Forum : Bugs

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Topic: Different points in point clouds

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pope_luke (Over 1 year ago)
I really don't think this is a bug, but it's something I've been wondering about. Practically every synth I encounter has the same kinds of points in its point cloud. Tiny tiny little pixel size dots that only ever have one size.
Every once in a while, though, I see a synth that has bigger glob-type points in its cloud. They seem to be various sizes all around. They're not huge, of course, but they're obviously bigger than a single pixel. I was going to give a link to one synth I just saw them in, but oddly enough it's not there anymore. That is to say, this points have gone back to normal.

It's not like this is an actual problem or hindrance. The synth I saw it on actually had very few cloud points, so the result was actually better than in the normal point cloud, since more felt filled in.

So is this a bug report or a suggestion to use a bug? I don't know. Just wanted to mention that I saw it. And sort of liked it.
douglas (Over 1 year ago)
Hi pope_luke,
  in the viewer we have a maximum resolution we use for the texture we draw all the points to, if you make the viewer larger than this size then we simply scale the pointcloud texture which would cause a single point to cover multiple pixels.  It's not a bug :-)

Mark.
Nathanael (Over 1 year ago)
Mark, I take it that the ability to throw the quad movement on the GPU with Silverlight 3 doesn't free up enough CPU to alter this when you guys release the Silverlight 3 version of the viewer?

If so, will we at least see an increase in the number of points loaded when moving through a synth? I'd like to get back as close as possible to the standard set with the Direct3D viewer. Obviously when you introduce synth linking some sort of clipping or 'draw distance' must be introduced to the combined 'live' point clouds, with the rest being rasterized once movement stops as you currently do on a much smaller scale with the Silverlight 2 viewer, but I'd like to see the number of 'live' points raise back up dramatically to scale to the machine that it's being viewed on.

Cheers,
Nate
pope_luke (Over 1 year ago)
Thanks for that clarification. I guess I'm not sure how I managed to change the max resolution before without knowing it, but now that I know how it works I'm already messing around with it, just to be able to see it differently.
Jonathan (Over 1 year ago)
Nate - SL3 still doesn't let us offload enough of the right processing to the GPU, so we won't be reenabling full point clouds during dragging. It just impacts performance too much.
Nathanael (Over 1 year ago)
Copy that, Jonathan. 

What feature do I ask the Silverlight team to add in Silverlight 4 or 5 to be useful to your team?
Nathanael (Over 1 year ago)
@Pope_Luke If you'd like to experience the same sort of thing with the Direct3D viewer, just set your monitor to a lower resolution.

On that note, Jonathan and Mark, I was wondering if the Direct3D viewer always renders clean to the currently set resolution or if there were a minimum resolution that it would render the pointcloud at and after that point it would simply be scaled down. The reason I ask is that I've been playing with that very thing the past few weeks and when dropped down to very low resolutions it appears that the points are no longer being cleanly drawn to 1 pixel apiece. I was testing it on a CRT so it wasn't a scaling issue on a flat screen.

Just curious,
Nate
Nathanael (Over 1 year ago)
Well, I dig the fact that this version of the Silverlight 3 viewer now generates the snapshot of the full pointcloud at the viewer's current resolution. Great work, guys! One step closer to the Direct3D standard. While I'm at it, I just wanted to say that I think it's great how dragging the pointcloud drifts to a stop instead of just stopping stone dead as soon as you let go of the mouse button. Maybe that was already there in the SL2 viewer but the framerate used to be so low that I honestly couldn't tell. In any case it's much improved.

If anyone is missing the big chunky point from the pointcloud, you can just set your desktop resolution to a low resolution (make sure that it's the proper aspect ratio [shape] for your monitor first) and either change the word 'view' to 'embed' in the address of your synth to use true fullscreen mode or use F11 to enter your browser's fullscreen mode after you fill the browser window with the viewer on the synth's default page.
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