I read on this forum the other day that texture uploading to GPU is slow ...

my question is: just how slow?

can I get away with 3 uploads per second of small-to-average sized bitmaps on older GPU’s?

Context of my question:
I’ve created a 3d textfield, which is basically a plane with a bitmapdrawing of an actual textfield .. it really looks and feels like a ‘normal’ flash textfield because I update the texture on every keystroke, and about 3 times per second to match the caret / text-cursor blinking.

It looks great for me ... but my graphics card is rather good… and I’m unable to test on another system ...

any tips on this? do or don’ts? data on upload times?

I did an example with maybe something like a thousand planes all updating from the same texture and it ran fine. I think the real bottleneck is actually how many times you’re calling bitmapData.draw().

You can view the examples I have here:
https://github.com/robdodson/away-3d-sandbox

Look at the three examples:
LotsOfBitmapPlanes
LotsOfMovieClipTextures
LotsOfTransparentBitmaps

You should be able to just uncomment them in Main.as. Make sure you comment out whatever sketch is already setup to run or else you’ll have 2 running on top of each other.

This is just a personal sandbox so let me know if you have issues getting it to run. In the project properties it might reference a flex project called inchworm. You can just delete that. I have a swc in there which should fill those dependencies.

*edit*
Also you should read David’s blog on building efficient materials and geometries: http://www.derschmale.com/2011/07/25/building-efficient-content-in-away3d-4-0-sharing-materials-geometries/