Modeling

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Primary modeling of Project Widow is complete, only various objects remain to be created or edited.

Quad Polygons

The reason for using Quad polygons rather than triangle polygons is more related to the rendering end. When Aqsis (or any RenderMan renderer) begins to render a bucket, each polygon is diced up into microploygons, which each are about a pixel size, then these micropolygons are displaced and shaded using the shaders assigned to it.

It is actually far more efficient to use Quad polygons than Triangles because of how the REYES works, since it does slice up the geometry there is less work the renderer needs to do with a quad as it is an even distribution of micropolys. With triangles, there is more work involved as the dicing process needs to figure out the best way to do this, as triangles are an odd number of vertices there is no even distribution of micropolygons.

There will be instances where triangles are unavoidable, Aqsis CAN handle triangles, it just would take a little more time to render rather than with quad geometry.

Regardless of what type of polygons used, high poly count models will increase render times. Sometimes this is not possible to counter and for the most part we have tried to keep this as low as possible.

Subdivision Modifiers

When modeling objects in Blender keep in mind that objects do not need to be highly detailed geometry in order for it to render as such. In other words, depending on the object it is far easier for both the artist and Aqsis to keep it as simple as possible. Walls, floors and ceilings do not need to be more than a few polygons if they do not have to, though it may require a SubD modifier applied to them in order to prevent what is known as "grid cracking". The objects that require a fine edge while still remaining smooth will need some editing in Blender to crease right. Using best judgment on poly count is essential when applying SubD modifiers to objects, if one were to visualize what Aqsis "sees" when it renders a SubD sphere you could turn up the Level to 4 and that would look similar for instance. While in the literal sense this is NOT how Aqsis dices up geometry, that is something for modelers to remember : more polygons does not mean better. In many cases more polygons means that Aqsis has to work harder at something it doesn't need to.

Quad geometry is ideal for this as it is much easier for Aqsis to dice up, rather than triangle geometry. Sometimes it is not possible to do so, in which case make the best of it. In those cases using Aqsis to preview the mesh should be important, as opposed to the Blender Internal renderer which is designed to handle the geometry generated in Blender (obviously).

Aqsis can handle any geometry thrown at it, even things not FULLY exportable from Blender (such as NURBS surfaces which in that case it exports unpredictably and not accurate at all).

Preview using Aqsis

It might be a good idea to use Aqsis to make periodical preview renders in case there is something wrong with the geometry, sometimes it is possible that faces are not built right for Aqsis to dice up (or most RenderMan software). Sometimes this can result in cracking, which looks very bad in the final renders and can be a huge pain to fix later on. Though in case it does happen and it might happen when you least expect it, make note of it and we will try to correct the geometry issue in Blender. Sometimes it won't show up until later, or at a camera angle different than what you were using for modeling. Try to do preview renders at ALL angles to avoid such complications later in the process.

Materials

When modeling an object make sure that Blender materials are assigned to geometry that has a different look than other parts of the geometry, such as if there is half one type of Material that is to be a metal look to it and another Material that has a dirt look to it. This will save a LOT of time later on when doing the shader and texture process, especially with complex geometry. It is not required to make separate objects in Blender for each type of Material, though if you do decide to do so make sure it is Parented so when moving them around these objects remain in place. The reason for a Material assignment is so that later on there is not a complication when changing custom shaders or textures, it just makes the rest of the process smoother to complete.

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One of the advancements made in recent years with Blender to Renderman exporters is the individual Material per Poly in Mosaic. With previous plugins it was simply not possible to assign Blender Materials to individual polygons and render them. The shader was bound to the Object, not the Material in Blender. With Mosaic this has changed and it is possible to have multiple materials per object, this it is possible to have multiple Renderman shaders per object. This dramatically helps the shading process plus it is far easier to reassign these polygons to new Materials. In the end this means that a smoother and faster shading stage, not to mention beautiful renders.

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