X4 Ray Tracing - Optimal CPU

[Ian Pellant]

Thanks Tommy,

That's what I was looking for.

Setting the ambient light levels in CA X4 ray tracer is very different to the older versions of Chief that used the POV Ray engine. Ambient of around 50% worked with the old software, the current needs to be boosted up more... however an export to POV drops all the settings and the image is much brighter.

And why use POV Ray? .... the answer is twofold when needing to do a lot of ray tracing:
1. POV Ray can be run on a computer that does not have Chief Architect installed - so the task can be done on any other office computers and run overnight. Offload the work to non-production computers.
2. POV Ray supports batch processing. If you have many ray traces to do, you export them all from Chief then set them up on another computer to run as sequential jobs in a batch queue. Doing this you can set up a lot of ray traces to be done after hours.

If you don't export to POV Ray and have to run the CA built-in ray tracer, then you have to hang around for each one to be finished.... has anyone tried opening several (say 4) different plans in Chief at the same time and tried to ray trace each one at the same time??

If we are stuck with manually starting each plan to ray trace and waiting for it to finish, then doing each in the shortest time is very important (how many and how long are one's coffee breaks?).

I'm confronted with a sales manager who wants all the house designs to have more decorative images for the brochures... there's about 94 existing designs and we need to add about 20 new ones. Modeling each in Chief is the first step (only need to be facade models - that's why the test plan was tossed together just to get a frontal view) then each would need ray tracing. Do the math and that will well and truly tie up a computer (and me) for months. Elapsed time for ray tracing is a very big business concern.

Just experimenting with the ray tracing settings to get the desired results is very time consuming if it takes 20 minutes to get a low res job such as in the test plan. For A4 (US Letter) size brochures the horizontal resolution needs to be about 800 pixels with anti-aliasing turned on the smooth the edges. If I can keep that down to under 2 minutes, then I have a chance of doing the work.

I am trying to determine if the latest AMD FX 8 core processors will ray trace quicker than the Intels. It has been easy to configure hardware (using a Shuttle bare bones) to use an i-7 2600, but the AMD has proven to be a monster... very little support for it in Australia... but still possible.

Cheers.

[redwood]

Was your test plan somewhat similar to those that you will need to ray trace in real life?

If so, you really shouldn't have a problem in getting them done in around a minute. My machine is a stock Dell off the shelf and it did it in 68 sec. Certainly there are a lot of faster units out there.

[Ian Pellant]

Thanks Mark,

An i7 2600 is the Intel web selector recommendation for CAD / Modeling.

RAM over 4GB is possibly superfluous... but it's so cheap that adding more is irrerestable. Some systems will enable dual channel switching if pairs of slots are filled. That may or may not improve ray tracing... dunno. It also means that 4GB x 2 is possibly a faster option than 8GB x 1 for DIMM configuration.

The test plan is a bottom end example... in practice, more detail, some light sources and more landscaping will be used and at higher resolution and probably with more advanced ray tracing options. If the plans are built up for brochure presentations there will be full internal detailing - that may blow the processing time up if internal details will be seen through windows (using window blinds is a way to limit that... maybe).

Thanks for reminding me of Dell.... I haven't explored their web site for a solution, yet.

Still trying to configure an AMD FX 8xx solution for price comparison. Ther are a lot of older AMD motherboards that were built for Athlons and Phenoms, and with a BIOS upgrade can support the FX... yeah, right. The Asrock Fatal1ty 990FX Professional motherboard seems to be the best choice for a roaring AMD FX 8 core system. Keeping motherboard manufacturers up to date is one reason AMD and Intel change the CPU "slot" every couple of years.

Cheers.

[redwood]

Ian, perhaps you should post a plan on the higher end. That should get you a better feel for the power of various processors. I know that there are some users here that are using AMD's with multiple cores.

There have been similar threads here, but your test plan was great and simple. Load it, select the camera, and ray trace.

[Ian Pellant]

Thanks Mark,

I have a slight problem with posting some "real" plans in that they all use custom materials and textures that are a pain to bundle so that Chief finds them all for rendering. It's giving me grief with my X2 plans. I use the X2 export functions and it seems to find and put all the dependent image and pattern data into the folder, but Chief X4 always fails trying to find some of them... and thus negates ray tracing until the images and textures are reset. So: I built a simple plan using only Chief X4 Core library objects to be sure that anyone who loads it should have no problems.

What I will do is load up the ray tracing options, test it, and re-post the plan (without changing the model). That way a simple comparison can be seen between low end ray trace and the top end.

That may take me a while.... the current settings run for 20 minutes on my old box... top end settings may take me hours to get right. Ce La Ray Trace!

Cheers.

[Glenn Woodward]

1min 34sec for me.

[Doug Park]

A couple of comments about X4 ray tracing.

1) You can queue ray traces.

2) You can continue to work in Chief while they run as they run in a separate process.

While this may slow down your work and ray traces it is probably way faster to do them and your work on your high end machine than to farm them out to a low end machine.

In general most of the time when you are drawing plans your CPU will have tons of extra bandwidth. Usually more than 90% of a computers compute power is never utilized so running ray traces in the background while slowing your system slightly will complete almost as quickly while you are using the computer as if you leave it completely alone.

If you are ray tracing and doing work you may wish to select the optimize for Chief option in preferences. This takes one core out of the ray tracing pool to devote to the rest of what you are doing.

[Ian Pellant]

Thanks Doug,

I managed to tie the computer up with an 8 1/2 hour ray trace that was not especially exciting... buzzed away for several hours photon shooting before any view draw occured. Blatantly obvious that the old P4 is useless for production ray tracing... It's chewing away again on another trace at this moment. The "art" in ray tracing is finding the settings that give a good result without putting the processing time through the roof

Still don't have a good clue as to whether an AMD FX 8 core will be quicker than an Intel i7 Quad core. "Common sense" would say: "8 cores are faster than 4". After hours of finding a motherboard and RAM configuration to suit an FX-8150 the system costs are about $10 different between an AMD or Intel configuration - custom builds. Can't find any built systems using the AMD FX-8xxx processor (in Australia most systems off the shelf are "small office" or "home entertainment", then jump to over the top "gamers".).

I will experiment with 4 copies of the test plan and ray trace with the simple configuration (which after a system BIOS tweak I got down to 17:47 (whoopee)). That may strain the old box... which uses a Prescott P4 - one of the last of the "hot" ones running at 3.6GHz - CPU fan buzzing away in overdrive.

Cheers.

[lbuttery]

then jump to over the top "gamers"

Ian:

CA's has recommended gaming PC's for Chief

how much "top" depends on your budget

Lew

[Ian Pellant]

Hi Lew,

Nope... the gamer machines focus on:
Very fast hard / SSD drives
Crossfire or similar multiple gaming video cards

Both of which add considerable cost and are of little benefit to CAD apps and especially not ray tracing. Double the system cost for no performance gains... not a good move.

The disk drive and video card do nothing while ray tracing is running. Ray tracing is mostly CPU intensive.

That said: the motherboard and RAM I'm looking at is top level gamer stuff- but the video card will be FirePro (CAD certified, OpenGL accelerated, not so much DirectX) and the hard drive will be a modest WD Black Caviar, not a Velociraptor. My system configurations are pricing at Aus $1400... gamers seem happy to spend twice that.

But if one has to buy a ready made box, then an average gamer box is better than the average office box. I've been building PCs since the mid 80's so I tend to focus on application specifics.

Cheers.

[lbuttery]

Ian:

Chief is not CAD based

it is based on OpenGL

which is why CA recommends gamer PC's/video cards

however, if you are using other CAD apps then you may
have other requirements to consider

Lew

[Ian Pellant]

Hi Lew,

CAD generically is: Computer Aided Design... it is NOT AutoCAD!

AutoCAD is Computer Aided Drafting.

One could call Chief Architect CAAD - Computer Aided Architectural Drafting.

Revit can be called CAAD and it is totally OpenGL based... as are many advanced "CAD" apps.

I use Revit a lot and it has always been a pain to enter an architects office and find they have gaming type computers... sold by the local "IT guru". Very mediocre.

AutoCAD tends to use DirectX. It's a clunker... and always was... I used to work for Intergraph (spawners of MicroStation) and we all considered AutoCAD to be a toy... I still refuse to have a frontal lobotomy in order to use AutoCAD.

Revit and Chief Architect use OpenGL... which most gaming video cards are NOT especially designed for.

I've used ATI cards since 1988 (VGA Wonder).... Rage was good. Radeon has been a mixed agony and I will never buy another one. The Radeon team seem to aim totally at the gaming market and after 2 years, dump the previous cards into the Legacy bucket. Support drops off rapidly.

ATI FireGL, now called FirePro is a different story because the cards are designed for modeling design professionals and support is maintained almost indefinately.

Take the time to explore the AMD/ATI web site and discover what FirePro is about and the heavy weight design modeling systerms that it is certified for. (The heavy weight solids modeling softwares used for designing motor vehicles, aircraft, ships, space stations, etc.)

Sorry for getting a bit steamed but the number of arguments I have had with computer store guys trying to tell me I don't need certified OpenGL hardware acceleration when all I need is DirectX, are beyond count.

Gaming cards are optimised for bitblitting - filling the screen with images as quickly as possible. CAD requires vector drawing to the screen... One possible reason Chief Architect uses OpenGL is that DirectX support for vector line and text dropped off after DX-7. I was programming with the stuff way back then, when bitblitting took over in DX-8. (I think it was about Chief version 7 when they dropped DirectX and went OpenGL?)

Cheers.

[lbuttery]

Ian:

CA has stated many times that Chief derives no perceivable benefit from the Nvidia Quadro cards which are CAD based
especially in relation to the extra $$$

they recommend mid to high-end gaming cards

CA has never mentioned DirectX - it appears to have no relation with Chief

you may want to discuss directly with CA's sales team

Lew

[Ian Pellant]

Lew,

The topic of this thread is CPU choice for Ray Tracing.

Choices mostly being between AMD FX-8150 or Intel i7 2600 processors.

My need is to ray trace a lot of models in the shortest time possible.

The video card has nothing to do with ray tracing.

Chief Architect X4 uses OpenGL. Revit uses OpenGL.

AutoCAD used DirectX.

Much earlier versions of Chief used DirectX. Then ART moved it all to OpenGL.

Professional 3D modeling softwares generally use OpenGL. Not DirectX.

There are almost no off-the-shelf PC's to be bought that are optimised for OpenGL.

Microsoft pushed DirectX for it's X-Box which was aimed at home entertainment and gaming. Most Windows based games use DirectX. Most gaming PC's are optimised for DirectX.

At the consumer level, if the choice is between an "office / business workstation" with Intel Integrated Graphics or a "Gaming" computer with accelerated graphics then the gaming computer is the better choice.

Have you ever seen a computer on sale that is labelled: "Optimized for Chief Architect" ?

It is a sales dilema outside the context of this thread.

Cheers.

[lbuttery]

Ian:

just responding to your comment about "top gamers" in post #23

I know that raytrace doesn't use video card
but does use cpu and cores - lots of cores

renders use the video card and renders are also important to chief

thus a good/great chief PC would have a good gaming video card and
lots of cores with a fast cpu to cover both renders and rays

8 - 16 GB of cpu ram and 1 - 3 GB of video ram

Lew