SD HD

HD Chic - Two months old at The Mesa

Cloud Party uses a method of rendering called the SD HD System.

From the wiki (November 2013): 

One problem virtual worlds struggle with is letting users fully express themselves in their avatars while not causing performance problems for other users with slower computers who are nearby. We've come up with a way to address that problem: Standard and High Definition modes for avatar costumes. 

Each costume part will have at most one mesh/material combination that can be marked as 'Standard Definition' (SD). This must be under a certain triangle limit (the limits are defined per slot further down in this document). The other mesh/material combinations will automatically be marked as 'High Definition' (HD). HD meshes have no triangle limit.
SD mesh/material combinations will always be drawn, but HD mesh/material combinations will drop out at a distance. The distance it drops out at will vary from user to user. Some users with low-end computers or mobile devices might never see the HD version of the costume. 

It's best practice to make most, if not all, of your costume piece fit within the SD triangle limits. If you don't, that costume piece will disappear or maybe even never be drawn on certain lower-end machines, even if it's a shirt or pants. We'll be providing tools on the marketplace for users to easily see what they look like in SD vs HD. Also, certain costume slots REQUIRE a SD mesh.

Click for larger version
You will see yourself in HD but others may not.

This is a little difficult to grasp for those making wearable items. So here is what I have learned so far to help you along your creative road.

You can always see what the SD version of an outfit looks like by choosing the SD view in the Costume Creator (inside your cell phone).

SD items can look pretty good but they will never have tons of detail because of the triangle limits imposed. For clothes, you can use textures to fill in those extra touches or make it so they are not so important.


These jeans are one of the nicer items in the default wardrobe. They look good and are very wearable. The top shown here is a SD top (like the jeans no HD version at all) that uses textures to make its fashion statement, not triangles. Both boots and hair are made with both HD and SD versions. Let's take a closer look at those boots.

click for larger version


These are the HD version of my CC Ug Boots. They are pretty spiffy and I am personally very pleased with them. Remember if you are reading this in 2014 or beyond they may not SEEM so spiffy, but at the time they were *wink*.

They use just one texture but I threw caution to the wind and made it a big one as I plan to live in these boots this winter. They also have a normal map (just the fur lining).

They include an alpha mask (definitely needed).


These are the SD version which most folks will see from far away and some with slower connections or less hefty systems may see most of the time.

They aren't BAD, but there is only so much you can do with 500 triangles.

These by the way are ATTACHMENTS and not rigged boots. Rigged boots would share that triangle limit, attachments get 500 per foot in this case.




Making SD HD


When you make your costume items (clothing and wearable attachments) it is best to include an SD version in the slot provided. Otherwise you or your customers go around naked or invisible. Indeed, that IS a mandatory part of the costume scenario in the clothing area -- it is not for attachments as of this writing.

You will need to make TWO meshes (more are possible in the full outfit slot). One will be your high quality, detailed mesh (no triangle limit but let's not go down the subsurf finger tapping mode - shall we). One will be for the simple (very simple) version of your object.

How you make those versions will depend on your work method. Some folks make the complex mesh first and then simplify. I find that in CP I am making the SD versions first, trying them on for fit and then enhancing them for looks and detail. SD items can only have ONE material (texture call from the server). HD items can have as many as needed but unless you are making color change items or something that needs shine etc. it is more efficient to use one material. You could also use masks to define areas.




There is currently a slot to define your SD mesh (where it says "standard definition object"). It has a drop down list with the meshes that are part of the costume (like the left shoe for example).  You will also want to check the box that says Hide SD in HD so that you don't see BOTH versions at once.

Rigged clothing attaches automatically to the correct spot. Hard attached items like these boots are trickier. Practice DOES make it easier and a widget is in the works which should be exceptionally nice for new and casual users (and for content creators too of course).

You will need to attach the mesh to an appropriate bone. There are a few slots like "hat" and "glasses" already defined. Others take some adjusting. You can see from my numbers here.

That's pretty much what I know. Hope it helps.

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