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Full Quality Texture and Stage

I recently finished a 3D ‘metropolis’ in Papervision, and had a lot of fun doing so, although to be honest – I was rather disappointed with the performance. Given the time frame (just over three weeks) I’ve no doubt there’s room for improvement in my code, but I’d really hoped for more. I should be clear that I’m not criticising Papervision, or Flash – but developers need to be aware of the technologies limitations (I wasn’t) before signing off on a brief . Still, if you’ve already made it that far, below is a list of the most significant performance boosts I used to get past the finish line;

StageQuality; I was horrified about the idea of reducing stage quality – but the truth is, reducing the stage quality whilst a 3D animation takes place is a big plus for the frame rate and hard to spot in terms of quality. Thanks to http://www.julapy.com/blog/ for that one.

Low Texture and Stage Quality

Texture size; If you’re going to use movie clips as textures you should note that performance is directly proportional to the clip size. As with StageQuality reducing texture size whilst making a transition pumps up the frame rate without being noticeable. Another big plus of variable texture quality is the ability to zoom in on a 3D texture without it becoming pixelated. To vary the textures quality I added it to a parent container; this way Papervision can use the scaled width and height without messing up the UV mappings;

…

_textureClip.scaleX = _textureClip.scaleY = TEXTURE_QUALITY;

var bitmapMe : Sprite = new Sprite();

bitmapMe.addChild(_textureClip);

_movieMaterial = new MovieMaterial(bitmapMe, useAlpha, false, false, new Rectangle(0,0,512*TEXTURE_QUALITY,512*TEXTURE_QUALITY));

…

Low texture quality

Animation; The performance hit generated when animating textures is the most significant of all settings – I didn’t use it freely on any of my textures. Instead I enabled animation if and only if the texture had update. The simplest example of this being button rollovers . By animating the texture when the button is rolled over, and disabling again once the movie clip animation is finished you get a big change in overall performance. To this end all of my 3D display objects extended a single class that would call (usually via a timer/enter frame as animations took place);

movieMaterial.drawBitmap();

In the end though I did have a lot of fun with Papervision, Blender and the rest - but next time I tackle something like this I’ll do so with these limitations in mind.