3D in Photoshop
This section of the chapter covers the important tools and options that Photoshop uses to create and manipulate 3D content, including models imported from other applications. While this is not an exhaustive discussion of how every feature works, we hope to provide you with a good foundation for experimenting with these new creative options.
Basic 3D Tools
Photoshop provides several new tools for working with 3D content. They are broken into two groups: 3D tools and 3D camera tools.
Moving 3D objects. The 3D tools are designed for moving 3D objects across the canvas in different ways (Figure 9.6). This group includes 3D Rotate, 3D Roll, 3D Pan/Drag, 3D Slide, and 3D Scale. For the most part, these do what their names suggest: The 3D Rotate tool allows you to freely rotate an object around its own X and Y axes; the 3D Roll tool rotates the object about an axis that is parallel to the screen; the 3D Pan tool moves the object along its X and Y axes only; the 3D Slide tool lets you move the object along its X or Z axis; and the 3D Scale tool changes the object’s size without relocating it.
Figure 9.6 Photoshop’s 3D tools allow you to manipulate your 3D content on the document canvas.
To use one of the 3D tools, select it, and then click and drag on the canvas near your 3D object (be it a shape layer, mesh, or model) to perform the desired action. When a layer with 3D content is active and any of the 3D tools are selected, the options bar provides additional settings for modifying the individual X, Y, and Z axis values for each tool (Figure 9.7). These allow you to precisely position your 3D object relative to the background image or document grid, based on the type of movement the tool provides. When you move an object around with the different tools, this is called a custom position.
Figure 9.7 Photoshop’s 3D tool options, as seen from the Options bar
You can save any custom position by clicking the disk icon and saving it as you would any other preset. You can also choose a preset position (such as Left, Right, Top, or Bottom) from the pop-up menu. The house-like icon, Return to Initial Object Position, resets your object position to wherever it was when the document was last saved.
Keep in mind that the object tools move the actual model around the canvas (relative to the document grid), while the positions of the lights and cameras remain static. This means that shadows, light intensity, and a few other characteristics can change as the object is moved in different directions. For this reason, even if you think you have your lights set up just right, moving your 3D object around on the canvas may require you to make additional changes to lighting afterward (Figure 9.8).
Figure 9.8 Moving a 3D object changes its position relative to lights and other scene elements, and thus can affect the object’s appearance.
Moving cameras. The 3D camera tools provide options mostly identical to the 3D tools but cause only the camera to move around your 3D object, giving the appearance that the entire scene has shifted position, even though nothing but the camera has moved (Figure 9.9).
Figure 9.9 The Photoshop 3D Camera tools
Turn on the Ground Plane option in the 3D panel pop-up menu (discussed in the next section), and the difference between each of the corresponding tools’ effects on the document becomes obvious. For example, using the 3D Rotate tool and the 3D Camera Rotate tool may appear at first to have the same effect, until you activate the Ground Plane visibility. Then you see that when using the camera tools, all 3D objects and lights retain their positions relative to one another and to the document grid as the camera moves around them. You can use the 3D camera tools when everything is positioned properly on the document but you want to see what the scene looks like from new angles.
One 3D camera tool doesn’t have an equivalent—the 3D Zoom tool. It behaves similarly to a zoom lens on your DSLR. You can zoom in or out on a 3D object, which has the same effect as scaling, but the lighting and other scene elements are retained. Figure 9.10 shows the difference between zooming in on an object and scaling the object so that it fills the identical amount of frame.
Figure 9.10 The 3D Zoom tool controls the camera like a zoom lens on your DSLR. Zooming in will appear to make the object larger, though there is no effect on lighting or other material interactions.
Using the 3D camera tools, you can also employ extra settings in the options bar that are nearly identical to the ones discussed in the 3D tools section. You can independently set X, Y, and Z axis values for each camera tool to create a custom view, use the pop-up menu for view presets, return your camera to its original position, or save the custom position as a new camera view preset.
The 3D Panel
The main hub for working with 3D content in Photoshop is the new 3D panel. Figure 9.11 shows the default view for the panel, which filters all the 3D content in a layer as parts of a scene. Though nothing is actually being filtered in the default view, it’s important to understand that each of the view types is considered a filtered view. The 3D panel allows you to modify multiple properties of your 3D objects, including light settings, the colors and material properties of any surface on your 3D object, and the positions of your meshes.
Figure 9.11 The new 3D panel in Photoshop is where most creative 3D edits are applied.
Filter by: Whole Scene. The Filter by: Whole Scene view shows the entire stack of elements that makes up your 3D layer or model. Though it refers to the “whole scene,” it shows only those elements from the current layer. Other 3D layers do not appear unless they are selected in the Layers panel. It is possible to combine several 3D objects into the same layer if you need to, using the layer merge features in Photoshop. Although this filter mode works well for simple models or shapes, we generally recommend using the individual filter modes described later in this section to target specific portions of the model or 3D shape more quickly.
Filter by: Meshes. The tools provided in the Filter by: Meshes view work according to the same principles as the 3D tools described earlier and are used to position and rotate the individual meshes (polygons) that make up your Photoshop-generated 3D shape (Figure 9.12). When working with models created in other programs, Photoshop treats the entire object as a single mesh, rather than as a collection of mesh objects. You can also set whether the mesh catches and casts shadows, which can be important when integrating a model or 3D shape with other elements in your scene.
Figure 9.12 The Filter by: Meshes view in the 3D panel offers tools for positioning and rotating the meshes in your 3D shapes or your imported model. It also allows you to define whether your object will catch or cast shadows.
Filter by: Materials. The Filter by: Materials view gives you tools for creating and adjusting surface textures (Figure 9.13). If you have generated a 3D shape in Photoshop, each side (or mesh) can leverage these material properties individually. More than any other set of 3D functions in Photoshop, these material properties have a big effect on how your 3D content will look and interact with other parts of the scene, whether 2D or 3D. Material properties allow you to control everything from reflectiveness to opacity to the color of self-illumination. We discuss the different material options in more detail later in the chapter.
Figure 9.13 Filter by: Materials in the 3D panel offers the ability to edit the material properties of your 3D object, which in turn help define its visual surface characteristics.
Filter by: Lights. The 3D lights that illuminate your 3D object are controlled directly from the Filter by: Lights view. Each model starts with a default set of three “infinite lights,” which can be turned on or off. The Lights controls (Figure 9.14) let you create new lights—infinite, spot, or point—as well as control some aspects of each light individually. Point lights emit light in all directions, similar to a lightbulb. Infinite lights behave like sunlight, giving off light as if from a plane. Spot lights have a cone-shaped light beam, which can be made wider or narrower, and you can also adjust the hot spot and falloff of spot lights.
Figure 9.14 Filter by: Lights in the 3D panel defines the type, position, and properties of your 3D lights.
All the lights can be placed at the current camera position, and spot and infinite lights can be aimed at the origin from their current positions. To better see lights in your scene, you can use the “Toggle lights” icon at the bottom of the 3D panel, which turns on or off the light guides. Also at the bottom of the 3D panel, you can create or delete new lights and toggle the Ground Plane indicator to help with orientation. Understanding these options is key to defining the appearance of your model, so don’t overlook them.
The 3D Axis
One of the challenges of working in three dimensions is making precise movements when manipulating your 3D objects. To make this task more intuitive, the Photoshop team has included an object/camera control called the 3D Axis. To use it, choose one of the 3D tools; you should see the 3D Axis appear in the upper left of your workspace (the 3D Axis requires a GPU that supports OpenGL 2). By mousing over the different axes, you’ll see temporary rings and control blocks. Manipulating these controls allows you to rotate, scale, or move your object in one direction at a time. If you haven’t worked with 3D before, trust us: The 3D Axis is a big time-saver!
You can see the control surfaces on the 3D Axis in Figure 9.15. Keep in mind that the 3D Axis stays aligned with the object’s local orientation. That is, when you rotate the object, the 3D Axis represents that object’s original orientation regardless of how many times you’ve modified or saved the document. When you go back to your file in the future, the 3D Axis will still show you the object’s original orientation.
Figure 9.15 The 3D Axis allows you to position and orient your model or 3D shape layer.
The 3D Axis also lets you scale your object, either relative to one plane (or axis) only or relative to all axes at the same time. It does not allow you to scale in an arbitrary direction, meaning you cannot define a random axis along which to distort your object. You can approximate this by scaling along individual axes independently, but this does not always give you the same look. For example, you cannot stretch a cube along opposite corners, leaving all other corners in place. You will need to use a 3D modeling program for that task.