Final Exam
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Avid Siman
Jun 21, 2025, 1:34:11 PMJun 21
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Due to the overwhelming popularity of my midterm exam posted a few years ago, I've decided to post the followup exam from that same course.
Below is the final exam given to my students in the XSI Advanced course I taught in 2004. The course was split between two main topics: Animation using the animation mixer, and rendering using mental ray. The midterm exam covered the former, while the final exam focused on the latter. The final exam was also half written, half practical. This is just the written portion of the exam. My students had an average score of 87 on this exam with the high score being a 98 (out of 100). Let's see how you do.
XSI v3.5 was current at the time the exam was given. Some features may behave differently than what you use today.
The exam is closed book. No notes. You are allowed a pencil and scratch paper. You have 60 minutes to complete the exam. The bonus questions do not count until all other questions have been answered.
==============================================================
Name:_______________________
June 1, 2004
Computer Animation II: Advanced Animation Techniques using Softimage|XSI
Final Exam, Spring 2004
Instructor: Matt Lind
Mondays: 2:00pm - 5:30pm
Instructions:
- Read all questions before beginning.
- Circle the letter that best represents the answer to each question.
- All questions MUST be answered in order to receive points on bonus questions.
PART I - True or False (1 point each)
1) A ray originating from a light source is a secondary ray.
T F
2) Only material shaders can call a light shader.
T F
3) The best way to optimize a raytrace renderer is to reduce the number of rays cast into the scene.
T F
4) Final Gathering is a method of image based rendering.
T F
5) An object's volume shader is only called if the surface is not 100% opaque.
T F
6) Raytracing begins after photon mapping has completed.
T F
7) A shadow ray is a secondary ray.
T F
8) Texture shaders are the only shader type that can be connected to any other type of shader in the render tree.
T F
9) Cutting the effector from a 2D chain in the schematic view has no effect on the chain's behavior when manipulated.
T F
10) Any 3D object can serve as an envelope deformer.
T F
11) If a property is displayed with italic typeface in the explorer it means it's referenced from somewhere else in the scene.
T F
12) Global ambience is a color value applied to every object in the scene at render time and is not physically accurate.
T F
13) An area light with 3 samples defined in U and V would be queried at a single intersection point by a shader the same number of times as 9 individual non-area lights.
T F
14) a UV sample on an object cannot be manipulated in 3D space.
T F
15) The word "Texel" is derived from "Texture Element".
T F
PART II - Multiple choice (2 points each)
1) A ray that leaves the camera, then exits the scene without hitting anything in between will call a:
a) material shader
b) output shader
c) environment shader
d) volume shader
2) An area light's sampling parameters are set to 3 in the U direction, and 4 in the V direction. How many times will the light be queried for illumination from each intersection point on an object's surface?
a) 1 time
b) 7 times
c) 12 times
d) none of the above
3) Another name for "caustics" is:
a) specular refraction
b) specular reflection
c) special refraction
d) special reflection
4) You're working on the next production of Count Dracula which contains a scene that takes place in the 'hall of mirrors' of an amusement park. The director puts you in charge of lighting and rendering the scene. While doing research on the story, you discover an important fact about vampires: they are not visible in mirrors (ie: they do not reflect). How do you pull off this effect using standard tools?
a) activate primary rays, de-activate secondary rays for the mirror(s).
b) activate primary rays, de-activate secondary rays for the vampire.
c) neither A or B.
d) both A and B.
5) The phenomena that occurs when the angle between an object's surface normal and scene camera is nearly equal to the angle between the object's surface normal and light source is called...
a) specular highlight
b) diffuse illumination
c) ambient occlusion
d) global illumination
6) A photon...
a) is a quantity of light energy
b) is transmitted only by lights
c) is emitted during the raytrace process
d) All of the above
7) To create the effect of water reflections on the bottom of a swimming pool, you would create a grid, apply a wave deformer operator to it, define a light, then activate:
a) caustics
b) global illumination
c) final gathering
d) All of the above
8) An example of an explicit texture projection is:
a) A bitmap of a label cylindrically projected onto a soup can
b) A bitmap UV wrapped onto an arbitrary surface
c) Both A and B
d) Neither A or B
9) What exactly does it mean for object(s) to be associated to a light "exclusively"?
a) Only object(s) associated to the light will query it for illumination.
b) Only object(s) associated to the light will ignore the light.
c) Only object(s) not associated to the light will ignore the light.
d) none of the above
10) When inverse kinematics are invoked on a 2D skeleton chain, what range of motion will the first joint (bone) use to solve the rotation angles of the chain?
a) 90 degrees
a) 180 degrees
b) 360 degrees
c) none of the above
11) Which axis of each bone points to the next joint in the chain?
a) local X axis
b) local Y axis
c) local Z axis
d) Varies depending on how the chain was drawn.
12) You're working on a TV production and are handed a character which has not been completely rigged because the person who created it had to leave suddenly to attend to family issues at home. You are now responsible for finishing the rig so the animators can begin working. While getting familiar with how it works, you select and translate the effector (wrist) of one of the character's arms and in the process of moving the effector cause the arm to flip (ie: the elbow swings around depending on the location of the wrist). What tool would you use to correct the problem?
a) up-vector constraint
b) direction constraint
c) set rotation keyframe on the bone that flips to lock it in place.
d) none of the above
13) A sphere's position is constrained to a cube. Where does the position constraint operator live in the scene?
a) on the sphere's operator stack.
b) on the sphere's kinematics property.
c) on the cube's operator stack.
d) on the cube's kinematics property.
14) You are lighting a complex scene containing many objects and involves heavy use of global illumination. After many hours, you are having problems getting one object in the middle of the scene to render to your liking. Its color and contrast appear correct, but too bright relative to its immediate neighbors. What would most likely remedy the problem?
a) adjust the radiance parameter on the object's material.
b) adjust the photon energy intensity of the light emitting the photons.
c) adjust the min/max sample radius and accuracy settings in the render options.
d) Use rendermap to record the object's illumination to a bitmap, then color
correct the resulting image before applying to the object.
15) A handy tool for character animation that automatically activates a scaling, rotation, or translate tool when an object is selected is called:
a) Geometry Approximation property
b) Transform property
c) an override
d) none of the above
16) When building character rigs, it's not uncommon for the wireframe to become very dense when all the controls and components have been put into place to make the character function. While powerful, complex rigs are often messy and difficult for the animator to discern details and be able to pick specific parts of the rig when needed. A tool that would make it easier for the animator to pick and choose the components needed is:
a) Geometry Approximation property
b) Shadow Icon Display property
c) Annotation property
d) none of the above
17) What does the Plot tool do?
a) Generates a NURBS curve where each control point represents the position of the
object on each frame.
b) Allows conversion of procedural motion (constraints, expressions, linked
parameters, ...) to explicit form (Fcurves) by recording the current value of
each marked parameter as a keyframe so the procedural operators can be
released/removed while preserving the original motion.
c) Create shape animation on an object that is deformed by deformation operators or
envelopes.
d) All of the above.
18) When working in the animation mixer, what's the difference between "merging" clips and "freezing" clips to a new source?
a) Freeze generates new Fcurve data from clips, Merge combines existing parameters while preserving keys.
b) Freeze plots animation from selected clips into a new clip, Merge combines clips only where they overlap in time.
c) Freeze plots animation from selected clips into a new clip, Merge combines only parameters common to both clips
d) none of the above.
PART III - Extra credit (1 point each)
1) Fill in the blanks (1 point each):
"Gee, Brain, what do you want to do tonight?"
"The same thing we do every night Pinky - Try to take over the _______!"
They're Pinky and the Brain, Pinky and the Brain
One is a genius, the other's _________.
They're laboratory mice, their genes have been _______
They're dinky, they're Pinky and the brain,
brain, brain, brain, brain
brain, brain, brain - Brain!
Before each night is ______, their plan will be ________
by the dawning of the sun, to take over the world
They're Pinky and the Brain, Yes - Pinky and the Brain
Their twilight campaign, is easy to _______
To prove their mousey worth, they'll overthrow the _________
They're dinky, they're Pinky and the brain
Brain, brain, brain, brain
brain, _______, brain - Brain (NARF!)
2) Who directed the very first episode of "Tom and Jerry"?
a) David Harmon, Rudolf Ising
b) William Hanna, Joseph Barberra
c) Chuck Jones, Friz Freleng
d) Tex Avery, Max Fleischer
3) What was the episode's title and what year did it debut in the theaters?
b) Tom and Jerry, 1927
a) Puss Gets the Boot, 1939
c) A Mouse in the House, 1946
d) (untitled) 1972
4) Who directed the next 113 episodes of the series while winning 8 academy awards? (hint: two people, one is still living).
a) David Harmon, Rudolf Ising
b) William Hanna, Joseph Barberra
c) Chuck Jones, Friz Freleng
d) Tex Avery, Max Fleischer
5) What groundbreaking project was undertaken by these directors after the 114th episode, and why was it groundbreaking?
a) The Flintstones, it was the first animated series based on a live action TV show (HoneyMooners)
b) Ruff n' Ready, it was the first animated series to be made on a small budget fit for TV production.
c) Magilla Gorilla, it was the first TV series based in a pet shop containing exotic animals.
d) One Hundred and One Dalmatians, it was the first animated film to use Xerography instead of manually painting ink lines on the cels.
6) Who continued the "Tom and Jerry" series after the 114th episode and nearly killed the franchise within the next 12?
a) Gene Deitch
b) John Halas
c) John Hubley
d) Ward Kimball
7) What other famous Animation Director picked up the reins and continued the "Tom and Jerry" series in the 1960's for another 33 episodes, yet admittedly didn't have a clue as to what the characters were about or what made "Tom and Jerry" successful?
a) George Plympton
b) Tex Avery
c) Chuck Jones
d) Walt Disney
8) What 2 other academy award winning (non-"Tom and Jerry") cartoons did this director create during that span in consecutive years?
a) The Line and the Dot / How the Grinch Stole Christmas
b) Rudolph the Red Nosed Reindeer / Rikki-Tivi-Tavi
c) The Lion, the Witch, and the Wardrobe / The Hobbit
d) Lady and the Tramp / 101 Dalmatians
9) Who said it: "I don't even know where the hell the cartoon studio is. The only thing I know is that we make Mickey Mouse!".
a) Walt Disney
b) Jack Warner
c) Leon Schlessinger
d) Max Fleischer
10) Where was Walt Disney born and in what year?
a) Oak Park, Illinois 1901
b) Kansas City, Missouri 1899
c) Lincoln, Nebraska 1910
d) White Plains, New York 1907
11) What was Walt Disney's middle name?
a) Elias
b) Aaron
c) David
d) Michael
12) Who created Bugs Bunny's catchphrase,"What's up, Doc?" and what was the inspiration for it?
a) Tex Avery, it was how everybody greeted each other at his high school.
b) Frank Tashlin, just liked the sound of the phrase.
c) Mel Blanc, it sounded funny when he said it while battling a cold one day.
d) Friz Freleng, saw it once on an episode of the Three Stooges.
13) What watershed moment occurred in 1950 that changed animation forever eventually leading to all Hollywood studios, but Disney, to close their theatrical animation departments by 1963?
a) The aftershock of the World War II and Korean War economies.
b) Animator's strike.
c) UPA studios winning the Academy Award for best picture on a shoestring budget.
d) Public Television.
14) Of the 600 cartoons produced at Warner Bros. animation studios from the 1920's thru it's closure in 1962, approximately how many of them still have existing original artwork for sale or display? (ie: cels, backgrounds, pencil tests, model sheets, etc..)
a) None, they were all buried when the studio closed in 1962
b) Three, and all are owned by the estate of the late Chuck Jones.
c) All 600, but have been sold in bits and pieces to various animation collectors.
d) All 600, with most kept safely in the Warner Bros vaults, others on display.
15) How many times did Disney studios go belly-up before finally finding the winning formula in the late 1920's with Oswald the Rabbit?
a) 1
b) 3
c) 9
d) 12
=============================
Matt Lind
animator / Technical Director
Softimage certified instructor:
Softimage|3D
Softimage|XSI
Matt...@mantom.net
XSI v3.5 was current at the time the exam was given. Some features may behave differently than what you use today.
The exam is closed book. No notes. You are allowed a pencil and scratch paper. You have 60 minutes to complete the exam. The bonus questions do not count until all other questions have been answered.
==============================================================
Name:_______________________
June 1, 2004
Computer Animation II: Advanced Animation Techniques using Softimage|XSI
Final Exam, Spring 2004
Instructor: Matt Lind
Mondays: 2:00pm - 5:30pm
Instructions:
- Read all questions before beginning.
- Circle the letter that best represents the answer to each question.
- All questions MUST be answered in order to receive points on bonus questions.
PART I - True or False (1 point each)
1) A ray originating from a light source is a secondary ray.
T F
2) Only material shaders can call a light shader.
T F
3) The best way to optimize a raytrace renderer is to reduce the number of rays cast into the scene.
T F
4) Final Gathering is a method of image based rendering.
T F
5) An object's volume shader is only called if the surface is not 100% opaque.
T F
6) Raytracing begins after photon mapping has completed.
T F
7) A shadow ray is a secondary ray.
T F
8) Texture shaders are the only shader type that can be connected to any other type of shader in the render tree.
T F
9) Cutting the effector from a 2D chain in the schematic view has no effect on the chain's behavior when manipulated.
T F
10) Any 3D object can serve as an envelope deformer.
T F
11) If a property is displayed with italic typeface in the explorer it means it's referenced from somewhere else in the scene.
T F
12) Global ambience is a color value applied to every object in the scene at render time and is not physically accurate.
T F
13) An area light with 3 samples defined in U and V would be queried at a single intersection point by a shader the same number of times as 9 individual non-area lights.
T F
14) a UV sample on an object cannot be manipulated in 3D space.
T F
15) The word "Texel" is derived from "Texture Element".
T F
PART II - Multiple choice (2 points each)
1) A ray that leaves the camera, then exits the scene without hitting anything in between will call a:
a) material shader
b) output shader
c) environment shader
d) volume shader
2) An area light's sampling parameters are set to 3 in the U direction, and 4 in the V direction. How many times will the light be queried for illumination from each intersection point on an object's surface?
a) 1 time
b) 7 times
c) 12 times
d) none of the above
3) Another name for "caustics" is:
a) specular refraction
b) specular reflection
c) special refraction
d) special reflection
4) You're working on the next production of Count Dracula which contains a scene that takes place in the 'hall of mirrors' of an amusement park. The director puts you in charge of lighting and rendering the scene. While doing research on the story, you discover an important fact about vampires: they are not visible in mirrors (ie: they do not reflect). How do you pull off this effect using standard tools?
a) activate primary rays, de-activate secondary rays for the mirror(s).
b) activate primary rays, de-activate secondary rays for the vampire.
c) neither A or B.
d) both A and B.
5) The phenomena that occurs when the angle between an object's surface normal and scene camera is nearly equal to the angle between the object's surface normal and light source is called...
a) specular highlight
b) diffuse illumination
c) ambient occlusion
d) global illumination
6) A photon...
a) is a quantity of light energy
b) is transmitted only by lights
c) is emitted during the raytrace process
d) All of the above
7) To create the effect of water reflections on the bottom of a swimming pool, you would create a grid, apply a wave deformer operator to it, define a light, then activate:
a) caustics
b) global illumination
c) final gathering
d) All of the above
8) An example of an explicit texture projection is:
a) A bitmap of a label cylindrically projected onto a soup can
b) A bitmap UV wrapped onto an arbitrary surface
c) Both A and B
d) Neither A or B
9) What exactly does it mean for object(s) to be associated to a light "exclusively"?
a) Only object(s) associated to the light will query it for illumination.
b) Only object(s) associated to the light will ignore the light.
c) Only object(s) not associated to the light will ignore the light.
d) none of the above
10) When inverse kinematics are invoked on a 2D skeleton chain, what range of motion will the first joint (bone) use to solve the rotation angles of the chain?
a) 90 degrees
a) 180 degrees
b) 360 degrees
c) none of the above
11) Which axis of each bone points to the next joint in the chain?
a) local X axis
b) local Y axis
c) local Z axis
d) Varies depending on how the chain was drawn.
12) You're working on a TV production and are handed a character which has not been completely rigged because the person who created it had to leave suddenly to attend to family issues at home. You are now responsible for finishing the rig so the animators can begin working. While getting familiar with how it works, you select and translate the effector (wrist) of one of the character's arms and in the process of moving the effector cause the arm to flip (ie: the elbow swings around depending on the location of the wrist). What tool would you use to correct the problem?
a) up-vector constraint
b) direction constraint
c) set rotation keyframe on the bone that flips to lock it in place.
d) none of the above
13) A sphere's position is constrained to a cube. Where does the position constraint operator live in the scene?
a) on the sphere's operator stack.
b) on the sphere's kinematics property.
c) on the cube's operator stack.
d) on the cube's kinematics property.
14) You are lighting a complex scene containing many objects and involves heavy use of global illumination. After many hours, you are having problems getting one object in the middle of the scene to render to your liking. Its color and contrast appear correct, but too bright relative to its immediate neighbors. What would most likely remedy the problem?
a) adjust the radiance parameter on the object's material.
b) adjust the photon energy intensity of the light emitting the photons.
c) adjust the min/max sample radius and accuracy settings in the render options.
d) Use rendermap to record the object's illumination to a bitmap, then color
correct the resulting image before applying to the object.
15) A handy tool for character animation that automatically activates a scaling, rotation, or translate tool when an object is selected is called:
a) Geometry Approximation property
b) Transform property
c) an override
d) none of the above
16) When building character rigs, it's not uncommon for the wireframe to become very dense when all the controls and components have been put into place to make the character function. While powerful, complex rigs are often messy and difficult for the animator to discern details and be able to pick specific parts of the rig when needed. A tool that would make it easier for the animator to pick and choose the components needed is:
a) Geometry Approximation property
b) Shadow Icon Display property
c) Annotation property
d) none of the above
17) What does the Plot tool do?
a) Generates a NURBS curve where each control point represents the position of the
object on each frame.
b) Allows conversion of procedural motion (constraints, expressions, linked
parameters, ...) to explicit form (Fcurves) by recording the current value of
each marked parameter as a keyframe so the procedural operators can be
released/removed while preserving the original motion.
c) Create shape animation on an object that is deformed by deformation operators or
envelopes.
d) All of the above.
18) When working in the animation mixer, what's the difference between "merging" clips and "freezing" clips to a new source?
a) Freeze generates new Fcurve data from clips, Merge combines existing parameters while preserving keys.
b) Freeze plots animation from selected clips into a new clip, Merge combines clips only where they overlap in time.
c) Freeze plots animation from selected clips into a new clip, Merge combines only parameters common to both clips
d) none of the above.
PART III - Extra credit (1 point each)
1) Fill in the blanks (1 point each):
"Gee, Brain, what do you want to do tonight?"
"The same thing we do every night Pinky - Try to take over the _______!"
They're Pinky and the Brain, Pinky and the Brain
One is a genius, the other's _________.
They're laboratory mice, their genes have been _______
They're dinky, they're Pinky and the brain,
brain, brain, brain, brain
brain, brain, brain - Brain!
Before each night is ______, their plan will be ________
by the dawning of the sun, to take over the world
They're Pinky and the Brain, Yes - Pinky and the Brain
Their twilight campaign, is easy to _______
To prove their mousey worth, they'll overthrow the _________
They're dinky, they're Pinky and the brain
Brain, brain, brain, brain
brain, _______, brain - Brain (NARF!)
2) Who directed the very first episode of "Tom and Jerry"?
a) David Harmon, Rudolf Ising
b) William Hanna, Joseph Barberra
c) Chuck Jones, Friz Freleng
d) Tex Avery, Max Fleischer
3) What was the episode's title and what year did it debut in the theaters?
b) Tom and Jerry, 1927
a) Puss Gets the Boot, 1939
c) A Mouse in the House, 1946
d) (untitled) 1972
4) Who directed the next 113 episodes of the series while winning 8 academy awards? (hint: two people, one is still living).
a) David Harmon, Rudolf Ising
b) William Hanna, Joseph Barberra
c) Chuck Jones, Friz Freleng
d) Tex Avery, Max Fleischer
5) What groundbreaking project was undertaken by these directors after the 114th episode, and why was it groundbreaking?
a) The Flintstones, it was the first animated series based on a live action TV show (HoneyMooners)
b) Ruff n' Ready, it was the first animated series to be made on a small budget fit for TV production.
c) Magilla Gorilla, it was the first TV series based in a pet shop containing exotic animals.
d) One Hundred and One Dalmatians, it was the first animated film to use Xerography instead of manually painting ink lines on the cels.
6) Who continued the "Tom and Jerry" series after the 114th episode and nearly killed the franchise within the next 12?
a) Gene Deitch
b) John Halas
c) John Hubley
d) Ward Kimball
7) What other famous Animation Director picked up the reins and continued the "Tom and Jerry" series in the 1960's for another 33 episodes, yet admittedly didn't have a clue as to what the characters were about or what made "Tom and Jerry" successful?
a) George Plympton
b) Tex Avery
c) Chuck Jones
d) Walt Disney
8) What 2 other academy award winning (non-"Tom and Jerry") cartoons did this director create during that span in consecutive years?
a) The Line and the Dot / How the Grinch Stole Christmas
b) Rudolph the Red Nosed Reindeer / Rikki-Tivi-Tavi
c) The Lion, the Witch, and the Wardrobe / The Hobbit
d) Lady and the Tramp / 101 Dalmatians
9) Who said it: "I don't even know where the hell the cartoon studio is. The only thing I know is that we make Mickey Mouse!".
a) Walt Disney
b) Jack Warner
c) Leon Schlessinger
d) Max Fleischer
10) Where was Walt Disney born and in what year?
a) Oak Park, Illinois 1901
b) Kansas City, Missouri 1899
c) Lincoln, Nebraska 1910
d) White Plains, New York 1907
11) What was Walt Disney's middle name?
a) Elias
b) Aaron
c) David
d) Michael
12) Who created Bugs Bunny's catchphrase,"What's up, Doc?" and what was the inspiration for it?
a) Tex Avery, it was how everybody greeted each other at his high school.
b) Frank Tashlin, just liked the sound of the phrase.
c) Mel Blanc, it sounded funny when he said it while battling a cold one day.
d) Friz Freleng, saw it once on an episode of the Three Stooges.
13) What watershed moment occurred in 1950 that changed animation forever eventually leading to all Hollywood studios, but Disney, to close their theatrical animation departments by 1963?
a) The aftershock of the World War II and Korean War economies.
b) Animator's strike.
c) UPA studios winning the Academy Award for best picture on a shoestring budget.
d) Public Television.
14) Of the 600 cartoons produced at Warner Bros. animation studios from the 1920's thru it's closure in 1962, approximately how many of them still have existing original artwork for sale or display? (ie: cels, backgrounds, pencil tests, model sheets, etc..)
a) None, they were all buried when the studio closed in 1962
b) Three, and all are owned by the estate of the late Chuck Jones.
c) All 600, but have been sold in bits and pieces to various animation collectors.
d) All 600, with most kept safely in the Warner Bros vaults, others on display.
15) How many times did Disney studios go belly-up before finally finding the winning formula in the late 1920's with Oswald the Rabbit?
a) 1
b) 3
c) 9
d) 12
=============================
Matt Lind
animator / Technical Director
Softimage certified instructor:
Softimage|3D
Softimage|XSI
Matt...@mantom.net
Sven Constable
Jun 22, 2025, 5:02:50 AMJun 22
to xsi_...@googlegroups.com
The question could have phrased like “How to achive that an objects is not reflected by another one…”, but instead you went far more creative, adding vampires and mirrors, haha! Very funny.
Sven
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Avid Siman
Jun 22, 2025, 10:33:40 PMJun 22
to xsi_...@googlegroups.com
And your answer is?
The goal of the question was to put the student in a real world scenario. Too often courses teach tools and theory but do not connect it to practice.
The goal of the question was to put the student in a real world scenario. Too often courses teach tools and theory but do not connect it to practice.
To view this discussion visit https://groups.google.com/d/msgid/xsi_list/000001dbe354%24697e3b40%243c7ab1c0%24%40imagefront.de.
Sven Constable
Jun 24, 2025, 5:56:02 AMJun 24
to xsi_...@googlegroups.com
Well, for this particular question the side story about a count dracula production and the object beeing a mirror, is important to the correct answer (c).
If the question would have phrased more bluntly like [obj-to-reflect] not to reflect on [reflective-obj], answer a) would not be entirely false. Or disputable at least. I like it.
To view this discussion visit https://groups.google.com/d/msgid/xsi_list/CAA6-QBuo7spGjpHL7PEXmJ81o4DCkH2HnM9M-pLH3dVU3UBA%3Dg%40mail.gmail.com.
Sven Constable
Jun 24, 2025, 3:22:52 PMJun 24
to xsi_...@googlegroups.com
We really could have shared questions for the students back then, Matt. :) The first or second year I worked for that school, we were asking the students for written answers. We switched to multiple choice on around 2002 or so. Easier to check but far more time consuming, creating all the answers.
Every answer had of course to be clearly right or clearly wrong and ideally, the wrong answers should also sound reasonable. I didn’t do bonus questions, but sometimes I add one questions at the end just for a good laugh (it didn’t count).
I don’t have the written exams anymore but one of the practical ones:
www.imagefront.de/tmp/tisch.mp4
(XSI, around 2004)
The goal was to recreate the lighting, texturing and animation within 2h. The model of the table/trampoline was provided and the dirt texture. As well as some scene specs (length, camera, 3 lights with shadow maps used). And the hint that a 2-joint chain was used for rigging. Focus lied on the animation.
Sven
To view this discussion visit https://groups.google.com/d/msgid/xsi_list/000701dbe4ee%242c3594e0%2484a0bea0%24%40imagefront.de.
Avid Siman
Jun 25, 2025, 12:19:03 AMJun 25
to xsi_...@googlegroups.com
Oooh, I'm sorry. That is incorrect. The answer is b) activate primary rays, de-activate secondary rays for the vampire.
The question effectively asks how to render the scene so everything reflects in the mirrors except for the vampire, but the vampire should still be visible when in direct view of the camera. The visibility of the vampire is determined by its render visibility settings. Primary rays determine whether the object is visible when in direct view of the camera. Secondary rays determine whether the object is visible to any other ray cast by a shader. In mental ray, a primary ray is any ray that emanates from the scene camera. A secondary ray is any ray that does not originate from the scene camera.
At the lowest level, a reflection is computed by shaders which cast a reflection ray into the scene along the reflection direction and see what it hits. mental ray follows the trajectory of the cast reflection ray and determines what it hits, if anything. Visibility settings are considered in the process. If the ray hits an object, but that object is marked as invisible, then mental ray ignores the object and continues along the ray path until another object is hit, or the ray leaves the scene. The information returned to the shader includes the object ID hit by the ray (0 if ray leaves the scene without hitting anything), the color information of the object at the ray intersection, surface normal, and a bunch of other metadata such as the ray depth counter, etc. To see a reflection rendered on a surface, the shader applied to the surface must compute the reflection and return the information to the camera. This proves a reflection is always a product of a secondary ray.
We want the vampire to be visible when in direct view of the camera, therefore we enable primary rays on the vampire.
We do not want the vampire to be visible in a mirror's reflection. Therefore we deactivate secondary rays on the vampire so shaders computing reflections do not see the vampire.
The answer cannot be a) activate primary rays, deactivate secondary rays for the mirror(s), because deactivating secondary rays would make the mirrors invisible in the reflections of the other mirrors.
The question effectively asks how to render the scene so everything reflects in the mirrors except for the vampire, but the vampire should still be visible when in direct view of the camera. The visibility of the vampire is determined by its render visibility settings. Primary rays determine whether the object is visible when in direct view of the camera. Secondary rays determine whether the object is visible to any other ray cast by a shader. In mental ray, a primary ray is any ray that emanates from the scene camera. A secondary ray is any ray that does not originate from the scene camera.
At the lowest level, a reflection is computed by shaders which cast a reflection ray into the scene along the reflection direction and see what it hits. mental ray follows the trajectory of the cast reflection ray and determines what it hits, if anything. Visibility settings are considered in the process. If the ray hits an object, but that object is marked as invisible, then mental ray ignores the object and continues along the ray path until another object is hit, or the ray leaves the scene. The information returned to the shader includes the object ID hit by the ray (0 if ray leaves the scene without hitting anything), the color information of the object at the ray intersection, surface normal, and a bunch of other metadata such as the ray depth counter, etc. To see a reflection rendered on a surface, the shader applied to the surface must compute the reflection and return the information to the camera. This proves a reflection is always a product of a secondary ray.
We want the vampire to be visible when in direct view of the camera, therefore we enable primary rays on the vampire.
We do not want the vampire to be visible in a mirror's reflection. Therefore we deactivate secondary rays on the vampire so shaders computing reflections do not see the vampire.
The answer cannot be a) activate primary rays, deactivate secondary rays for the mirror(s), because deactivating secondary rays would make the mirrors invisible in the reflections of the other mirrors.
The answer cannot be c) Neither A or B, because that would imply we don't have to do anything to create the effect beyond the default settings of the renderer, which we already know is false.
The answer cannot be d) Both A and B because deactivating secondary rays on the mirrors would make them invisible to each other.
The answer cannot be d) Both A and B because deactivating secondary rays on the mirrors would make them invisible to each other.
To view this discussion visit https://groups.google.com/d/msgid/xsi_list/000701dbe4ee%242c3594e0%2484a0bea0%24%40imagefront.de.
Avid Siman
Jun 25, 2025, 9:52:32 AMJun 25
to xsi_...@googlegroups.com
My practical was spread over 5 scenes across 2 groups. Students were instructed to pick 1 scene from each group, plus do the global illumination scene which everybody had to do. They had 2.5 hours available to do all the work.
The first group of scenes were for animation mixer concepts:
Scene A: Rigged biped man from the primitives menu standing with a ball above, and a table in front of him. On the table was a bowl with the same diameter as the ball. Task was to use the animation mixer to animate the man jumping up, grabbing the ball, then place the ball into the bowl on the table without any objects penetrating each other. It was a test of the student's ability to use poses and compensation such as offset maps.
Scene B: Aibo the dog from the netview examples database. Students had to use the animation mixer to seamlessly blend all the actions into a series of dog tricks. One gotcha was one of the actions had an invisible 360 degree rotation that would foul up the transitions. Students needed to know how to use compensation with offset maps and offset keys in order to solve the problem.
The second group of scenes tested the student's ability to use the animation mixer for animation:
Scene A: Cubic NURBS curve segments are drawn in an arbitrary shapes around the floor. Task is to animate a ball on the paths as if they were a single closed path, with proper amount of roll so the ball doesn't slide or skate. The ball's rotation should match it's direction of travel. A spotlight should track the ball as if it were a figure skater in the ice capades. This includes allowing a little lag between the ball's movements and the light's ability to track them. The purpose is to remind artists the goal is to imbue a human artistic quality to your work, not just settle for the technical solution which often looks cold and impersonal.
Scene B: A squadron of jets are flying in formation just like at an air show. The jets are flying along a curve which twists and turns, and the planes bank/turn appropriately. Problem is one of the jets is missing from formation. Task is to seamlessly introduce a new jet into the squadron and assume it's place in the formation without disrupting the other jets - and do so without animating the jet with keyframes (i.e. use constraints/expressions or other method, and blend using clips in the mixer).
The last scene everybody had to do. Variation of the Cornell box. A television is in one corner of the room, while a small table with glass figurines is located at the opposite corner of the room. A bowl of water sits between the TV and table with a wave deformation applied to induce water waves. Task is to render the scene using global illumination and caustics as well as setup the renderpasses to make assembly in the compositor efficient. Since it was an exam with strict time constraints, students only had to set up the scene, not render it.
The first group of scenes were for animation mixer concepts:
Scene A: Rigged biped man from the primitives menu standing with a ball above, and a table in front of him. On the table was a bowl with the same diameter as the ball. Task was to use the animation mixer to animate the man jumping up, grabbing the ball, then place the ball into the bowl on the table without any objects penetrating each other. It was a test of the student's ability to use poses and compensation such as offset maps.
Scene B: Aibo the dog from the netview examples database. Students had to use the animation mixer to seamlessly blend all the actions into a series of dog tricks. One gotcha was one of the actions had an invisible 360 degree rotation that would foul up the transitions. Students needed to know how to use compensation with offset maps and offset keys in order to solve the problem.
The second group of scenes tested the student's ability to use the animation mixer for animation:
Scene A: Cubic NURBS curve segments are drawn in an arbitrary shapes around the floor. Task is to animate a ball on the paths as if they were a single closed path, with proper amount of roll so the ball doesn't slide or skate. The ball's rotation should match it's direction of travel. A spotlight should track the ball as if it were a figure skater in the ice capades. This includes allowing a little lag between the ball's movements and the light's ability to track them. The purpose is to remind artists the goal is to imbue a human artistic quality to your work, not just settle for the technical solution which often looks cold and impersonal.
Scene B: A squadron of jets are flying in formation just like at an air show. The jets are flying along a curve which twists and turns, and the planes bank/turn appropriately. Problem is one of the jets is missing from formation. Task is to seamlessly introduce a new jet into the squadron and assume it's place in the formation without disrupting the other jets - and do so without animating the jet with keyframes (i.e. use constraints/expressions or other method, and blend using clips in the mixer).
The last scene everybody had to do. Variation of the Cornell box. A television is in one corner of the room, while a small table with glass figurines is located at the opposite corner of the room. A bowl of water sits between the TV and table with a wave deformation applied to induce water waves. Task is to render the scene using global illumination and caustics as well as setup the renderpasses to make assembly in the compositor efficient. Since it was an exam with strict time constraints, students only had to set up the scene, not render it.
To view this discussion visit https://groups.google.com/d/msgid/xsi_list/000001dbe53d%245c87c8d0%2415975a70%24%40imagefront.de.
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