Softimage responded to users’ request with XSI4. Images courtesy of Softimage Co. and Avid Technology Inc., unless otherwise noted.

I. Review: SOFTIMAGE|XSI 4.0

Many of XSI 4.0’s enhancements and features are a direct result of user requests, such as rigid body dynamics, goal based simulation, material libraries, texture layer editor, competitive pricing, mental ray 3.3 Python support, more rendering nodes and advanced UV unwrapping tools. Others were a very welcome surprise, such as vector/raster paint, construction modes, audio tools, custom display host, new XML based interface controls, complementary renderfarm software, character SDK, metashaders, Syflex cloth, Alienbrain support, Digimation support and Avid Mojo support.

1. The Interface
It still looks very much the same, but it now provides many new functions that were previously impossible, such as relational views and a new type of view that contains multiple views that work together as a team. They are very easy to make, as creating these views works much like building a layout for your interface. As an added bonus, the interface no longer hides buttons and controls when it is resized, and it is relatively easy to add commands to the right-click menu as well as the other existing menus. Other relevant novelties are, for example, the support for a dual monitor render window that is now possible to reorder scene objects in the explorer, minimize floating windows and to auto hide the interface. While previous versions of XSI had some ghosting ability, it was nothing like the new ghosting that has been implemented in XSI 4.0. With the new functions, you can ghost just about any animated function: hair, bones, cloth, softbodies, hardbodies, etc. It is tied to the architecture at a very core level and there are many more options that are waiting to be explored. And the custom display host is pretty amazing. It lets you open any foreign application (such as a game engine) in a viewport. This means that a game developer can now run and test the game directly within XSI. You can easily play the game and test it, using a joystick or the keyboard. It is even possible to run another 2D or 3D application within the XSI viewport. XSI layouts have been completely revamped, described in a simple XML file and are now resolution independent. Until XSI 3.5 you could create layouts, but you could not really modify panels. In version 4, you can split horizontal/vertical panels and add several components to it.

Avid’s digital nonlinear accelerator Mojo is a great enhancement. Credit: Britney Spears Toxic by KromA for Jive Records.

2. Modeling
XSI Bevel has been enhanced even more, making it easier than ever to bevel polygons, points and edges; also the beveling of text is now much easier. A new tool called manage collisions makes it a snap to collapse points that collide with each other during the bevel process. There are new “knife” features, which work much like the knife tool in LightWave. One is called knifing and the other is called slicing. They perform the same operation, allowing you to split the polygons of a mesh object along any plane, but the workflow is different. Knifing is an interactive tool that lets you slice polygons by drawing a line in a 3D view. There are multiple new polygon reduction tools in 4.0. The polygon reduction tool can work in symmetry and preserve the volume and the shape of an object. It is also pretty easy to make quads out of tessellated polys. This is done by interactively tuning the settings until the diagonal edges disappear. This tool is great for models that have been imported. The function smooth transition makes edges shrink before they collapse, as the reduction amount is increased and corresponding properties, such as texture UVs and vertex colors, are interpolated. This allows the object to gradually morph when the reduction amount is animated, and avoids sudden popping in the object’s shape or textures as edges collapse.

There are new tools that enable direct manipulate subdivision surfaces. This allows you to select points directly on the subdivision surface as with edges and polygons. There are also two new subdivision algorithms. XSI-Doo-Sabin and Linear Subdivision. XSI-Doo-Sabin smooths the surface in a similar fashion as standard Doo-Sabin subdivision, but has several advantages. When the subdivision surface is subdivided, surface attributes such as polygon colors and texture coordinates are properly propagated to the subdivided surface without distortion or error. Creases can be applied to the object in an intuitive fashion and will give results similar to the Catmull-Clark creases. Linear Subdivision will linearly interpolate the vertices. The only case where this will change the shape is for non-planar triangles. The effect is that each polygon becomes a “rubber sheet”; this will lead to more pleasant behavior as a polygon is deformed. For example: consider twisting a cube. With linear subdivision, the sides of the cube will deform nicely as the cube is twisted. Even if the polygon is planar, this algorithm will affect the texture coordinates — distortion created by the triangulation is reduced, since each polygon is broken up into smaller pieces. The new function Extract Polygons (Delete) allows you to extract from a mesh, make a copy of selected polygons and create a new object with them. Extract Polygons (keep) creates a new object but leaves the selected polygons on the original object. If you want to detach the polygons but keep them in the same mesh, the “Disconnect Component” tool should be used instead. If you want to remove polygons from the original mesh, then “Model> Create>Mesh>Extract from Polygons” should be used.