Tài iệu Photoshop cs5 by Dayley part 98 ppt

Part VIIWorking with 3D Images IN THIS PART Chapter 22 Creating and Manipulating 3D Objects Chapter 23 Using the 3D Panel to Edit 3D Scenes and Settings Chapter 24 Using Photoshop Tool

Part VII

Working with 3D

Images

IN THIS PART Chapter 22

Creating and Manipulating 3D Objects

Chapter 23

Using the 3D Panel to Edit 3D Scenes and Settings

Chapter 24

Using Photoshop Tools to Change the Appearance of

a 3D Layer

C H A P T E R

Creating and

Manipulating

3D Objects

IN THIS CHAPTER Understanding 3D file formats Creating 3D objects

Getting to know Repoussé Using 3D object tools Using 3D camera tools

The 3D environment in Photoshop has been a part of the extended

version since CS3, but it changed dramatically in CS4, and with the ability to turn vector paths into 3D meshes with Repoussé in CS5, the ability to open, maneuver, edit, and even create 3D objects has become

an important aspect of the extended version of Photoshop

Although you can create basic 3D models and add textures to them in

Photoshop, its main purpose is not to create, redesign, or even animate 3D

objects or scenes Instead, being able to work with a 3D object in Photoshop

allows you to use Photoshop’s powerful filters, styles, and other Paint tools

to dramatically improve the way a 3D image looks and to create fantastic

composites

A 3D object is usually composed of at least two different files: the 3D object

itself, which is a vector file, and the texture of the 3D object, or the file that

defines what the 3D object will look like, which is a raster file You need to

understand how these files work together in the 3D environment in order to

utilize the capabilities of Photoshop to change the look of a 3D object

The Layers panel also looks different with a 3D object selected A 3D object

with a texture attached has at least one sublayer, often more than one This

chapter gives you a complete overview of how to work with 3D layers

Understanding 3D File Formats

By adding the 3D extensions, Photoshop added a whole new array of

read-able file formats to its already impressive repertoire Photoshop supports five

3D file formats:

Part VII: Working with 3D Images

l 3DS: 3DS is a file format used by 3ds Max, the most widely used 3D application It has

become so much the industry standard that most 3D modeling programs of whatever type export their files in this format

l OBJ: The obj file format is also a widely used industry standard The 3D models that

come with the Photoshop bonus content are obj files

l DAE: Also known as COLLADA, this is the file format used by the video gaming industry

It was originally developed to facilitate transporting digital content from one creation tool

to another COLLADA is also a widely supported file format

l U3D: The Universal 3D file format allows users to share 3D graphics with other users who

don’t have the 3D modeling program used to design the image Like jpg or tif files, these files are working toward being universally available to most image viewers

l KMZ: This is the file format created and used by Google Earth This file format is specific

to the 3D geography that you see when you explore Google Earth

You can export 3D objects from Photoshop in all of the above formats except 3DS

Whenever you are working with a 3D model, you are working with a vector file Vector files are made up of geometric shapes that are defined by mathematical equations When you change the size of a vector file, the image is simply recomputed and the file doesn’t lose any quality

A 3D object rendered in wireframe mode is a basic example of how vector images work In the example in Figure 22.1, the outlines of the hat are stored in the computer numerically, with the length, width, and placement determined by mathematical equations describing each component

FIGURE 22.1

No matter how large this hat becomes, the lines that make up its wireframe stay crisp

Because 3D images are vector files, editing them is very different than editing a raster image You can’t directly affect a 3D object with the raster tools, such as the Paint Brush or filters These tools

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are designed to change pixels, and a vector file doesn’t contain any pixels, of course Photoshop can rasterize any vector file, making it possible to use any of the tools or filters on that file, but ras-terizing a 3D object flattens it, turning it into an image rather than a 3D model Sometimes when you are creating a composite, you want to do just that; but most of the time, you want your 3D objects to maintain their capabilities Fortunately, Photoshop has provided several ways of chang-ing a 3D object without affectchang-ing it directly

Opening and Placing 3D Files in Photoshop

As a general rule, if you work with 3D models often, you probably use a 3D modeling program that’s built to create 3D objects and is much better at it than Photoshop was ever meant to be

When you bring these models into Photoshop, your goal is probably to do one or both of two things: to change the texture of your 3D file or to create an image composite using a blend of 3D objects, photos, text, and other Photoshop elements

I’ve already shown you that a 3D model is a vector file, or a mesh, and it doesn’t contain any color information The texture of a 3D file is the raster file that is created to wrap the 3D object in, to give it color, texture, and definition If you are bringing a 3D object into Photoshop to add a tex-ture or edit the existing textex-ture, you probably want to open it just like you open any supported file

in Photoshop: Browse to the 3D file in Bridge or Mini Bridge, and double-click to open it in Photoshop

If you are creating a composite with more than one 3D object or other file, you want to place any secondary files into the first one as new layers You can do this using the File ➪ Place command, or you can place a 3D object by choosing 3D ➪ New Layer from 3D File

Using the File ➪ Place command places your 3D object inside a transformation bounding box that allows you to resize or rotate it before accepting the placement It also places it as a Smart Object,

as seen in Figure 22.2 In order to use any of the 3D tools on it, you need to double-click the Smart Object layer to bring up the embedded 3D file to work on

FIGURE 22.2

Using the File ➪ Place command places a 3D layer in a transformation bounding box and creates a Smart

Object layer

Part VII: Working with 3D Images

If you choose to create a new layer from a 3D file, the 3D object is placed into your file as a new layer at its default size and placement It remains a 3D layer, and all the 3D tools can be used to manipulate and edit it

Note

While working with 3D objects in Photoshop, change the workspace option to 3D, which docks the 3D panel

in the main pane The 3D panel allows you to create new objects, textures, and lights without using the 3D

menu n

Creating 3D Files in Photoshop

You can create basic 3D meshes in Photoshop in several ways You can use presets to create a quick and basic 3D object that doesn’t have a texture applied and doesn’t use an image as the tex-ture, you can use the grayscale brightness values in an image to create a depth map, or you can use multiple two-dimensional cross sections to create one 3D object These methods of creating a 3D object were all available in CS4 CS5 includes a new utility called Repoussé that allows you to cre-ate unique 3D objects from vector paths

You have two options for choosing how to create a 3D object: You can use the 3D menu or the 3D panel, both shown in Figure 22.3 The 3D panel is more versatile and easier to access, so in most cases, you want to use it to work from

FIGURE 22.3

You can use the 3D menu or the 3D panel to create new 3D objects

Note

If you have a 3D layer selected, these options in the 3D menu are grayed out and the panel options are

differ-ent Although you can merge 3D layers, you can’t create more than one 3D object on a layer in Photoshop n

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Selecting a source for a 3D object

When you use the 3D panel to create a new 3D object, you can use the drop-down menu to select

a source for that object You can choose from these sources:

l Selected Layer(s): Most of the time, you want to use the selected layer or layers to create

a 3D object This option uses only the content of the currently selected layer to create a 3D object

l Work Path: This option allows you to create a 3D object from a selected work path

Although you can create other 3D objects from layers containing paths (such as turning text into a 3D postcard, for instance), you can use the Repoussé function only if you choose this option

l Current Selection: This option uses the current selection to create a 3D object, cutting

the unselected areas from your image entirely Again, this option creates a 3D object using the Repoussé utility only

l File: This option uses the entire file to create a 3D object You want to use this option if

you have an image composite that you want to wrap around a 3D preset or manipulate into a 3D scene

Creating a 3D postcard

A 3D postcard is the simplest form of 3D object It is essentially a two-dimensional image or object that has been converted to a 3D mesh so it can be manipulated with the 3D tools It maintains its two-dimensional appearance, as you can see in Figure 22.4, but now you have the added versatility

of being able to quickly manipulate it in 3D space, adjusting perspective or creating a unique look

You also can use many of the 3D tools to modify it, including editing its texture, adding lights, or combining it with other 3D objects to create a scene

FIGURE 22.4

A 3D postcard is essentially a two-dimensional object that can be manipulated with the 3D tools

Part VII: Working with 3D Images

Creating a 3D shape from a preset

Photoshop ships with 12 presets that create basic 3D shapes that range from very basic shapes such as cubes to more complex shapes such as a wine bottle or hat These shapes use the selected layer as a texture If you have a white background layer selected, the object is white If you fill the background with a color or pattern, your object has that color or pattern If you open or import an image and select that layer when you create the object, the image is wrapped around the 3D object and becomes the texture, as shown in Figure 22.5

Note

You can easily edit textures in Photoshop, so if you’re not sure what you want to wrap your object up in just

yet, don’t let it stop you from creating it You can change the texture later n

FIGURE 22.5

Creating a 3D shape from an image layer wraps the image around the new 3D object

Just as with any presets in Photoshop, you can create and save your own objects as presets This isn’t done as easily as clicking a save preset button, however The 3D object must be exported as a DAE (Collada) file and placed in Program Files ➪ Adobe ➪ Adobe Photoshop CS5 ➪ Presets ➪ Meshes It then appears in the presets menu with the other shapes, ready to be created at any time,

as shown in Figure 22.6

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FIGURE 22.6

When you place a new DAE file in the meshes folder, it shows up in the presets list

Using Repoussé to create a 3D object

The Repoussé utility is new in Photoshop CS5 and gives you the capability to create a 3D object using a vector path Not only do you have the scope of creating almost anything with the vector tools to change into a 3D object, the Repoussé utility has many different options for how it is inter-preted into a 3D object

The vector layer can be anything—text, a shape, some clip art, or your own custom drawing The thing to remember is that Repoussé is not going to make a drawing of a complicated object look like a 3D model of that object An image of a car, for example, is not going to look like a die cast model after using the Repoussé utility Instead, it looks more like a mold of a car, with depth, but not much extra shape to the depth The end result depends on the settings you choose, of course,

so you might decide to make a 3D swirl from the shape of the car rather than a mold, but the important thing is that you still are very limited when it comes to creating very technical 3D objects

That being said, the Repoussé utility serves an amazing function when it comes to bringing your Photoshop creations to life and giving them new depth

Follow these steps to see how you can create a new 3D object using Repoussé:

1 Create a new blank document of any size.

2 Create a vector path in the new document

I suggest you do something simple to start I typed my name.