INSIDE 3DS MAX® 7 [Electronic resources] نسخه متنی

Tools: Workflow Timesavers

Time is the one thing we can never make more of, but we sure can waste what we already have. Any time a 3D program saves us time and speeds our work, it's cause for gratitude, because all too often, 3D workflows (the processes of getting a job done or achieving a particular effect) force you to take many more steps than you really should need.

Luckily, 3ds max 7 has added some small but significant improvements in workflow that will give you back a measure of your precious time. These include:

Paint Selection Region
Object Display Culling
Array Preview
Quick Align
Clone and Align Tool
Snaps Improvements

Paint Selection Region

Paint Selection Region is a new method for selection similar to the Lasso Selection Region method. Instead of clicking in or creating a marquee window around objects to make a selection, the mouse is dragged (maybe stroked is a better word) over the objects, as if painting with a brush. This is a good tool to use when you want to select an irregular but well-defined area.

As with the other selection methods, the Alt key is used to subtract from the selection and the Control key to add to it. The default size for the Paint Selection Region brush is 20; that can be changed from the General tab within the Preferences Settings dialog. There is a way to interactively increase or decrease the size of the brush tool, but we need to customize a keyboard shortcut for Paint Selection Size Down and Paint Selection Size Up actions from the Customize User Interface dialog.

Working with Paint Selection Region

We'll start by making our own keyboard shortcuts to make the Paint Selection Region brush larger and smaller, and then do some experimenting with how to use this new feature.

From the Customize menu, choose Customize User Interface.

Within the Action list, scroll down to highlight Paint Selection Size Down.

Place the cursor in the Hotkey box, press both the Shift and the minus key on the keyboard, and click the Assign button. In the Action list, to the right of Paint Selection Region, the combination Shift (Shift together with the minus sign) is listed as the keyboard shortcut (Figure 1.9).

Figure 1.9. After pressing the Assign button, the Hotkey Shift (Shift in combination with the minus sign) is assigned to Paint Selection Size Down.

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Repeat the previous steps to assign Shift= (Shift together with the equal sign) to the Paint Selection Size Up action.

To better understand Paint Selection Region, let's try the following:

Open the scene entitled Paint Selection Region start.max. Switch from the Top viewport to the Perspective viewport to see vertices that form a letter S raised from a Plane primitive. We want to create another selection of vertices that form a skinnier S shape, and then lower that selection.

In the Top viewport, select the Plane object. Zoom in close enough to see the Plane completely fill up the view. If it does not, press the Z key to zoom to the extent of the selected object.

Activate Vertex mode and press the Q key until the Paint Selection Region button is active in the Main toolbar. Then Paint the selection of vertices in the middle of the S shape (Figure 1.10).

Figure 1.10. An S-shape vertex selection is painted with the selection tool and Paint Selection Region.

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Change to the Perspective viewport and activate the Select and Move tool. Within the Transform Type-In field at the bottom of the user interface, enter for Z the value 0.0 (Figure 1.11).

Figure 1.11. From the Perspective viewport, the selected vertices have been moved down to Z = 0.0.

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Open the file entitled Paint Selection Region finish.max to see the finished example.

Of course, the same vertices could have been selected by using either the Fence or Lasso Selection Region, but these tools would have required numerous clicks of the mouse. By painting the selection, only a single curvy stroke is needed.

Object Display Culling

Want more speed in your screen redraw (and who doesn't)? Object Display Culling allows you to quickly hide and unhide objects to maximize the available display memoryand therefore screen performance. Basically, Object Display Culling makes decisions on whether or not to display objects onscreen in full resolution or as bounding boxes according to rules such as how far the objects are from the camera, how many polygons they have, and what the viewport framerate is. When screen memory and graphic card performance are limiting factors, as they often are for big scenes with many complex objects, you can really save time, or in some cases work with a scene that you otherwise could not (Figure 1.12).

Figure 1.12. Access Object Display Culling from the Utilities Panel: Alt-O toggles Object Display Culling on and off.

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Culling Boxes

To better understand how Object Display Culling works, complete the following steps. You'll find that the next exercises are sensitive to the current speed of your computer; you may have to use higher settings on a faster machine to see culling in action, while lower settings on a slower one will help prevent a stall.

Open the file entitled Object Display culling start.max. The scene opens in the Perspective viewport with an array of 100 Instances of a box made of editable polys (not a Box primitive).

Pan and zoom the scene. With a reasonably fast computer, 100 boxes at six polygons per box should not cause any significant problems for your viewport performance. Difficulties start when each object is more complex.

From the Utilities panel, click the More button and choose Object Display and Culling.

Check the Enable box, uncheck Self-Adjust Framerate, and set the Target Framerate to 30.

By disabling Self-Adjust Framerate, we guarantee that the viewport performance will remain at 30 frames per second. This Target Framerate is high and will cause many of the objects to be culled and displayed as bounding box instead.

Objects will also be culled according to their number of polygons. Select one of the boxes, activate the Modify panel, drop down the Modifier list, choose the new TurboSmooth modifier, and set the Iterations at 4.

The new TurboSmooth modifier is closely related to the MeshSmooth modifier, but is optimized for viewport performance. Assigning four Iterations to TurboSmooth will cause all 100 boxes, each with six sides, to be subdivided four times, resulting in hundreds of thousands of polygons added to your scenea big advance in complexity over the 600 polygons in the scene we had before. If your computer is really fast, you may still not notice much difference in performance, so go ahead and try adding more Iterations and run the TurboSmooth modifier again. (Go too far, however, and you risk a stall or crash.)

Now try panning, zooming, and arc-rotating the viewport. Notice that many of the more distant boxes will disappear as the viewport changes (Figure 1.13).

Figure 1.13. The front box is selected. The boxes further away in the back have been culled. The Target Framerate is set to 30.

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Now set the Target Framerate to 15, and try panning as we did before. Notice that more of the boxes will display, but the viewport performance is slower (Figure 1.14).

Figure 1.14. Some of the boxes in the back have returned with the Framerate set lower to 15.

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The finished project, Object Display Culling finish.max, can be loaded from the DVD.

Array Preview

Use the Array Preview, new to 3ds max 7, when you want to copy objects and space them out precisely. In prior versions, this task required you to go back and forth to the Array dialog to input new values and see the results, which were visible only after accepting changes. Now you can see what the results will be interactively, and make changes much more quickly. It's another great 3ds max 7 timesaver.

Array Preview also has an option to preview the scene as bounding boxes instead of fully rendered geometry. Use this for larger scenes where creating an array of many objects would slow down the viewport interaction.

Note

The Array dialog cannot be resized and will not allow you to pan or zoom the scene while it is open. It can be difficult to see the preview of new objects if the viewport Is already panned or zoomed in the wrong position, so prior to opening the Array dialog, make sure the scene is fully visible.

Create a Spiral Staircase

Let's test the new Array Preview's powers by creating a spiral staircase.

Open the file entitled array start.max on the DVD. Note that the viewport is panned and zoomed, with a single Stair object sitting at the bottom left corner of the view. This will leave room for the Array dialog to be present with enough screen room available for previewing the copies. Select the Stair object and note that its pivot point is away from the object and is in the origin of the World coordinate space (Figure 1.15).

Figure 1.15. The scene is panned so that we have enough room to preview the arrayed objects as well as the Array dialog. The pivot point is away from the object.

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Select the Stair object and open the Array tool from the Tools menu. The Array dialog pops up. Choose Instance from this dialog so that changes made to the selected Stair object will apply to ones we create in the following steps.

Place the Array dialog box as far to the bottom right-hand corner of the 3ds max 7 window as possible, so that we can see the preview later.

Set Z Move to 15, Z Rotate to 10, and Count to 20, and press the Preview button. In this example, we can leave the option for Display as Box unchecked, since this scene is low in Polygon count. We should see the stairs arcing one by one as they climb (Figure 1.16). Note that the Array tool copies objects based on the location of their pivot points, so the stairs are copied in an arc as wide as the distance between the pivot point and the stair.

Figure 1.16. Previewing the spiral stairs.

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New Align Tools

Normally, in 3ds max, you would use the Align tool to accurately place an object to the position and orientation of another object. Within the Align Selection dialog, you can choose which part of the selected object will become aligned with which part of the target object. Other controls determine which axis gets aligned, as well as deriving the orientation and scale of the target object.

Quick Align Tool

These features are essential when you need absolute control over many aspects of alignment. However, often all you need is to move one single object to the pivot point of another single object. For this simple task, it's quicker and easier to use the new Quick Align tool (Figure 1.17). Find the new Quick Align feature by dragging down on the Align tool from the Tools menu and the Main toolbar, or by pressing Shift-A.

Figure 1.17. Quick Align is a subfeature of 3ds max 7's standard Align tool. With the Post object selected, Quick Align will move to a target object.

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Quick Align operates instantly. You do not need to make choices inside a dialog. With the Quick Align tool, an object or selection of objects will move to a single target object.

Clone and Align Tool

Often, you need to copy an object or selection of objects to the location of several objects. For this, use the new Clone and Align tool. Clone and Align is similar to the Quick Align tool, except that it gives us the choice of picking which objects in the scene will be the destinations of the selected object or objects. The Clone and Align dialog also gives us the choice of offsetting, orienting, and scaling the copied object(s) based on any XYZ coordinates you specify.

To demonstrate the Clone and Align tool, let's create copies of a post for each stair.

Open the file entitled clone and align start.max. The project opens in the User viewport. The objects are the same as the stairs in the last example, but we have added a Post object we want to copy.

With the post selected, choose Clone and Align from the Tools menu (Figure 1.18).

Figure 1.18. Select the Post object before choosing Clone and Align from the Tools menu.

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The Clone and Align dialog pops up (Figure 1.19). Fortunately, this dialog does allow us to pan and zoom our scene so that we can see what is going on within the preview.

Figure 1.19. A Post object will be copied and placed on each Stair object that is picked from the list in Pick Destination Objects.

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Click the Pick List button, and select all of the Stair objects. Note that the new posts overlap and are stacked on the stairs' pivot points.

Arc-Rotate the User viewport so we can clearly see each post. Set Align Offset (Local) X to 185 and Y to 10; click the Apply button and close the dialog box. A Post object will be copied and placed on each Stair object (Figure 1.20).

Figure 1.20. Rendered version of the stairs with lights and a ground plane added.

You can see the finished project in the clone and align finish.max file on the DVD.

Snaps Improvements

Sometimes accuracy is much more important than flexibility, even when you're artistically modeling and designing a scene. You often really need exact precision, and in those cases the Snaps tools have always been your friend. However, when you are in a hurry, you may not have the time to get things just so, even with the help of Snaps. That's where 3ds max 7's new Snaps improvements come in.

Now, for example, when creating a line, snapping to grid points ensures that the vertices are plotted exactly on the intersections of the home grid. In past versions of 3ds max, you would have had to set the Grid to an appropriate spacing first.

Snaps previewing is another big assist for accurate object placement. In the past, if you placed the cursor next to a grid point and clicked the mouse, the object would snap, but not always where you expected, and you'd have to go back and move it again. 3ds max 7 now includes the ability to preview where the snaps will place the object before you actually move it there. If your cursor is within 30 pixels of the grid, a preview will let you know where the cursor will snap. If your cursor is within 20 pixels of the grid, the snap will take place. Seeing the snap before it takes place allows you to make proper adjustments with the mouse to ensure that the snap occurs where you want it.

Snap Radius is the distance where the object will snap, and the Snap Preview Radius is the distance where the Snap function will anticipate the snap without actually committing the object's position. For the Snap Preview Radius to work properly, make sure that the Snap Preview Radius is set higher than the Snap Radius. If the Snap Preview Radius and the Snap Radius are too close in value, you will not see any preview.

Playing with Snaps

Here is an example of how to use the new Snaps features. We will move a rectangle so that its corner is positioned to a specific grid point.

In the Perspective viewport, create a rectangle. Set the length at 50 and the width at 50.

Right-click any gray area of the toolbar and choose Snaps (Figure 1.21). Right-clicking beneath the word View in the Toolbar also opens the Snaps toolbar. Both the Snap to Grid Points toggle and the Snap to Endpoint toggle are active. The Snaps toolbar can be docked to the top for convenience.

Figure 1.21. Create a rectangle in the Perspective viewport.

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In the Main toolbar, right-click the Snaps Toggle button. The Grid and Snap Settings dialog will pop up. Make sure that only Snap to Grid Points and Snap to Endpoint have a check mark.

Press the S key to toggle the Snaps on. Use the Select and Move tool to drag the rectangle by its upper left corner to the coordinates (0,0,0). A new feature of 3ds max 7 is a blue rubber-band line that will show where the rectangle was and where it is going as it is moved to the middle of the coordinate system (Figure 1.22).

Figure 1.22. A blue rubber-band line indicates the positional change of the object while it is being snapped. Note that the Snaps toolbar is docked to the top.

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The Transform settings indicate that the pivot point of the rectangle is now located at (-25,-25,0). This is because the upper left corner is now located at (0,0,0), and the object has a length of 50 and a width of 50.