Applying D Textures and Projections
The 3D Placement utilities generated by 3D and environment textures possess unique application traits. Projection utilities, on the other hand, are designed to work with 2D textures. Three-dimensional textures procedurally create a wide range of solid patterns that is, they have height, width, and depth. In addition, you can convert 3D textures into 2D bitmaps with the Convert To File Texture tool. Review and application of 3D textures Attributes of 2D and 3D noise textures Application of 2D...
Preparing Polygons
Although NuRBs surfaces are ready to render with their default uvs, polygon surfaces often need a great deal of adjustment. The use of primitives is the exception since the primitive's inherent uvs are orderly. As soon as various polygon modeling tools are applied to a primitive, however, the resulting uv texture space is cluttered and unusable see Figure 9.8 . Figure 9.8 A polygon cylinder's default UV texture space and the result of numerous modeling tools Figure 9.8 A polygon cylinder's...
StepbyStep Creating the Cover Illustration
The cover illustration was created specifically for this book. Since the amount of time available to create the render was limited, I combined standard lighting and texturing techniques with various shortcuts. The model of the woman, known as Masha, was built by Andrey Kravchenko and is commercially available via www.turbosquid.com. Masha's polygon count, including clothing, is approximately 45,000 triangles. For purposes of the illustration, however, modeling adjustments were made to the face....
StepbyStep Splitting Up a Render
Professional animators tend to split their renders into layers in order to make their animation projects more efficient. Not only does this habit increase the speed of individual frames, it also ensures that revisions are more easily undertaken. In addition, renders split into layers are more easily manipulated in the compositing process. Maya provides the Display Layer and Render Layer editors to help automate such a process. Detailed instructions for using these editors are included in...
Chapter Tutorial Preparing the UVs of a Polygon Model
In this tutorial, you will prepare the UVs of a polygon model, as shown in Figure 9.34. Open piggy_uv.ma from the Chapter 9 scene folder on the CD. This file contains a polygon model whose uvs are unusable as is. Select the entire surface, switch to the Polygons menu set, and choose Create UVs gt Cylindrical Mapping with default options. While the projection manipulator is visible, go to the Channel Box. Change the polyCylProjl Rotate X value to 270. This orients the projection to the length of...
Organizing the Render
Rendering is the final step of the animation process, yet it requires the same attention to detail as any other aspect of 3D to be successful. Creating clean scene files and establishing appropriate paths to bitmaps are important steps. The speed of any given Maya render depends on the quality of the scene file. If a scene file contains unnecessary construction history, broken nodes, and unneeded geometry, the render will suffer. A quick solution to this problem is to choose File gt Optimize...
Applying Motion Blur
Motion blur is a streaking of objects in motion as captured by motion picture, film, or video mediums. The effect is an artifact of the time required to chemically expose film stock or electronically process light through a video CCD chip. If an object moves 1 foot during the 1 60 of a second required by a camera to create one frame, the motion blur appears 1 foot in length on that frame. Motion blur is also perceived by the human eye when the motion is rapid. Although the human brain processes...
Understanding Depth Maps
when the use depth Map Shadows attribute is checked for a spot, directional, point, area, or volume light, Maya creates a temporary depth map see Figure 3.1 . Figure 3.1 The Depth Map Shadow Attributes section of a spot light's Attribute Editor tab Figure 3.1 The Depth Map Shadow Attributes section of a spot light's Attribute Editor tab The depth map represents the distance between surfaces in the scene and the shadow-casting light from the light's point-of-view. this information is stored as a...
Chapter Tutorial Building a Custom Cartoon Shading Network
In this tutorial, you will create a custom cartoon shading network that combines solid colors with a simulated halftone print see Figure 7.21 . Sampler Info, Surface Luminance, Condition, and Multiply Divide utilities will be used. Figure 7.21 A custom cartoon shading network applied to primitives. A QuickTime movie is included on the CD as cartoon.mov. Figure 7.21 A custom cartoon shading network applied to primitives. A QuickTime movie is included on the CD as cartoon.mov. 1. Create a new...
Solving Light Gap Errors
Light gaps, which look like thin, bright lines, often appear along the intersection of two surfaces. For example, in Figure 3.16 two primitive planes sit at a right angle and intersect slightly. A spot light, placed behind the surfaces, casts a default depth map shadow. A light gap appears along the intersection seam. Such gaps are due to a mismatch of the depth map to the render of the geometry. Depth maps do not receive anti-aliasing, which leads to stair-stepping. See Chapter 10 for...
Math Utilities
The values provided by various attributes in Maya are often unusable in a custom shading network. The numbers are too large, too small, or negative when they need to be positive. Hence, Maya provides a host of math utilities designed to massage values into a usable form. The utilities vary from simple Reverse, Multiply Divide, and Plus Minus Average to advanced Array Mapper, Vector Product, and others . Switch utilities, on the other hand, provide the means to texture large groups of objects...
Using Point Lighting 1
The 2-point lighting scheme matches many of the lighting scenarios we encounter in our everyday lives. The scheme often involves a strong key and an extremely diffuse fill. The following are examples of 2-point lighting Sunlight streams through a window. The light bounce from the interior walls serves as a fill. Office workers sit in a windowless room lit with overhead fluorescent lights. The light bounce from the walls, desks, and floor serves as a fill. A couple walks down a sidewalk on a...
Harnessing the Power of Math Utilities
Math utilities refine outputs and emulate complex mathematics. Switch utilities let you create numerous texture variations with a single material. With Array Mapper and Particle Sampler utilities, you can control a particle's material and movement on a per-particle basis. You can also create unique effects with Stencil and Optical FX utilities. Practical applications of each math utility A general approach to using per-particles attributes The functionality of the Array Mapper and Particle...
Rendering the Cornell Box with Maya Software
You can replicate indirect lighting and the mental ray Global Illumination system with Maya volume and ambient lights. Although the result is not perfect, the render is often close enough to meet the aesthetic demand of a project that is on a tight deadline. For example, in Figure 12.32 the Cornell Box is rendered with the maya Software renderer with Raytracing checked. The overall lighting is similar to the one rendered with global illumination and Final gather see Figure 12.31 . To achieve...
Shadowing with Light Fog
Light Fog supports depth map shadows with the Maya Software renderer. More important, light Fog will fail to interact properly with objects in a scene unless use Depth Map Shadows is checked. unfortunately, raytrace shadows and the mental ray renderer will not work with Light Fog. However, several mental ray shaders produce their own volume fog. For more information, see Chapter 12. Two additional fog attributes, Fog Shadow Intensity and Fog Shadow Samples, are included in the depth Map Shadow...
Mastering the Blinn Material
You can adjust a Blinn material to emulate a wide range of surfaces. In this section, steps for achieving wood, metal, and plastic using common map attributes are detailed. To simplify the demonstration, a single bitmap texture, rusty.tif, is used in each case see Figure 4.30 . For details on creating glass, water, and ice, see Chapter 11. Figure 4.30 A noisy, dirty, rusty bitmap texture that can be applied in numerous ways. This bitmap is included on the CD as rusty.tif. Figure 4.30 A noisy,...
Using the D Paint Tool
With the 3D Paint tool, you can paint texture maps in a workspace view with a vir-z tual paint brush. In addition, you can rough in bitmaps in preparation for painting the final texture map in Photoshop or other paint program. s Since the steps required by the 3D Paint tool are fairly esoteric, the following guide is 1. Select a NURBS, polygon, or subdivision surface. Polygon and subdivision sur- g faces must have nonoverlapping UVs that fit within a normalized UV range of 0 to 1. Assign a new...
Bump and Displacement Mapping
Bump and displacement mapping can add an extra level of detail to any material. Each has its own unique strengths, weaknesses, and application. Although the Maya Displacement Shader can be difficult to adjust, the Height Field utility provides a rough preview in a workspace view. Bump maps perturb normals along the interior of a surface at the point of render. They do not, however, affect the outer edges. Nevertheless, the bump effect can easily sell the idea that a surface is rough. When you...
Clamping Values
The Clamp utility is designed to keep a value within a particular range. If a value is too low or too high, it clamps it. As an example, Table 6.2 shows what happens to inputR values if MinR is set to 0.3 and MaxR is set to 1.0. Table 6.2 Clamped Output Values Resulting from Different Input Values B In this example, if the inputR value is less than 0.3, the outputR value is 0.3. If inputR is greater than 1.0, outputR is 1.0. If inputR is between 0.3 and 1.0, out- 3 putR is the same value. The...
Redirecting the Initial Shading Group Node
By default, Maya assigns all new geometry to the Initial Shading Group and the Lambert material connected to it named lambert1 . You can replace the lambert with a Blinn or any other material by deleting the connection between the outcolor of the default lambert material node and the surfaceShader attribute of the initialShading-Group node. You can locate the initialShadingGroup node by clicking the Input And output connections button while lambert1 is selected. You can then connect the...
Chapter Tutorial Creating Caustics with Final Gather
In this section, you will light and render a still life with Final Gather. You will also create a reflective caustic on one of the walls see Figure 12.34 . Open sun_box.ma from the Chapter 12 scene folder on the CD. The scene features a variation of the Cornell Box with three walls and skylight hole. In this exercise, all the walls are gray. The floating sun symbol will become reflective metal. Create a spot light and place it directly above the skylight opening. Point the light down so it's...
Reviewing D Textures
Maya 2D textures can be grouped into the following categories cloth, water, perlin noise, ramp, bitmap, and square. Aside from bitmaps, all these textures are generated procedurally. That is, Maya creates these textures with specialized algorithms that create repeating patterns. the Cloth texture is unique in that it generates interlaced fibers. Aside from obvious use in clothing, it can be adjusted to generate various organic patterns such as reptile scales. For example, in Figure 4.18 a Cloth...
Determining Critical Project Settings
Aspect ratios, frame rates, and film backs are important elements of any animation project and should therefore be selected early in the production process. Although you can change the aspect ratio at any time, such a change can lead to poor compositions. Selecting a different film back midway through a project can also lead to drastic composition changes and interfere with live-action plate matching. Switching frame rates can lead to improperly timed motion and broken lip sync. camera focal...
Mastering the Hypershade Window
The Hypershade window is the heir to the Multilister domain. Although the Multil-ister window is a legacy tool from powerAnimator, the Hypershade was created specifically for maya. Everything that can be done in the multilister can be done in the Hypershade, but not vice versa. You can access the Hypershade by choosing Window gt Rendering editors gt Hypershade. You can access the multilister by choosing Window gt Rendering editors gt multilister. the Hypershade window allows the connection of...
Using Dielectricmaterial
The Dielectric_material shader re-creates a material that is a poor conductor of electricity. Real-world dielectric materials include ceramics, plastics, glass, and some liquids, such as water. In addition, the Dielectric_material shader replicates the interaction between photons and dielectric material boundaries known as interfaces . Based on angles of incidence and refractive indices of the involved interface materials, a photon will either transmit refract through the second material or...
System Requirements
Make sure that your computer meets the minimum system requirements shown in the following list. If your computer doesn't match up to most of these requirements, you may have problems using the files on the companion CD. For the latest and greatest information, please refer to the ReadMe file located at the root of the CD. A PC running a valid license of Autodesk Maya 8.5 or higher. Maya 8.5 requires one of the following operating systems 32-bit Microsoft Windows XP SP2 or higher , 64-bit...
Common Light Attributes
The following attributes are common to all Maya lights Color Sets the color of the light. if you map a texture to this attribute, the result is simi- lar to a slide projector and the texture appears on the surfaces that the light strikes. h You can emulate the shadow of an object that does not exist by mapping a black-and- white texture to the Color attribute. For example, in Figure 2.1 a bitmap featuring J black leaves on a white background is mapped to a spot light, which creates a simu...
Mastering the Render Settings Window
The majority of Render Settings window attributes are intuitive and easy to use. However, several of them are worth a closer look. The attributes are divided into Common and renderer-specific tabs. The Common tab includes Frame Padding, Alpha Channel Mask , Depth Channel Z Depth , Resolution, Resolution Units, Device Aspect Ratio, and Pixel Aspect Ratio attributes see Figure 10.8 . File name prefix not set using scene name Alpha channel Mask. r Depth channel Z depth Device aspect ratio Pixel...
Reading Surface Luminance
During a render, the Surface Luminance utility automatically reads the luminance of every single rendered point on the surface assigned to a material that is part of the same shading network. That is, the utility can determine the total amount of light a point on a polygon face receives and outputs a value from 0 to 1 that represents this. As an example, in Figure 6.28, a custom crosshatch material is applied to a medallion model. The crosshatch pattern is generated by a Ramp texture and a sur-...
Managing Renders with the Render Layer Editor
Render management is an inescapable part of animation production. complex projects can easily generate hundreds, if not thousands, of rendered images. The complexity is magnified when objects are rendered in separate passes or when shading components are addressed individually. Fortunately, Maya's render Layer Editor makes the task more efficient. The Layer editor is accessible by clicking the show The channel Box And Layer editor icon on the status bar. The Layer Editor is composed of two...
Adjusting Final Gather Attributes
For the Final Gather system to work, the Raytracing and Final Gathering attributes must be checked in the Secondary Effects subsection of the rendering Features section of the mental ray tab. In addition, Final gather has a number of unique attributes in the Final gathering section see Figure 12.24 . P Final Gathei rng Accuracy p F'oiri Density 11.000 I- Enable Map VisuaSzer I Preview Final Gather Ties Cp rr c for Animations I- Use Radius Quality Control V Precompute Photon Lookup Filler...
Using Irradiance
o Final Gather does not require lights to render a scene. The system can use irradiance z alone. Technically speaking, irradiance is a measure of the rate of flow of electromag- z netic energy, such as light, from a per-unit area of a surface. The Ambient Color and Incandescence attributes of standard Maya materials represent irradiance. g For example, in Figure 12.25 a scene is rendered with Final Gather. The Enable Default Light attribute is unchecked in the Render Options section of the...
Using Esoteric Utilities and Scene Nodes
Several utilities and nodes fail to fit into a specific category. Of these, the Stencil utility provides an alternative method of blending maps together. You can repurpose Optical FX and Unit Conversion utilities to fit a custom network. Although scene nodes those automatically generated by Maya are not particularly flexible, they provide critical services in a 3D scene. As stencil is the third texture application radio button listed in the 2D Textures section of the Create Maya Nodes menu...
Exploring D Textures
Maya 3D textures are procedural. That is, they are generated mathematically through predefined algorithms. Procedural textures are resolution independent and do not have defined edges or borders. Many of the algorithms employed by Maya make use of fractal math, which defines nonregular geometric shapes that have the same degree of nonregularity at all scales. Thus, Maya 3D textures are suitable for many shading scenarios found in the natural world. For example, the addition of 3D textures to a...
Controlling mental ray Shadows
Shadows created by mental ray are defined in two areas the Shadows section of the mental ray tab in the Render Settings window and the shadow-specific sections of each light's Attribute Editor tab. A light's Use Ray Trace Shadows attribute functions in the same manner for the mental ray renderer as it does for the Maya Software renderer. Maya Software shadows are discussed in Chapter 3. However, mental ray supplies separate attributes in the Shadows section of the mental ray tab in the Render...
Rule of Thirds
The rule of thirds is a compositional technique developed for modern photography and videography. Simply put, you can take any frame and divide it into three horizontal and vertical sections to determine the alignment of subjects see Figure 1.37 . For example, you can align a tree, a person, or other vertical element with a vertical line. You can align the horizon or a building with a horizontal line. The four points at which the lines cross are considered prime compositional spots and should...
Shadowing with nCloth
with nCloth, Maya provides a robust dynamic simulation system with which you can realistically emulate cloth objects. nCloth adapts preexisting polygon surfaces. To create a simple scene with nCloth, follow these steps 1. Create a polygon plane and position it above a polygon sphere. 2. Switch to the nCloth menu set you must be running Maya Unlimited . Select the plane and choose nCloth gt Create nCloth. The plane is tessellated and converted into an nCloth dynamic mesh. This is indicated by a...
Checking Color Calibration
Maya operates in RGB color space. Color space represents all the colors that a device can produce. The color space available to various output devices varies greatly. For example, the color space that a television can display is significantly different from the color space available to a computer monitor or a printer. Never assume that a computer monitor is displaying your renders correctly. If you are creating an animation for video, it's best to check the resulting edit on a professional...
Using mental ray Motion Blur
Two forms of motion blur are employed by the mental ray renderer No Deformation and FuII respectively named linear and exact in previous versions . No deformation motion blur is equivalent to Maya Software's 2d motion blur, in that it is unable to accurately portray rapid changes in direction or surface deformation. full motion blur, on the other hand, plots the motion vectors of each surface vertex and is thus sensitive to deformation. Unfortunately, FuII motion blur handles rapid changes in...
Creating Textures with the Transfer Maps Tool
The Transfer Maps tool can create normal maps and displacement maps by comparing surfaces. In addition, the tool can bake lighting and texturing information. e Although normal maps are related to bump maps, there are significant differences H Bump maps store scalar values designed to perturb surface normal vectors on a A per-pixel basis. In contrast, normal maps store pre-calculated normal vectors as S RGB values normal maps pay no heed to the surface normal vectors provided X by the surface,...
Using Lens Shaders
The mental ray renderer provides several lens shaders that affect the way in which light travels through the virtual camera lens. For example, Mia_lens_bokeh creates mental ray depth-of-field see Figure 12.18 . Bokeh is a photographic term that refers to the out-of-focus quality of an image. Figure 12.18 Depth-of-field is provided by the Mia_lens_bokeh shader. This scene is included on the CD as menta1_dof.ma. To use this shader with Maya 2008, follow these steps 1. Open the Attribute Editor...
Switching Outputs
switch utilities provide multiple outputs from a single node. That is, they switch between different values in order to create different results among the geometry assigned to their shading network. since the application of a switch utility is unique in Maya, a step-by-step guide for a Triple switch utility follows 1. Choose an RGB attribute of a material, such as Color, and click its checkered Map button. Choose a Triple switch from the switch Utilities section in the Utilities tab of the...
Selecting a Film Back
In Maya, a camera's virtual optical properties are defined in the Film Back section of the camera's Attribute Editor tab see Figure 10.3 . The most important attribute in this section is Film Gate. With a real-world motion picture camera, a film gate is T a plate with a rectangular opening that sits behind the lens and in front of the film M stock. The gate controls the exposure of the film by allowing only one frame at a time II to be struck by light. Commonly used cameras have distinct lens...
Raytracing with mental ray
By default, the mental ray renderer operates in scanline mode. Raytracing is only employed if it is activated as a secondary effect. Since many mental ray attributes are unique or at least different in name it is worth examining some common settings in the Render Settings window. As part of this review, mental ray motion blur and shadows are detailed. Mastering mental ray Quality Settings The mental ray Quality Presets attribute, found in the mental ray tab of the Render Settings window,...
Shifting Colors
twelve utility nodes in Maya are designed to shift colors. these utilities can convert color space, remap color ranges, adjust brightness and contrast, and even read the luminance of a surface within a scene. the Rgb To Hsv utility converts a Red Green Blue vector into a Hue saturation Value vector. the Hsv To rgb utility does the opposite. in maya, red, green, and Blue channels have a numeric range of 0 to 1. in HsV color space, Hue corresponds to a pure color and has a range of 0 to 360....
Raytracing with Maya Software and mental ray
Reflections, refractions, and chromatic aberrations are important qualities of materials such as water and glass. The Maya Software and mental ray renderers can provide these qualities through the raytracing process. Although the two renderers share many attributes, mental ray offers many advanced features. In particular, mental ray provides greater flexibility when rendering shadows and motion blur. Raytracing with the Maya Software renderer Creating reflections, refractions, and chromatic...
Color Theory Overview
In the traditional color theory model, red, yellow, and blue are considered primary colors. As such, they follow these rules No combination of any two primary colors can produce a third primary color. Combinations of all three primaries can produce a wider range of colors than any other combination of colors. You can form secondary colors by mixing together primary colors, which produces orange, green, and violet purple . You can form tertiary colors by mixing primary colors and secondary...
Adding Subtracting and Averaging Values
The Plus Minus Average utility supports addition, subtraction, and average operations. It operates on single, double, and vector input attributes. If single attributes are connected, they are not visible in the Plus Minus average utility's attribute Editor tab. However, double and vector attributes are indicated by input fields see Figure 8.3 . Figure 8.3 A Plus Minus Average utility with single, double, and vector inputs Figure 8.3 A Plus Minus Average utility with single, double, and vector...
Shadowing with Maya Hair
The Maya Hair system generates a series of dynamic curves that can simulate hair, ropes, chains, and other thin but long elements. The quickest way to generate hair in Maya is to switch to the Dynamics menu set, choose Hair gt Get Hair Example, select a hair icon in the Visor window, right-click, and choose Import Maya File name of hair file from the shortcut menu. A complete scene with a polygon model and hair system is brought in. Otherwise, you can create a hair system from scratch following...
Creating Reflections and Refractions with mental ray
By default, mental ray's Ray Tracing attribute is checked. The Ray Tracing attribute is listed twice in the mental ray tab once in the Rendering Features section and once in the Raytracing section see Figure 11.20 . The two check boxes are linked. Figure 11.20 The Raytracing section of the mental ray tab in the Render Settings window Figure 11.20 The Raytracing section of the mental ray tab in the Render Settings window The following attributes, found in the Raytracing section, control the rays...