Set Parameter - Arnold Render in Houdini

[Mario3d]

Hi, Im trying to create different overrides for diferent arnold render_out nodes, like takes, or like the render setup in Maya, I know I can use the option of use phantom object or matte in the arnold_out node, but is more powerfull to use overrides, it give us the possibility to override more properties like cast shadows, recieve shadows...etc (I dont know this names exactly right now). The thing is I go to out, and I create a node Set_parameter (arnold node) and I conect this to an Arnold_OUT, in the Set_Parameter I  create the path for the section I want to override, in this case is an geometry node (selection: obj/geo1/*) inside for example I put a box for testing, and next I write the attribute I want to override, in this case I want to override the arnold parameter from geometry, in this case I write...for example...

subdiv_type = "catclarck"

subdiv_iterations = 3

 

ok, this two parameter are working for me, when I activate that arnold rendere node to render, that parameter change and I can watch it in the render, even also work for me this parameter override:

 

matte = True

 

but, and here is my problem, I really want to override the visibility tab arnold parameter, like visibility rays to camera, self shadows an so on...but I cant it work, in this case I write...

 

visibility_camera = False

 

and this last one no work for me, how can I do for this work??? (visibility_camera for example), I only go to the parameter in geometry, arnold, visibility tab and I let the mouse over the parameter, and in the floating window I can watch the parameter, in this case is ar_visibility_camera  but I thing for use this attribute we have to remove the ar_   , but event with this I cant get the override for visibility.

 

 

I let here the official Arnold web site with Set parameter info...

https://docs.arnoldrenderer.com/display/A5AFHUG/Set+Parameter

 

Thanks.

 

[schwungsau]

you should install arnold sdk then can use the kick command to get more info

"kick -info polymesh"
 

node:         polymesh
type:         shape
output:       (null)
parameters:   48
filename:     <built-in>
version:      6.0.2.0

Type          Name                              Default
------------  --------------------------------  --------------------------------
BYTE          visibility                        255
BYTE          sidedness                         255
BOOL          receive_shadows                   true
BOOL          self_shadows                      true
BOOL          invert_normals                    false
FLOAT         ray_bias                          1e-06
MATRIX[]      matrix                            (empty)
ENUM          transform_type                    rotate_about_center
NODE[]        shader                            (empty)
BOOL          opaque                            true
BOOL          matte                             false
BOOL          use_light_group                   false
NODE[]        light_group                       (empty)
BOOL          use_shadow_group                  false
NODE[]        shadow_group                      (empty)
STRING[]      trace_sets                        (empty)
FLOAT         motion_start                      0
FLOAT         motion_end                        1
UINT          id                                0
UINT[]        nsides                            (empty)
UINT[]        vidxs                             (empty)
UINT[]        polygon_holes                     (empty)
UINT[]        nidxs                             (empty)
UINT[]        uvidxs                            (empty)
UINT[]        crease_idxs                       (empty)
FLOAT[]       crease_sharpness                  (empty)
BYTE[]        shidxs                            (empty)
VECTOR[]      vlist                             (empty)
VECTOR[]      nlist                             (empty)
VECTOR2[]     uvlist                            (empty)
BOOL          smoothing                         false
ENUM          subdiv_type                       none
BYTE          subdiv_iterations                 1
FLOAT         subdiv_adaptive_error             0
ENUM          subdiv_adaptive_metric            auto
ENUM          subdiv_adaptive_space             raster
BOOL          subdiv_frustum_ignore             false
ENUM          subdiv_uv_smoothing               pin_corners
BOOL          subdiv_smooth_derivs              false
NODE[]        disp_map                          (empty)
FLOAT         disp_padding                      0
FLOAT         disp_height                       1
FLOAT         disp_zero_value                   0
BOOL          disp_autobump                     false
BYTE          autobump_visibility               1
FLOAT         step_size                         0
FLOAT         volume_padding                    0
STRING        name

 

[schwungsau]

visiblity is a bitmask.

In decimal:

• AI_RAY_CAMERA = 1
• AI_RAY_SHADOW = 2
• AI_RAY_DIFFUSE_TRANSMIT = 4
• AI_RAY_SPECULAR_TRANSMIT = 8
• AI_RAY_VOLUME = 16
• AI_RAY_DIFFUSE_REFLECT = 32
• AI_RAY_SPECULAR_REFLECT = 64
• AI_RAY_SUBSURFACE = 128

So visiblity = 13 gives you camera and transmission (1 + 4 + 8 = 13 )