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View Full Version : Problem with light and shadows on V4D 9.52


raska
02-28-2006, 09:47 PM
After to make a new project I've observed that a strange shadow appears using the sun light, (Infinite and Raytraced Hard Shadow).
I've saved the project, loaded it in old Cinema v.8.5 and there is no one problem in that version.
I've made an image so you can see more accurately what I am talking about.

Here you can take a look at the image.

http://img154.imageshack.us/img154/7664/kite892op.jpg


I think it is a bug on new version 9.52 because I don't made any change in the project, only save it and load it from one version to another.

I'am on a MAC G5 dual - OSX 10.4.4 - tiger.
Tested the same project on a friend's PC AMD Athlon and no one problem there.

Thanks.

seco7
03-03-2006, 04:48 PM
I haven't had any problems like you have described, but I cannot really tell by the pictures what is happening. What is casting the shadow? The 9.52 version actually looks correct to me? Are you using any Alpha maps or compositing? I occasionally have has some problems with clips.

Per-Anders
03-03-2006, 09:37 PM
i beleieve that the sun now uses an area shadow in 9.52, how large is your model? if it's very small in units then it may be a precision problem. scale up your model and see what happens. remember that cinema's units are not real world units as such, and you want your smallest detailed objects to be at least 1 unit in size.

nycL45
03-04-2006, 12:09 AM
....remember that cinema's units are not real world units as such, and you want your smallest detailed objects to be at least 1 unit in size.

Whether I am in metric or imperial units, a conversion factor is necessary to determine how much to scale up the smallest object to 1 C4D unit. What is the conversion factor?

AdamT
03-04-2006, 01:06 AM
Whether I am in metric or imperial units, a conversion factor is necessary to determine how much to scale up the smallest object to 1 C4D unit. What is the conversion factor?

Locate the smallest object in your scene, determine it's smallest Cinema unit, and divide one by that number. There's your conversion factor. The unit measures that Cinema uses (feet, meters, etc.) are irrelevant. As far is Cinema is concerned, one kilometer = one millimeter.

nycL45
03-04-2006, 02:50 AM
Locate the smallest object in your scene, determine it's smallest Cinema unit, and divide one by that number. There's your conversion factor. The unit measures that Cinema uses (feet, meters, etc.) are irrelevant. As far is Cinema is concerned, one kilometer = one millimeter.

Okay. Then I should be able to take the 1/x = c-factor and enter that figure in the Scale Factor and everything imported from CAD will be scaled to C4D units and in their correct 3D positions. True?

Then the Coordinate Manager>Size and the Object Properties>Size would now give the new size which would not be the correct size. Example, smallest item = 3/4"; 1/.75" = 1.33 = c-factor; 1.33 x 6 = 7.98; and And each time I wanted to create an object in the C4D file, the size would have to be adjusted with the conversion factor. And this applies to the object's location, too. True?

If the response is true then, one would wonder if all the work is going to be worth it.

raska
03-04-2006, 10:43 PM
Well, peranders.

You are almost right, re-scaling the model to a bigger scale make the shadows still more visibles and ugly, but re-scaling to 10 times lower, they almost dissapear. The original model is made with the standard rectangle and cube measures when you open them.

After to do a ton of tests, I decided to create a new project with only the sticks that are projecting bad shadows and just the sun. Well, no bad shadows on this way. So I re-edited the project and I appreciated that there are some sticks duplicated in the same place after to make the first cube duplicated 4 times around the 0,0,0 axis. They are the culprit of the strange shadow effect.
I deleted all duplicate sticks and done. No more shadows.

Now I only ask myself why those shadows are not present on version 8.503 :D

Thanks to all for your fast answers.

AdamT
03-04-2006, 11:25 PM
If the response is true then, one would wonder if all the work is going to be worth it.
That's true. If it's a case where you're going to be continually importing and modifying in a 3d party app you'd want to round to the nearest whole unit. So for example, if you have a smallest part that's .035 Cinema units, scale the scene by a factor of 100 so it's 3.5 Cinema units.

Something to consider, though, is that you also want to avoid having scenes that are much much *bigger* than the default grid--because you run into floating point errors that way too. Sometimes you just have to compromise. Instead of modeling a whole city block down to the level of an individual screw in a light switch cover, break the scene up into macro and micro scenes. Or, use textures in place of very small details. Or ... sometimes you're just screwed. :)

nycL45
03-05-2006, 01:19 AM
That's true. | Sometimes you just have to compromise. | Or ... sometimes you're just screwed. :)

Yep, that says it all. lol :thumbsup:
BTW, I will try upscaling/scaling up to test the process. Thanks.

Ernest Burden
03-05-2006, 05:02 PM
Is there a phong tag on those stick surfaces? The bad shadows look like an effort to smooth, or round, the surface.

raska
03-06-2006, 04:47 AM
No Ernest. there is not any phong tag on those sticks, there is a double stick instead. Just 2 equals sticks in the same position. That's the reason of the bad shadows there. Thanks for your suggest, but all is solved now :D

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