Increasing Resolution of Circles

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Increasing Resolution of Circles August 1/24/09 1:29 AM
Hi Po,

> Po Ku wrote :
> Hi,
> I'd appreciate it very much if you can help me with a
> problem with sketchup pro.  When I draw circles, doesn't
> matter at what scale, they appear to be polygons.
> The resolution is very poor. I haven't tried printing
> them but I suspect they will look the same on paper.
> I couldn't find a tool or window to increase the
> resolution of the drawing.
> Before I decide to buy the software, I'd like to make
> sure I can draw in higher resolution.
> Can you help?
> Po

I see that you sent this about 10 hours ago.  You might have gotten a faster response by posting to the SketchUp Help Group.  I am copying the group with my answer to help other people too.

Your problem is not about Pro or Free.  It is the same for both versions.

Many people think that problems they have with the Free version may be solved by purchasing the Pro version.  For most such problems, this is not so.  The Pro version still has some very useful features if you are using it professionally.

The Free version will do *Everything* the Pro version will except in three areas:
- Export format.  Pro will export in a variety of formats.  Free only exports in one format so you have to use external conversion programs to get other formats.  There are free converters available.
- Dynamic Components.  Only Pro will let you create dynamic components such as a fence that will add boards when you scale its length instead of making each board wider.  In Free you would have to write a Ruby program to accomplish the same results.
- Location.  Pro and Mac Free will let you define the geographic location of your models.  The Windows Free version has a default location that you cannot change except by a tricky method using Google Earth.  There is a free Ruby Plug-in that will fix this for you.  Download it at http://tinyurl.com/awomxw

Po, as you have discovered, in SketchUp, circles are actually polygons.  In the same way, Arcs are sections of polygons.

There is no "resolution" setting in SketchUp.  SketchUp can display and print its 24-sided circle-polygons very sharply.

Using polygons for circles was a decision by the designers of SketchUp that does have some advantages.  With OpenGL 3D display, it is possible to draw "true" circles but these have a disadvantage -- they cannot be filled in.  They are a special case of Lines, which also cannot be filled.  (Or maybe lines are a special case of circles, circles with infinite radius.)  "True" circles must be converted to polygons before they can be filled.

The designers decided that having circles automatically filled and not using the "true" circles would be more intuitive for SketchUp users and would allow users to pay less attention to the internal representation of their models.  (That is my guess.)

There are three ways to get more segments in a circle-polygon:

- The "Before You Draw" method: Immediately after you first select the circle tool, before you start drawing with it, look at the number field in the lower right of the SketchUp window.  This "Value Control Box" (VCB) will be titled "Segments" and will show "24".  Just type a new number of segments (don't click in the box, just type after you click on the Circle tool) and press Enter.  The number you enter will become the new default for the Circle tool.

- The "s-units" method: After you draw your circle, the VCB will display the Radius.  Type a number (again, don't click in the box, just type) and follow it with "s" for Segements (e.g., type 6s for a six-sided "circle" or "48s" for 48 sides).  The number you enter will become the new default for the Circle tool.

- The "Entity Info" method: After you draw your circle but before you make any changes to it (e.g. drawing a line which crosses it and therefor adds intersections to the circle, or drawing the circle in a way in which it crosses other lines that will form intersections), right-click on the circle and select the Entity Info.  If your right-click selects the entire circle, no changes have happened so you can proceed.  In the Entity Info window is a field for the number of Segments.  You can change the number here.  In this case you must click in the Segments field to change the existing value to your new, desired value.

Sometimes, when using the "Before You Draw" method, I have had the new number not get accepted properly and I have had to use the "s-units" method after I have started the circle.

The maximum number of segments in the first two methods is 1000.  If you type a larger number, you will get 1000 segments with no error message.

The maximum number for the "Entity Info" method is 9999.  If you type a larger number you will get an error message telling you that the maximum number is 999.  This error message is in error, you can go up to 9999.

Whenever you use a large number, manipulating that many polygon edges will slow SketchUp down significantly.  Simply deleting a 9999-sided circle-polygon with nothing else in the drawing can take several seconds, long enough to make you wonder if SketchUp is still working.  In fact, it is working *very* hard.

In general, use the minimum number of segments that will produce an acceptable appearance.  Only use large numbers for constructions where you want extreme accuracy and when you will quickly delete all of the hundreds of extra segments.

Po, I hope this helps you in using the software and in your decision whether or not to buy the Pro version.

Yours,
August

P.S. Po, you wrote to my personal email instead of posting on the group.

On the group, it is my choice whether to even read your posting.  In my mailbox, it is a more direct request for my services.  For over 25 years I have made my living by explaining how software works, and right now I have no job.  This took me over two hours to test and write.  That was my free choice.

However, if my mini-tutorial here has helped you, please consider "buying me a beer" by using PayPal.com to send a donation to the same email address that you sent your request to.  Credit cards accepted.  And anyone else who finds this level of detail useful, as a group member you can get my email from my profile.  Anyone who donates will get an equivalent discount on the SketchUp book that I am planning to write.  The more donations, the sooner the book will get done, so please vote with your $.  In addition to tool details that are not in the manual, like the above, the book will also include a LOT on how to use Ruby in SketchUp.

Thanks,
August


     

Re: Increasing Resolution of Circles Gaieus 1/24/09 9:42 AM
> - Location.  Pro and Mac Free will let you define the geographic location of your models.  The Windows Free version has a default location that you cannot change except by a tricky method using Google Earth.

Hi August,

Location was added to the free version of SU 7 in Windows as well. It
even has the Location button at the bottom right.

Gai...

On Jan 24, 10:29 am, August <asm...@yahoo.com> wrote:
> Hi Po,
>
> > Po Ku wrote :
> > Hi,
> > I'd appreciate it very much if you can help me with a
> > problem with sketchup pro.  When I draw circles, doesn't
> > matter at what scale, they appear to be polygons.
> > The resolution is very poor. I haven't tried printing
> > them but I suspect they will look the same on paper.
> > I couldn't find a tool or window to increase the
> > resolution of the drawing.
> > Before I decide to buy the software, I'd like to make
> > sure I can draw in higher resolution.
> > Can you help?
> > Po
>
> I see that you sent this about 10 hours ago.  You might have gotten a faster response by posting to the SketchUp Help Group.  I am copying the group with my answer to help other people too.
>
> Your problem is not about Pro or Free.  It is the same for both versions.
>
> Many people think that problems they have with the Free version may be solved by purchasing the Pro version.  For most such problems, this is not so.  The Pro version still has some very useful features if you are using it professionally.
>
> The Free version will do *Everything* the Pro version will except in three areas:
> - Export format.  Pro will export in a variety of formats.  Free only exports in one format so you have to use external conversion programs to get other formats.  There are free converters available.
> - Dynamic Components.  Only Pro will let you create dynamic components such as a fence that will add boards when you scale its length instead of making each board wider.  In Free you would have to write a Ruby program to accomplish the same results.
> - Location.  Pro and Mac Free will let you define the geographic location of your models.  The Windows Free version has a default location that you cannot change except by a tricky method using Google Earth.  There is a free Ruby Plug-in that will fix this for you.  Download it athttp://tinyurl.com/awomxw