1. Introduction to 3D Art and Animation
Lesson C (week 4):
Introduction to Surfacing:
Lighting, Textures, and Mapping

2. Surfacing in 3D
LIGHTING adds believability and tangibility to our scenes by: (1) Grounding objects and characters with shadows and Ambient Occlusion,
(2) Unifying the scene with color and highlights, and
(3) Creating identifiable light sources.
TEXTURES add believability and tangibility by differentiating surfaces with varied reflectivity (Specularity, Bump, Transparency). Painted or photo-manipulated color is also appealing, but it is the reflectivity that creates a sense of reality.
Together we call this process SURFACING: the combination of textures and lighting to define how light reacts differently to each surface in a scene.

3. Lighting Considerations 1
Light can be used in a scene for:
Direct (actual light) or Indirect (bounce) illumination, to represent Primary and Secondary light sources, static or dynamic (animated) lights, colored light and shadows, choices in what is lit and what is not to create meaningful shapes/drama.
Light can be used to guide viewer attention, promote understanding of a space, or obscure a space to enhance tension.
Lighting sets the mood– bright and happy, cold and unkind, warm and gentle, dark and moody.

4. Lighting Considerations 2
Lighting transforms a collection of objects into a place and a moment in time.

5. Lighting Considerations 3
How are these SPACES DEFINED by their lighting: by what is and is not lit? What new shapes are formed by what is illuminated and what is in shadow? Consider this extreme example of sfumato by Frank Miller:

6. Lighting Considerations 4
Strong silhouettes– shapes that vary smooth and sharp edges, large and small volumes—against a bright background draws the viewer into the place and the moment.

7. Lighting Considerations 5
Lighting for Mood: How do Colors and shadow position choices contribute to the way a shot and a scene feels? How do layers of tone effect this emotional state? How do zones of color call our attention and create tension? NOTE: Color meanings are coded by culture.

8. Lighting Considerations 6
Lighting for Meaning: Use contrasting colors and brightness to create sides, to move from one state of being to another. Assassin’s Creed: From darkness (regular populace) to light (affluent society) Or, in this shooter: from fiery danger and destruction to the blue light of peace and escape.

9. Lighting Considerations 7
Create Vast Distances: Distant objects lose detail, saturation, and contrast, and color-shift (blue-shift on earth). Limit your palette: Strong 2-3 color choices, contrasting warm and cool tones, help to focus the emotional moment. High contrast between areas of lights and shadows can also enhance the impact.

10. Lighting Considerations 8
Direct Attention with high contrast: limited areas of light in a large area of dark. NOTE: night-time is not black: it is dark blue.

11. Lighting Considerations 9
3-point Lighting: A hierarchy of brightness, position, shadow
KEY: Main light, real source location, brightest, main color temp, shadows
FILL: Mid height, analogous temp, mid brightness
BACK: Complimentary color temp, opposite location,
Low brightness, no shadows. AKA Rim or Bounce Light.

12. Lighting Considerations 10
Develop color spaces with Direct and Indirect lighting. Direct Lighting is the clear and brightest light source. Indirect lighting is faking the bounced light through added Ambient lights or utilizing settings in Global Illumination and Final Gather.

13. Lighting Considerations 11
In film, Ambient Occlusion is where we make objects self-shadow, creating believable areas of darkness where objects touch. In games, we create Lightmaps with Baked Lighting and Ambient Occlusion on static objects, and create a network of Light Probes to bake lighting for dynamic (moving) objects.

14. Lighting Considerations 12
Note how this simple scene is altered by different light treatments.

15. Lighting Considerations 13
With post-processing (in After Effects or most game engines) you can combine multiple render passes for advanced physically based render effects (PBR).

16. Lighting Considerations 14
Reference movies to inform your lighting!

17. Lighting Considerations 15
Build spaces with high contrast lighting, deep but penetrable shadows, and zones of color for mood and meaning.

18. Lighting: Maya Light Types
Primary lighting types we will use in Maya (found in the Rendering Shelf, or in the Create menu): Directional Light: Imitates sunlight by creating parallel shadows. Spot Light: Imitates a local light source in a cone: Desk lamp, street lamp, flashlight, headlights. Point Light: Imitates local light source shining in all directions: a candle flame, an unshaded bulb, a magical glowing orb. Ambient Light: Adds light to a scene without creating a highlight. Not used as a light source, but instead to imitate bounce lighting. Good for spreading window-sunlight around the window frame. NOTE: To work with the Arnold Renderer, the Spot and Point lights typically need to have a much higher intensity, around 100

19. Lighting: Theory and Implementation
INTERIORS LIGHTING (two methods):
3-POINT LIGHTING for object display and room planning: A hierarchy of three lights arranged around the scene in triangles seen from above and a side).
Key Light: The primary light source, brightest [100%], main scene color, darkest shadows [70%]. Example: a ceiling lamp.
Fill Light: The secondary light source, middle brightness [70%], soft shadows[30%]. Examples: a computer screen, sunlight through a window.
Bounce Light: Ambient room light, dimmest brightness [40%], no shadows.
2-POINT LIGHTING FOR ROOMS: Put a spotlight at top pointing down for the Key light and a spotlight at the bottom pointing up for Bounce light, same parameters as above.
EXTERIOR LIGHTING (three methods):
Basic Lights: Use a Directional light for sunlight and a Point light (with shadows off) for upward light bounce.
Image Based Lighting (IBL): Projects an image on your scene with ambient occlusion:
Arnold Physical Sky: Accurate real-world skydome system, uses IBL:

20. Lighting: Theory and Implementation

21. Lighting: Theory and Implementation
3-Point Lighting can be used to stage a dramatic moment

22. Photoshop: Interface
Workspace: Created with each new file ([Ctrl]+[N]). For 3D texturing projects, files must be power-of-two square, typically 512x512 for smaller objects and 2048x2048 for characters. All textures must be 72ppi (pixels per inch) Tool Bar includes move and selection tools, brush and eraser, paint bucket and rubber stamp, pan and zoom tools, among others. Toward the bottom are currently active and secondary colors, which you can switch between by hitting [x]. Zoom: [z] and [alt]+[z], Pan:[spacebar] Undo/Redo: [Ctrl/Cmd]+[z] Undo Multiple: [Ctrl/Cmd]+[Alt]+[z] Layer Manager: Window > Layers. Create a new layer so you do not draw on the Background layer. Hide/Unhide a layer. Brush:[b] (In top Option bar, choose solid and turn on pen pressure). Eraser: [e] Capture Shape: [Ctrl]+ click a layer to create a selection the shape of its contents, create a new layer, and use PaintBucket to fill.

23. Photoshop: Photo Editing
Dull Photo:
Layer manager and Blending Modes
Marquee and Lasso selections
Duplicate layers and selections
Copy selection: [Alt]+ click and drag
Clear selection: [Ctrl/Cmd]+[d]
Flesh Monster:
Create a new file: 2048x2048, 72ppi
Selections, copying and pasting
Transforms [Ctrl/Cmd] +[t]
Rubber Stamp
Eraser, opacity settings
Paint bucket, dark background
Export as a PNG: YourName_Monster.png

24. Photoshop: Texture Painting
Painting only works well with a pen-pressure tool, like a Wacom tablet or Cintiq. If using a tablet, turn on pen pressure and keep the tablet parallel with the screen.
Brush [b] settings: solid shape (never soft!), pen pressure on. Choose opacity: 100 for full color, to blend colors.
Brush Size: [ [ ] and [ ] ]
Color Pick in brush mode: [Alt]+Left Click
Choose Colors: make a palette in an unused corner. Hue = color choice in vertical bar. In box change Value (shade, how light or dark) with height, Saturation (amount of color) with side to side.
Eraser [e] settings.
Start with big brush, create big color shapes, then refine to smaller and smaller details.

25. Photoshop: Textures for 3D Models 1
In this course Photoshop is the recommended tool for creating 2D texture maps for your 3D models. A simple way to do this for architecture is with Tiling textures: images intended to repeat across a surface, and so have the same pixels on the left as on the right, and/or on the top as one the bottom.

26. Photoshop: Textures for 3D Models 2
To texture characters and object we want a precision texture map which allows us to paint details on the object surface according to a UVW Unwrap. Here is an unwrapped character that has been textured with painted detail:

27. Photoshop: Textures for 3D Models 3
And here is an unwrapped character that has been textured with photograph-manipulated detail (a lot of scaled photo pieces and rubber stamping):

28. Maya Texturing: Main Terms
Texturing is a process of applying Texture Maps to a Shader network to build a Material, which displays on an object according to its UV Mapping. Texture Maps are PNG files created in Photoshop. These should always be square and sized power-of-two for efficient rendering: 512x512, 1024x1024, 2048x2048. A Shader is a collection of code in Maya’s Hypershade that determine how a surface reacts to light. Its list of Channels define Color detail, Specularity (highlight reflection), Bump (faked surface mesh detail, like metal dents or cloth seams/ weave/ small wrinkles), Transparency (faked holes in the surface– great for hair or torn cloth!) and more. Insert Texture maps into these Channels. Most Texture Maps (aside from Color map) are greyscale; the Shader Channels react to where the texture is dark or light. In a Specular map white reflects, black does not, and gray reflects a bit. In a Bump map, white pushes out and black pushes in. In a Transparency map, white is visible and black (or an empty background) is where you get a cut-out shape. The Material is the combination of a Shader and Texture Maps (along with any other nodes added to define how the surface will function). MiddleMouseDrag from the Hypershade to apply Material to an object and hit [6] to display it in the Viewport. UV Mapping an object sets the location of each part of the 3D surface in a 2D square. UVW = XYZ in 2D space. A full “Unwrap” of a model cuts it up and arranges it as flat UV Shells. This 2D Unwrap can then be exported as a JPEG and brought into Photoshop to guide painting. Today we will look at basic Planar and Cylindrical maps and the UV Editor. Mapping tools are found in the Modeling module > UV menu.

29. Maya Texturing: Saving & Moving Files
IMPORTANT: texture images are not stored in Maya. The Hypershade only stores POINTERS to the files on the hard drive. Therefore, it is critical that you bring the images you use in your scenes with you when you come to class.
The most effective way to manage texture image files in Maya is to create a folder on your computer in which to keep your Maya file with a sub-folder for your texture images. You must then go to the Maya File menu, hit Set Project, and navigate to this main Project Folder. Maya will create a Workplace file that will help it to always know where the texture files are located, making it easy to reconnect those textures when at a new computer.
[YourName] (your project folder)
|____> YourName_hw3_room.mb (your Maya file)
|____> [images] (your texture folder)
|_____> LinolumFloor.png
|_____> WoodTable.png
|_____> PlasterWall.png
To post this folder structure to Piazza, put it all in a.ZIP, so that only your screenshots and/or Playblast each week is outside of the zip for easy viewing.

30. Maya Texturing: The Hypershade
Windows > Rendering Editors > Hypershade, or click the “Blue Olive” on the middle bar above the shelves.
Top panel is your current Materials. The 3 Shaders you see there by default (Lambert1, ParticleCloud1, ShaderGlow1) are automatically added to any new object created, so please never change them.
Left panel is the Create menu, filled with Shader and other useful nodes. Use a Maya > Blinn to test basic color and reflectivity controls (used for exporting assets for games). For film projects use the Arnold AiStandardSurface shader.
Bottom Center is the Work area, where a Shader is visible as a network of nodes. A new Shader appears in both the Materials above and the work area, but disappears from the work area if you close and re-open the Hypershade. To get a Shader back in the work area for changes, RightClickHold on the Shader in Materials to choose “Graph Network.”
Right is the Material Viewer and Property Editor. A selected Shader or node will display their properties here. To add a Texture Map to a Shader Channel, select the Shader and in the Properties Editor click the checkered square next to the desired channel to open the “Create Render Node” list. Choose “File” (fourth down), and in the File node Properties hit the manila envelope next to Image Name to choose the texture map from your hard drive.
Apply a material to an object: MiddleMouseClickDrag it from Materials onto your object in the Viewport, and then hit [6] to view textures.

31. Maya Texturing: The Hypershade

32. Texturing Exercise
DOWNLOAD the provided color and grayscale images of Spider-Man.
SET UP SCENE: In Maya, create a polygon Plane. Add a Sphere, Box, and Cylinder, and arrange them around the space on the ground Plane.
TEXTURING:
Open Hypershade. Create panel > “Blinn” to make a new Shader.
Edit Parameters panel (right) find Color Channel for the selected Shader. Click the checkered cube and choose File node. With this new File node selected, click the manila envelope next to Image Name and choose your color Spider-Man file. Because the file has a transparent background, it gets added to Color and Opacity.
MiddleMouseDrag the Blinn shader from your top Material library to objects in your Viewport. Hit [6] to display texture in Viewport.
Remove the Color map: select the color file nodes and hit [Delete].
Add grayscale image to Bump and Specular Channels of your Blinn, and orbit around the Viewport to see how light reacts to each one. Lower strength in the bump node to 0.5.
Re-add color map to the Color Channel, to see them all together.
LIGHTING: Rendering shelf > Point light, Spotlight, and Directional light. Note how their shadows function in scene. Adjust intensity, color, shadow density /color, light position and angle to build a hierarchy.

33. Maya Texturing: Using Tiling Textures
TEXTURE TILING: An effective way to texture architectural spaces is to use tiling texture maps– images meant to repeat horizontally and/or vertically—to cover floors, walls, furniture, counters, etc.
A good tiling texture for a floor is one where the pattern (down to the pixels) on the left-side matches up with the right side, and the top with bottom . Consider a wood or linoleum pattern. In Photoshop the Filter > Other > Offset tool can be used to turn an image inside-out to fix tiling issues.
In Maya, to change how often an image repeats on a surface we go to the Hypershade and look at the node to the left of the File node holding the image. This is the place2dTexture node, which defines how that File node image displays on the surface. In the Edit Parameters panel increase the values of the two Repeat UV slots and the image will begin to tile.

34. Hypershade for Technical Artists
Extra Cool Note: while the Hypershade is primarily a texturing tool, it is also a very effective node-based programming tool. Technical Artists often use the Hypershade to create functionality that their film or game team needs in their production pipeline. From the book “MEL Scripting for Maya Animators” by Mark R. Wilkins and ‎Chris Kazmier: Maya “Utility Nodes” can be used by a Technical Artist to make a variety of functions. Because utility nodes are particularly suitable for shading networks, Maya's Hypershade editor provides tabs labeled “General Utilities,” “Switch Utilities,” and “Particle Utilities” that contain convenient buttons to access useful nodes. Advanced tutorial: Create Custom Hypershade Nodes:

35. Maya Texturing: UV Editing 1/2
UV > UV Editor is a 2D display showing the current UV mapping (2d texture space) on your selected object. Use to edit UVs or as a selection tool for modeling. When opened it comes with a UV Toolkit panel. The model is displayed in this 2D space as one or more UV Shells.
Components: RightClickHold to choose UVs, Edges, or Faces (NOT Vertices).
Transforms: W/E/R (move/rotate/scale, in Viewport). Only Transform UVs or Faces.
Select an entire UV Shell: Hit [w] and LeftDoubleClick a UV.
Display Texture: In the upper-right, toggle on/off the texture display or switch textures.
Cut a Seam: Select Edges to cut, and in the UV Toolkit panel click Cut and Sew > Cut.
Stitch a Seam: Select the Edge/s on the UV Shell you do NOT want to move (note the Edge/s on the other shell to be moved and sewed will also select automatically), click Cut and Sew > Stitch Together.
To mirror UVs: Modify > Flip.
To smooth out your UVs for a more even-distribution, select all UVs and open Tools > Smooth. Click and drag the Unfold button slowly/ incrementally to open the UVs. NOTE: Mirrored UVs must be flipped before they can be unfolded.

36. Maya Texturing: UV Editing 2/2

37. Maya Texturing: UV Mapping 1/2
UV MAPPING IN THE VIEWPORT (track the results in the UV Editor!): Select faces on the model and apply mapping tools to overwrite the UVs in the editor. UVs can be overwritten repeatedly.
UV > Planar Mapping > Option Box: Creates a flat projection on the selected surface, based on chosen axis. Once applied, hit the red T for UV transform gizmo to move/rotate/scale the map in the Viewport, changing the texture appearance on the surface. Hit actual W/E/R to bake-in the Mapping, and then adjust in UV Editor.
UV > Cylindrical Mapping: A cylindrical projection (like paper rolled around the form). Hit red T for UV transform gizmo to move/rotate/scale map. Hit W/E/R to bake-in the Mapping, and then adjust in UV Editor.

38. Maya Texturing: UV Mapping 2/2
Given this 2D image, we can project it on an object like the sphere below. On the left we have a Planar mapping, like projecting the image from a flat piece of paper. On the right is a Cylindrical mapping, like wrapping that paper into a tube around the mesh.

39. Apply lighting & Tiling Textures to Your Room!
AND REMEMBER: Texture Images are not stored in Maya, only pointers to them. You need to bring the whole folder structure with you, and File > Set Project.