preset bulb type will set both Intensity and the color
temperature of the light.
While there are a number of shadow types available, the features of
Photometric lights are most effective when using Ray Traced Shadows
and by setting a shape and size under the Shape/Area Shadows
rollout. This will produce high quality shadows with a pronounced
penumbra, avoiding the appearance of harsh shadow lines that readily
identify CG images.
Lighting Techniques
The three point lighting technique uses a primary light to one side, a fill light to the opposite side
and a rim light behind the object. This is a standard lighting techniques used by photographers
and motion picture artists and is easily set up. The primary light should always have its
shadows enabled while the fill and rim lights frequently do not have them enabled. This
improves appearance by not having multiple shadows in the shot as well as reducing rendering
times by not having to calculate shadows. In some instances, such as with a white room
appearance, the rim light is unnecessary and undesired as it will bleed out the back edge of the
object into the background. In either case, Final Gather is used to generate indirect illumination.
Exposure Control
Autodesk 3ds Max uses real world lighting
and a real world camera and just as in the
real world, you will need to control the
exposure of the image to obtain optimal
results. It is best to use mr Photographic
Exposure Control when rendering with
photometric lights and mental ray. This
comes with convenient presets as well as
the ability to render a preview and adjust the exposure control to get acceptable results without
the need to render a full sized image.
Step 5: Animation
Animation in Autodesk 3ds Max is controlled through the use of key frames that allow you to
store information regarding an objects position, rotation scale or many other parameters at a set
point in time. The software then interpolates the transition from one keyframe to the next using
function curves to control the rate of change. This is the same process used to generate
animated films and cartoons only the computer does the tweening rather than an artist.
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Keys
Animation keys can be placed using Auto Key or Set Key. Auto key
automatically places a key at the current time when it detects a change
to any parameter that it is set to record. Set key places a key only
when the user requests it. The information stored by both methods is
determined by the Key Filters and the keys will use the currently
selected curve type. This type of animation allows the user to
concentrate on setting up the initial animation and then go back into
the mini-curve editor and fine tune the animation later on.
Time
Animations are created with a set playback speed recorded as frames per second (fps). The
speed should be determined during storyboarding and it has a large impact on the time required
to render an animation. Computers typically use 30 fps while NTSB is technically shot at 29.97
fps. Motion pictures use 24 fps, which is usually sufficient for most animations. The higher the
frame rate, the smoother the animation and the longer it takes to render.
The Time Configuration dialog also allows you to adjust the overall
length of the animation by either entering a new number for the end
frame or by using Re-Scale Time to scale all keys to the new
animation length.
Editing Curves
The use of curves allows you to adjust the rate of change between
two keys with each key supporting an In Curve and an Out Curve.
The Mini-Curve Editor is a convenient way to edit individual curves and in some instances is
easier to use when creating keys for the primary animation. Curves can be easily changed and
the time and value of a key edited inside the editor making this an ideal way to fine tune an
animation.
Step 6: Rendering
Rendering is commonly seen as the final step in the visualization workflow and it is the point at
which the user submits the scene and then sits back and waits and hopes everything looks right
when it finishes. There are three general areas of concern in rendering that will affect both
rendering quality and rendering time. In general, if the setting increases the quality, it will
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increase the rendering time and the trick is to find a balance between both quality and time that
allows you to complete the rendering at an acceptable level of quality in the time frame required.
Indirect Illumination
Indirect illumination is often handled solely with the Final
Gather controls in the Render Setup dialog. The Final
Gather pass is executed before the final beauty pass and
it is processed in buckets displayed as square areas in
the rendered frame window. Increasing the Initial FG
Point Density will decrease the size of the square and
increase the accuracy of the solution while increasing the
time. Increasing the Rays per FG Point will improve the
samples and result in a better image, also at the cost of
time. Increasing the Diffuse Bounces will spread the light
around the scene better, increasing brightness in area
without direct illumination while increasing rendering
time. Balancing the three of these will lead to an even
and well lit scene while controlling the rendering time.
For larger images, the FG solution can be pre-generated
and saved at one half the final resolution and then read
from file during the final rendering. This reduces the time
for the final gather pass as well as freeing up system
resources during the final beauty pass.
Image (Sequence) Size
The size of the rendered image is controlled through
the Common tab of the Render Setup dialog which
provides access to common formats as well as the
ability to set custom sizes. Image size has a
dramatic impact on the rendering time with doubling
the image size increasing the rendering time by
about 4 times. The Common tab also contains the
controls for rendering a set of animated frames. The
Common tab allows you to automatically save the
image upon completion of the rendering. This is key
when doing animations where you will render and
save individual frames on one or multiple computers.
Checking the box for Net Render allows you to
utilize multiple computers to render an animated
sequence and can allow you to render animations in
a reasonable amount of time.
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Image Quality
The Renderer tab controls the anti-aliasing of the image
as well as renderer specific parameters like ray trace
bounces. Anti-aliasing, the removal of jagged lines, is
controlled through the Sampling Quality rollout of the
Renderer tab. The Samples per Pixel allows you to set
the minimum and maximum number of samples. The
default is minimum of 1/4 and maximum of 4 which is
good for most preview renderings. The Filter Type
allows you to set how the software will determine if a
pixel needs to be adjusted. The default is Box which is
quick but not very effective and is often used during test
renders. Mitchell and Lanczos are commonly used in
final renders. The Spatial Contrast settings allow you to
control the sensitivity of the sampling with the defaults
set to 0.051, which represents a 5% difference in color.
Lowering these values will increase effective range of
the sampling and produce a higher quality image.
Increasing any of these settings will increase the
rendering time, sometimes considerably.
The Rendering Algorithms rollout contains the settings for Ray Trace Reflections/Refractions.
These settings determine how many times light will reflect off of or transmit through surfaces
before it stops calculating that specific ray. The Maximum Trace Depth is the combination of
both Reflections and Refractions. In general, the default values work well but you may need to
increase the Refractions if you are using transparent materials and begin to notice black spots.
Reducing these values may decrease rendering times while increasing them usually does
increase rendering time though it is highly dependent on the geometry and materials in the
scene.
Step 7: Post-Processing
Post-processing includes adjusting exposure, contrast, brightness, color and compositing,
compiling and editing of animated clips. These operations are usually handled in software
outside of Autodesk 3ds Max.
Summary
The generation of quality rendered still images and animations from Inventor models can be
easily and quickly achieved using Autodesk 3ds Max. 3ds Max can directly import the model
and retains naming conventions and material assignments allowing for easier handling and
adjustment of the file. The use of real world lighting systems allows for faster and more
predictable lighting and the animation tools allow you to bring your models to life.
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