strata studiopro 2.5

Strata has just released Studio Pro 2.5 and it's now available for both the Mac OS and Windows NT. On the Mac side you will need a Power PC® processor with at least 64 megs of ram (20 for Studio Pro itself and 40 for the system with either OpenGL or QuickDraw 3D) and you had better have a lot more if you intend to do anything with it. On the Windows NT side a Pentium® processor and lots of RAM plus an OpenGL card will make you a happy camper.

So what's new? Well, the implementation of the Conix OpenGL libraries on the Mac for one. I'm using StudioPro 2.5 on a Starmax 4000/200 without an accelerator card and 160 megs of ram at work and at home I'm using it on a 9600/270G3 (newertech card) with 320 megs of ram and ATI's Xclaim3d QD3D card. On both machines OpenGL is fast although it's snappier on the 9600/G3 - even though the QD3D accelerator card does not work in the current implementation of OpenGL. The Conix OpenGLRaver library is available which theoretically should allow the ATI card to work but I found it gave me redraw problems.

Figure 1 above shows a screen shot of the OpenGL flat shaded (camera) view in the Macintosh version of Studio Pro 2.5

Also new is the implementation of true mesh-deforming bones; and on the Mac, bit maps can be pasted into shapes windows from Photoshop for modeling. The bezier pen is improved and now shows control handles in contrasting colors to bezier points (figure 2).

Bezier curves can now be joined together but only as you are drawing a new line - you can't select two already formed curves and meld them into one. A bezier curve can't be divided into separate lines either. Also, one can't change the direction of bezier curves in reshape mode (figure 3).

This should be implemented. It is often necessary to change curve direction - when using the hull tool or when skinning curves together - to avoid odd crimps in your model and until this change is implemented irksome work arounds, like resorting to Illustrator® to create curves, are necessary.

Items can now be deleted from the Project window and key frames can be selected, duplicated and deleted and the text tool can now handle Type 1 postscript fonts as well as Truetype fonts. In general the text tool seems to work more consistently than in earlier versions but there are problems with some letter combinations.

Generally, Studio Pro 2.5 is snappier and more solid. I have had it crash with inexplicable errors and once it refused to open a model with a cryptic 'cannot complete request because of an error' message but the problems have been rare. Some people have reported type 2 and 3 errors but I haven't experienced any of those.

So what are the big problems? Well, the implementation of UV mapping is still inconsistent and to my thinking dismal - especially considering the siren-song of mesh-deforming bones. It would be nice if a complex mesh could accommodate a single UV map but in my experience UV maps are repeated across a complex polygonal mesh without any sensible control what-so-ever. In its current implementation it is impossible to design a UV map which will texture a polygonal mesh. Also, unless the texture map is applied after the bones have been attached to the mesh, only one texture map (regardless of mapping method) can be applied to the mesh. The other mapping methods are not suitable for texturing meshes deformed by bones since they creep over the surface as the mesh is moved through space. Figures 4 and 5 show this behavior.

Figures 4 and 5 above show two polygonal IK-mesh objects that have the same texture map applied. The mesh on the left is has the texture cubically mapped and the one on the right has the texture UV mapped. They are both being controlled by the same IK object. The dark artifacts (after deformation - figure 5) are a consequence of the model's low polygon count but despite this, it is quite clear that the UV map is deforming correctly while the cubic map is not.

A nice feature of the bones implementation in Studio Pro 2.5 is the ability of a single IK object controlling multiple meshes. Also, a mesh can have more than one bone structure linked to it. Bones can also be used to model objects. If a polygonal mesh is deformed with a bone structure and then unlinked it will retain the shape that the bone structure gave it.

Of the final rendering options offered by Studio Pro the scanline renderer is the most problematic as it calculates shadows incorrectly and low resolution objects are not correctly smoothed. Also, scanline renderings tend to be darker in tone than those done with either the raytracing or radiosity rendering engines. The following figures (6,7,8 and 9) illustrate these problems.

Figures 6 and 7 compare shadows generated from the same model using the scanline and radiosity rendering methods. The raytracing and radiosity rendering methods result in similar shadows with radiosity giving soft shadows and inter-object lighting effects.

Figures 8 and 9 compare images generated from a low resolution primitive sphere using the scanline renderer and the radiosity renderer.

I mentioned before that the text tool had some anomalous behavior. While it is definitely improved from earlier versions - allowing the use of Type 1 Postscript fonts for example - there is one interesting problem that figure 10 illustrates.

In figure 10, a single text object (aa) was created and duplicated 33 times. Then in the object palette for each separate instance the characters were changed with the results shown above. It is clear the 'i' and 'l' have the most problems but all of the letter combinations show some aspect of undesirable behavior. Some letter combinations are too short and some are too big and the aspect ratio of many combinations is skewed. This behavior is exhibited by both Type 1 Postscript and Truetype fonts.

Figure 11 above illustrates the behavior of Type 1 Postscript and Truetype fonts. The text on the left is Type 1 Postscript and that on the right is Truetype. The illustration shows a work around for the problem: that of starting your word that begins with an offending character (such as the 'i' shown above) with a period. The period is then deleted from the text object when it is converted to another geometric form. What isn't shown here is the change in size when this work around is implemented. Both 'ipple' and '.ipple' were scaled down after their creation to fit with the original word 'apple' above.

Boolean operations can still give problems with the tools forgetting their function and/or performing different and unexpected Boolean functions but overall this is Strata's best implementation of Boolean operations yet - there is still room for improvement and given their unpredictability I can't recommend them for complex modeling.

Overall I think the upgrade from 2.1.1 to 2.5 is worthwhile if only for the improvement gained by implementing OpenGL on the Mac. The implementation of mesh-deforming bones is clean and in my hands works flawlessly. Mesh points are automatically assigned to bones when the bones are attached to the mesh but they can be reassigned easily with the reassignment tool. I was able to bring a poser figure into Studio Pro 2.5 as a dxf-object and assign a simple skeleton to the model and have it puppeted in less than 30 minutes. Figures 12 and 13 show the results.

Postscriptum: After writing this article Strata released an update to 2.5 that brings the version to 2.5.2. This update fixes a few minor bugs and adds stability but it has had no effect on the various problems illustrated in this article.


Tom Babcock was trained in biochemistry and music and now makes his living doing art and animation for a small company in Berkeley, California. He can be reached at tbabcock@AOL.com.

[ galleries | archives | downloads | about | contacts ]
[ back to main page | back to contents page ]