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Sculpting, from Traditional to Digital One of the most exciting aspects of ZBrush is the way it allows the artist to interface directly with the model and create in a spontaneous and organic fashion, just as if working with balls of digital clay. Thousands of years of artistic tradition have given us a wealth of techniques when it comes to the discipline of sculpting.
2 chapter 1 ■ Sculpting, from Traditional to Digital Figure 1.1 Examples of traditional clay sculpture Figure 1.2 A selection of gesture sketches Gesture is the source of the life of a drawing or sculpture. It must be addressed from the outset—if the gesture is poor, it can be difficult to introduce it later into the process. If you start with a strong gesture, the sculpture will be appealing and alive from the start.
■ Gesture, Form, and Proportion 3 Figure 1.3 An example of gesture and action The rules of gesture apply to even a sculpture that is not a figure. Notice in the lion’s head how the gesture of the lines in the mane serve to create a sense of flowing action down toward the ring (Figure 1.5). These lines are more of a graphic consideration and can almost be considered in the abstract. Their presence serves to strengthen the visual impact. Closely linked to gesture is the concept of rhythm.
4 chapter 1 ■ Sculpting, from Traditional to Digital Gesture is an important consideration no matter what you may be sculpting. It is gesture that makes a sculpture exciting, whether it is a door knocker, a monster, or a human. Especially when dealing with figurative sculpture, a well-executed gesture with special attention to rhythm helps establish a sense of weight and balance in the figure. Form Figure 1.
■ Gesture, Form, and Proportion 5 It can be helpful when sculpting to remember that the shapes you are making with your brush will affect how light and shadow interact on the surface. That is how the shapes are created. If the light is turned off, all form goes away. Creating good form as you sculpt requires an understanding of both the shape itself as well as the quality of the shadows created by that shape under different lighting conditions.
6 chapter 1 ■ Sculpting, from Traditional to Digital Try to be sensitive to the transitions between your forms and the variation you create. If the transitions between all your shapes are the same hard-edged shadows, the figure will be visually bland. An important concept to bear in mind while you sculpt is to reduce everything to its base form and work on big shapes first. Just as a painter will tackle the big shadows and big lights first, then work down to details, the same is true in sculpting.
■ Gesture, Form, and Proportion 7 The viewer will have different reactions to a character based on the relationships between its basic forms. This relationship between forms is called proportion. The proportions between the basic forms have a visual impact on the viewer. The viewer’s reactions can change based on how the artist manipulates these relationships.
8 chapter 1 ■ Sculpting, from Traditional to Digital Subdivision Levels People often ask me how densely they should subdivide their model while working. The answer is never a set number. The subdivisions you can get on your machine will vary depending on how much RAM is installed. The polygon count of your level 1 mesh will also influence how densely you can subdivide.
■ ZBrush Interface General Overview 9 This tutorial is designed to introduce you to the sculpting brushes and some of their basic settings. We’ll also explore ZBrush’s 2.5D Illustration brushes and briefly discuss lighting and rendering within ZBrush. By completing an illustration in ZBrush, we’ll touch on each facet of the program and introduce tools and workflows that will be valuable as you progress through the book. We’ll delve into each menu in more depth as it becomes pertinent.
10 chapter 1 ■ Sculpting, from Traditional to Digital In the following example, from my sculpting the female figure tutorial on www.thegnomon workshop.com, I’ve drawn black lines over the form to represent the gesture. These long, flowing curves are what the forms were developed around and help give the sculpture character. I typically start by visualizing these curves on screen while I sculpt, then try to push and pull the forms to match them.
■ ZBrush Interface General Overview 11 Proportion plays a key role in defining the “character” of any design. The final image shows how enlarging the head on this sculpture affects the viewer’s impression of it. The design appears more childlike and seems to have a smaller overall stature. An important part of this exercise is to also be aware that none of the finite details were changed.
12 chapter 1 ■ Sculpting, from Traditional to Digital Flanking the document window are two columns that contain some quick links to other menus. The left side has fly-out icons linked to the Brush, Stroke, Alpha, Texture, and Material menus. Here you will also find a color picker for selecting colors while painting. The right side contains a selection of icons primarily concerned with navigating the document window and the display of your active tool.
■ ZBrush Interface General Overview 13 Table 1.1: ZBrush Menus Menu Description Alpha Options to import and manipulate alphas, grayscale images primarily used as brush shapes, stencils, and texture stamps. Brush Contains the 3D sculpting and painting tools. Color Options for selecting colors as well as filling models with color or material. Document Options for setting document window size as well as exporting images from ZBrush. Draw Settings that define how the brushes affect surfaces.
14 chapter 1 ■ Sculpting, from Traditional to Digital Table 1.1: ZBrush Menus (continued) Menu Description Zoom Shows an enlarged view of portions of the canvas. This menu is not often accessed other than to find the Zoom and AAHalf buttons to affect document display size. These buttons are usually available on the screen’s right menu. ZPlugin For accessing plug-ins loaded into ZBrush. Here you will find Decimation Master, Subtool Master, and other plug-ins that expand ZBrush’s functionality.
■ ZBrush Interface General Overview 15 Rotating is the simplest movement to accomplish. With the mouse off your model in the document window, notice that it becomes a circular arrow. Left-click and drag, and the model will rotate with your movements. If you right-click and drag while hovering your mouse over the object, the model will rotate. Note that if you tap the right mouse button, it will bring up the quick menu.
16 chapter 1 ■ Sculpting, from Traditional to Digital Rectangle and Circle will create selections by dragging a circular or rectangular shape. You’ll see Square and Center options in the Stroke menu as well. Square will cause the two strokes to create perfect circles or squares rather than ellipses or rectangles. Center will force the shape to generate from the center out. The Curve stroke type is used by the Mask Curve brush.
■ Using the ZBrush Tools 17 In ZBrush you can work with models, tools, or documents. For sculpting characters we’ll focus on tools and models. When creating final rendered images in ZBrush, we’ll make use of the Document settings. Creating a 2.5D Pixol Illustration ZBrush works with essentially three types of objects: models, ZTools, and documents.
18 chapter 1 ■ Sculpting, from Traditional to Digital Sculpting a Lion’s Head You will begin by sculpting the lion head. For the lion bas-relief we’ll use a ZBrush primitive, the Plane3D tool. I want to remind you that I am constantly moving the ZTool as I work, sculpting from all angles. You can see this in the video captures of the tutorial sessions provided on the DVD with this book. 1. Under Tool, click the active tool icon and select Plane3D.
■ Using the ZBrush Tools 19 At this time you may also turn on Perspective Camera. By default ZBrush uses an orthographic camera, but if you want a view that is more natural, click Draw → Persp to activate the perspective view. The focal angle can be adjusted with the Focal Angle slider. The Floor button will activate a floor grid that displays in the document window.
20 chapter 1 ■ Sculpting, from Traditional to Digital 8. While working, establish the forms that are advancing in space, like the snout and brows, as well as those that recede, such as the eye sockets and mouth. You can cut in with your brush by clicking the ZSub button at the top menu bar or by simply holding down the Alt key while you sculpt. 9. To quickly bring the faces of the snout forward and create depth in the head, in a threequarter view use the Move brush (Figure 1.23).
■ Using the ZBrush Tools 21 Figure 1.20 Shape roughed in from front and side Figure 1.21 Objects may look fine from the front while lacking depth when viewed from other angles. Figure 1.22 The flat face from top and corrected face from top Figure 1.23 Pulling the snout forward from the top and side views 572573c01.
22 chapter 1 ■ Sculpting, from Traditional to Digital Everyone uses the sculpting tools differently. You find the combination that works for you through experimentation and emulation. Sketching character heads or faces on primitive spheres and planes makes for great practice. You can quickly select brushes by using the built-in brush hotkeys. Press the B key to bring up the complete Brush menu. Next, press the first letter of the brush you want. For example, press M if you want Move.
■ Using the ZBrush Tools 23 is a primitive, we cannot sculpt but we can change the object’s parameters. In the case of the ring, we want to make it smaller. Select Tool → Initialize, and change the ring’s SRadius setting to 21 (Figure 1.26). 2. To make this ring ready for inclusion with the rest of the lion head, convert it to a polymesh. Click the Tool menu at the top of the screen and click the Make PolyMesh3D button. If you simply wanted to add Figure 1.
24 chapter 1 ■ Sculpting, from Traditional to Digital Drag to create line on surface Click and drag on line to move the transpose line Click and drag end circle to move line endpoint Figure 1.28 Using the Transpose tool 4. Enter Transpose mode by pressing W. You will now have a transpose line on the screen. Click on the 3D ring and drag to a point on the canvas to draw a new transpose line (Figure 1.29). Because we are in Move mode at the top of the screen, this will allow us to move the ring.
■ Using the ZBrush Tools 25 Moving in ZBrush “Moving” in ZBrush can refer to moving ZTools in relation to each other, moving in relation to the canvas, or moving polygons as a group with a brush. There are three methods of moving inside ZBrush: Transpose Designed for posing models or moving subtools in relation to one another. Move Brush Moves polys and faces with a brush when sculpting large forms. It is used to move parts of a model to changes its shape.
26 chapter 1 ■ Sculpting, from Traditional to Digital If you set the Brush slider to -60, the inverse happens: it presses in while it pinches. I keep the slider at 60 and use the Alt key to invert my stroke to press in when needed. 2. You can further control the sweep and smoothness in the strokes of the mane by using the LazyMouse option. This technique will average the stroke and help you create a sweeping line. Press the L hotkey or select Stroke → LazyMouse (Figure 1.33).
■ Using the ZBrush Tools 27 4. Select the Move brush from the brush palette and tumble to a side view. Adjust your draw size and pull the lower jaw up and around the ring (Figure 1.35). If the Move tool isn’t working strong enough, raise your ZIntensity slider to increase its power. You may also want to turn on subtool transparency with the Transp button at the right side of the screen.
28 chapter 1 ■ Sculpting, from Traditional to Digital You can mask out areas you don’t want to affect with your strokes by pressing the Ctrl key. Your cursor turns yellow to let you know you are in Masking mode. To paint out part of a mask, use Ctrl+Alt-click. To mask large areas, Ctrl-click outside the model and drag a masking rectangle. Also experiment with the Lasso tool for making more specific and complex mask selections. Select Mask Lasso from the Brush menu.
■ Using the ZBrush Tools 29 11. With the Pinch brush and LazyMouse on, pinch the outer edge of the eyelid (Figure 1.41). Be sure to reduce your draw size. At this stage, I also pinch in using the Alt key to add some subtle wrinkles around the upper eyelid and indicate the furrow at the bottom of the eye where the sphere of the eyeball dips into the skull. 12. Pinch the inner edge closest to the eyeball (Figure 1.42). Hold down Alt to pinch in instead of out.
30 chapter 1 ■ Sculpting, from Traditional to Digital Finishing Your Model The following list represents some of the edits made to this sculpture to bring it to completion: • Added the tear duct to the eyes. These little details are extremely important, even on a stylized eye such as this. • Raised the ears higher on the head to give a more feline appearance. • Increased the slope in toward the jaw and pulled the side curls out at an angle.
■ Using the ZBrush Tools 31 These techniques are useful to the digital illustrator as well as when conceptualizing a character with ZBrush. Even though you can export your work to external renderers for animation and rendering, I wanted to show the power of ZBrush as a rendering and illustration tool in itself. These are often overlooked aspects of the program, but they are powerful tools to have in your arsenal even if you never do 2.5D illustration.
