[Cosmasad]

Good morning Jeremy, good morning friends in the cyberworld,

We are working toward our deadline and ran our first rendering last night. (8 hours at SL=16). Although the image looks pretty good, there are definitely some problems and we need your assistance with them. We are listing the problems below, but wonder if we could upload the file to your FTP site? If so, which file should we send you – the original .3dm, the Maxwell image or the MXI?
Here is our list:

1) Why is it still grainy – particularly near the top where the ceiling plane is?
2) What would we have to do to get past the grain?
3) The spots in the ceiling that look like sprinkler heads are actually track lights. The tracklights where physically constructed in Rhino to look like tracklights but we attached spotlights to them. You can see their effect on the carpet below, but why don’t we see a hot spot where the light is coming from? What can we do to create that effect?
4) More mysteriously there are several recessed “canlights” in the ceiling above the tracklights that should all be radiating light. We see only one hot spot in the ceiling. You should be able to see at least eight. We went back to our original .3dm and checked all the canlights. They are mesh circles with emitters attached.
5) The resolution was set at 1641 x 1040. Since images display on screen at 72 dpi why does it look grainy when we display the image full screen?
6) The counter at the left of our image should have marble on them. For some reason the Material Editor for it is showing a “bad path”. We are puzzled at how this happened? In the future, how do we check for bad paths before we print? Do we have to use the Material Editor and check each mxm that’s attached to the model?
7) Similarly, the carpet below the furniture had an mxm attached to it for “Red Rough Tile”, but it’s showing a bad path.
Finally, most importantly why is there a big MAXWELL RENDER watermark across the center? I don’t think I am working with a demo version. I downloaded it off the Portal after paying for it.

Your help with these issues would be appreciated.

Thank you.

[JDHill]

If you like, you can upload your file (I would always want .3dm files, never MXS, and never MXI), and I'll take a quick look at it. On your questions:

1/2. If the image is grainy, it means that it needs to render longer, and/or that your scene and/or materials are poorly-designed and are slowing down the progress unnecessarily. In your case, it will be grainier near the ceiling, because the ceiling is not receiving much, if any, direct light. It is a simple matter of probability; the less likely light is to reach a particular region, the longer it will take for a sufficient number of calculations to have been executed for that region. It's not much different than when you take a picture in real life; which parts do you expect to turn out the grainiest?

3. How exactly does one 'attach' a Rhino spotlight to a piece of geometry? In Maxwell, every emissive object must be an actual piece of geometry with an emitter material assigned. In the case of your Rhino spotlights, you are seeing light cast from them because the plugin has generated geometry based on each spotlight's parameters and assigned each one the IES-based emitter material you specified. You are not seeing light from the spotlight geometry itself (i.e. the generated spotlight geometry) because that is how native lights are translated; their geometry is hidden to the camera, in order that they may behave as lights do in Rhino, where no light is seen radiating from any specific geometry. Even if that were not the case, you still would not see light radiating from the spotlight geometry if you use an IES emitter; an IES basically describes a 'volume' of light which radiates from a point specified by the geometry it is attached to. Regarding your actual lights/fixtures, you are not seeing any light emitting from them because, most likely, you have not assigned any emitter material to them.

4. Are the mesh circles pointing in the correct direction? Objects and meshes have a 'normal' direction, and this is the direction in which light will radiate when they have an emitter material assigned. Use Rhino's Dir command to check them; they may be shining up into the can, rather than down. If this is not the case, then I will want to look at the .3dm to determine if there is some unknown bug preventing your emitters from being successfully attached to your emitter geometry.

5. I have no way to tell you the answer to that. What size is your screen? 1641 x 1040? What application are you using to view it? How are you displaying it full-screen? Lastly, what do you mean by grainy? Grainy, as in, not rendered long enough, or grainy, as in pixelated due to being interpolated up to a higher resolution?

6/7. If the material editor tells you there is a bad path, you can click the red hyperlink to be shown a list of all bad paths referenced in the material. That will help you in locating them so that they can be fixed.

8. Your license is not installed correctly, and as a result, Maxwell is running in Demo mode. You should have received license info from the sales dept. when you purchased, so check your emails; they should include instructions for installing your license. Generally I believe the procedure consists of copying some text into a text file, but I do not know for sure if that is the way the system works currently.

[Cosmasad]

Hey Jeremy,

I have uploaded the .3dm and the .png so you can see what we saw. The View that corresponds to our rendering is Named View 1 in the Perspective Viewport. Certain layers that are marked “Keep Off” have to be off so you can look into the model.

Responding to your answers one by one:

1 / 2. “Please elaborate on what would make a scene and/or materials poorly-designed and are slowing down the progress unnecessarily.” I understand the rest of the paragraph but could really use tips on what would make a scene poorly designed.
3.Totally understand this.
4. Totally understand this.
5. My screen is 2560 x 1440 (27” Apple Cinema Display) (by the way I am running Windows 7 on bootcamp on a Macbook Pro with 8mb RAM). I initially used the Windows Photo Viewer to view it but since it won’t let me display full screen, I switched to Quicktime’s Picture Viewer which does have full-screen. How would I describe what I see when I display it full-screen? Looks grainy. That’s the best word. If I can’t get less grain after 8 hours how many hours do I need to run? By the way --dumb question but would the fact that my .3dm is 200 mb play a role here? When I built the file I made the mistake of not using block instances for all my furniture and light fixtures. Now I am rebuilding the file and using blocks to make it smaller. But would a larger file take longer to render?

6 / 7. I clicked on the hyperlink (the red “Yes” warning next to “Has Bad Paths?” and found a list of three invalid paths for this particular mxm. Again, the question we are wondering is how this could have happened, since we inserted the path by clicking on the Folder icon to the right of the path field under the Material Name field in the Material Editor and migrated to where the mxm was kept. Here is what the Bad Paths list said:

Invalid paths report for Material: sd_Branco_Sab_pol
------------------------------------------
MAP @ TEXTURE 'BSDF->Reflectance 0°': C:\Programme\Next Limit\Maxwell\materials database\mxm files\Unsortiert\in Arbeit\Granit_Branco_Sabina\Branco_Sab_poliert-d.jpg
MAP @ TEXTURE 'BSDF->Reflectance 90°': C:\Programme\Next Limit\Maxwell\materials database\mxm files\Unsortiert\in Arbeit\Granit_Branco_Sabina\Branco_Sab_poliert-r.jpg
MAP @ TEXTURE 'BSDF->Bump': C:\Programme\Next Limit\Maxwell\materials database\mxm files\Unsortiert\in Arbeit\Granit_Branco_Sabina\Branco_Sab_poliert-b.jpg

What we are asking for here is advice on what we might have done wrong so we can avoid doing it in the future.

The other confusing thing about this is that bad paths usually cause a rendering to fail right at the beginning before it even begins to “voxelize”—so why did it go all the way through this time even though there were bad paths?

8.Understand that our license is not installed correctly. We will look back at the original email message that preceded our download and see what we may have done wrong. Glad that we caught this.

Thank you.

[JDHill]

1/2. This is much too broad a topic for me to address here on this plugin forum; although I have been helping you with general issues a bit recently, I am the plugin's developer and my primary purpose here is not to be a channel for general purpose Maxwell tech support. To put it in as small a nutshell as I can, firstly, do not ask Maxwell to render things which do not matter. If you draw some geometry twenty miles away from your scene, Maxwell is going to render it, even if you can't see it at all -- Maxwell is an unbiased renderer, so it does not attempt to make guesses about your intentions. Secondly, build materials which mimic materials you might find in the real world. In the real world, you will never find the color [255, 255, 255]; at best when you see something white, you are looking at something more like 220-230. You will also never find a perfectly reflective surface in the real world; so don't ask Maxwell to render one. Just think about a ray of light hitting a surface and bouncing back -- what would the world look like if no energy were lost (converted to other forms, that is) when light bounced around? Well, what's your Maxwell world going to look like if you tell it that such materials exist? Lastly, you can help out the calculation a bit sometimes; think about a light ray trapped in a room -- it will bounce around until all of its energy is lost. As I wrote above, Maxwell takes your scene as you give it, so it's not going to do anything tricky to try to help here, but nothing is stopping you from helping; open up a wall behind the camera if it won't adversely affect the image; by doing so, you can let some of the less interesting light rays escape out into nowhere, and therefore cease to represent a calculation cost.

5. It sounds to me like a combination of the two then: an image which needs to render longer, which is then being stretched quite a bit beyond its native resolution for full-screen display. There is no conclusive answer to the question of how long a render needs to be calculated; it is completely scene-dependent. I could build you one scene which would be finished in two minutes, and I could build you another which would not be complete within the span of your lifetime. Maxwell is not a 'this region is done, move to the next' type of renderer, -- it is rather, as they say, a light simulator, and it will keep on simulating more and more light interactions the longer you let it work. As to the question of scene size (MB), Maxwell hardly cares at all about complexity of geometry; what matters is how difficult it is to calculate light rays, and that depends on the makeup of the scene, and on the materials used.

6. The way that it happens is usually that you download an MXM from the MXM Gallery, and this MXM contains texture paths which were created on a different machine. When you clicked on that folder icon, you were importing the state of that MXM file into the material you were currently editing in the material editor. If bad paths are contained inside of that MXM file, then you will see them being reported there in the material editor once it has been imported.

You can alter your strategy to let the plugin help you out a bit here; if you access the MXM Gallery from the plugin (right-click in the Scene Manager > Materials window), then when your chosen MXM is downloaded, the plugin attempts to fix up any bad paths it contains. After doing so, it saves the MXM to one of two places: (a) if the document has been saved, then the MXM is saved in an 'mxmgallery' folder next to the document, and its textures are saved in a 'textures' folder inside that. If the document has not been saved (and therefore has no location on your disk), then the MXM is saved to an 'mxmgallery' folder in your documents folder; you can also find this folder pre-populated in the drop-down

In practice, there is a choice to be made on the plugin's part: export an MXS with bad texture paths and let Maxwell tell you about it, or disable the textures preemptively. The plugin chooses to do the latter, and as a middle road, provides the 'Bad Paths' report in the material editor, as well as optionally, at export time (see the plugin Option 'Disable Path Check'). Usually this takes care of any issues, but in looking at your scene I did notice that while I am doing this for textures, I am not doing it for emitter MXI/HDRIs and IES files. So Maxwell can still refuse to render. I'll tweak this for the next plugin build, but until then, you'll have to make sure the paths you use are valid.