intoduction to blender

7/29/2019 Intoduction to Blender

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T4 Bacteriophage Project: An

Introduction to Blender

Iwan KartikoDept. of Computing, Macquarie University


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Hardware Requirements1

Supported Operating Systems

Windows (2000, XP or Vista), Mac OS X 10.2 and later, Linux 2.2.5 i386, Linux2.3.2 PPC, FreeBSD 6.2 i386, Irix 6.5 mips3, and Solaris 2.8 sparc

Minimal specs for Hardware

300 MHz CPU

128 Mb RAM

20 Mb free hard disk Space

1024 x 768 px display with 16 bit colour

A three-buttons mouse

Open GL graphics card with 16 Mb RAM

Good specs for Hardware

2 GHz dual CPU

2 Gb RAM

1920 x 1200 px display with 24 bit colour

A three-buttons mouse

Open GL graphics card with 128 or 256 Mb RAM

Production specs for Hardware

64 bits, Quad core CPU

8 Gb RAM

2 x 1920 x 1200 px display with 24 bit colour

A three-buttons mouse and a tablet

Open GL graphics card with 768 Mb RAM, ATI FireGL or NVIDIA Quadro

1Taken from http://www.blender.org/features-gallery/requirements/ Last accessed in February 2010.

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Software Requirements

Python 2.6.4

Website: www.python.org

Python is a popular programming language. We will not do any python programming inthis book. However, Blender requires a copy of Phyton installed to run certain scripts.

Blender 2.49b

Website: http://www.blender.org/download/get-blender/

Blender is a free and open-source application that can be used to create 3D models,animations, real-time content, and compositing. The latest version of Blender at thewriting of this manual is 2.49b. The latest development version is 2.50 alpha1, whichis not suitable for production setting. Blender 2.50 is the development branch towardBlender 2.6x and has many changes from Blender 2.49b. However, the method given inthis book can be applied when Blender 2.60 is released.

T4_Bacteriophage_Project.zip

This file contains Blender files that are used in the production of this manual. TheseBlender files are provided to accompany this manual as worked examples to assist learn-ing. Most importantly, this file contains the sketch file, which is needed in Chapter 3.

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Contents

1 Introduction 11

2 Blender 13

2.1 User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132.2 Setting up Blender for first time use . . . . . . . . . . . . . . . . . . . . . 142.3 Hotkeys and simple exercises of Blender . . . . . . . . . . . . . . . . . . . 16

2.3.1 Exercise 1. Orientation in 3D space, selecting and creating object. 16

2.3.2 Exercise 2. Transformations, deleting and creating primitives. . . . 192.3.3 Exercise 3. More on transformations and object selection. . . . . . 192.3.4 Exercise 4. Object editing, selecting and transformations. . . . . . 202.3.5 Exercise 5. More on object editing. . . . . . . . . . . . . . . . . . . 21

3 3D Modelling 23

3.1 Scene Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233.2 Modelling the shape of T4 Bacteriophage . . . . . . . . . . . . . . . . . . 253.3 Modelling the background . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

4 Rigging 39

4.1 Setting up an Armature . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394.2 Setting up Inverse Kinematics . . . . . . . . . . . . . . . . . . . . . . . . . 49

5 Shading 55

6 Lighting 61

7 Rendering 65

7.1 Placing the render camera . . . . . . . . . . . . . . . . . . . . . . . . . . . 657.2 Evaluating and Finalising Render . . . . . . . . . . . . . . . . . . . . . . . 65

8 Parting Words 71

9 Troubleshooting 75

10 What next? 77

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Contents

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List of Figures

2.1 Blenders default User Interface with annotations. . . . . . . . . . . . . . . 152.2 User Preferences Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

3.1 Research on Google . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243.2 Research on Youtube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243.3 The sketch of the scene. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343.4 The sketch of T4 object to aid in modelling process. . . . . . . . . . . . . 35

3.5 A render of T4 with no armature and plain material. . . . . . . . . . . . . 363.6 The background, which is made out of a subdivided plane is shown in editmode. The T4 object stands on the background object. . . . . . . . . . . 38

4.1 Blender displays the rotational limit of the joints in Pose mode. . . . . . . 534.2 A render of T4 with armature. . . . . . . . . . . . . . . . . . . . . . . . . 54

5.1 Shading menu in Buttons window with material button enabled. . . . . . 565.2 The head object with no material assigned to it yet. . . . . . . . . . . . . 575.3 The parameters to setup the transparency material, with Shaders menu

detached from Mirror Trans and SSS menus. . . . . . . . . . . . . . . . . . 585.4 The material setup of the background object. . . . . . . . . . . . . . . . . 59

6.1 Three point light setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 626.2 Shading menu in Buttons window with lamp button enabled. . . . . . . . 63

7.1 Render settings in Buttons window. . . . . . . . . . . . . . . . . . . . . . . 677.2 It is recommended to do a small render at 25% size for a quick assessment. 687.3 Authors render of T4 object with transparency material and three-point

lighting applied in the scene. . . . . . . . . . . . . . . . . . . . . . . . . . . 69

8.1 An alternate purpose of T4 project, an advertisement of a jewellery shop. 728.2 Another possibility of T4 project, a poster of a talk. . . . . . . . . . . . . 73

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List of Figures

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List of Tables

2.2 Commonly used shortcuts in Blender . . . . . . . . . . . . . . . . . . . . . 18

6.1 Authors setting of each light. . . . . . . . . . . . . . . . . . . . . . . . . . 64

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List of Tables

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1 Introduction

This manual shows how to do 3D modelling, shading, posing, lighting, and rendering inBlender. You should download the publicly available software to your PC, see sectionon page 3, before you begin. The primary goals of this manual is to introduce the basicsof creating high impact 3D images for publications or grant proposals, to students andstaff, by using Blender. Previous experience in 3D modelling, texturing, photography,animation or programming is helpful, but not necessary.

Because of the scope and the sheer amount of information that can be provided here,

this manual only provides a brief overview of creating a simple 3D image. The authorsuggests going through the manual with a copy of Blender running on your computer. Itis a good idea to read through a section before trying it on Blender. In this way, you willhave a better picture of what you will carry out by the end of a particular section. As youprogress through the chapters, less hotkeys will be mentioned. For example, Section 2.2we read use [x] key to delete the box, as you progress, you will read only instruction,such as, delete the box.

The next chapter begins with a short introduction to Blender User Interface (UI) and thehotkeys. Blenders UI might seem overwhelming at first due to the number of buttonson the screen and little resemblance with other applications. However, this manualencourages you to memorise some of the shortcut keys to manipulate the scene, insteadof locating all the control buttons one by one. While it is possible to click on the icons toperform actions, as you become proficient in 3D graphics, youd rather use the shortcutkeys. For example, to translate an object up 10 units you need to select the object,move the mouse to the translate button, click on translate button, move the mouse tothe transformation handle, and pull the transformation 10 units upwards. These actionsmight take more than 10 seconds to complete. When you use the shortcut keys, theseactions can be performed quickly; select object, press [g][z][5], and press enter to confirm.

The reminder of the chapters follows with 3D modelling, rigging, shading, lighting andrendering. The last two chapters deals with troubleshooting and additional resources forfurther learning.

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1 Introduction

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2 Blender

2.1 User Interface

Blenders User Interface (UI, Figure 2.1) that comes with the default setting has twovisible windows: 3D window and Buttons Window. You will often access these twowindows throughout the book. This manual does not cover every components of the UI,only those that are needed for this project. Familiarise yourself with Blenders UI beforemoving on to the next section.

Marker Description

a

When you click this drop down menu, a fewmodes will be displayed on the screen.Texture Paint mode allows you to createdrawings on the object. Vertex Paintmode allows you to create colour on thevertices, in conjuction of the colour tocreate additonal effect, such as shadows.Sculpt Mode allows you to do a 3D

digital sculpting on an object. OnlyObject mode and Edit mode will becovered in the manual, the other modes aremore advanced. By default, you will be inObject mode. In Edit mode you canchange the subcomponents of the objects(vertices, edges, faces) to alter the shape ofit. Weight Paint mode is commonly usedto create or fix deformation of 3Dcharacters.

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b

This is a button that changes that wayBlender display the 3D ojects on thescreen, and it will not be mentioned muchthroughout the manual. However, from the

given screenshots, you should be able to tellwhich mode the author used for themodelling process. Throughout Chapter 3and 4, you are likely to switch betweenSolid and Wireframe display to assess the3D shape of the object.

c

Blender offers various pivot modes to assistyou in moving around in 3D space and themodelling process. The actual use can befound later in chapter 3. For now, simplyleave it on Median Point.

d

Within the Button Window, there are other6 panels: Logic (F4), Script, Shading(F5), Object (F7), Editing (F9) andRender (F10). Please leave the Editingpanel enabled throughout Chapter 3 and 4.The content of the Buttons window willchange depending on your actions orselection in the 3D Window.

e

Blender offers many types of window, which

will not be covered in this book. You cansplit more windows in Blender by movingthe mouse cursor to the edge or border of awindow and press MMB, and click onSplit Area. You may explore what is ineach Window type, however, please havethe 3D window and the Buttons windowready for 3D modelling process.

2.2 Setting up Blender for first time use

If this is your first time running Blender on your computer, please read on. Otherwise,you may skip this section. When you launch Blender for the first time, by default youwill start with a cube, a lamp and a render camera (not visible by the default zoomlevel), looking from the top view-port as shown on Figure. 2.1). This section shows a

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2.2 Setting up Blender for first time use

Figure2.1:BlendersdefaultUserInterfacewith

annotations.

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2 Blender

configuration that enables you to orient yourself in 3D space easily.

Move your mouse cursor to the border of the 3D window and the top menu bar, untilyour cursor becomes a two-headed arrow, then pull it down to see the user preferencemenu, see Figure. 2.2. Click on View and Controls button to bring up option for

view rotation setting. Enable Turntable, Auto Perspective, Around Active andView Name buttons, as shown in Figure. 2.2). Now Blender is ready to use with thesettings to make your work easier. You may slide the user preference menu back up.Importantly, save your setting with File, Save Default Settings or hit Ctrl + U.From now on, whenever you restart Blender you will not have to re-enable these settings.

2.3 Hotkeys and simple exercises of Blender

Table. 2.2 shows the list of commonly used hot keys in Blender. At this stage, please

familiarise yourself with the keys listed in table (in given order), before moving on to 3Dmodelling. Please attempt the exercise at the end of this section before proceeding tothe next. This exercise will help you greatly in manipulating objects in Blender. Beforeattempting each exercises, press [Shift][c], followed with [c] key to center the view-portand reset the 3D cursor at the origin (0,0,0). More hotkeys will be provided as neededthroughout the manual. By the end of exercise no.5, you should have a basic idea of howto navigate in the 3D space, object transformations, and editing.

2.3.1 Exercise 1. Orientation in 3D space, selecting and creating object.

Do not proceed until this exercise is fully mastered.

1. Start a new scene by pressing [Ctrl][x] keys.

2. Select the box object at the origin with [RMB]. It will be highlighted with pinkcolour.

3. Drag [MMB] to dolly around the object vertically, 360 .

4. Similarly use [MMB] again to dolly around the object horizontally, 360.

5. Zoom out until you cant see the box anymore, by using the mouse wheel.

6. Press [Numpad.] to focus back on the box. This focuses the view-port on theselected object.

7. Use MMB to get into perspective view, where the x-y grid touches the middle partof the screen with z-axis points up.

8. Pan the camera so that the box object touches the right side of the monitor, byusing [Shift] and drag MMB.

9. Pan the camera so that the box object touches the left side of the screen.

10. Pan the camera so that the box object sits in the middle of the screen.

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Figu

re2.2:UserPreferencesMenu

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Key / Mouseaction

Function

LMB click onview-port

Set position of 3D cursor.

MMB drag onview-port

Dolly view-port.

Ctrl + MMBdrag

Zoom view-port. Rolling the mouse wheel does thesame.

Shift + MMBdrag

Pan view-port.

g Translate tool. Type [g][x] to constrain movement inx-axis, [g][y] to constrain movement in y-axis, and [g][z]constrain movement in Z axis. For greater accuracy, youmay add the value after specifying the constrain axis.For example, [g][z]-5 [enter], will move the object upalong z-axis 5 units.

r Rotate tool. It has similar features to othertransformation keys: g, r, and s.

s Scale tool. It has similar features to othertransformation keys: g, r, and s.

TAB On selected Object, toggles between object mode andedit mode.

Numpad 7 Switch to top view.

Numpad 1 Switch to front view.

Numpad 3 Switch to right side view.

Numpad. Focuses the current view-port to selected object(s).

Space bar Displays a compact menu in 3D window.

a Toggles select all or none.

b Rectangle selection.bb Ray-cast / Paint selection mode

Table 2.2: Commonly used shortcuts in Blender

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11. Switch to right orthogonal view with [Numpad 3] key.

12. Switch to front orthogonal view with [Numpad 1] key.

13. Back to top orthogonal view with [Numpad 7] key.

14. Deselect the box object by pressing [a] key. You should end up with a view that issimilar to what you started out with.

2.3.2 Exercise 2. Transformations, deleting and creating primitives.

Do this exercise slowly at first and increase the speed gradually. Do not proceed untilthis exercise is fully mastered.

1. Start a new scene by pressing [Ctrl][x] keys.

2. Use [MMB] to get into perspective view, where the x-y grid touches the middlepart of the screen with z-axis points up.

3. Select the box with [RMB].

4. Press [x] to delete the box.

5. Create a monkey primitive object by pressing [space bar] key, select add, mesh,and click monkey.

6. Rotate the monkey to face you by, pressing [r][x]90, and [enter] key.

7. Make the monkey half the size by pressing [s]0.5 and press [enter] key.

8. Deselect the object by pressing [a] key. Now the monkey should be in the origin(0,0,0) and looks at you.

2.3.3 Exercise 3. More on transformations and object selection.

Do this exercise slowly at first and increase the speed gradually. Do not proceed untilthis exercise is fully mastered.

1. Start a new scene.

2. Delete the box, the lamp, and the default render camera.

3. Use MMB to get into perspective view, where the x-y grid touches the middle partof the screen.

4. Create 2 monkey primitives.

5. Space them apart 5 units (from their centers).

6. Transform one monkey to be 2 times bigger along z-axis than the other.

7. Rotate both monkeys to face you.

8. Use rectangular selection [b] key to select both monkeys on the view-port. Alter-natively, LMB on monkey and [shift] select the other.

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9. Move them 1 unit along z-axis.

10. Deselect them by pressing [a] key. Both monkeys should be 1 unit higher than theprevious position.

2.3.4 Exercise 4. Object editing, selecting and transformations.


2. Select all objects by pressing [a] key, then delete them.

3. Use MMB to get into perspective view, where the x-y grid over the distance ap-proximately touches the middle part of the screen.

4. Create a monkey primitive object.

5. Rotate the monkey object to face you.

6. Use MMB to get into perspective view, where the x-y grid touches the middlepart of the screen.

7. Get a good close look at the nose.

8. Press [Tab] key to get into the edit mode. Now, in edit mode you can change theappearance by modifying the vertices, edges or polygons.

9. Now we want to make the nose bigger by modifying the polygons. Press [Ctrl][Tab]key. This displays the selection-mode. Currently, we are in vertices selection mode.Select option number 3, faces.

10. All faces are selected by default on new object. Clear all selection by pressing [a]key.

11. Select 4 polygons at the tip of the nose.

12. Scale them twice the size and move them -1 unit along y-axis. The monkeys noseshould be bigger, longer and points toward the screen. Use [s] key for scaling, and[g] key for translation. Take note here that all transformations keys ([g],[r], and[s]) are applicable also in the edit mode.

13. Deselect everything, by using [a] key.

14. Select everything by using box selection key, [b] key, draw a rectangle to cover theentire monkey.

15. Deselect everything.

16. Select all polygons on the monkey by using [b][b] key. This is the paint selectionmode. The circle on the screen shows the radius of selection, and use LMB to startpainting/selecting faces on the monkey. If the radius of selection too small, youmay increase it by using the mouse wheel. Keep on paint-selecting until all thefaces are selected.

17. Deselect everything.

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18. Press [Tab] key to leave edit mode. Do not create a new object in edit mode, thatnew object will be part of the ob ject that you are currently editing. Always leaveedit mode when you are done with editing.

2.3.5 Exercise 5. More on object editing.


2. Select all objects by pressing [a] key, then delete them.

3. Use MMB to get into perspective view, where the x-y grid touches the middle partof the screen.

4. Create a monkey primitive object.

5. Rotate the monkey object to face you. Select the monkey if it is not alreadyselected.

6. Delete the other half of the monkey. Firstly, you must be in the edit mode, andselect all the faces on the other half and press [x] to delete. To select the faces, youmay use, [b] or [b]-[b], it is up to you, as long as you can do it fast.

7. Make the ear of the other half by 1/2 the size. Correct placement is not importantat this stage. Make sure that it is smaller then the original size. It is up to you ifyou want perform the editing on the vertices, edges or faces. By now you shouldhave a half-monkey on the screen.

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3 3D Modelling

3.1 Scene Preparation

It has never been a good idea to plunge ourselves into a 3D software without knowingthe object we are creating. Although scene preparation could take more time than themodelling process, this step is very crucial in terms of production time. The followingare some of the important questions that we must consider carefully:

What is the object?

How will the object appear in the scene?

How close will it be from the camera?

What is the background for the object?

How will the image appear on publication?

What is the layout; landscape or portrait?

What is the size; A4 or A0?

100% accurate model, or a simplified model?

An initial research on the subject matter is important to get the idea of the shapeand appearance of the object. Google (Figure 3.1) and YouTube (Figure 3.2) are goodresources to search for example images. Familiarising yourself with the shape is veryimportant before sketching and 3D modelling process. As familiarity increases, the 3Dmodelling process becomes easier. We will not be making a 100% physically accuratemodel, since that would be difficult at this stage. We will create a simplified model.Ill leave the creation of a 100% physically accurate model for your own exercise afterwalking through this manual.

In this project, we have defined the object to be T4 Bacteriophage. For simplicity, Iveprovided a sketch as shown in Figure 3.3 of how the scene would appear in a landscapeformat. In this manual, two objects will be created, the virus itself and a simple back-

ground object. However, depending on your familiarity with Blender at the end of thismanual, you may improve the overall design of the scene. I would normally do sketcheson paper. In this case I used Inkscape (www.inkscape.org) instead. Study the sketchesas shown in Figure 3.3 and 3.4. In the scene that we are creating, the T4 will be shown asif it lands on flat plane. In Figure 3.4, Ive identified the basic shapes that make up theshape of T4. You will use this figure as an aid to create the T4 object. The head part isan icosahedral shape. The tail resembles a cylinder shape. We will use only one 6-sided

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Figure 3.1: Research on Google

Figure 3.2: Research on Youtube

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3.2 Modelling the shape of T4 Bacteriophage

cylinder for the tail part, since all need to be the same objects. We will do extrusionalong the tail part to create the whiskers and the fibre tails.


Please read through this section entirely before attempting it on Blender. If you are newto Blender, do not attempt this part without completing section 2.3. Throughout thissection, even it is not explicitly mentioned, you will switch between perspective view (bydragging MMB around) and front orthogonal view (by pressing Numpad1 key) manytimes in assessing the shape that you are creating.

Stepno. Screen-shots Descriptions

1Delete the default box inthe scene.

2

Switch to front orthogonalview by pressing

Numpad1 key and loadthe background image tohelp you in the modellingprocess by clicking View,Background images (apanel will appear on your3D window), Usebackground images andload the backgroundimage sketch.png that isprovided with this manual(T4_Bacteriophage_Project.zip).Change the Blend valueto 0. Let the Backgroundimage panel floats on yourscreen for now.

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3

Position the backgroundimage of the T4 object, sothat the bottom part of itsits at the origin.

4

Create an icosahedron bypressing, [Space Bar],Add, Mesh, Icosphere,set the subdivision to 1.Move it to the designatedplace as marked by thebackground image.

5

Create a 6 sided cylinder,by pressing [Space bar],Add, Mesh, Cylinder,enable Caps and set thenumber of vertices to 6.

Scale and position thiscylinder to the designatedplace according to thesketch. Rotate thecylinder -15 degrees alongz-axis.

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6

The cylinder does not

have sufficient number ofsurfaces to work on. Wemust subdivide thecylinder along the lengthof the cylinder. While the6-sided cylinder is stillselected, enter edit modeby pressing [Tab] key.Switch to edge selectionmode by pressing,[Ctrl][Tab], 2.

7

By now, all edges of thecylinder are selected,press [a] key to deselectthem all. Now, select onlythe vertical edges of thecylinder and press [w],click Subdivide Multi,set number of subdivisionto 3.

8

Now you have 3 new setsof edges on the cylinder.Move the new set of edgeson top, to the top of thetail sheath, just below thewhiskers.

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9

Move the new set of edges

at bottom, to the bottomof the tail sheath, justbelow the tail fibres.Lastly, the new set ofedges in the middle,downwards, slightly abovethe tail fibre. We will doextrusion on these newlycreated faces to create thewhiskers and the tailfibres.

10

Let us now make theplates (or the disc shape).The first one is for thewhiskers, and the otherone below is for the tailfibres. Now, select the6 faces on the top of thecylinder.

11

Now, we want to expandit along xy-plane. Press[e] key for extrusion menuand choose Region.

12

If you move the mouse,the extrusion do notappear correct, this isfine.

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13

Quickly press [Esc] thenscale the newly createdfaces (which you cantsee) along xy-plane, bypressing [s][x], input 2.5,[enter], followed with,[s][y], input 2.5, [enter].

14You should havesomething similar to theimage shown on the left.

15

Do the same procedurefor the bottom part of thecylinder. You should endup with a dumb-bell

shape as shown on theleft.

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16

Let us make the whiskers

by using 2 extrusions.Select the 6 faces of thetop dumb-bell, and doextrusions on individualfaces, press [e], and clickindividual faces.Extrude this one about1/3 length of thewhiskers. Switch thepivot mode toIndividual Centers.

Now press [s] to scale thefaces individually.If the faces are not scalingin respect of their owncenters, it is because youdo not have the pivotingmode asIndividual Centres.

17

Do another extrusionuntil it reaches the fulllength of the whiskers.Scale down the faces atthe tip too.

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18Your model shouldresemble the image shownon the left.

19Do the same procedure ofcreating whiskers in orderto create the fibre tails.

20

The first extrusion shouldbe just short, not morethan the ball joint asshown on the backgroundimage.

21

The subsequent extrusionshould reach only at theball joint marked on thesketch.

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22Now create 3 extrusionsat the joint for a betterbending effect.

23

Extrude the faces from

the joint all the way tothe length of the fibretails.

24

Scale down the tip of thefibre tails. If your scalingis messy, it is because youdo not have the pivoting

mode asIndividual Centres.

25

At this stage you shouldhave your object similarto image shown on theleft.

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26

Is it not entirelycomplete, we still need tocreate that teeth-lookingobject at the bottom ofthe cylinder.

27

Select 6 faces at thebottom of the cylinder asshown on the left. Switch

the pivot mode toIndividual Centres, ifyou happened to switchedinto different pivotingmode .

28

Press [e] to extrusion, andselect individual faces.Extrude them down, andscale them down.Remember, if the faces

are not scaling in respectof their own centers, it isbecause you dont havethe pivoting mode asIndividual Centres.

29At this stage, you shouldhave created the T4object as shown.

Save your work frequently. This is the end of the 3D modelling phase. The T4 modelis at its default pose. So why did the author specify the default pose as such? Why

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Figure3.3:Thesketchofthe

scene.

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Figure3.4:Theske

tchofT4objecttoaidinmodellingprocess.

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Figure 3.5: A render of T4 with no armature and plain material.

not all fibre tails up or down, or even bent? The reason was that the modelling processand rigging would be simpler and visually nicer. Rigging is a term to signify a processof setting up an armature, which contains bonesto pose or animate a 3D object. In thenext section, we will prepare an armature, which enables us to pose the T4 object asshown in Figure 3.3.

3.3 Modelling the background

Modelling the background or the 3D environment is as crucial as the main object itself.Normally, stage or world design is separated from character design. Many books on themarket treat these two subjects separately. However, the background of the T4 objectis simple enough to be included in this chapter. Why do we need a background? Tocreate and support the atmosphere of the storyline, which the director has in mind. Forexample, to show off the piloting agility of the main hero, the director would pick adifficult terrain to portray the scene, such as; narrow canyons or underground caves.

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3.3 Modelling the background

In this project, we want to accentuate the 3D presentation of T4 object. For this reason,we will use a dark-coloured background. This background will receive lights and shadows,which will enhance the depth of the image (otherwise it will look plain and boring).

To create the background object as shown in Figure 3.6, follow these steps:

1. Create a plane

2. Position the plane to touch the fibre tails of the T4 object

3. Switch to Edit mode

4. Switch to Edges selection mode

5. Select the edges where the bending will occur

6. Press [w] key to bring up the special menu

7. Choose Subdivide Multi, and set the number of subdivision to 6

8. Translate one edge at a time to obtain the backdrop shape

9. Switch to Object mode

Once you have the background in your scene, click [smooth] button in Buttons window.Bear in mind, this button DOES NOT smoothen out objects, it only change how thelights will act on that object. By enabling this button, this object will appear smoother.You should be able to make this easily after completing the previous section.

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3 3D Modelling

Figure3.6:Thebackground,whichismadeoutofasubdividedplaneisshownineditmode.TheT4objectstandsonthe

backgroundobject.

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4 Rigging

Rigging is the process of setting up bones for posing or animating objects. Think of itas bones and muscles in your body. Bones are 3D objects that deform other objects. Inthis chapter we will learn how to create an Inverse Kinematic (IK) setup. Why IK andnot using Forward Kinematic (FK)? If you have a robot arm with 8 joints, with FK, youhave to rotate the joints one-by-one to get the robots hand to reach a point in space.With IK systems, you put the robots hand where it would be in a space, then all jointswill be automatically calculated. Thus, IK simplifies posing objects greatly. We will

create a simple rig to pose the T4 objects as shown in Figure 3.3.

4.1 Setting up an Armature

Stepno. Screenshots Task descriptions

1

If the 3D cursor is not atthe origin, please reset theposition of the 3D cursor.

Create subdivisions alongthe vertical shaft of theT4 object, with 3 cuts.This can be done byselecting the edges inEdit mode and press [w]key to bring up thesubdivision menu.

2

Switch to right orthogonal

view. Lets add anarmature by pressing[Space Bar] key and pickArmature. Press [TAB]to enter into edit mode.

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4 Rigging


3

Extrude the bone

twice towards theicosahedron. This can bedone by RMB click on thetip of the bone, and press[e] key to extrude. Youmay press [e][z], toextrude the bonevertically along z-axis.

4Now, extrude a bone tocover the entire length ofthe head of the T4 object.

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5

Now you should have an

armature of four bones.Please name the bonesproperly to distinguishwhich one is which.RMB click onthe body of the bone andthere should be an

Armature Bones menuin the Buttons Window,underneath your 3Dwindow. Name them as

(from the bottom)tailSegment1,tailSegment2,tailSegment3, andhead.

6

Select the bottom node oftailSegment1 bone, andextrude towards positivey-axis. This will be theroot bone, which all otherbones will be attached toeither directly orindirectly.

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4 Rigging


8

Click the body of the root

bone, and under Armature Bones menu,change the name of thebone to root. Move thisbone out of the way,which enables us easily tograb the bone later whenneeded to pose or animatethe object. Since thisbone will not deformanything, disable the

Deform button and makesure that the bone is achild of [] (choose blank).

On the other hand, youmust set the

tailSegment1 boneas child of root bone.Since these two bones arenot attached, enable theOff(set) button.

9

The bones in thearmature should be inthis hierarchy:root

tailSegment1

tailSegment2

tailSegment3

head

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10Your armature shouldnow resemble the imageon the left.

11

We will now beginenveloping process byspecifying how much the

bones will influence thevertices of the T4 object.Switch the bone displayfrom octahedron toenvelope.

12

Enter the edit mode, ifyoure not in that mode,and start modifying theenvelope by RMB click

on the bones node,followed with [s] key.

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4 Rigging


13

Please make sure that the

head and the tailsegments are coveredwithin, at least, the whiteenvelope. Beyond thewhite envelope, theinfluence value is 0.Within the whiteenvelope towards thebone is between 0 and 1.As for the whiskers part,make sure that they are

covered by the whiteenvelope of the lowernode of the head bone(or the upper node of thetailSegment3 bone).

14

Now, let us set theicosahedron and thecylinder object to respondto the envelope, whichyou set up earlier. Switchto Object mode. Select

the icosahedron, thenclick Add modifiersbutton and Armaturefrom the pull-down menu.Now, enter the name ofthe armature object in theOb: field as Armature.

Repeat these steps for thecylinder as well.

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15

Now, lets test the

deformation by selectingthe armature, and switchto Pose mode.

Posing with the bonesdrawn as octahedron orenvelope will obscure theview a lot. Changing thedrawtype to Stick (inButtons window) isrecommended at thisstage.

Rotate the bones one at atime and examine thedeformation. If youre nothappy, go back to editmode and modify themthere.

16Inspect the deformationfrom all angles.

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4 Rigging


17

Switch to front ortho viewand place the 3D cursorwith LMB at the base ofthe fibre tail as shown.

18First extrusion, extend itup to the ball joint asshown on the sketch.

19

Extrude the bone again tothe tip of the tail fibre.Make an angle betweenthe first bone and thesecond bone. A slight

bent will assist Blender todeform the bone in thecorrect direction as wewant the fibre tail willbend in a hat (^) shape,not a V shape..

20

Still in edit mode, switchthe bones visualisation toEnvelope and adjust theenvelope of the bones.

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21

Since the fibre tails are

very thin, scaling downthe envelope would stillleave a big envelope.Simply change thedistance value , underArmature Bones menu inButton Window, to 0.1.

22

Now, you should have an

armature resembling tothe image shown on theleft.

23

At the tip of the bonethat deforms fibre tail,extrude another bonetowards x-axis. We will

use this bone as an IKhandle.

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4 Rigging


24

Under Armature Bones

menu, disable deformbutton, as the IK handlewill not deform theobject. Give it a propername, such astailFibre1_IK, andmake it to be child ofnothing. This is how tosetup a bone to act as anIK handle, which you canuse to animate a chain of

bone easily.

25

Before we move on, makethe tailFibre1a bone to bethe child of tailSegment1bone. This way, when wemove the root bone inPose mode, the tailFibre

bones will be moved aswell.

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4.2 Setting up Inverse Kinematics


Step

no. Screenshots Task descriptions

1

Lets continue from theprevious section. Youshould have an armatureresembles to the image onthe left.

2

Switch to Pose mode.Select the IK bone, thenhold down [Shift] buttonto select the tailFibre1bbone, and press [Shift][i]to add an IK constraint.

3

The tailFibre1b bone isnow marked with yellowcolour, which signifiesthat it has an IKconstraint in place.Change the value ofChainlen(gth), underConstraints menu, to 2.

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4 Rigging


4

Now you should test the

IK setup by movingaround the IKbone/handle. Does itdeform properly? If itdoes, switch back to editmode, and duplicate thesebones (tailFibre1a,tailFibre1b,tailFIbre1_IK to othertail fibres. Do this byswitching first to top

ortho view, select thebones, and then use[Shift][d] to duplicate 3bones at a time.Translate and rotate theseduplicates to other fibretails that has no bonesyet, until all fibre tailshave bones in them.Name these duplicatesproperly, e.g., fibre-

Tail1a...fibreTail5a, andso on.

5

After correcting thenames of all the bones,select all the bones andpress [Ctrl][n], and clickon Clear Roll (z-axisup) to reset the rollposition of the bones.After extrusions, bonesmay have different roll

value. Before posing,always reset bone rotationby doing [Ctrl][n].

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6

Check if the z-axes of the

bones (of the fibre tails)point up by enabling theAxis button. Whenfinished, switch back toPose mode.

If some axes do not havez-axis upwards, bring upthe transformation panelby pressing the [n] key,select the bone withz-axis that pointsdownwards, simplychange the roll value to 0.This step is important forthe bones of the fibre tailsas we will be setting their

rotation limits. As for thebones on the tail sheath,you cant have the z-axesto point up due to theorientation of the bone.

5

For tailFibre1a ...tailFibre5a, set the bonerotation limit as shown onthe image below.

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4 Rigging


6

For tailFibre1b ...

tailFibre5b, set the bonerotation limit as shown onthe image below.

7

Lastly, you need to setupan IK to control the headbone, which is attached totailSegment3 bone. Forthe heads IK, use chainlength value of 4.

This concludes the rigging process of the T4 object. If youre still in Pose mode, and

press [a] key to select all the bones, Blender also shows the rotational limit of the jointsas shown in FIgure 4.1. To change the pose of your T4 object you must be in Pose mode,then select and transform the IK handles one at a time, which you set up earlier. Toreset the pose, select all the bones in Pose mode, hit [Alt][g], and [enter], to clear theposition. Immediately perform [Alt][r], and [enter], to clear the rotation value of the

joints.

You have now learnt a lot in modelling, rigging and posing in Blender, but there are plentymore to discover in Blender. Please refer to Chapter 10 for links to others tutorials tosee other techniques in modelling and rigging. What does the T4 object resemble? If welook at Figure 3.3, 3.5 and 4.2, a number of things come to mind: a microphone, a mace,a starship, a carousel (without the horses and the top canopy), an octopus, a cactus, a

spider, an ant. Do you know any others? By now, you should be able to create theseobjects with the modelling and rigging skills that you acquired thus far.

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Figure4.1:Blenderdispl

aystherotationallimitofthejointsinPosemode.

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4 Rigging

Figure 4.2: A render of T4 with armature.

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5 Shading

Shading is a separate subject on its own and many studies have been dedicated to producea realistic looking material in Computer Graphics (CG). Shading is a process of creatingsurface information of objects. Milk and metal are two different materials. These tworeflect and refract light differently (also depending on their thickness). These two havedifferent transparency and specularity. For example, in a prison scene, you will striveto create a worm-out metal look on the bars and having a milk-looking material wouldnot suit the scene at all. Blender is able to simulate the surface appearance of many

materials, metals and non-metals. In this short chapter, we will look into setting up asimple transparent material. To bring up the settings of the material in Buttons window,simply press [F5] key, and click on the material buttons, which is to the right of the lampbutton (Figure 5.1).

To create the material for the T4 object, simply follow these steps:

Select the head part of the T4 object

Bring up the Shading menu and enable the material button (red ball). If it is anew object, you wont see any settings for the materials, as shown in Figure 5.2

Click on Add New button and Blender will assign a default white material

Give the material a proper name, dont leave it as material.001, mat.00a or mate-rial.002. Who can tell what an item is where there is poor naming in the scene?

Use the material settings as shown in Figure 5.3 for the T4 object

Select the tail part of T4 object (which includes all the fibre tails)

Dont click on Add New button, instead, click on the pull down menu, and usethe material that you created previously for the head.

Use the material settings as shown in Figure 5.4 for the background object.

If you press [F12] key to render your scene, it might not look good at this stage.Lighting setup will be explained in the following chapter. If the render camera doesnot render at the appropriate location, quickly take a look at Section 7.1.

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5 Shading

Figure5.1:ShadingmenuinButtonswindowwithmaterialbuttonenabled.

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Figure 5.2: The head object with no material assigned to it yet.

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5 Shading

Figure5.3:Theparameterstosetupthet

ransparencymaterial,withShadersmenudetachedfrom

MirrorTransandSSS

menus.

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Figure5.4:The

materialsetupofthebackgrou

ndobject.

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5 Shading

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6 Lighting

If you press [F12] to render a scene in Blender without a light, you will get nothing buta black render. Similarly to the real-world, we need lights to see things. Lighting is alsoa separate subject on its own, and a form of art. A great looking 3D model with poorlighting would make the object seem dull. A proper lighting setup enables artists, oreven producers to create and convey the mood of the scene. For example, a tomb scenewould have dim lights to accentuate the eerie feeling. Now, if you increase the intensityof the lights in the cave to a bright white colour, it will feel like being in a hospital. Many

books have been written on this topic and further discussion of complex light setup inBlender can be found on the following links:

http://wiki.blender.org/index.php/Doc:Manual/Lighting

http://dl.dropbox.com/u/1393798/tutorials/lighting/general/general.html

http://dl.dropbox.com/u/1393798/tutorials/lighting/interior/interior.html

http://wiki.blender.org/index.php/Doc:Books/Essential_Blender

In this chapter, you will create a three point light setup, which is a basic light setupas shown in Figure 6.1. There are also many kind of light objects in Blender, however,we will deal mainly with the point light object. If you think that this light setup is tooboring, there is room for improvment. Feel free to do so.

Three point lighting simply refers to a technique to light up a scene by using only threelight sources. The setup is relative to your render camera. Key light is the main light inthe scene. This light has higher intensity than fill and back lights. Fill light diminishesany strong shadows or contrast caused by the key light. Back light simply adds thecontrast between the background and the object itself.

To setup a three point light in your scene, simply follow these steps:

To add a light, press [Space Bar], Add, click on Light

Position the lights as shown in Figure 6.1

Add the key light first, then the fill light, and back light.

To change the properties of the light:

Click on the button with a light bulb icon on it, as shown in Figure .6.2

Press [F5] key to switch the panels in Button window from Editing to Shading

There are five types of lights in Blender as shown in the Preview panel (Fig-ure 6.2), only enable [Lamp] button. This is Blenders point light

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6 Lighting

Figure6.1:Threepointlight

setup.

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Figure6.2:ShadingmenuinButtonswindowwithlam

pbuttonenabled.

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6 Lighting

Type of light Intensity Location Colour

Key light 1.25 x=-4.3 r=0.792

y=4.6 g=0.837

z=6.9 b=0.993

Fill light 0.65 x=9.6 r=0.985

y=4.4 g=0.875

z=3.5 b=0.744

Back light 0.5 x=-5.6 r=0.831

y=-7.5 g=0.858

z=9.7 b=0.902

Table 6.1: Authors setting of each light.

The light settings, which the author used is in Table 6.1. You may use these settings oryou may wish to be more creative. If the key light is orange, how would you complementit with the fill and the back lights to make the T4 image stand out? To see the results, youcan press [F12] key to render your scene. If you dont like what you are seeing, simplychange the lights attributes and render it again. If your camera location is awkward,and can not see the scene properly, quickly take a look at Section 7.1.

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7 Rendering

Rendering is a process of generating an image by computing the parameters defined in thescene. What we see in the 3D window is the polygon view of the object. Sometimes, wechange the display type from flat to wireframe, however these views are computationallynot intensive. These views are commonly known as real-time rendering. The non-realtimerendering, or known as pre-rendered scene, is computationally very intensive. With real-time rendering you may get a smooth interaction, up to 100 frames/sec. With a non-real-time rendering, you may have to wait up to a week for 1 frame (depending your

system configuration). When the render button [F12] is pressed, Blender computes thepolygons, the lights, the shading, camera, sky, armature, along with their interaction inthe scene to produce the resulting image.

Blender is a 3D suite with its own renderer. There are many other renderers out there thatdo more intensive calculation than Blender and gives life-like scenery, such as: Sunflow(sunflow.sourceforge.net), YAFRAY (www.yafray.org), and LuxRender (www.luxrender.net).These three programs only render, but they take 3D scene made in Blender. Please seetheir website for further information. In this manual we only use Blenders internalrenderer.

7.1 Placing the render camera

Blender starts with 1 render camera when you start a new scene. However, this defaultlocation is not the desired one at all times. You can place a render camera by moving yourperspective view (to capture the scene as you like it) and press [Ctrl][Shift][Numpad0]to move the render camera to your location. You can move the render camera by using[g] and [r] key to rotate. To see through your render camera, after moving around in thescene, simply press [Numpad0].

7.2 Evaluating and Finalising Render

There are various settings for rendering in Blender, simply press [F10] key and you willsee the menus as shown in Figure 7.1. In Format panel (rightmost), you can see thedefault size of the render in pixels. You may change these values depending on yourneed. For a half-page illustration, the values are sufficient; 1280 x 1024 pixels. For an A0publication, you want to render at approximately 15,000 x 20,000 pixels. Another setting

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7 Rendering

that you must pay attention to is the percentage value in Render panel (with the bigRender button). This percentage allows you to render smaller than the predefined size,in this case lower than 1280 x 1024 pixels.

Depending on your system configuration and the complexity of your scene, you may

have to wait for a long time to see the render window. It is always a good idea todo a small render to evaluate your scene before doing a full Render (see Figure 7.2).Occasionally, you might change the light parameters, the orientation of render camera,or the background colour. It might take quite a while to get a final render. You mightadjust the lights position or the properties to make the image stand out when you render.You might also change the position of the camera to get a better shot at the T4 object.Once you are happy with the result shown at 25% or 50% size, you may do a full-sizerender.

Please render your scene. If your scene is different from Figure 3.3 and 7.3, thats fine.To save the rendered image, click [File] on the top menu, then click on Save rendered

image. The type of image compression can be defined from the Format panel and thedefault format is JPEG at 90% quality (Figure 7.1). If your publications require a fileformat that Blender does not support, simply save as Targa (.tga) format, and useGIMP (www.gimp.org) to convert it to another format.

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Figure7.1:

RendersettingsinButtonswindow.

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7 Rendering

Figure7.2:Itisrecomm

endedtodoasmallrenderat25%sizeforaquickassessment.

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Figure 7.3: Authors render of T4 object with transparency material and three-pointlighting applied in the scene.

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7 Rendering

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8 Parting Words

This chapter concludes the T4 Bacteriophage Project, which introduced the basics ofBlender modelling suite. However, your journey in 3D graphics begins here. You havelearned the basic skills to create a simple 3D image. Creating an artwork requiresproblem-solving skills and patience. The author introduces a general flow of a 3D imagecreation using Blender: sketching, 3D modelling, shading, posing, lighting, and render-ing. Do not attempt to create any form of 3D artwork without sketches, you will bewasting valuable times in doing unnecessary modifications.

The author has only presented the basics of Blender in creating a 3D artwork. Additionalresources to learn Blender is provided at the end of this manual. The author wishes youall the best with your endeavour in making 3D graphics, for whatever purpose it maybe: visual arts, technical reports or even scholar publications. Figure 8.1 and 8.2 showalternate endings of this T4 Project. So, what are you making today?

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8 Parting Words

Figure8.1:Analternat

epurposeofT4project,anadvertisementofajewelleryshop.

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Figure 8.2: Another possibility of T4 project, a poster of a talk.

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8 Parting Words

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9 Troubleshooting

This section provides some general troubleshooting if things do not seem to work properly.

Problems Possible solutions

The scene is black when Ipress F12 to render.

Make sure that you have at least a light in your scene.

Check if the light is in the same layer with the object.

The lights intensity and distance value might be too low.

Check if the layer where the light set is enabled.

Check if the render camera is inside any object or putaway in another deactivated layer.

I cant switch totop/right/front orthogonalview

Make sure that the Numpad Lock is on.

I cant dolly the camera easily,the view-port tumbles around.

Please see section 2.2.

I dont have perspective viewwhen I dolly the camera, onlyorthogonal view.

Press [Numpad5

], and please see section 2.2.

On the exercises 1-5, I see nocube when I create a newscene.

It seems that the default configuration has been changedon your computer. Firstly, switch to top orthogonal viewby pressing [Numpad7]. Secondly, press [Shift][c], then[c] to reset the location of 3D cursor at the origin andcenters the view-port. Lastly, create the cube bypressing [Space bar] key and select, add, mesh, cube.

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9 Troubleshooting

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10 What next?

The author has provided some links at the end of this manual for advanced topics inBlender. Blender is not limited only to 3D modelling, posing and rendering. Youcan use Blender to create physical simulations, such as fire, smokes, rigid body, softbody (hair and clothes) and fluid. In addition, Blender is also a 3D engine that al-lows you to create interactive 3D simulations and presentations. Blender has beenused extensively on various open projects such as Elephant Dream and Big Buck Bunny(http://www.blender.org/features-gallery/blender-open-projects/). Open projects allow

you to download the entire production set in Blender file format for learning pur-pose. Thus, you can learn more about setting up scenes from the experts. The nextplace to learn about advanced topics in Blender is: http://www.blender.org/education-help/tutorials/.

The author also recommends to look in other 3D softwares tutorials. Although you maynot be able to replicate the steps in Blender, you can replicate the method by usingBlenders features. You might find a particular method that would be more efficient tocreate your scene.

After browsing the links at the end of this manual, you would have more ideas of yournext 3D projects and how to accomplish many tasks in Blender. However, as previouslymentioned, you must begin with sketches. There are are many approach to set up a 3Dscene, but a careful planning will greatly cut the production process.

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10 What next?

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Acknowledgment

The production of this resource was supported by the Australian Research Council Nan-otechnology Network Early Career Book Project.

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Appendix A: Additional Resources

Blender tutorials:

http://www.blender.org/education-help/tutorials/

http://wiki.blender.org/index.php/Main_Page

http://www.blenderartists.org/forum/

http://www.blenderart.org/

Blender materials:

http://www.blender-materials.org/

http://matrep.parastudios.de/index.php

General 3D tutorials in lighting, compositing, shading,

texturing and rendering:

http://www.3dtutorials.sk/

http://www.subdivisionmodeling.com/blogger/

http://www.3dm3.com/

http://www.cgsociety.org/

http://forums.3dtotal.com/

http://www.3dlinks.com/

intoduction to blender

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