Difference between revisions of "XSI Beginner Tutorial"

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This tutorial will give you a quick introduction to using Softimage|XSI and/or the [[XSI Mod Tool]] (which we'll refer to from now on simply as XSI). Basic operations, like navigating viewports, creating polygon primitives, transforming primitives, selecting objects and components, and basic mesh editing procedures will all be covered in this article. For more information, please refer to the [http://softimage.wiki.avid.com/xsidocs/hh_start.htm official XSI documentation].
 
This tutorial will give you a quick introduction to using Softimage|XSI and/or the [[XSI Mod Tool]] (which we'll refer to from now on simply as XSI). Basic operations, like navigating viewports, creating polygon primitives, transforming primitives, selecting objects and components, and basic mesh editing procedures will all be covered in this article. For more information, please refer to the [http://softimage.wiki.avid.com/xsidocs/hh_start.htm official XSI documentation].
  

Revision as of 22:04, 12 May 2008

This tutorial will give you a quick introduction to using Softimage|XSI and/or the XSI Mod Tool (which we'll refer to from now on simply as XSI). Basic operations, like navigating viewports, creating polygon primitives, transforming primitives, selecting objects and components, and basic mesh editing procedures will all be covered in this article. For more information, please refer to the official XSI documentation.

Disclaimer

Note:If you are an XSI beginner, but have experience using other 3d packages like 3DStudio Max, Maya, or Lightwave, the following guides will help your migration.

Moving Around: Navigating Viewports

Overview of XSI
Camera Tools

Learning how to move around in XSI's 3D viewports is BY FAR the most important skill to master, because when you start doing more complex things, like texturing and splicing, you will need to have precise control over your view. Otherwise, much heartache and ingestion of caffeine will result.

So, to get started, open up your copy of XSI. Depending on which version you have, the default viewport layout will consist of either one or four panels. The image on the right shows a scene of a water fountain depicted in four separate viewports. These viewports are (going counterclockwise) Top, Front, Right, and Camera.

Note:If your version of XSI displays only a single viewport on startup, don't worry. It just means that one of your viewports has been maximized and is covering the other viewports. You can show all four panels by clicking on the resize button in the upper right corner of the viewport. This button works the same way as it does for a regular window. You can maximize or restore any viewport at any time by clicking on this button.
Resize icon
The resize icon

The Camera Icon Menu

Camera icon
The camera icon

If you click the little camera icon (with the triangle underneath) above the 3D view, you will produce a drop-down menu that contains a lot of choices (shown in the image to the right). XSI gives you a lot of different ways to view your 3D scenes, but we will only be covering the most useful ones for XSI beginners in this tutorial. If you look at the bottom half of the drop-down menu, you will find a list of navigation tools.

A few of the most useful tools to know about are the Navigation Tool (S), Pan & Zoom Tool (Z), Orbit Tool (O), Dolly Tool (P), and Roll Tool (L).

Note:All tools show their mouse button assignments on the status bar at the bottom right of the screen with left, middle, and right options respectively. To see what a particular mouse button does when you are using a particular tool, just check down there.

The Navigation tool

Using the Navigation tool (S), holding down the left mouse button produces an effect similar to Black and White, where you can drag your canvas around in a two dimensional sense. The right mouse button allows you to rotate your model about the axis in the middle of your view in all directions (X Y Z). The middle mouse button zooms in and out when held down and the mouse is moved up and down. The Navigation tool is an all-purpose tool that allows you to perform the most common types of navigation quickly and efficiently, but it is not the best tool for all occasions.

The Pan & Zoom tool

When using the left mouse button, the Pan & Zoom tool (Z) does the same thing that the Navigation tool does, allowing you to drag your canvas around freely. The middle (zoom in) and right (zoom out) mouse buttons are a bit deceiving: you may think that they are moving the camera closer to the scene, as would happen if you walked closer to an object you were photographing, but they don't! These tools actually operate like the zoom lens on a camera, and zoom in and out by changing the viewing angle. This can affect the appearance of objects, making it look like you're looking through a fishbowl or wide angle lens. If you manipulate objects in this view, everything you do will turn out looking different after exporting it, so be careful: it can really mess you up! This tool can be very useful in 2D views because it allows for a precise zooming, but be careful about its use in a 3D view.

Orbit, Dolly, and Roll

These tools, Orbit (O), Dolly (P), and Roll (L) are very useful when you get to rendering because it will allow you to position your camera like a true movie director. In order to achieve life-like animation of your camera, you need to use orbit, dolly, and roll, otherwise scenes tend to look artificial at best. (Then again, that may be the look you are going for. :) )

The Walk, Fly and Drive tools (WASD control)

If you want to control the camera using the W, A, S, & D keys, then click the small camera icon and choose Walk Tool, Fly Tool or Drive Tool. In order to move around using any of these tools, you must first press and hold one of the mouse buttons. With the Walk or Fly tool, the speed of the movement changes depending on the mouse button that you select. Using these tools, you can change the direction that you are facing (pivot) by moving the mouse. The Walk tool allows you to move around your scene in a way that will be very familiar to FPS fans: you use the WASD keys to move, and the mouse to turn your head and change your direction, so it is a lot like walking around your scene. The Fly tool will feel familiar to mappers, because it is similar to the way that you move around your scenes in Hammer, allowing you to move both vertically and horizontally.
There is also a Drive tool, but it is a little different from the other tools and takes some getting used to. When using the Drive tool, the mouse button that you hold doesn't change the speed, but the type of action you can perform, allowing you to slide, turn, or pivot. When you press the left or middle mouse button, four orange brackets will appear in the center of the screen, dividing it into quadrants. You move around by moving the mouse over these quadrants and use the WASD buttons to pivot or slide. The white arrows that appear on the viewport show you the direction that you are currently moving.

Making Things: Creating Polygon Primitives

Now you know how to move around your viewport, but there's not very much to see! The first thing that you're going to want to do is create some objects to work with. The easiest way to create an object in XSI is to use one of its premade primitives.

Creating a cube primitive

Creating a simple cube
Creating a cube in mod mode

The steps you use to create a cube differ slightly depending on the mode you are using. To create a cube in XSI pro mode, first make sure that your menu set is in Model mode (the first button on the toolbar on the left). Then select Get: Primitive -> Polygon Mesh -> Cube as depicted in the image to the left. A small window displaying the cube's creation parameters will pop up and a cube should appear in the viewports.

To create a cube in XSI Mod Tool mode, select Create: Objects. A small floating window will appear depicting icons for several different types of primitives. For the purpose of this tutorial, select the cube icon. This will create the creation parameter dialog box and a cube will appear in the viewports. The creation parameters dialog box is the same in both modes and appears in the Mod Tool mode image on the right.

The default settings create a cube that is 4 or 8 units in length in each dimension (depending on your mode). You can change the size of the cube at the time of creation by editing the creation parameters window. To change the length of a side, you can either change the number in the Length box, or move the slider beside the number field. To change the number in the text input field, select it with the LMB and type in the new number. Press return, or click on another field to apply the change. To move the slider, either press the LMB anywhere in the slider, or press and hold the LMB and drag the slider wherever you like. You'll notice that the slider allows for a lot of precision, and that you might want to edit the number field to get rid of any fractional elements if you like to work with round numbers.

Go ahead and change the number to anything you like. Remember that one unit in XSI is equal to one unit in HL2 which is roughly equal to an inch (2.5 cm). You are now the proud owner of your very own cube!

Selecting and Moving Things: Selecting Objects and Transforming Primitives

When you create a new object, it is selected by default.

Some notes on selections

You can't save your select mode preference in XSI Mod Tool. Every time XSI Mod Tool is started it resets “Select Single Object in Region? and “Extended Component Selection? to enabled. The latter will keep things selected until you manually de-select them using middle mouse button click or Ctrl+Shift+A which also disables right click context menus.

I recommend you to uncheck "Extended Component Selection" every time you run the application unless you were familiar with Softimage|3D.

Note:In the latest download this can be found in File > Preferences. It comes under the "Select" category and is named "extcomponetsel"

Selecting Parts of Things: Component Selection

Everyone likes cubes, but cubes are damn boring, especially if all you have is a cube! So here we will take our cube and make a sweet looking object out of it, or at least try to!

Manipulate vertices

Selecting the Vertex
Moving the Vertex
One thing that I have noticed: when you scale or rotate an object in XSI, then go to export it into the SMD file, compile it, and use it in your game...the model's shape looks incorrect. To avoid this, make sure and use the freeze all transforms command under the transform section of the Main command Panel (MCP). This resets the surface normals to their correct values. Now that we have a cube, you can use what we learned above to get it looking good in our views, so that we can actually see what we are doing.
In order to enter vertex manipulation mode, press T or click Point underneath the Select bar on the right hand side. I call them vertices, XSI calls them points, same difference. Moving on, you can click a vertex in the 3D view or any 2D view, and it will turn red if you did it right. A word of caution: in the 2D view, if you click a vertex/edge/polygon, it WILL select all vertices directly behind it as well out to infinity, so I suggest doing it in 3D view unless that is your intention!

For your reference, you use your left mouse button to select vertices, and your right (or middle) mouse button to de-select vertices if extended component selection is turned on. If it is turned off pressing CTRL will de-select already selected objects and SHIFT will continue selection of objects.

Another good tool for editing components (like points, edges, and polygons) is the tweak component tool, "M" this lets you move freely between editing points, edges, and polygons. (XSI v5.0 ONLY) with the tweak component tool, you may also use to target welds on components.
Okay so now that you have your vertex selected, there are about a lot of ways to move it! You can do it in 3D view, 2D view, translations, etc. My suggestion is doing it in the 2D view with grid snap on (press CTRL or click the boxes to match the ones on the right). You can edit how much snap you have by scrolling your mouse wheel in a 2D view (you'll see a hatched box moving). You can then press the T circular button on the right and enter translation mode (or press V). You can limit which axis you want to translate over by clicking the X, Y, or Z buttons (highlighted means it can move in that direction). Now experiment with moving your vertex around, but when you're done, come back please!

Manipulating edges

Manipulating Edges
This is exactly like doing vertices, except you are now moving edges. Edges are the bars you see connecting the vertices together; they create the shape and are the template the 3D engine uses in order to make the polygons that everyone talks about. Anyway, so now that you have the edge selected, you can move it around just like you do with the vertices; I won't waste time repeating how.

Manipulating polygons

Manipulating Polygons
The funny thing about polygons, as you may soon find out, is that they are VERY HARD to select, but by pressing U, you will enter "ray-cast polygon selecting mode", which will allow you to select polygons in the 3D view by just clicking on them. This also works in the 2D view. This, along with many other ways to select stuff, is found in the SELECT menu on the right under tools and modes. Once again, the manipulation of polygons is exactly the same as written above.

More selection options

  • F7: Rectangle selection
  • F8: Lasso selection
  • F9: Freeform selection
  • F10: Raycast selection
  • Shift+F10: Rectangle-Raycast
  • F11: Paint selection
  • Alt-LMB two components: Range selection
  • If Extended Component Selection is on
    • Ctrl-MMB: Loop selection
  • If Extended Component Selection is off
    • Alt-MMB: Loop selection

Changing Things: Basic Mesh Editing

Splitting Edges
Oh boy, this is by far my favorite part of XSI compared to any other 3D modeling program I have used thus far. In XSI there are about 15 billion different ways to make a very complex cube. I will give details on three of them in this section of the tutorial. All three of these are very complex beasts, and I am sure there are better ways to do the things I will show you, but with today's computing power, what are 15 extra polygons going to do to you?

Splitting

The first step to splitting something is to select it. The most common thing to split is an edge, because it's pretty straightforward what you are splitting. So select an edge as described above and follow along closely. Under Modify, click Poly Mesh then click Split Edges (With Split Control). Click the checkbox that says Parallel Edge Loop, which creates an edge around the entire object you are currently working on, sort of like slicing it with a knife while keeping both sides together. You can now play with the slide bar to precisely position the split to the desired location on your cube (it's a percentage sort of thing). When you're done, close the properties box; there is no more need to play with the split. Uncheck the parallel edge check box if you only want to split the selected edge, rather than all around the cube.

Beveling

Beveling
You thought splicing was way cool? Wait until you see the sweet effects you can create with the bevel tool. If you refer back to the first picture, you can see a somewhat rounded edge on the base of the spout of the water fountain. This is achieved by using beveling. Believe it or not, that was made from a cube. Anyway, beveling is used to taper edges, corners, or whatever. It's like the arch tool in Hammer, only this is taking an existing edge, splitting it twice, then making it adjustable! First, select each edge that you want the bevel to be applied to. After that, under the Modify section, click Poly Mesh, then click Bevel. You will see that instantly your selections will be doubled, and in the property box you can change the amount of bevel applied to your edges. Go ahead and play around with that. To achieve good smoothing results, click the edge in the middle of the previously beveled components and bevel again. This will amaze your friends who think you are sitting there laying down vertices left and right! Either that or they'll beat you up for being an uber dork...

Subdividing

Subdividing
Subdivisions can be thought of like displacements in Hammer. To subdivide, you need to select a polygon (remember that ray-cast thingy U) or edge, then under the Modify section click Poly Mesh then click Subdivide. This will bring up a properties box and turn your polygon into a mess of diamonds, or something like that. You have several options of subdividing at your disposal, including: Plus Signs, Diamonds, X's, and the ever useless Triangle. I have no clue what you use triangle for, only to piss you off when you realize you can only make one of them!? Well, when you finally choose your pattern and the number of iterations (e.g. the density of the new 'mesh'?), you can begin playing with your new creation by translating those points, edges, and polygons around to make a beautiful masterpiece! If you select an edge and subdivide, you will in fact do the same thing you did with splitting the edge, only you can split it many times, and the parallel loop does not go around the entire object, but can if selected (very helpful)!

Sticking Things Together: Merging Polygon Meshes

If you find it easier to create your model from, say, two adjacent mesh-objects you will need to merge them into a single mesh before you export the model. With both objects selected, use Model->Create->PolyMesh->Merge. This creates a new single mesh object in the same place as, and with the combined shape of, the source-meshes. By default, "Merge" also translates the source-mesh texturemaps onto the merged-mesh (sometimes this can make texturing a lot easier). Press "8" to open the scene explorer. Select the sources meshes and press "H" to hide them. Now select the 'polymsh' merged-mesh to freeze and export as your reference.smd.

Finishing Things: Freezing the Operator Stack

In XSI you edit (operate on) a kind of 'editable preview' of your model rather than the actual model itself. XSI records these operations in stacks. When you Freeze the operator stack you effectively apply or save the changes to your model. This means you can no longer undo those operations.

Use Freeze All Transforms & Freeze (or Freeze M):

  • Before applying bones.
  • Before exporting.
  • If XSI is getting slow.

Freeze All Transforms: In order to export your model properly, you must use the Freeze All Transforms (translations, scalings, and rotations) function, which is buried in the context menu triggered by L-clicking the head (title) of the "Transform" panel.

Freeze M: clears the modeling stack, including any weight maps and texture projections that were applied in the modeling region. The Freeze M button lives in the "Edit" panel at the foot of the right hand sidebar. When your model is enveloped, Freeze will also clear weight map, so use Freeze M (Freeze Model changes) instead.

Freeze: (aka 'Freeze entire object') clears the entire construction history, including the modeling stack as well as any texture operator stacks and weight painting stacks. The Freeze button lives in the "Edit" panel at the foot of the right hand sidebar. Freezing removes any animation on the modeling operators (for example, the angle of a Twist deformation, and so on). The values at the current frame are used.

Note:If running XSI with lower than recommended vertical screen resolution, the "Edit" panel can be pushed off-screen by default! To find it, R-click on the head (title) of the "Transform" and/or "Select" panel to minimize them, and the "Edit" panel should become visible ;)

Conclusion

Well, I hope that helped the aching questions you had about all those fundamental differences between XSI and the rest of the world. I sure as hell had a great time writing this tutorial.

Hotkey Reference

o	orbit		Shift + a	frame all
p	dolly		F12	max view
z	pan		Ctrl + Tab	restore
s	navigate		a	frame
l	roll		Alt + Enter	property
			Ctrl + `	close
g	grid		Ctrl + cmd	suppress
r	reset		Alt + 7		texture
q	quick			
				
t	point		8	scene
u	ray poly	3	render
e	edge		6	layer
i	ray edge	7	tree
y	rectangle			
'	tip		Ctrl+Shift + i	invert
=	cluster			
SP	recto		Ctrl + l	cluster
			Ctrl + g	group
v	translate	Ctrl+Shift + g	remove
x	scale			
c	rotate		Ctrl + d	duplicate
m	move		Ctrl + i	instantiate
			Ctrl+Shift + d	extrude
n	poly tool			
			TE	
F7	Rectangle	r		rotate clock
F8	Lasso		Shift + r	rotate count
F9	Freeform	Alt + r		aspect clock
F10	Raycast		Alt+Shift + r	aspect count
F11	Paint			
				RMB
Left	Middle	Right		TE toolbars
X	Y	Z		2D origin

External links