Wednesday, February 27, 2013

Skydome rotation

Here's how to constrain the skydome rotation to the camera:
  1. Create a group for the skydome (skydome_GRP)
  2. Parent constrain skydome_GRP to the layout camera (driver: camera, driven: skydome_GRP), maintaining offset and ONLY constraining translation values
  3. Open the expression editor and create a new expression (skyRot)
  4. Enter these expressions (<skydome> is the name of the sky GEOMETRY, not group and <camera> is the full name of the layout camera):
int $ct = `currentTime -q`;
float $rx = `getAttr -time $ct <camera>.rotateX` - `getAttr -time 1 <camera>.rotateX`;
float $ry = `getAttr -time $ct <camera>.rotateY` - `getAttr -time 1 <camera>.rotateY`;
float $rz = `getAttr -time $ct <camera>.rotateZ` - `getAttr -time 1 <camera>.rotateZ`;
float $deg = 0.8;
<skydome>.rotateX = $deg * $rx;
<skydome>.rotateY = $deg * $ry;
<skydome>.rotateZ = $deg * $rz;
Hit create expression and you're done!

Saturday, February 2, 2013

Simple Fog

Hey guys, there is a really quick and easy way to get atmospheric effects in your shots by following this tutorial.

http://renderman.pixar.com/view/fog-and-atmospheric-effects#Files

The only problem is that it doesn't really work with transparency in cards very well.  I'm still working on a solution, but if you think your scene could use this we'll figure it out.  I'll keep you posted.

Brian

Friday, December 14, 2012

Lighting Shot Assignments

Shot Lighter Length (frms)
14 Kelly 65
15 RJ 39
16 Siran 156
17 Siran 71
18 Jared 71
19 Jared 43
20 Brian 35
22 RJ 65
24 Siran 90
25 Kelly 250
26 Brian 90
27 Kelly 80
28 RJ 37
30 Brian 60
31 (32) Brian 67
32 (33) Siran 75
33 (34) Jared 27
35 Kelly 300
36 RJ 370

31 (32)
actual shot number (shot number in vimeo video)

Monday, December 3, 2012

CompTips_Mask&Zdepth

1. how to get a mask for gus/ ground/ or whatever object u wanna mask out:

<1>.save your lighting file as a other one.
for example: i wanna a mask for gus in shot9, so i saved out my lighting file as other file called 'shot9_mask'.
<2>.create slim shaders with diffuse color of white or black. have the object u wanna mask out attached with color different than other objects.
Remove all the lights u already have, and create a new RendermanEnvLight with color: white;  intensity: 1.0; sample: 512, max v: 2.0.
for example: in shot 9 I wanna mask out gus. so I give him a black color, other set to white color in shader. and then this is my render:
IMPORTANT tips for the B&W slim surface u used in this file:
(1).u need to have the correct displacement attachment to the object. Other wise the mask u render out won't match the outline of your object in the beauty pass. I have already make the some of the surface shader on gus so u guys don't need to remake it. it's in assets/lights/12.0_lights/12.0_lights.proj/slim/palettes/shot12SnowAndBg.splt.
you can find those shaders by open your slim, and File/Open Palette. then open the file above, u will see some black surface shaders for different parts of gus in that palette.
Ask me if u dont know which one is supposed to be attached to which object (u guys have my number right~? lol)

(2) about the snow ground. first make sure u have the effect on it. second, when u make white surface shader for it. make sure change the ' object size' of ur slim shade to 200. otherwise it won't get the correct displacement.


<3>After u have the mask, then u can put gus and env in different render layer, which will also help speed up the render. and Then comp them together. like this:





<4>.If u need to create Zdepth pass for comp atmosphere effect of DOF. I have a way to cheat it.
save your mask file as another one call. 'XXX_Zdepth.ma' (Opppps, so many files >_<)
and then:
(1). connect all the diffuse color of all you surface shader to this mixcolor node: assets/lights/09.0_lights/mixColor_forZdepth.slim (the folder is really messy right now, sorry about that...). and in the SL_box, u can the value of float d to control how far it face into black.
(2). give your sky plane a black shader.
(3). in your renderman control, create a output pass called : 'DiffuseColor'. set it to TIFF. (that's the frame u want for your Zdepth render)

here is an example for shot9's Zdepth pass (I only render the Depth pass for my Env, cuz gus will be in focus all the time)



<5>.Final Comp with another fog layer in front of everything, together with LightWrap & EdgeBlur:





Saturday, December 1, 2012

Notes before rendering

  • Make sure Ray Traced motion blur is unchecked (under Render Settings>Features)
  • Add these RenderMan attributes to cliff geometry:
    • Subdiv Scheme
    • Trace Bias: 0.1
    • Trace Displacement: All

Tuesday, November 20, 2012

Passes for Rendering

Passes
  • Beauty
  • Ambient Occlusion
  • Z-depth
  • Any effects necessary for shot

Masks (Siran will update us on how to do this):
  • Gus
  • Flag


Environment Light settings

Colorbleeding (also used to calculate ambient occlusion)
Environment color: black
Intensity: 1.0
ONLY emit diffuse
Bake Shadowing: RenderRadiosity (check settings two posts down)
Environment Sampling Mode: Sampled
Samples: 512
Max Variation: 0.5 (IMPORTANT! This will take out all the ugly square artefacts in ambient occlusion pass)
Max Distance: 50 - 100 (depends on how your ambient occlusion looks)
Falloff Mode: maxdist-based

Spec

Environment image: hdr_mountains1.exr (found in light-vdev_rig>light-vdev_rig.proj>sourceimages)
Intensity: 1.0
ONLY emit specular
everything else the same EXCEPT...
Max Dist: measure from Gus to environment light 
Max Variation can also be taken up to 2.0