Tài iệu Photoshop cs5 by Dayley part 100 pptx

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Note
Your image doesn’t have to be in grayscale for this to work. Photoshop uses the green channel to create a
depth map.
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This type of 3D object is great for creating textures or another unique look for an image file. They
also can be used to create planes from elevation maps or to save and recreate planes from one 3D
modeling file to another. A simple image file can quickly become a mountain range, as seen in
Figure 22.15.
FIGURE 22.15
Using an image to create a depth map can quickly create interesting planes.
Creating a 3D volume
The 3D volume option is used to create 3D objects out of image files that are slices of 3D objects,
such as several DICOM files that are created by taking slices out of the center of an image. Using
this option allows you to create a 3D object from the image layers that can be moved, manipulated,
and viewed from all angles, giving you a versatile way to view these medical images.
Creating 3D Objects in the Layers Panel
The layers of a 3D object are more complicated than most images. When you open a 3D object in
Photoshop, unless that object doesn’t contain any textures at all, you have at least one sublayer
listed under a textures heading. On top of that, every filter you can add or edit you can make to a
3D object that involves the Layers panel in one way or another. It doesn’t take very many changes
to add several layers to a 3D file or composite. Don’t panic yet: Like a well-organized filing cabinet,
the Layers panel is a clean and efficient way to organize your effects and filters.
Figure 22.16 shows the Layers panel after creating a ring by using the 3D shape from the layer
option. The thumbnail of a 3D layer is distinctive. It includes the icon of a three-dimensional cube
in the corner in addition to the thumbnail of the actual 3D object. This indicates that the 3D menu
is active and the 3D tools can be used on this layer.
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FIGURE 22.16
A 3D layer in the Layers panel
Notice the sublayers. The primary sublayer is named Textures, and underneath it is another layer
labeled Background. This layer is the texture that has been applied to the 3D mesh to give it surface
area and color. It is named Background because I didn’t bother to change the name of the back-
ground layer before I created a 3D object from it. This layer is actually an embedded file. Double-
clicking this layer opens the background layer as a separate two-dimensional file that I can change
and rename if I want. I also can add more textures to this object, which show up as additional lay-
ers under the texture sublayer. Each of these textures can be opened and edited individually.
Cross-Ref
Editing textures is a primary reason to bring a 3D object into Photoshop. I cover this aspect of 3D objects in
greater detail in Chapter 24.
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Manipulating 3D Objects
Imagine that you are standing in a room. As you move in a straight line left to right, you are mov-
ing along the X-axis. If you were to jump up and down in place, you would be traveling along the
Y-axis. This is a two-dimensional plane, in which coordinates can be given with two numbers: an
X location and a Y location. When you work with a two-dimensional file in Photoshop, you are
working with an XY plane. To add the third dimension, the Z-axis is added, creating depth to the
XY plane. To move along the Z-axis you would walk front to back within the room.
The 3D tools in Photoshop allow you to move 3D models within all three of these planes. If you
are already familiar with any 3D modeling software, you will find the tools used in Photoshop
familiar. Photoshop has designed its manipulation tools to a very standard look and feel. If you
have never used 3D tools, you will find that they are fun and easy to use. Jumping in and working
with them as we introduce them to you in this chapter is the best way to familiarize yourself with
them very quickly.
As you work with your 3D model, keep in mind that your final product in Photoshop will be a
two-dimensional view, not a 3D scene or animation. This helps you keep in perspective what you
can accomplish in Photoshop and how to do it.
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Understanding static coordinates
If you are familiar with 3D modeling software, you should be aware of one important difference in
Photoshop. The 3D tools in Photoshop change the selected 3D layer, not the 3D scene. When you
roll, rotate, or otherwise change the position of a 3D object, you are simply changing your view of
it, not its positioning relative to the scene it was created in. Being able to manipulate your 3D
object allows you to make changes to its texture and place it in a composite that eventually
becomes a two-dimensional image.
That means that the X, Y, and Z planes remain static. Whether you are manipulating a 3D layer or
the camera, X and Y are always side to side and up and down, and Z is always depth. Just imagine
that you are looking at the 3D objects through a window that doesn’t move. You can move the 3D
objects around behind the window, but you can’t go into the room and walk around among them
like you can in a standard 3D modeling program.
Using the 3D object tools
The 3D object and camera tools are located in the Toolbox, as shown in Figure 22.17. When you
select the active tool by clicking it or hitting K on the keyboard, the Options bar changes to show
not only the options that are available for the tool, but all the other 3D object tools, as shown in
Figure 22.18. These tools are used to move your object through 3D space.
FIGURE 22.17
The 3D tools
Object Rotate tool
Camera Rotate tool
FIGURE 22.18
The options bar for the 3D object tool
Tool
presets
Rotate Drag Scale Save current view
Delete currently selected view
Home (return to initial object position)

Roll Slide
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The Home button
The first button in the options bar is the Home button. At any time while you are manipulating
your object, you lose it in “outer-space,” or just feel as if you’ve contorted its position beyond
repair, you can hit the Home button to bring your object back to its initial position.
Tip
It is incredibly difficult to explain moving an object through 3D space in a book with still shots. The quickest
way for you to understand what I am trying to teach you is for you to use the tools in conjunction with this
book. Create a quick 3D object by opening a new document, choosing 3D ➪ New Shape from Layer, and
choosing a shape from the menu. An irregular shape, such as the hat, is the best for seeing the difference that
moving it makes.
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Turning 3D objects around a central point
Turning a 3D object around a central point is done by using tools to rotate or roll that object.
Rotating or rolling an object turns and skews it around the X-axis, Y-axis, or Z-axis. While using
the Rotate and Roll tools, your object moves around a center point, which never changes position.
Changing an object’s orientation is the most obvious reason to use the Rotate and Roll tools. But
you also can change the lighting on your object. As you move your object, notice that if you have a
light placed in your scene, the lighting changes on your object.
Another use for the Rotate and Roll tools is checking the texture of your object and making sure it
is the way you want it, especially if you made any changes to it in Photoshop. You can select the
Home button at any time to return your scene to its original settings.
You can turn a 3D object around a central point using the Rotate and Roll tools, or you can enter
the orientation numerically in the options bar.
Rotating a 3D object
Using the Rotate tool rotates the 3D object around the X-axis and Y-axis. The X-axis is a line run-
ning side to side through the center of an object. Like a hot dog turning on a roasting stick, if you

rotate your object only on the X-axis, the top of the object rotates toward you or away from you.
The Y-axis runs up and down through the center of your object. As you rotate your object around
the Y-axis, the sides of the object move toward you or away from you.
Click and drag back and forth across your 3D object to rotate it along the Y-axis or drag up and
down to rotate it along the X-axis, as shown in Figure 22.19. You can constrain the rotation to
either the Y-axis or the X-axis by holding down the Shift key as you drag in the appropriate
direction.
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Note
As you manipulate your 3D object using the 3D tools, you notice that the 3D Axis Widget (shown in Figure
22.19) also moves in relation to the position of the 3D object. I show you how to use the widget to manipulate
a 3D object later in this chapter.
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FIGURE 22.19
Rotating an object around both the X-axis and Y-axis
Rolling a 3D object
Rolling your object around the Z-axis is a similar concept to rotating your object around the X-axis
or Y-axis. Visualize a line running from front to back through the center of your object, allowing it
to roll left to right and back again. You can roll your object around the Z-axis by clicking and drag-
ging back and forth with the Roll tool, as seen in Figure 22.20.
Tip
Although you can quickly skip through the 3D object tools by repeatedly pressing K, you also can use the
Alt/Option key to temporarily change the Rotation tool to the Roll tool, and vice versa.
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FIGURE 22.20

Rolling an object around the Z-axis
Moving a 3D object through 3D space
Dragging or sliding a 3D object moves it to a different location in your 3D workspace. Moving
your object allows you to place it in the desired position so you can create composites by adding a
photo background or other 3D objects. You also may want to move an object to adjust the lighting
or change the perspective.
Dragging a 3D object
Dragging moves the object around the XY plane and is visually similar to using the Move tool to
move a selection in a regular image file. You can drag your object by selecting the Drag tool in the
options bar or the Toolbox, as seen in Figure 22.21.
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FIGURE 22.21
Using the Drag tool
Tip
You can toggle between the Drag and Slide tools by holding down the Alt/Option key.
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Sliding a 3D object
Sliding moves the object along the XZ plane, so you can move it side to side, just as you can with
the Drag tool, or in and out along the Z plane. As you move your object toward you or away from
you along the Z plane, it looks very similar to scaling, or resizing, your object, as shown in Figure
22.22. Although it looks the same, when working with 3D, sliding an object is a very different
effect from actually making the object bigger or smaller, just as walking away from an object in real
life doesn’t change its actual size, just your perspective of it.
When you have the Drag or Slide tool selected, you can change the position of your 3D object
numerically by entering values in the X, Y, or Z indicators in the options bar.
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FIGURE 22.22
Using the slide tool
Scaling a 3D object
Scaling a 3D object in Photoshop is very similar to using the Transform tools to scale an image or
selection. By selecting the Scale tool, you can click and drag across your object to make it bigger or
smaller, as seen in Figure 22.23. As you change the size of your 3D object by using the Scale tool,
the proportions of the object are automatically maintained. By holding down the Alt/Option key
while you click and drag, you can adjust the object non-proportionally by making it taller or
shorter. If you hold down the Shift key, you can make your object wider or narrower.
When you have the Scale tool selected, you can change the size numerically by entering values in
the X, Y, or Z indicators in the options bar. This is usually a better way to scale your object dispro-
portionately. You also can change these values by scrubbing across the letter that applies to the
value you want to change.
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FIGURE 22.23
Use the Scale tool to make 3D objects larger or smaller.
Changing positions and saving a view
As you manipulate a 3D object, you can change the position of it to several presets, as shown in
Figure 22.24. When you change the position of your object using the menu, you lose any position
changes you have already made to it.
If you’ve created a position that is different than any of the presets, you can save the position by
clicking the Save button and naming the new position. It is then added to the list of presets, and
you can access it at any time. You can delete the view by selecting it in the drop-down menu and
clicking the garbage can.
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