Rendering Problem! why the model looks like this.....

[lixinpm]

 

Hi, Everyone,

 

I have one project which need to make 3D model. When I import SU model and plant trees, the model look like very wired. Does anyone know the reasons? But if I copy all the elements to new file, it becomes fine. But after a while, it happens again. The 2D drawing is fine and only rending 3D is wrong.

 

Thanks!

 

Best

 

 

Edited April 21, 2023 by lixinpm

[Jeff Prince]

Are there some items really far away from the origin?  That is usually the culprit.

 

Also, it looks like you have overlapping geometry in some areas, that creates "z fighting" when two or more things occupy the same space.

Edited April 21, 2023 by jeff prince

[lixinpm]

Thank you so much for your suggestions. I copy the all model to the original and it seems to be good. This problem happens Sketchup as well and never thought VW has the same problem. Thanks!

[Jeff Prince]

37 minutes ago, lixinpm said:

Thank you so much for your suggestions. I copy the all model to the original and it seems to be good. This problem happens Sketchup as well and never thought VW has the same problem. Thanks!

 

Many CAD programs have difficulty when things are far from 0,0.  The math and graphics get complicated apparently.

[jpccrodrigues]

6 hours ago, jeff prince said:

 

Many CAD programs have difficulty when things are far from 0,0.  The math and graphics get complicated apparently.

This has any relation with Georeferenced files? Always had this question... 

[Tom W.]

26 minutes ago, jpccrodrigues said:

This has any relation with Georeferenced files?

 

You can move the User Origin wherever you want (the coloured axes) but the Internal Origin (blue crosshairs) needs to remain centred on your geometry so that all geometry remains within 5km like Jeff says. It's to do with floating point numbers + the max degree of accuracy that can be achieved 6 decimal points or something like that... Stray too far from the Internal Origin + the computer can no longer do accurate calcs on it because it can't accurately represent the numbers involved...

[Jeff Prince]

6 hours ago, Tom W. said:

so that all geometry remains within 5km like Jeff says.

You can have geometry much further than 5km from the origin, as long as the geometry is centered on the origin.    Someone from vectorworks needs to explain it why this is, because the math seems like it would be the same.

 

I tried to break Vectorworks with this one and failed…

 

 

[Tom W.]

1 minute ago, jeff prince said:

You can have geometry much further than 5km from the origin, as long as the geometry is centered on the origin.  

 

 

But is this peculiar to site models only? If in that file were you to draw a 55 mile long line across the top of the site model would that not mess things up?

 

[Jeff Prince]

3 hours ago, Tom W. said:

 

 

But is this peculiar to site models only? If in that file were you to draw a 55 mile long line across the top of the site model would that not mess things up?

 

No, it works.  I’ll have to throw a building model out at the edge of the site model and see what happens.

[jpccrodrigues]

On 4/22/2023 at 8:53 AM, Tom W. said:

 

You can move the User Origin wherever you want (the coloured axes) but the Internal Origin (blue crosshairs) needs to remain centred on your geometry so that all geometry remains within 5km like Jeff says. It's to do with floating point numbers + the max degree of accuracy that can be achieved 6 decimal points or something like that... Stray too far from the Internal Origin + the computer can no longer do accurate calcs on it because it can't accurately represent the numbers involved...

 

Having Georeferenced files is precisely that: having drawn elements referred to a certain datum, usually large kilometers away. If you move the internal origin, you compromise the position. A common way to verify that is the geoimage tool. You need to determine the datum, import the file and, if everything is correct, you get an accurate image. But if you change the internal origin of the file... The relative position changes and the image is moved as well. 

 

Considering this, would you keep georeferenced files or keep the drawn elements close to the 0 0 0?

[Tom W.]

10 minutes ago, jpccrodrigues said:

having drawn elements referred to a certain datum, usually large kilometers away.

 

Yes but that datum is the User Origin + this is just a superficial thing - VW doesn't care about it. The Internal Origin is what it uses for its internal calculations. I am using georeferenced files all the time. I have my geometry centred on the Internal Origin but the User Origin is as per the British National Grid so is 658km away... This is all set up in my template files so I am never moving anything, I just import the georeferenced geometry + it lands in the correct place + that's it.

[Ramon PG]

Also, try not using Hidden Line foreground rendering on imported SketchUp.