'Old_2013/tutorirls & Tips'에 해당되는 글 29건

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  1. 2008.06.30 Contours shaders
  2. 2008.06.30 Clouds with mental ray sky
  3. 2008.06.21 Hell Yeah! - Making of
  4. 2008.06.21 Mental Ray 3.5 - Sky and Sun.
Old_2013/tutorirls & Tips2008. 6. 30. 10:38

By pfbreton

Note:

The detection of contours needs to be based on some sort of threshold value. That threshold is typically ruled by the Angle Step Threshold parameter of the Contour Contrast Function Levels shader (see the description here). Detection of materials or shadows is also performed by that shader.

Simple

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The Simple contour shader will draw all lines to the same width.

Curvature

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The Curvature contour shader will trace a line where the angle between normals falls under a certain threshold.

Depth Fade

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The Depth Fade contour shader will allow you to change the width and color of a line based on Zdepth.

The Zdepth is in world units.

Tip:

Use a Tape Helper Object to determine the Z depth of your view.

Layer Thinner

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The Layer Thinner will let you reduce or enlarge the contour lines based on the trace depth (which is ruled by the Contour Contrast Function Levels shader)

In this example, the glass pane is semi-transparent. The shader detects that situation and makes the lines thinner when they are drawn inside the glass pane.

Factor Color

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The Factor Color uses the color of the material, as rendered by mental ray (as opposed to the diffuse color).

In this example, the materials are all self-illuminating, to ensure a constant color. The shader does the rest.

Width From Light

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The Width from Light will generate contours thick or thin based on the direction of a light you can specifiy in your scene.

Width From Light Dir

avi showing animated light dir here

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The Width from Light Dir will modify the thickness of contours based on the direction of a "virtual light vector" that is defined in the shader.


Width From Color

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The Width from Color will modify the thickness of contours based on the brightness of the color of you materials

Note: The color used by the shader is not the diffuse color of the material, but instead the rendered color, so lighting has an influence here.

Although the name of the shader uses the word "Color", it would be probably more appropriate to call this shader "Width from Brightness", since only the brightness of a color is taken in consideration.

Min Width: width from bright colors

Max Width: width from dark colors

Combi

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The Combi contour shader is a combination of theDepth Fade, Layer Thinner, and Width from Light shaders.

Tip:

Use a Tape Helper Object to determine the Z depth of your view.

Note:

In this illustration, we can see a blue line crossing the glass pane held by the character. This blue line is the reflection of the edge of the floor, behind the camera.

The line is blue (Near Color), because the distance considered is not the distance of the eye ray bouncing in the glass. It is instead the distance between the camera and the edge itself.

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Old_2013/tutorirls & Tips2008. 6. 30. 10:33

by zap's mental ray tips

I keep getting requests from people saying things like "I saw you at SigGraph showing of the mental ray sky and it had clouds in it. How did you do that?".



To which I twirl my moustache and say, 'tis a deep secret....

....just kidding.

Here's the thing. The mia_physicalsky shader uses a 'haze' value to derive a sky color based on the sun position/angle. So a 'hazier' sky is more white/yellowish and a less 'hazy' sky is deeper blue. Okay fine, weather control, you say, but that's not clouds, is it?

Well... actually... it is... if you modulate the haze value across the sky!

Observe this video that I made... it's basically a collection of all test animations done during the development of the sun&sky. Some are bad, some are worse, some are nice, some has bugs in them, some use very low anti aliasing, and none is a peice of art. However they do demonstrate the cloud feature...

What I did was use this texture map (which is a slightly modified version of one I found from some old CD-ROM with public domain sky textures) as a spherical environment map plugged into the haze parameter of mia_physicalsky. That's basically it!

In Maya or XSI you can do this directly, in Max you need to drag&drop your "mr Physical Sky" from your environment dialog into the material editor, uncheck the "Inherit from Sky" and apply the map there.

What is important - though - is this; This is a normal run-of-the-mill LDRI .jpg image, which means it causes a "variation" in the range 0.0-1.0 ... this is way too little for being visible as "clouds" in the sky (the haze has a range of 0 to 15)

So to see results, you need to multiply the level of the texture. How you do this differs between the applications (in Maya you can use the Gain, in Max you use the Output rollout and turn up the RGB Level, etc etc) but setting it somewhere between 5 and 10 tends to look nifty.

Note that this is not a "physically correct" effect in any way, notably because it doesn't actually scatter light, or block light, or create any shadows, or anything like that. But it does simulate "light" cloud coverage very nicely (like high altitude cirrus clouds), and the cool thing is that the clouds coloring automagically follows the sun angle, making very nice sunsets possible....

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Old_2013/tutorirls & Tips2008. 6. 21. 21:52
Hell Yeah! - Making of

Hell, Yeah!, -, Making, of

Vaclav Krivanek, 2008-05-26
Evermotion (http://evermotion.org)


INTRODUCTION
Hello, I want to share with you the small making of my Hell Yeah! portrait of the devil.
First I’ve start with simple base mesh in 3dsmax then I moved my model into ZBrush where fun starts.

Tip: Before you’ll export anything to zbrush, don’t forget to reset xform
(especially when you’re mirroring some objects) you’ll avoid many problems.

MODELING
When I put base mesh in zbrush at that time I actually didn‘t know how the final version will look,
so I start playing with shapes, don‘t be afraid to do crazy things like move ears far from head,
make big nose or so, you can find some interesting shape and then start adding details in your model.
First idea when I start sketching was to make some vampirish head but at the end I get to devil head :-)




































When you’re sculpting, don’t try to subdivide it at 4th level right after you put it in zbrush,
always try to get maximum details even in basic model, when you’ll be quite happy with that,
then just move to another level and add more fine details.

I am mostly using just standard brushes like inflate, standard, smooth, pinch and move.
I actually didn‘t use any special alphas for this sculpture. Great feature is to use lazy mouse (L) for
wrinkles and smooth lines and transpose to move, scale and rotate your object if it’s needed.





















Ok now I’ve finish my sculpture so I need to put it back to max and start the texturing,
you can use erotology if its needed, but I was ok with second subdivision level and
I knew that I won’t use it in some animations so I delete the first one and export the second one to max.
Then I’ve done some unwrap, great tool for unwrap characters and organic things is unfold3d,
UVLayout or other similar programs focused just on unwrapping, it’s much easier and faster
than to do it in max.

When I get my head unwrapped, I’ve import it back to zbrush as a first level of the model

Tip: Do not change anything on the model when you’re doing unwraping,
if you do any change even one edge you won’t be able to import it back to zbrush at a first level of
your sculpture.Then I generate displace, normal and cavity map

MODELING - CONTINUE
Then I start working with the model in max, just setup some basic lighting and composition to more
define the final scene, I also use some basic rig to play with pose but now I am mostly using
transpose in Zbrush to pose my characters. Here is some final setup of lights, pose and camera.











































Then I start with some texturing in Photoshop. I played a lot with layer blending,
just take some concrete photo and blend it nicely to the texture or so, face area
is made from many pictures of people and repainted and blended together.
Sometimes is good to take one channel from normal map and multiply it into texture,
like this you can increase some fine nice detail. I didn’t actually play a lot with
parts which won’t be visible in the final render.

Here is the final diffuse texture:
















I’ve also used some SSS, some specular and reflection masks.

I am using Brazil v2 render system and at that time I had some beta version where included
displacement won’t working well, but brazil can handle many polygons so I’ve used Normal
displace modifier in max where I put my displace from Zbrush, then just put some turbosmooth on
level 3 to get almost same result as some MTD.

I’ve used just 3 lights and very small amount of GI, one main from left with shadows casting and two
others not so intensive to see some contours on the head without shadows.



MODELING - CONTINUE
Ok now I start to play with shaders. For skin shader I used normal Brazil skin shader,
you should always try to tweak shader on some simple ball and do not waste your render
time on your final model. When you’re happy with some result on the ball you can put that on
final model and do your final touches on it.

Here is one of many render tests.













































Ok now is time to do some flames, I used Fume FX plug-in for max,
it’s really easy to use and you get amazing results. I`ve select the horns as a source of flames.
Here is some setup in fume FX dialog for horns

























Then I just click render and let it counting for a while, at the end I go through all the frames and pick
 the one most interesting for me.
I also made few smoke renders to put on his body.

Here is the final render with flames and some smoke.


MODELING - CONTINUE
Then I render few more smoke to put in front of his body to combine them in the final picture.
As last thing I render some fur on the body with default settings just tweak the size and length
of them to get some nice fine fur details in hi-res render. I should use mask for the places
where I didn’t want to grow fur but I was in big rush at the end so I just overlay it and erase
parts where I don’t required.


















































In final compositing in Photoshop, I made a few color correction, paint some hairs on head,
add those smoke renders, add even more blood on some places, tweak contrast and add
simple background. And here is the final result as you know it.

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Old_2013/tutorirls & Tips2008. 6. 21. 21:38

Mental Ray 3.5 - Sky and Sun.
MF, 2007-01-31
by Evermotion (http://evermotion.org)

1. Scene을 Download 해서 설치 하십시오 - start.max
(this model is free for not commercial use). SCENES



2. Scene에 카메라를 설치 합니다.



3. Daylight를 만듭니다. systems -> daylight



4. Daylight를 manual로 설정라고. daylight의 위치를 바꿉니다.

 


5. Sunlight듣 mr Sun으로, skylight를 mr Sky으로 바꿉니다.

 


6. F10을 누르고 Common에서 renderer를 Mental ray로 설정 합니다.

 


7. Material editor로 이동해서 materials을 Arch & Design (mi) type으로 설정합니다.



8. Rendering options (F10)이동해서 FG 등을 설정을 합니다.



9. Rendering을 합니다. -> Environment > Preview:



10. Exposure settings을 바꿉니다.:



11. Rendering을 하면 이미지와 같이Hhorizon값을 낮춥니다.



12. Daylight options에서 horizon to -0,2 변경합니다.



13. 다시 Rendering 합니다.


추가적으로 또다른 세팅으로 Rendering을 해보았습니다.


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