In this tutorial, you will learn some tricks to make your sculpties looks better at a distance, including the “shrinkage” trick.
LOD Can Kill
As you already know, sculpted prims switch between three resolutions depending on your camera’s distance from them in Second Life.
Sometimes the difference in resolution makes such minor differences in the sculptie that you can simply ignore it. However, sometimes the lower LOD levels end up looking bizarre, or you may simply want the sculptie to retain its resolution better.
The sculpties in the image above were all the same mesh in Blender, but the sculpt map image was changed to effect how the the resolution held up at different distances. The screenshot was taken with Object Detail in SL’s Preferences turned almost all the way down.
Before I get into more technical tips and tricks, I want to remind you about the multires feature in Blender. I had you learn about that for a better reason than just to annoy you. Multires corresponds with Second Life’s LOD (Level of Detail) rendering.
If you start off modeling at the 8×8 resolution (level 1) then your sculptie will have a better chance of retaining it’s basic shape. At the 16x 16 resolution, you should try to include as much detail as you can. The 32 x 32 resolution should only add the most nit-picky details.
If you don’t remember anything about multires, go back to the multires tutorial and read up.
Often you can make the decreases in resolution less noticeable by using a high-quality texture on your sculpties. Baking on shadows, for instance, helps to visually define a form, which will make your object appear to be higher resolution than if you were relying on Second Life’s realtime shadow rendering.
To learn more about texturing sculpts in Blender, read this other tutorial.
There is a more technical trick that will actually help keep your sculpt’s shape at greater distances.You can shrink them.
I don’t mean in SL. In Second Life, you’ll actually be making them bigger.
You see… the distance at which your sculpt loses resolution is relative to how large the sculpt is. The larger the sculpt, the farther away your camera can get before it loses resolution.
So, what we want to do is make the sculpt larger, but make it appear to be the same size.
Yeah, I know. Weird. But it can be done. You’ve probably seen sculpts that do something like it. Several of the freebie sculpts floating around don’t quite fit inside the bounding box when you scale them. Have you noticed? You can stretch and stretch these sculpts, but they they never seem like they stretch far enough! Well we’re going to do this on purpose.
The new Primstar scripts allow you to shrink your sculptie when you bake the sculpt map. When you bring up the Bake Sculpt Meshes dialog, you’ll see a box on the right marked “Range.” The default values for each color value (or axis) are 0 to 255.
What you want to do is increase the values on the left and decrease the values on the right by the same amount. I chose to increase the left values by 55 and decrease the right values by 55, because those numbers are easy to figure out. (I’m lazy.) The larger the difference between the original values and the new ones, the more your sculptie will shrink.
Image Editor Method
You can also do the same thing with some sort of image editor like Photoshop and decrease the color contrast. Some experience in Photoshop is recommended, because I’m going to describe how to do things in Photoshop, since I have practically no experience in any other image editing software.
Open your sculpt map in your image editing application. In Photoshop, the next step is to go to Image > Adjustments > Levels. Ignore Input Levels. You want to change Output Levels, and it needs to be changed by the same amount on both sides. The default values are 0 and 255. Once again, I usually change mine to 55 and 200 since those are easy numbers to figure out. And still. the greater the difference in the new values from the default, the more your sculpt will shrink. Once you’ve decided on your values hit ‘OK.’ Your sculpt map will look slightly greyed.
In some programs, you can use Brightness/Contrast and decrease the contrast, but this is less precise, and it doesn’t seem to do the same thing in Photoshop at all.
Upload your sculpt map and apply it to a sculpted prim. You’ll see it shrink. If you have the original sculpt uploaded, try placing the two next to each other, and stretching your shrunken sculpt so it looks the same size as the original. Then zoom out and watch how their resolution changes.
A Word of Warning
Although this is a neat trick, you can decrease the contrast on the sculpt map too much.
First of all, if your sculpt is not made phantom, the collision box will be as large as the bounding box, not the shrunken sculpt, but also, your sculpt can become deformed.
The image on above shows the same set of sculpts as the first image on this page, only with the Object detail in SL’s Preferences turned to Mid. Notice that the first two sculpts look identical. The third is slightly more choppy looking, and the fourth, obviously, is rather deformed. Below is what the sculpt maps look like:
The less contrast there is, the more values start to run into each other and the more choppy your sculpt will be. If you’ve done a good job with multires and texturing, there usually isn’t any reason to even get as shrunken as the third sculpt. Remember to use this trick wisely. Only when you absolutely need it, and only to the degree it’s needed.