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Wow. In Papervision3D, the function to replace materials on a cube I’ve mentioned earlier also works on Collada models, which I wouldn’t have expected. Considering how well implemented Collada is (in all engines I’ve tried), I was seriously expecting that this isn’t possible. But it is. Just be sure to get the right material name and it works like a blast. Collada files are XML-based, so the name can be traced rather quickly:

<library_materials>
   <material id="_1_-_Default-material" name="_1_-_Default">
     <instance_effect url="#_1_-_Default"/>
   </material>
 </library_materials>

It’s the id, not the name. You can also trace it from AS3 with:

trace(dae.materials);

, which is surprisingly simple. Replacing it works the same way as with a cube:

dae.replaceMaterialByName(material, "_1_-_Default-material");

I suppose this was especially easy because I used a UV-Mapped model with only one material, but it should work the same for models with multiple materials.

I’ve taken a look at Away3D again, because I had a problem in PV3D, which was so stupid I couldn’t believe that it could actually be a problem. However, as expected, Away3D isn’t exactly free of problems either: If you place 3D objects on a website it might be necessary to display them precisely 1:1, without distortion. That’s especially important if I want to place text or small bitmaps on the objects, as e.g seen on the temporary TCM splash page. In Papervision3D the setting is:

Object.z = Math.round((camera.zoom * camera.focus) -Math.abs(camera.z))
           + Object.depth/2; // take or add 0.5 if it's still blurred

In Away3D the major solution is to place the surface 900 pixels away from the camera, when using default camera. Why 900? I have no clue, but who cares, it won’t persist through changes of the camera anyway. Even worse, it’s not even giving proper results… I’ve spent quite a while testing it and there’s always artifacts and distortions:

I know the image isn’t friendly to the eyes, but it shows the problem quite clearly. The top right one is the original that I used as a material. Weirdly, the bottom left pixel corner is cut and one pixel line in the middle of the plane is duplicated horizontally and vertically as soon as you place it on an object (a cube, in this case). Adding segments or turning on precision doesn’t change anything. Adding / subtracting 0.5 from the coordinates shows parts of the cut corners, but the opposite sides get blurry. Adding smoothing to the material, as some suggested, isn’t a solution either. I suppose this isn’t a mere problem of not having tried enough, because there were others who had this problem before, with no solution. Maybe it only works for planes and not cubes? Well, at least up there’s the setting to get it almost correct.

I’ve quickly checked Hidden Heroes, which was made with Away3D, to see if those ingenious guys fromGGH have found a solution… but it seems that they’re also just switching between blurred and distorted 3D-Planes and normal 2D MovieClips.

Meh. I’ll keep looking.

Annoying. If you have objects with child objects and put addEventListener(MouseEvent.CLICK, mouseClickEvent); on it,

function mouseClickEvent(e:MouseEvent):void
{
trace(e.target.name);
}

will trace the child objects instead of the parent. I’m not exactly sure why that happens, but putting MovieClip.mouseEnabled = false; on every child object helps (which was OK in my case).

Found here: http://www.communitymx.com/blog/index.cfm?newsid=895