Prim.Blender: Sculpties

MrGomez — Tue, 15 Jul 2008 22:07:37 +0000

(The following is an ongoing series of tutorials for my offline builder tool, Prim.Blender. For the tutorial index, click here)

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Sculpty editing is more than a little weird.

A sculpty, or sculpted prim, is the brainchild of Qarl Linden, though the practice he uses has been suggested before.

Think of sculpties as elaborate origami; you’re given a surface with 32×32 faces to fold into any shape you please. These “folds” are then saved as an image file, where each color’s RGB data represents a direction: red for X, green for Y, and blue for Z.

If I just lost you, don’t worry: making them is easy with the right tools.

Such as, say, this one!

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Sculpties are a relatively new addition to Prim.Blender, after nearly three years of builds (!). I have, however, strived to make working with them as painless as possible.

Sculpties in Blender are tied directly to mesh editing and Blender’s “sculpt” mode. The basic idea is to grab and manipulate the surface of the sculpted prim, then save (bake) it as an image file for use in SL.

Just so we cover everything, Edit Mode looks something like this:

And Sculpt Mode looks something like this:

Yoink!

Most of the tools are fairly self-explanatory: right-click a few verts in edit mode and move them around (G Key + mouse), rotate them (R Key + mouse), or scale them (S Key + Mouse).

Or, go into Sculpt Mode and use the Sculpt button (left of circled) and Blender’s fine sculpting tutorials to create most shapes you can imagine.

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From the interface pictured way at the top, you’ll see all of the standard UI components seen in SL. However, you will also see a bunch of foreign buttons that might not make a whole lot of sense at first glance:

For starters, what the heck are these buttons?

Number of Wrapped Faces? Multires? Sculpt type? There aren’t such things in SL’s sculpties, are there?

Actually, Qarl’s implementation of sculpties supports all of these things in one capacity or another. It’ll become more clear after a bit more exposition:

Number of Wrapped Faces: Describes the minimum number of faces to use for this sculpty, in the X and the Y direction. Because sculpties are elaborate origami, this describes the number of creases you can create in each direction before fancy tricks like Multires (explained below).

Multires: Adds additional levels of detail to this sculpty, in addition to the values described above. This is tied directly to the level of detail slider, and lets you inspect what Second Life™ will do to your sculpty when viewed at varying detail levels.

Sculpt Type: A bit of smoke and mirrors that is hidden away from the in-world tools. Sculpties may be created in four different ways: with no merged edges (plane), one merged edge on the top (torus) or the side (cylinder), or two merged corners (sphere). In addition to these options, several different shapes may be created from the “base” type.

If this is all gibberish to you, don’t worry: the defaults and randomly pressing buttons works well enough for most purposes.

The only important thing to remember is the highest available level of detail will be the one used when creating the sculpty map. To avoid unexpected results, make sure to inspect your sculpty at this setting before baking (hint: it’s the Level of Detail slider).

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Now that we have those covered, how about those other buttons just below the sculpty image?

Those, at least, are a bit easier to explain:

Bake: Lets you bake the sculpt map for this prim. This lets you inspect and manually save the map, if you’re into that kind of thing. This is done automatically when you save, for all sculpties.

Load Texture: Lets you load a sculpt map as a texture. Should not be confused with the texture attributes of this prim. (Note: In future revisions, this has been renamed “Load Sculpty”)

Neither of these options should ever be required, unless you’re working with other tools (like Domino’s), or just happen to want extra control over your sculpties.

However, in releases at or beyond Prim.Blender 0.6.0, you may use sculpty loading to load a series of default shapes, found in the PrefMaps folder of each release.

These shapes are given by type: tsph for sphere, tcyl for cylinder, ttor for torus, and tpla for plane, and are included as starting points for various advanced shapes.

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That covers the basic explanation. Hardcore sculpty geeks can stay for all the details; everyone else should move on to texturing or importing.

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Caveats

Face values are limited to powers of two, from 4 through 32. This is done to make building as seamless as possible, and prevent any “weird” texturing or multires errors.

Values that do not add up to 32 faces on a side (the number of faces in a sculpty) will follow the shape of the current faces.

Multires is capped at +2 levels, because this should be way more than is sufficient for testing level of detail changes in the SL viewer.

Multires only works in Blender 2.46+; all other versions allow the slider, but ignore its value.

Multires is turned off at a value of 0, for purists that just want a sculpt map to mess with.

At the time of this writing, sculpties that are copied are treated as separate, instead of sharing the same image file (as in Domino’s implementation). If enough demand for this feature is present (email me or comment here), I may add the ability to create “groups” that share the same map.

A “sculpty library” of shapes has been added to releases of Prim.Blender 0.6.x and above. If you have ideas or suggestions for shapes to add to this library, email them to me and I’ll offer full credit.

The sculpty code in Prim.Blender is originally based on Domino Marama’s scripts, but may deviate significantly from his design, as my version represents a fork (or perhaps a spork) of his code. Furthermore, he and I exist within two very different paradigms for building with Blender.

Sculpty image sizes in Prim.Blender should always be 64×64. This is the rough minimum for retaining full sculpty detail, while being entirely usable in paint programs, and addressing certain averaging and compression bugs.

The “pixelated” effect exhibited by baking is intentional. This is the “compressible image” fix, first suggested by Aminom Marvin and implemented by Domino Marama. It is also used in mirroring.

All images are automatically saved as .tga. Sorry. Blender is anal about that, currently.

Duplicate images (ie, sculpties that are *exactly* the same) will be culled. This results in far fewer texture files to upload, making the process cost a whole lot less.

Occasionally, Blender will save images as Targa files that aren’t 24 bit. This will be noticed during bulk uploading. In these cases, please manually save the file as a different type, or change its pixel depth to the correct value.

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If you have suggestions regarding my design or documentation, please email me.

Prim.Blender.Importer posted

MrGomez — Sat, 05 Jul 2008 04:01:31 +0000

The importer for Prim.Blender has been posted to Sourceforge, as well as the source section of this site.

Built copies are available here:

http://slurl.com/secondlife/Great%20Pubnico/23/71/93/

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Happy 4th of July!

(Even if it’s technically the 5th on the server’s clock)

Prim.Blender 0.5.0 Release!

MrGomez — Mon, 30 Jun 2008 10:30:37 +0000

I’ve released another copy of that wonderful, crazy building tool for Blender! With Sculpties!

It can be found on its SourceForge page:

https://sourceforge.net/projects/primdotblender/

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I’ve also posted its code to the Source section.

Yay!

Mirroring Sculpties in ImageMagick

MrGomez — Wed, 18 Jun 2008 04:35:15 +0000

Here’s a quick building tip I find particularly handy for mirroring sculpties along a desired axis or axes in bulk:

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* Along the X-axis:
- convert -channel Red -negate -flop

* Along the Y-axis:
- convert -channel Green -negate -flop

* Along the Z-axis:
- convert -channel Blue -negate -flop

* Along the X- and Y-axes:
- convert -channel Red,Green -negate

* Along the Y- and Z-axes:
- convert -channel Green,Blue -negate

* Along the X- and Z-axes:
- convert -channel Red,Blue -negate

* Along all axes:
- convert -channel Red,Green,Blue -negate -flop

Example:
convert -channel Blue -negate -flop rook_source.png rook_dest.png

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This is a command-line operation for ImageMagick.

… and works in Cygwin for Windows, Terminal.app for OSX, and your favorite terminal for Linux/BSD.

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If you’re not comfortable with these options, the same effect can be emulated in Photoshop or The GIMP by flipping your image horizontally and inverting the Red (X), Green (Y), or Blue (Z) channels for the desired effect.

These operations may be combined, but you must flip the image horizontally each time you use an axis of rotation. (that is, once for X, Y, or Z, twice (no change) for XY, XZ, and YZ, and three times (once) for all three axes)

Anyway, I figured that’d be a handy little tip and timesaver.

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PS: Support the JIRA thread for mirroring sculpties in the viewer:
https://jira.secondlife.com/browse/VWR-6682

Forum Link: http://forums.secondlife.com/showthread.php?t=265631

Half Past Null » scupties

Prim.Blender: Sculpties

Prim.Blender.Importer posted

Prim.Blender 0.5.0 Release!

Mirroring Sculpties in ImageMagick