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Wiley 3D for Graphic Designers

1. but for now if the behavior is difficult to use you can click Action Center above the viewports and select Selection Center Auto Axis This ensures that the tool han dles remain in the center of the object and still align to the x y and z axes Next let s consider the Rotate tool The handles for this tool are circles Each circle is colored like the circles on the Move tool Clicking and dragging on these rotates the object perpendicular to the axis of the corresponding color Again the active handle turns yellow Clicking off the handles snaps the tool to the click point and dragging free rotates the object in all directions at once This type of rotation is very difficult to control and is not recommended The gray circle that encompasses the rest of the handles rotates the view and rotates the object perpendicular to the current view In the orthographic viewports the gray circle is no different from the colored handles but in the perspective views this will rotate variably based on the angle of view This is a pretty special use but when it is needed it can come in quite handy Because rotation by its very nature takes place around an axis there is no way to rotate in a single direction and so there are no separate axes at one time as with the Move tool The hot key for the Rotate tool is E Pressing and holding the Ctrl Control key prior to clicking a rotation handle causes the angle of rotation to snap to 15 degree incremen
2. e R Scale tool e Y Transform tool In the next chapter you will start creating 3D objects You will look at object primi tives and all of their options that enable you to control their size proportions and struc ture This will also give you the opportunity to explore some additional sections of the modo user interface On the DVD for this chapter are practice files and videos covering the topics discussed in the previous pages These short videos show tools and procedures in action to help accelerate the learning process
3. on this tab Practice Moving Objects Open the file Transform_Practice 1xo from the included DVD The file contains six cubes in individual layers When in individual layers each object can be moved separately when in Item mode 1 Enter Item mode by clicking the Items button above the viewports next to Vertices Edges and Polygons 16 CHAPTER 1 WORKING IN 3D Figure 1 11 Final position and orientation of the six cubes Select a layer either by clicking on it in a viewport or by clicking on it in the Items list tab on the upper right side of the screen To move more than one layer at a time Shift click on it in the item list Use combinations of the Move Rotate Scale and Transform tools to get the cubes into the positions shown in Figure 1 11 Review This chapter has covered an intro to 3D space as well as the basics of moving around our viewports and objects in three dimensions You have looked at some of the basic sections of the user interface UI and learned some important hot keys With the large number of tabs menus and buttons in the interface learning hot keys can be important to a quick and efficient workflow Here are the hot keys to recap Alt Shift click Option Shift click pan view Alt Ctrl click Option Control click zoom view Alt click Option click rotate view A center view on all visible items ShifttA center view on selection REVIEW 17 e W Move tool e E Rotate tool
4. panning zooming and rotating the canvas Interestingly the addition of just one more navigational feature significantly complicates the way that we interact with the environment Panning and zooming are relative to the perspective of the user so they do not change much There are two ways to pan in 3D space by clicking and dragging on the pan icon in the upper right corner of the view or by holding Alt Windows or Option Mac while clicking and dragging Zooming can be achieved via one of three methods As with the pan tools there is a zoom widget in the upper right corner this one zooms directly toward the center of the view Holding Alt Ctrl Windows or Optiont Control Mac while clicking and drag ging zooms based on the position of the cursor By using this method with the right mouse button a zoom area can be selected This creates a box and the area inside will Figure 1 6 9 The modo user interface 10 CHAPTER 1 WORKING IN 3D Figure 1 7 Flat front view of a model zoom to fill the view after the mouse button is released Finally you can zoom with the scroll wheel This last option is also context sensitive and will zoom toward the cursor position While in the camera view using the Alt Ctrl Optiont Control key combo with the right mouse button adjusts the focal length of the camera and enables you to zoom in and out as opposed to actually moving the camera in and out in space The real complication
5. without perspective of any kind This means that objects located farther from the viewer will not appear smaller as the distance increases An orthographic view is similar to a floor plan or elevation in architecture Because it lacks the distortion associated with perspective this type of view is ideal for creating and aligning objects Modo offers different interface layouts under its viewport tabs Model Quad gives us three orthographic views and one perspective view Although these two dimensional views are initially set to Top Front and Right views they can be changed to any other angle Bottom Left or Back and to views that include three dimensional perspective Perspective views enable you to see objects and scenes with real depth There are options to use an arbitrary perspective the default in the Model Quad layout camera perspective based on the default scene camera or any additional cameras that have been added in the creative process or light perspective You can completely adjust the first Figure 1 2 3 Three dimen sions from a map perspective 4 CHAPTER 1 WORKING IN 3D option without changing the scene in any way but it is important to note that both cam era and light perspectives are tied to actual objects in 3D space Thus if you move these views you will actually be moving or rotating objects and changing the makeup of the scene Movement in camera and light perspectives can be reversed with the U
6. CHAPTER 1 Working in 3D T he mti al impuls for someone interested in learning 3D graphics is to immediately jump in and start building trust me I have been there While there is definitely something good to be said about diving right in if you spend a little time cre ating a foundation of skills you will have less need to break bad habits later Before you start creating anything you need to understand the canvas you will be working with and the elements that will be used in the creative process This chapter covers the following Understanding 3D space Exploring a 3D scene Navigating the modo user interface and its viewports Maneuvering views and objects in space 2 CHAPTER 1 WORKING IN 3D Figure 1 1 Three dimensions froma screen perspective Understanding 3D Space Maneuvering in 3D space can seem easy at first glance After all only one dimension has been added to the standard page layout and that dimension is what we experience as we move around every day However believe it or not the addition of this dimension can make navigation harder to get used to for the novice 3D artist If you don t grasp some foundational principles from the outset you can become disoriented and lose track of your model and scene The addition of a third dimension adds much more than just another arrow on the monitor A standard page layout has two axes x and y If these equate to the horizontal and vertical directions respe
7. NTERFACE Traditional lights in 3D space use simple math to add brightness based on an area of influence light color and intensity These lights come in common variations that are seen in most 3D applications Distant lights sometimes called directional lights are similar to the sun The actual light comes from infinitely far away and is adjusted by the angle it enters the scene Spotlights simulate their real world namesake Point lights are similar to lightbulbs and cast light outward from a single point in all directions evenly Area lights are similar to soft boxes used in studios Other lights are more situational and are covered in depth along with the other lights mentioned here in the following chapters Radiosity is also known as global illumination because illumination comes from other angles than just the direct light source In this lighting model light is based on light particles known as samples which project into a scene much like real world light As with light particles in the real world these samples can bounce off surfaces to provide illumination in areas where a light does not have a direct effect Each bounce of light adds an order of complexity to the calculation and as a result causes a slower render time Because light samples are blended together for the final result using more of them creates a smoother finished look and like other quality improving options slows the final image production In general a combin
8. ation of both lighting types gives the best quality and control However there are times when using just one or the other can deliver excellent results The Camera The camera in a 3D scene gives the viewpoint for finished images Cameras appear only as representations in the scene and will not appear when a finished image is rendered so you don t have to worry about them showing up in reflections Cameras offer control over many of the options that physical cameras have You can control focal length lens distortion f stop film back and shutter speed Although they are simple cameras are the window into a scene so using them properly will improve your art and add impact to your designs Navigating the modo User Interface Modo offers visual cues that enable us to keep things straight from an orientation stand point In the bottom left corner of each viewport window a small axis indicator shows in the orthographic view the two axes making up the plane of view The colored lines point in the positive direction and the colors always correspond to a particular direction 7 CHAPTER 1 WORKING IN 3D red for x green for y and blue for z These same colors will appear in tool handles after modeling begins In the perspective view indicators are displayed for all three axes As in the orthographic view each line indicates the positive direction In the perspective view there is also a light gray square that aligns itself to the two
9. ations are much more capable of handling distance than those games were we want to keep draw distance in mind and create our scenes at or near actual scale In the bottom right corner of each modo viewport a display shows the scale of the small grid boxes By default the three orthographic views are linked together but the perspective view is independent Because modo uses physical scale for many aspects of lighting and texturing it is important to check your scale as you begin to create models in 3D space I have seen many students and regrettably myself create large sections of scenes only to realize that the pencil onscreen is as large as an oak tree or bigger In the 3D view you will also see a light colored grid that changes position and orientation based on your perspective This is the Work Plane and it is a huge help when you begin model ing objects Figure 1 6 is a breakdown of the modo user interface UI with labels for the features that are pertinent to this section MANEUVERING IN 3D SPACE 1 Orthographic Viewport 4 Navigation Widgets 2 Perspective Viewport 5 Scene Information Grid Size on Bottom 3 Axis Widget 6 Object Manipulation Transform Tools Maneuvering in 3D Space Now that you have a basic understanding of our canvas you are ready to start maneuver ing the viewports to get the best view for any part of the creative process In a 2D appli cation the view controls are simple and are limited to
10. axes that are most perpen dicular to the current view This square indicates the orientation of the work plane which is presented in more depth in Chapter 2 Creating Objects By staying aware of these markers we can more easily keep the scene aligned In addition to the axis widget the perspective view offers a gradient background that helps to keep us from looking at our scene upside down or enables us to more easily get there if that is our desire The background consists of a two color gradient a light blue gray color indicates up in the positive y direction think of the sky and a darker shade of the bluish color fills the negative y direction indicating the ground Because we spend a lot of time rotating around our objects to get the best view staying aware of this gradient ensures that we keep our feet on the ground so to speak Before you move on to navigating this space you need to know about scale You may notice that there are no document boundaries in 3D space as there are in a page layout document at least not visible ones What we do have to consider is the depth that the computer is able to re create This is called draw distance A good example of a short draw distance can be seen in older racing video games As you drive along a course and look into the distance objects such as buildings trees and mountains will appear rather suddenly instead of growing from small points on the horizon Although modern 3D applic
11. comes with rotation Rotation works based on the combination of two axes Consider the way we rotate in two dimensions With the x and y axes cover ing the screen horizontally and vertically we can rotate along the perpendicular axis in this case z Because only two axes are present we can rotate in only one dimension The addition of the third axis adds two more possible rotation options as we now have three planes to consider xy xz and yz As if this did not complicate things enough there is one more point to consider the center of rotation In a 2D layout we rotate relative to the center of the document If we were to rotate only in relation to the origin center of space we would be very limited in our access to the work area To move freely in a 3D workspace we need to rotate our viewport dynamically So there are three types of rotation to deal with e Around the view focal point e Ona virtual tripod e Rolling around the axis perpendicular to the perspective Figure 1 7 shows a model from the front Figure 1 8 shows that same object with the view rotated to show the depth of the model MANEUVERING IN 3D SPACE First let s look at the rotation based on the center This type of rotation is accessed by pressing the Alt Option key while clicking the left mouse button or by clicking and drag ging the rotation widget in the top right corner of the viewport As you drag up down left and right the view shifts around t
12. ctively then the third axis z extends off the screen toward the viewer see Figure 1 1 This works well for starters but let s take it a step further and look at space in terms of a map or other top down design In this case the plane defined by the x and z axes makes up the Cartesian plane More specifically the negative z axis is north and the negative x axis is west in relation to the middle of our workspace see Figure 1 2 The center of space called the origin will be the starting point for all of our design work unless we specifically need to work in a different area of the scene Even in this case it is often best to create an object at the origin and then move it to the desired location because this will enable you to work with symmetry easily locate objects and move the mesh layer which can then be reset or animated much more easily UNDERSTANDING 3D SPACE Luxology s modo and many other common 3D applications work by default with the y axis pointing up Some applications however use z as the up axis The modo program allows you to customize this aspect in its preferences Choose System gt Preferences gt Input gt Accuracy And Units From the heading marked Coordinate System you can change the up axis to z y or even x to suit your needs You can view a 3D scene through either an orthographic or a perspective view An orthographic view offers a completely flat vantage point of objects and placement
13. d pressing the Enter key on the Mac Tab or Enter will change the other values proportionally In other words if all fields read 100 for scale and you enter 10 in the X value the other two values will be changed to 10 automatically 14 CHAPTER 1 WORKING IN 3D First let s consider the Move tool When activated the tool handles appear at the center of the selection and show arrows that align to each axis x y and z and circles that float between the arrows in free space For reference the colors of the arrows corre spond to the axis of movement To move in a single axis click and drag on the individual arrows When the axis is active the arrow turns yellow Clicking and dragging anywhere but on the tool handles in the perspective view causes the handles to snap to the click point and dragging moves the object on the Work Plane Clicking and dragging on the circles moves the object perpendicular to the axis of the same color red green or blue for x y and z respectively While in the orthographic views clicking and dragging on the handles produces the same behavior as in the perspective view and clicking off the handles moves the object along the plane in view The hot key for the Move tool is W CENTERING THE TOOL HANDLES The default behavior of the tool handles to align to a click point is controlled by the Action Center which is set to Automatic when modo starts up cover Action Centers in depth in future chapters
14. he focal point This rotation technique keeps a set distance from the center of view and always faces that point in space until another focus is selected To rotate the view from a tripod press Alt Option and the right mouse button The tripod rotation works exactly like a real tripod the orientation of the view is changed but the position of the view remains constant This can be quite useful when working on large scenes or architectural interiors One thing to remember is that this option is specific to views from cameras and lights so the basic perspective view is not able to use tripod based rotation QUICK TURNTABLE Using the right mouse button to rotate in the perspective view enables the view to rotate on its own As soon as you release the button the view continues to spin with the speed based on the mouse speed when the button was released Moving slowly allows for slow and sub tle rotation while a quick flick of the mouse sends the view spinning rapidly There is a falloff of speed and then the view comes to rest This can also be done with the question mark key which gives a single revolution around the scene Figure 1 8 11 Perspective view of a model 12 CHAPTER 1 WORKING IN 3D Finally by holding Alt Option and using the middle mouse button or scroll wheel but ton the view can spin perpendicular to the viewport This can be useful if the current view is upside down and needs to be flipped over quick
15. in a raster image but this is not the case Because a vertex represents a single point in space it is infinitesimally small and therefore does not appear in a finished 3D render The fact that the vertex is the basic building block of the 3D creative process means that it is visible only when several are combined to create edges and polygons Edges make up the next level in the 3D food chain When two points are joined together an edge is created This edge now exists in one dimension and is still invisible to the finished rendering Once again this should not be confused with a line in a 2D image file For both edges and points it is better to consider a vector illustration without any line weight assigned Individual points and lines may appear on the page but they will not print unless some thickness is attached to these elements To see these elements you must have a combination of at least three of them points and edges which creates a polygon EXPLORING A 3D SCENE A simple triangle represents the polygon at its most basic level Three points with three edges connecting them creates a defined surface For the most part four sided polygons also known as quads will be the basis for your models The reason for this will become clear when modeling is discussed in the coming chapters but suffice it to say that many forms can be more easily defined by quads than by triangles By combining and blending together multiple polygons object
16. ith the viewport containing all three objects from an angle as seen in Figure 1 9 Try to duplicate the view shown in Figure 1 10 A few minutes practicing with a simple scene such as this will reduce frustration when you have a more complex scene and are still familiarizing yourself with the controls Moving Objects in 3D Space Now that we have discussed moving around you can begin to look at moving the objects that you create There are three methods for basic object manipulation move scale and rotate Each of these tools known as transform tools can be activated by clicking the cor responding button on the left side toward the top of the user interface or by using their hot keys Each transform tool has some quirks or additional features that will speed your workflow if you take advantage of them After a transform tool is activated a property tab appears in the bottom left corner The fields in this tab enable you to enter numeric values for each of the transform func tions as well as control of some additional options for each tool These values can be entered by clicking in the fields and entering a value by clicking on the arrows to increase or decrease the values by small increments or by clicking and dragging the arrows MANEUVERING IN 3D SPACE 13 Figure 1 9 Starting perspective Figure 1 10 Goal after navigating the perspective view If a value is entered in a numeric field holding the Ctrl Control key an
17. ly This is also useful when aligning a view that is slightly skewed and requires a minor rotation to see a level view of the scene The three movement tools work well when the view is focused on either your entire scene or a specific selection The A key is used to center on all visible items in the scene You can use the rotation tool to spin around your entire scene and press Shift A to focus on a selection By selecting the area you are interested in or working on you can center your perspective and rotate around the area in question Subsequent chapters cover selec tions in more depth but you can get started selecting by simply clicking and dragging across some surfaces polygons edges or points in your scene After you select some thing pressing Shift A will center your view on that selection Practice Navigating in Space Open the file Navigation_Practice 1xo from the included DVD Spend a few minutes moving around the scene The more you navigate the space the more comfortable it will become Start by moving around the objects generally and then choose various sections of the objects and manipulate the perspective until you get a good view of them See if you can get a side view showing all three objects aligned in the view Remember to utilize all of your newly learned navigation tools Rotate pan and zoom your view Use the A key and Shift A centering tools to center your view on an area of interest The practice file starts out w
18. ndo com mand but movement in the generic perspective view cannot be undone A common analogy is that if an Adobe Photoshop or other 2D graphic image is like a painting a 3D document is like a sculpture Two dimensional art forms digital and ana log use space form and color to create the finished image Depth and dimension are cre ated through color variation for simulation of light and shadow Three dimensional art adds volume to the mix which offers more concrete simulation of real light and shadow Because 3D provides added levels of realism you need to consider additional parts of the creative process in order to create compelling 3D art Exploring a 3D Scene The next things to consider when beginning to work in 3D are the individual pieces of a 3D scene and the steps in the creative process that will result in a finished project a model still image animation and so forth This space is filled with points edges and polygons that create the objects Materials and textures control the appearance of objects Lights add shading and highlights to the scene The camera provides the vantage point for the finished scene Let s look at each of these in more depth Points Edges and Polygons At the heart of any model that you will create are three basic elements points also called vertices edges and polygons Points represent a single location in space The initial impulse is often to think of these as being analogous to pixels
19. odo The downside of image textures is that they can become pixilated if they are not of a high enough resolution Mathematical textures known as procedural textures are free from resolution and have a fairly wide range of styles from simple grids and gradients to complex fractal algorithms These tex tures however cannot be edited directly so placement of detail is random These textures can be used to modulate any aspect of a material Color can be applied to add variation as well as to colorize reflections or transparent tints Other possibilities include changing the amount of reflection or transparency the shininess the translu cency or even adding the appearance of depth on a surface see Figure 1 3 5 6 CHAPTER 1 WORKING IN 3D Figure 1 3 A few examples of possible textures Lights There are two methods of adding light to your 3D scenes using computer representations of real lights standard lighting or casting light from the environment and textures in the scene radiosity The former is relatively easy to compute and delivers results more quickly The latter uses more complex computation and slows the finished image but results in lighting with more subtlety nuance and realism Figure 1 4 shows a simple scene with standard lighting and Figure 1 5 shows that same scene using radiosity Figure 1 4 Figure 1 5 A scene using standard 3D lights A scene using radiosity for lighting NAVIGATING THE MODO USER I
20. s take form SINGLE SIDED POLYGONS Polygons exist as two dimensional elements within the three dimensions of a scene The flat surfaces of polygons face in a single direction Just as the points are infinitesimally small so polygons are infinitely thin This means that they are invisible when viewed from the back Some thickness must be added in order to make the geometry appear from all angles Materials and Textures After polygons are created they must be assigned surface attributes to define their appearance A material contains the basic description of how light interacts with a sur face The key components of a material are color reflection transparency refraction absorption and emission of light A material creates these attributes at a very basic level that is defined by either a color or a percentage depending on the attribute Proper combination of these properties can create a wide variety of looks and styles To achieve something beyond the evenly distributed appearance of a basic material additional layers must be added Textures add additional detail to surfaces Textures are made from either rasterized 2D images or mathematical functions that display colors based on various inputs Images can be placed on the surface of 3D models and offer a high degree of customization You can place details exactly where you want them and edit them either by using an application such as Photoshop or by using texture painting inside of m
21. tive to switch tools and be able to scale or move in multiple or all directions at once The Transform tool comes in most handy when making quick adjustments to both movement and rota tion Mostly this comes down to a matter of personal preference Try the tools and see which ones make the most sense to you and allow you to work the most efficiently The hot key for the Transform tool is Y Tools in modo are sticky and will remain active until the tool is dropped A tool can be dropped by pressing the spacebar the Q key or the Esc key On subsequent presses the spacebar will switch modes between vertex edge and polygon The Esc key will with additional strokes clear out the tool pipe I cover these functions in the next few chapters but because the Q key is bound only to dropping a tool it is often the first choice for this function Transform tools applied in vertex edge or polygon mode will alter the position of geometry and cannot be reset with the exception of centering the selection by using the Center Selected tool under the transform tools on the left side of the screen Objects can be centered on any axis or combination of axes When transforming objects in Item mode the changes are logged under the properties for the mesh layer The Properties tab at the bottom right corner of the screen contains numeric fields for position scale and rotation After a change has been made it can be adjusted or reset in the numeric fields
22. ts This is useful when precise rotation is required The Scale tool changes the size of the selected object or objects The handles for the Scale tool are similar to those of the Move tool The Scale tool is visually differentiated MANEUVERING IN 3D SPACE 15 by the ends of the tool handles which are boxes instead of arrows Just as on the Move tool the handles scale in one direction and the circles scale in two directions one plane Clicking off the handles scales based on the work plane Because clicking in open space still scales the object independently it is usually preferable to use the planar circles and scale uniformly in two directions Unlike the Move tool the Scale tool has another behavior controlled by the cyan colored circle at its center This circle scales the object uniformly in all directions The hot key for the Scale tool is R The Transform tool is a combination of all three of the other transform tools Move Scale and Rotate The question you may ask is Why on earth would I use individual tools when the Transform tool does it all The answer is that it really doesn t do it all Although the tool does provide the basic function of the Move Rotate and Scale tools it lacks several key options The move portion of the Transform tool does not have pla nar handles The scale portion lacks both planar handles and the uniform scale option Because the tool has to act on one axis at a time it is often more produc

Wiley 3D for Graphic Designers

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