Welcome to Blob Sculptor for the Mac OS, a simple freeware 3-D CAD application for quickly creating 3-D "blob" or metaball objects. What is a "blob", and why would anyone want to sculpt one? As a way to avoid a thousand words, here is a picture of a simple blob, designed with Blob Sculptor MacOS, and then exported and rendered with the freeware ray tracer, POV-Ray MacOS:
This software and the following notes assume that you already know a little bit about what a 3-D CAD modeler is, and what a renderer or ray tracer is, and what blobs are, so we won't cover that ground much here. Well, maybe a quick glossary of terms won't hurt :-)
Glossary
Blob or Metaball: A mathematical surface, described by a field that flows over and envelops multiple components of a complex shape, much like a shape created by pouring honey over a bunch of little marbles. These shapes are not easy to grasp until you play with them a little, don't worry if it all sounds vague and fuzzy for now.
3-D CAD Modeler: A software application that lets you create, move and resize 3-D shapes, using a standard 3-view drafting style display (looking at your work from the top, front, and side.)
Renderer or Ray Tracer: A software application that reads a 3-D file created by a 3-D CAD modeler or other utility (or by hand) and creates a picture/image that looks photo-realistic, with lighting, textures, and shadows.
POV-Ray: A freeware ray tracer written by the POV-Ray Team (http://ourworld.compuserve.com/homepages/povraymac, http://www.povray.org). It is currently available on many platforms, including Macintosh, IBM PC, Amiga, VAX, Cray, Unix, Sun, etc.
Polyray: A shareware ray tracer written by Alexander Enzmann (70323.2461@compuserve.com). It is currently only available for the IBM PC, although a Macintosh version was once written long ago.
RAW file format: A simple 3-D surface file format in text file format, used by some software to exchange complex surface data. It consists of a list of triangle coordinates, one set of triangle vertices per line, which together describe a surface as a triangle mesh. For example, if a Raw file had two triangles, T1 and T2, consisting of the coordinates: T1<x1,y1,z1> T1<x2,y2,z2> T1<x3,y3,z3> , and T2<x1,y1,z1> T2<x2,y2,z2> T2<x3,y3,z3>, then the file would have the following format, with each coordinate number separated by a comma:
DXF file format: Another 3-D surface file format in text file format, invented by AutoDesk (creators of AutoCAD), and used by more 3-D software to exchange complex surface data.
Introduction
You can design blobs in Blob Sculptor's 3-D CAD-like environment, and even get a quick wireframe preview of how the blob components will melt together to make the final blobby object. Finally, you can export your creation to one of several 3-D object file formats (POV-Ray 3, PolyRay, DXF, RAW.) The BlobSculptor file format (".BLB" file) itself is 100% compatible with the MSDOS version of BlobSculptor, so you can read and edit existing ".BLB" files as well.
The original Blob Sculptor application is authored by Alfonso Hermida and Steve Anger on MSDOS, and this is a Mac OS conversion of their original work, with their permission of course.
System Requirements
Blob Sculptor is a "Fat" application, so it runs native on any PowerPC, and on any 68020 or better with a floating point unit (FPU.) Nobody makes anything less than a 68020 anymore, but there are still lots of existing machines without FPUs, so I have included a separate 68020 non-FPU version of the application in case you have one of these computers. Note that BlobSculptor will work adequately on a non-FPU computer, but the preview display will be painfully slow. They both require System 7 or better. Neither QuickTime nor QuickDraw 3D are needed to run this software.
How to Use it
Run the application, and click the OK button to dismiss the splash screen. You have a new untitled Blob Sculptor screen. Like any Macintosh application, this window displays your work, and you can save it to a file and open existing blob files and edit them in this window. You can only have one window open at a time, so you will need to close any open window before opening another window.
In this window, there are three main views and an isometric (camera) view, and off to the side is an information (Info) view.
The Top view gives you a top-down view of the work area. The Front view gives you a head-on view, and the Side view gives you a view from the right side. The Isometric view gives an oblique wireframe (or camera) view, at an angle you can choose. The Info view gives statistics on the blob file, how many blob components you have added, and information on the currently selected component.
A little terminology
Blobs are made up of components, in this case, individual spheres. Each component has an X,Y,Z center position, a radius (or size), and a strength. Its strength tells it how much it will ooze out toward other components. If its strength is negative, it will actually repel the surface of nearby components instead, denting their surfaces away from it instead of pulling them toward it. Positive-strength components are shown in white, negative-strength components are in tomato-soup-red, and the currently-selected component is in yellow. An axis is also displayed in each view. The length of each line is one unit, so for example, the red line along the X axis goes from X=0, Y=0, Z=0, to X=1, Y=0, Z=0.
Adding new blobs
Note: Many of the following commands only work in the main views (Front/Top/Side.)
You can add blob components by choosing Create from the Commands menu, and dragging out a sphere. A shortcut to this is to simply hold down the option key, and drag out spheres.
Selecting a component
Some of the commands we will describe next work on the currently selected component, so you need to know how to select one. You can select a component by clicking on it near its edge in any of the three main views. Once a component is selected, it is shown in yellow, and you can select the next/previous component by pressing the forward/back arrows, or the tab key. You can press the space bar to de-select the component.
Moving
To Move a component to a different spot, select it, then choose Move from the Commands menu, then drag it to another location.
Resizing
To Resize a component, select it, then choose Resize from the Commands menu, then drag out a new radius for it.
Copying
To Duplicate a component, select it, then choose Duplicate from the Edit menu. Now two components will occupy the same spot, and you can see only one. Click on the component to select it, and move or resize it, and you'll see the other one behind it.
Deleting
To Delete a component, select it, then hit the Delete key.
Change Strength
To Change a component's strength, select it, then choose Set Strength from the Commands menu. Positive strength values make the surfaces of components attract each other and flow together. Negative strengths repel, and make the surfaces of components avoid each other.
Change Blob's Threshold value
The Threshold value of a blob sets how blobby the components act toward each other. A larger threshold means that the components need to be stronger or closer to attach, so they "dry up" and don't melt out toward each other as much. Smaller threshold values tend to make the blob larger and more rounded. To change the overall threshold value for the entire blob file, choose Set Threshold from the Commands menu.
Preview the Blob
To see a preview of the final blob in a 3-D wireframe display, choose Preview from the View menu. Choose this again to return to CAD display.
If you have a faster Macintosh and want to see a finer mesh in Preview mode, you can choose Level Of Detail from the View menu, and increase the level of detail. A value of 5 gives a fast but rather inaccurate preview. A value of 20 is slower but gives reasonable results. 50 is very detailed, and rather slow, even on a PowerPC.
Showing Grid lines
To toggle grid line display on and off, choose Show Grid from the View menu.
Snap to the Grid lines
To toggle the "grid snap" on and off, choose Snap to Grid from the View menu. When it is on, components will snap to sizes even with grid lines.
Zoom in/out
To change how close your camera is to the views, choose Zoom in or Zoom out from the View menu. Zoom out moves you away from the center of the views, and Zoom in moves you closer. This affects all the views, including the Preview.
Center a View
Choose Center View from the View menu, and click on a spot in one of the main views. The view will slide over so that where you clicked will now be shown in the exact center of that view. This can be repeated to pan the view around. Changing the center of any one view has no effect on the other two views.
Changing Angle of View
To change the camera angle of the Isometric and Preview views, choose Set Camera Pos from the View menu. You'll see a circle around a small top-down view of the axis.
Click anywhere on the circle, and the black line will move to the clicked spot. This moves the camera to that spot, looking in toward the center. Click the OK button, and you will see the new view angle displayed in the isometric view. If you choose Preview, it too will be shown from this new angle. Currently you can only change the view around the scene, you cannot move the camera up or down. It is permanently fixed looking down at 20 degrees toward the origin.
NOTE: There is a new quick way to rotate the camera around the origin (still looking toward the center) in 10 degree increments. Just press <command>-[ to rotate to the left, or <command>-] to rotate to the right.
Saving your Blob file
To Save your work, choose Save from the file menu, and choose a file name and a spot to save it on your disk. It will be saved as a .BLB file. See the section "MSDOS Compatibility" below if you want to share your blob file with the MSDOS version of Blob Sculptor.
Exporting your Blob file
To write your blob file to some other program's file format, choose one of the "Export to..." items from the file menu, and choose a file name and a spot to save it on your disk. Currently, you can export to POV-Ray 3.x ray tracer scene file format, Polyray ray tracer scene file format, DXF (3DFACE) format, and RAW triangle file format (triangle mesh.) POV-Ray and Polyray support blobs directly, so there is no loss in quality for exporting. DXF and RAW convert the shape into a mesh of interconnected flat triangles.
NOTE: To change how detailed the exported mesh will be for DXF and RAW formats, first change the "Level of Detail" (POV-Ray and Polyray export ignore "Level of Detail", they are high-quality regardless of its setting.) Larger numbers for Level of Detail will create more accurate, finer-meshed shapes. However, this will also increase the number of triangle-facet objects in the exported file, and make the file much larger. This increase in quality and file size could slow down the import, display, and rendering of the shape in the modeler you have imported it into. For example, setting the Level of Detail on a fairly simple 10-component blob yielded the following results:
Level of Number of File Size
Detail triangles KBytes
-------- --------- ---------
10 600 40
20 2588 165
30 5912 370
40 10864 680
MSDOS Compatibility
Note that blob files are usually saved with a '.BLB' suffix on them. It is not necessary to keep this suffix when working with them on the Mac. But you will need to have it if you want to share the files with your MS-DOS friends. Note also in the File menu, there is a menu item called "Use MSDOS Format". If you choose this, a checkmark will appear by it, and any files you SAVE or EXPORT will be MSDOS-format text files instead of Mac OS-format text files. This is useful if you will be using these saved files on MSDOS computers. Blob Sculptor Mac OS can read both MacOS and MSDOS format BLB files just fine, whether the "Export..." menu item is checked or not; That item is only useful for changing how files are written, not read.
Bug Reports
Please use the following form if you wish to e-mail reports of Macintosh-specific bugs or problems. Try to give as much useful information as possible. Please don't e-mail large files... if you must send an example, try to create a very small one that exhibits the problem & attach it (via Binhex) to the bug-report e-mail. Put "BSM bug report" in the subject line, and e-mail it to:
esp Software
CIS: 71513,2161 or
Internet: espsw@compuserve.com
We try to respond to all e-mail quickly, but please be patient... sometimes we get lots of mail!
---------------Fictitious sample filled in, replace with real information ---------------
BSM version: 1.1.MacOS
Name: Sergei Prokofiev
E-mail: NeverCryWolf@neoclassical.sr
Date: 2/10/97
Computer Model: PowerMac 8500
MacOS: Russian System 7.6
Memory: 32 MB, Virtual Memory: off/on/RAM Doubler
Monitor size/depth: 17" millions of colors
QuickTime version: 2.5
Weird extensions: SpeedDoubler, SoftwareFPU, After Dark 4.0
Describe Problems:
1. If I add a couple blobs, sneeze, then delete them, it crashes when I delete the last one (using delete key.)
Legaleze
This package is copyrighted freeware, and all rights are reserved by the respective authors, Alfonso Hermida, Steve Anger, and Eduard Schwan. No portion of this package may be redistributed or republished in whole or part in any form without prior consent of the main author, Alfonso Hermida. It may be uploaded as-is to the internet and to BBSes without such consent; However, it may not be included in disk/CD-ROM collections or distributed in magazines without prior approval from above authors.
Muchas Gracias!
I would like to thank Alfonso Hermida for contributing his code for me to rework into a Macintosh application, Chris Petersen and Diego Krota for beta-testing the bugs out of my work, and Lorrie, Sara, and Bryon Schwan for helping me produce it.
Who do you call?
If you have any comments, questions, concerns, etc., regarding the Mac OS version, please send us e-mail. You can send it to our CompuServe account at: espsw@compuserve.com
which we usually check every evening.
Also, if you want to find the latest version of Blob Sculptor MacOS (or our other products) try our web page at:
<http://ourworld.compuserve.com/homepages/espsw>
The freeware POV-Ray Mac OS ray tracer mentioned above can be found at:
If you have general BlobSculptor questions, you should probably direct them to the original author, Alfonso Hermida: 72114.2060@compuserve.com, or Steve Anger: 70714.3113@compuserve.com
This Macintosh software conversion is brought to you by esp Software, makers of MooVer and POV-Ray/MacOS.
