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>> The new mesh will consist only of quadrilaterals, which won't in general be flat.
Could someone clarify this?
Does this sentence mean:
"The new mesh will consist only of quadrilaterals. Each quadrilateral won't in general be flat."
or
"The new mesh will consist only of quadrilaterals. The mesh won't in general be flat."
isn't the image wrong? A cube shouldn't become a sphere with catmull-clark! âPreceding unsigned comment added by 85.225.115.25 ( talk) 19:15, 30 December 2007 (UTC)
The weights (n-3)/n, 2/n and 1/n are definitely not the ones used in the images. K-3D uses (n-2)/n, 1/n, 1/n. Similarly every other illustration on CC SubD uses this set of weights. Here are two movies showing the different Subdivision stages: (n-3)/n, 2/n and 1/n: http://dl.dropbox.com/u/281539/jReality-CC.mov (n-2)/n, 1/n and 1/n: http://dl.dropbox.com/u/281539/jReality-CC-2.mov
Clearly the method with (n-3)/n causes the weight to vanish for valence 3. Hence the old vertex has no impact whatsoever in the new location. While there are other approaches to handle extraordinary vertices, they usually result in less "round" edges because they give a larger weight to the old location of the vertex during the move stage. â Preceding unsigned comment added by Moritz Angermann ( talk ⢠contribs) 16:17, 8 March 2011 (UTC)
>> and take the average R of all n edge midpoints for edges touching P, where each edge midpoint is the average of its two endpoint vertices
Can someone clarify this? Does this mean the endpoint vertices from the original edge or the new edge? Broodle ( talk) 02:47, 28 April 2008 (UTC)
I propose deleting the section "Software using CatmullâClark subdivision surfaces". It is not especially interesting for an encyclopedia, and it is highly unlikely that this list will ever become all-inclusive. For the moment it is just getting long enough to become a visual distraction to the encyclopedic content surrounding it. -- Berland ( talk) 09:30, 14 August 2008 (UTC)
I find this section rather difficult to understand. A few graphical masks would be of much more help than "face point"/"edge point"/... (btw: are you sure it's correct or do I still not understand it? :) Is an edge point really the average of all neighbouring face points? (I thought the points were only dependent on the original pts?) âPreceding unsigned comment added by 91.19.90.230 ( talk) 13:49, 21 October 2008 (UTC)
This article has not yet been rated on Wikipedia's content assessment scale. |
>> The new mesh will consist only of quadrilaterals, which won't in general be flat.
Could someone clarify this?
Does this sentence mean:
"The new mesh will consist only of quadrilaterals. Each quadrilateral won't in general be flat."
or
"The new mesh will consist only of quadrilaterals. The mesh won't in general be flat."
isn't the image wrong? A cube shouldn't become a sphere with catmull-clark! âPreceding unsigned comment added by 85.225.115.25 ( talk) 19:15, 30 December 2007 (UTC)
The weights (n-3)/n, 2/n and 1/n are definitely not the ones used in the images. K-3D uses (n-2)/n, 1/n, 1/n. Similarly every other illustration on CC SubD uses this set of weights. Here are two movies showing the different Subdivision stages: (n-3)/n, 2/n and 1/n: http://dl.dropbox.com/u/281539/jReality-CC.mov (n-2)/n, 1/n and 1/n: http://dl.dropbox.com/u/281539/jReality-CC-2.mov
Clearly the method with (n-3)/n causes the weight to vanish for valence 3. Hence the old vertex has no impact whatsoever in the new location. While there are other approaches to handle extraordinary vertices, they usually result in less "round" edges because they give a larger weight to the old location of the vertex during the move stage. â Preceding unsigned comment added by Moritz Angermann ( talk ⢠contribs) 16:17, 8 March 2011 (UTC)
>> and take the average R of all n edge midpoints for edges touching P, where each edge midpoint is the average of its two endpoint vertices
Can someone clarify this? Does this mean the endpoint vertices from the original edge or the new edge? Broodle ( talk) 02:47, 28 April 2008 (UTC)
I propose deleting the section "Software using CatmullâClark subdivision surfaces". It is not especially interesting for an encyclopedia, and it is highly unlikely that this list will ever become all-inclusive. For the moment it is just getting long enough to become a visual distraction to the encyclopedic content surrounding it. -- Berland ( talk) 09:30, 14 August 2008 (UTC)
I find this section rather difficult to understand. A few graphical masks would be of much more help than "face point"/"edge point"/... (btw: are you sure it's correct or do I still not understand it? :) Is an edge point really the average of all neighbouring face points? (I thought the points were only dependent on the original pts?) âPreceding unsigned comment added by 91.19.90.230 ( talk) 13:49, 21 October 2008 (UTC)