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Building a townscape for the new. Happy Families, project I'm hoping to set up the lighting this evening.

In 3ds max ( many moons ago ) there was a "sun" seting so you could specify where the location was and what time of day, then the software would produce a sun effect for those settings.

Working in V17, is there an equivalent in AM or, is there a global illumination setting. If so, could somebody kindly point me in the direction of the info on how to set it up and use it?

What I'm after is a single light source, giving a, very rough, approximation of daylight.

Rather than have to introduce lots of lights.

 

simon

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  • Hash Fellow
What I'm after is a single light source, giving a, very rough, approximation of daylight.

 

 

 

What you want is one Sun light for the single light source. The additional light of the surrounding blue sky (if that is desired) is done with Global Ambience and AO.

 

 

In 3ds max ( many moons ago ) there was a "sun" seting so you could specify where the location was and what time of day, then the software would produce a sun effect for those settings.

 

 

If the exact angle of the sun is important, we don't have a specific wizard for that but it is easy to do...

 

1) Delete or set Active OFF on all lights except one Sun light (called "Key" in default chors)

 

3) Google your coordinates. "London, England coordinates" gets me 51.5072° N, 0.1275° W. You can round those off to the nearest degree.

 

2) Go to Sun or Moon Altitude/Azimuth Table. Plug in your location and it will create a table like this

Astronomical Applications Dept.                                               U.S. Naval Observatory                                                        Washington, DC 20392-5420                                                    LONDON                                                                           o  ,    o  ,                                                                  0 00, N52 00                                                              Altitude and Azimuth of the Sun                                               Feb 5, 2016                                                                  Universal Time                                                                         Altitude    Azimuth                                                                       (E of N)                                                h  m         o           o                                                                                                                                                                                                               07:00       -5.7       108.908:00        2.9       120.609:00       10.1       133.010:00       16.1       146.511:00       20.2       161.112:00       22.0       176.413:00       21.3       191.9 14:00       18.3       206.9 15:00       13.2       220.9 16:00        6.4       233.8 17:00       -1.6       245.8 18:00      -10.4       257.4 

4) We are going to presume that in A:M, when you are looking at the Chor from the overhead view, that North is at the top of the screen and East is to the right. This is normal map convention.

 

5) In the Chor, in the properties for the Sun light, set Transform>Rotate to 0, 0, 0 and set Options>Cast Shadows to ON

 

6) Choose a time from the table. Lets say 3PM or 15:00...

 

"Altitude" is the sun's angle above the horizon... 21°

"Azimuth" is the Sun's angle from straight North... 221°

 

7) The table presents angles from the observer's point of view while A:M needs angles from the Sun light's point of view, but we can still make them work.

 

Enter the Azimuth, 221°, into the Sun light's Transform,Rotate> Y value as a negative number... -221°. (A:M will display that as 139°, which is the same as -221°)

 

Enter the Altitude as is into the Transform>Rotate>X value... 21°

 

Always do the two values in that order, and always zero them out to 0, 0, 0 before you change them.

 

8) the placement of the Sun light in the chor doesn't matter. It creates an infinitely wide set of parallel light rays from an infinitely distant source, like the distant Sun.

 

 

9) Set the Sun light's Intensity and Shadow darkness to taste. Color will vary from slightly yellow, almost white at Noon, to a reddish orange at Sunset.

 

Leave "rays" at 1 and A:M will imitate a slight fill at the far ends of the shadows. Rays greater than 1will create a penumbra effect on the shadows based on the Sun light's "width" setting"

 

This will be a "rough approximation of daylight" without Global Ambience and AO, but if you need those, ask and we can go into that also.

 

 

 

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With apologies for the delay. Had to rebuild the model, twice.

Once because I got carried away with deleting groups, the other because I was starting to get very fussy.

It was testing the computer a lot to as its 45.2Mb in size and there were 9 instances in the cho. Coming in at approx 324 houses, thats about 3x the size of the village I live in !

 

Anyway, enough waffle.

I'm going to try Robert's suggestions re the sun location but, I have no experience with Global illumination and AO. Can somebody kindly point me in the direction of somewhere o learn about it ?

regards

simon

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... ...but, I have no experience with Global illumination and AO. Can somebody kindly point me in the direction of somewhere o learn about it ?

 

 

Briefly... in the properties of the Chor...

 

-turn Global Ambiance Type to "Global Color"

 

-Choose a Ambience color. Anywhere from slightly blue for Noon to reddish orange for sunset

 

-Ambiance Intensity is something you have to balance against the Sun light Intensity in your chor.

 

For noon day sun try 25% Ambiance intensity and 75% Sun Light intensity. It's OK to have the two add to more than 100% but if both are 100% you will get over blown whites.

 

For times near sunrise/sunset the proportion of Ambiance to direct light would be greater.

 

-Set Ambiance Occlusion to 100%

 

 

When you go to render set Render To File Settings>Ambiance Occlusion to ON and...

 

Occlusion Sampling to the lowest number that gets you acceptable shadow quality. Start with 10%.

 

Leave Transparent AO OFF unless you need transparent surfaces in your scene.

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Robert

Thank you once again.

I'm hoping to do a test on the whole town set up but it may have to go through overnight as it is taking up to 20 mins to do basic things like delete cps, or copy and paste operations, even saving.I think it must be to do with the file size. ( 40mb ). Was about to do the test this morning when I realised I'd left a lot of internal patches in place, so it then took several hours to correct that. One I get it sorted out I'll set up a test and try to post the result tomorrow.

regards

simon

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I like the look of that.

I see that Robert already mentioned this but I'll guess that you don't have shadows turned on as there doesn't appear to be any.

 

some renders were set to 720, the others to VGA, so had to redo them..

 

This is where having an external program/utility like Fusion can come in handy as various render sizes/resolutions can be combined.

In that way you don't have to rerender frames which consumes our lives... er... a lot of our time.

Rendering is time consuming but necessary. However, in some states and municipalities re-rendering may be considered a crime. ;)

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The shadows can definitely be seen there.

I rarely think shadows are too light (usually I think they are too dark) but that may be the case here as they can barely be seen.

As these are shadows created by the sun and not some other light I'd think there would be more of a contrast.

If on the other hand there are lots of clouds in the sky to diffuse that light... then disregard.

 

In this lastest image the angle of the shadow suggests the sun is at a high position (closer to noon than morning or evening) and yet the darkness of the shadows suggests more of a twilight.

Pending further clarification, I will assume that screen left is west which suggests the sun is going down rather than rising in the sky.

 

As I said, if other effects such as clouds, fog, rain, etc. will be added then things are looking fine.

I can't help but wonder if you've colored the side walls of houses/garages a darker color because those areas don't seem to match with the shadows... in fact their darkness appears to be about right.

 

If in the evening (or early morning) the sun will be shining it's light at a steep angle which will produce longer shadows.

 

Here's what I tend to do with lighting:

1. Remove all of the default lights

(as everything should render black now I know what I'm working with in the scene - and I can see what surfaces are emitting their own (ambient) light.

2. Add one sun light and angle (rotate) it appropriately for the effect (or timing of day) the scene calls for.

3. Add additional lights as necessary - usually this is driven by 'real' light locations such as lamps, car lights, etc. Start with primary lights and move on to other 'missing' lights (lighting of windows, etc. at night)

4. Add additional lights/color to bring out subtle detail in areas with too little light.

(5) An optional step is to dampen down a too brightly lit scene with negative lights. It's best to turn off shadows with negative lights as those will render in reverse...i.e. badly)

 

Your mileage may vary but it can be useful to think of lights as characters in their own right.

What is their purpose in the scene? With respect to the story, how are they directing/enlightening us?

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  • Hash Fellow

Something is set wrong. There should not be that much light inside the garage.

 

Can you show a screen cap of all the properties of the light ?

 

 

Another suggestion... make the roof overhang the triangle sides of the house. You want the shadow that will cast.

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  • Hash Fellow

OK, I see...

 

On the Sun light set "Width" to 0 and "Darkness" to 100

 

This will make the light and its shadows more Sun-like.

 

After you do that you may want to re-balance your light and global ambiance intensities.

 

 

 

 

Setting darkness to less than 100 is something typically done when AO/Global Ambiance is not being used. It simulates ambient light by lightening shadows but when you use it with AO/Global Ambiance it makes the shadows so light you can't see them. It also create unnatural illumination in enclosed spaces like the garages.

 

Setting the Width greater than 0 causes a different AO/Global Ambiance approximation where a shadows get lighter the farther they are from the object that casts them. The greater the Width, the faster they fade. If they fade too soon they may never reach the object the shadow is supposed to be seen on.

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Apologies for the large file size, couldn't convert it without losing the quality that would enable critical feedbak.

This was the overnight test.

Go set to 50% Sun set to 50% intensity shadowsset to 75% on the sun light.

I found the shadows too dark on 100%

 

Following Roberts observatiuons re the house design, I realised they were too tied to the original idea of the 'house of cards' so, intend to spend the rest of the day redoing the house ( again ! ).

The 'small pegs' below the hedge were supposed to be the trunks the hedge body was supported by but, they will go inthe new version too...

simon

 

Estate 04.mov

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