Worn Edges

Copyright (c) Christoph Brachmann, Benjamin Walther-Franks, 2006/2007


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Download Version Release Date Description
Worn Edges Plugin for C4D R12 0.3 2011-03-04 updated for C4D R12
Worn Edges Plugin (current) 0.2 2007-09-19 bugfixes
Worn Edges Plugin 0.1 2006-11-08 initial release

What is Worn Edges?

Worn Edges is a plug-in for Maxon Cinema 4D (Version 9.6 or higher) on Microsoft® Windows® and Apple® Mac OS X®. It modifies the geometry of given 3D objects by cutting chips into exposed object edges so that edges appear to be worn and dented.
  • The outline of edge chips added to the objects is based on 2D splines which can be specified or generated by users.
  • The selection of edges to be worn is based on the degree of exposedness.
  • After the geometrical modification a specific material can easily be assigned to the chip surface.

Legal Stuff

This software is not in the Public Domain. Contact the authors {cbrach (at) uni-bremen.de, bwf (at) tzi.de } before redistributing this software via Internet servers, CD-ROMs, etc. Use this software at your own risk. The author cannot be held liable for any damage. There is no warranty (neither explicit nor implicit) that this software will fit any certain purpose. This software has been developed for scientific research; commercial use may violate patents or other rights of third parties. All trademarks are property of their respective owners.

Installation and Use

Installation

Copy the folder "wornEdges" into the plug-in folder of Cinema 4D. Restart Cinema 4D if it is already running. To uninstall the plug-in simply delete the folder "wornEdges". Worn Edges runs as a generator plugin and can therefore be found in the Plugins menu. Just click on the corresponding menu item in order to insert a Worn Edges instance into your Cinema 4D scene.

Showing how to insert an object into WornEdgesWearing an Object

In order to run properly, a Worn Edges object requires two children objects in a specific order: The first one is the 3D object to be processed. The second one is a Null object ("Chip Splines") containing spline objects that provide the outlines of the chips produced on object edges. By generating an instance of Worn Edges, the Chip Splines object is already provided along with sample spline objects. For modifying or generating new spline objects, please read the corresponding instructions below.

For wearing an object, insert any 3D polygonal object as the first child of a Worn Edges instance. For every chip, the plugin tries to combine two consecutive children objects of Chip Splines to form a chip. If it fails, it proceeds with the next pair or starts from the top again. In order to get any worn edges, make sure there are any object edges that are
  • exposed, i.e. the angle between the adjacent polygons is higher than 60°
  • long enough, i.e. longer than the shortest X-length of the splines in Chip Splines
  • made of regular geometry, i.e. every polygon edge has only two adjacent polygons
Note that an object edge to be processed by Worn Edges is not neccessarily equal to a polygon edge. An object edge can be made of several polygon edges. The plugin internally groups connected edges with similar properties into object edges.

Using Parameters

Chip Scale (default: 1.0)
Defines the scale of all outlines in Chip Splines object applied to the chips cut into the 3D object.

size=0.4 size = 1.0 size=1.7
left: 0.4, middle: 1.0, right: 1.7


Chip Scale Variance (0.0)
Defines the range within which the chip scale may deviate from the parameter set in Chip Scale.

variance =1.0 var = 0.7
left: 0.0, right: 0.7


Chip Depth (0.5)
Defines the depth of newly created points within the chip surface relative to the original surface.

depth 0.0 depth 0.5depth 1.0
left: 0.0, middle: 0.5, right: 1.0


Chip Distribution Variance (1.0)
If this parameter is set to 0.0, all chips are placed in the middle of the corresponding object edge. By increasing this parameter, the position will vary for every chip.

distr0 disr 1.0
left: 0.0, right: 1.0


Random Seed (7)
This is the random seed for all calculations of random numbers within Worn Edges. Use this in order to vary the whole selection of edges to be worn.

random7 random8
left: 7, right: 8


Number of Attacked Edges
(1)

This parameter sets the number of chips produced on the destination object. Note that the plugin stops adding further chips if it failed to create one, so the number displayed does not neccessarily correspond to the actual number of created chips.

nr1 nr12 nr24
left: 1, middle: 12, right: 25


Set Chip Outline Phong Break Edges (selected) / Set Chip Surface Phong Break Edges (not selected)
These checkboxes set the Cinema 4D Phong Break edges on the outline of the created chips and for the edges within the created chips, respectively.

00 01 10 11
1. outline surface not selected, 2. outline not selected, surface selected, 3. outline selected, surface not selected (default), 4. outline & surface selected


Chip Outline Point Max Distance (2 m)
This parameter sets the maximum distance between two adjacent points along a chip outline. In case a Chip Spline causes a bigger distance between any two adjacent points, the plugin automatically will calculate intermediate points. This parameter can be used to produce a higher resolution polygon grid within the created chip surface.

maxdist0.5 maxdist2.0
left: 0.5 m, right 2.0 m

Modifying Chip Splines

When generating a Worn Edges instance a set of spline templates is already provided within the Chip Splines object but it is possible to remove or to modify the provided Chip Splines. Furthermore, it is also possible to create new spline templates, however, by regarding the following guidelines:
  • For now, only Linear Spline objects are allowed as spline templates.
  • The z-values of all points are disregarded by Worn Edges, so the best way to edit a spline template is to work within the X-Y-View ("Front") and to set all z-values to 0.
  • The first point position must be set to (0, 0, 0).
  • The last point position must be set to (x, 0, 0).
  • All y-values of the spline points in between must be equally signed, i.e. either they all are positive (above x-axis), or they are all negative (below x-axis). This makes it easier to create a pair of two spline templates that will form one single chip (see fig. below).
spAB
In the first screenshot all spline points have positive y-values ("Stone 01a"). This spline is mapped onto the right side of the destination edge because it is the first spline object in Chip Splines.

spBA
The second screenshot displays a spline template with negative y-values ("Stone 01 b") which is mapped onto the left side because it is by default the next element after "Stone 01 a" in the ChipSplines object.

chip
In the end both splines form the chip outline as shown in the third screenshot.

Working with Selections

After applying the function "Make Object Editable" to a worn object the plugin provides two selection tags: one selecting all newly created chip polygons, and the other containing all modified old polygons. These selection tags allow an easy way to assign different materials to 'old' and 'new' surface of the object.

showing how to use selection tags

Troubleshooting

The following points may help solving problems with the plugin:
  • The default Cinema 4D Cube should work with a default Worn Edges instance, otherwise the installation was not successful. Please check if you work with Cinema 4D, ver 9.6 (or higher).
  • Check if any edges of the destination object are exposed, long enough, or geometrically irregular (see also section above "Wearing an Object").
  • Reduce Chip Scale, as maybe the Chip Splines are too big for the edges of the destination object.
  • Reduce Chip Outline Max Distance as it makes the plugin operations more precise. But be careful, it also increases the computation load!