Simple Snow Material in VRay for 3ds max

Software:
3ds max 2019 | V-Ray Next

A simple way to create a snow material in V-Ray for 3ds max is to combine a VRayFastSSS2 material with a VRayFlakesMtl using a VRayBlendMtl.
The VRayFastSSS2 creates the soft translucent shading for the snow, and the VRayFlakesMtls adds sparkling highlights.

  • Note that depending on the scene and view scale,
    The VRayFlakesMtls ‘flake glossiness’, ‘flake density’ and ‘flake size’ have to be tweaked to achieve the wanted result.

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3ds max Island / Seashore opacity underwater tip

Software:
3ds max 2016

When creating a surface submerged in sea water,
Theoretically, it’s the Volume Absorption or ‘Fog‘ of the water shader that should do cause the surface to disappear under water.
But in many cases that doesn’t work well because we don’t actually model enough extended surface under the water for it to completely disappear without seeing the surfaces geometric edges that spoil the result.

One of the oldest tricks in the book is to use a Gradient Ramp map in the surface’s Opacity channel to make it gradually disappear before the geometry ends.

This can be done in most  3d software and render engines, I’m demonstrating it here using 3ds max and V-Ray:

Island

 

Customizable Photo-realistic Car-paint shader for Cycles

Software:
Blender 2.8 | Cycles Render

CGL Car Paint Presets Pack 1.0 is a highly customizable photo-realistic car-paint shader I developed for Blender & the Cycles render engine.
The shader has built-in realistic effects like color blending, metallic flakes, clear-coat etc.
And ships with 32 ready-to-use real world car paint material presets.

CGL Car Paint Presets Pack 1.0 is available on Blender Market:
https://www.blendermarket.com/products/cg-lion-car-paint-presets-pack-1

CGL_CarPaint.jpg

CGL_Cycles_Car_Paint_Presets_Pack_1.0_No_Numbers

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Related posts:
Realistic Spotlights for Blender & Cycles
Complex Fresnel texture for Cycles

Python for 3ds max – Mesh manipulation

Software:
3ds max 2019

An example of creating a mesh ripple deformation using Python for 3ds max:

mesh_manipulation.gif

Script steps:

  1. Define the effect intensity and a helper point object that will serve as the effect center.
  2. Collapse the object to an Editable-Mesh so its vertices will be accessible by Python.
    Note that the Node‘s Object has to be cast as a TriObject, to access the object’s Mesh data.
  3.  Loop through the Mesh’s vertices, get their world position, and set a new Z position as a sine function of the distance from the effect center.
import math
from MaxPlus import Factory
from MaxPlus import ClassIds
from MaxPlus import INode
from MaxPlus import TriObject
from MaxPlus import Matrix3
from MaxPlus import Point3

# Intensity:
effecr_mult = 1.0

# Effect center:
effector = INode.GetINodeByName('Point001')
effect_pos = effector.GetWorldPosition()

# Prepare object and eccess it's mesh data:
node = INode.GetINodeByName('Teapot001')
new_edit_mesh_mod = Factory.CreateObjectModifier(ClassIds.Edit_Mesh)
node.AddModifier(new_edit_mesh_mod)
node.Collapse(True)
node_tm = node.GetWorldTM()
node_pos = node.GetWorldPosition()
obj = node.GetObject()
triobj = TriObject._CastFrom(obj)
mesh = triobj.GetMesh()

# Process the object's vertices:
for i in range(mesh.GetNumVertices()):
     # Get vertex in world space
     vert_pos = mesh.GetVertex(i)
     vert_world_pos = node_tm.VectorTransform(vert_pos)
     vert_world_pos = vert_world_pos + node_pos
     # Get vertex distance from effect center:
     diff_vec = vert_world_pos - effect_pos 
     diff_vec.Z = 0
     dist = diff_vec.GetLength()
     # Set new vertex position:
     mesh.SetVert(i,vert_pos.X,vert_pos.Y,vert_pos.Z + math.sin(dist)*effecr_mult)

* note that when copying and pasting a script from this example, the indentation may not be pasted correctly.

Related Post:
Python for 3ds max – Animated Mesh

Python for 3ds max – Animated Mesh

Software:
3ds max 2019

This is an example of procedurally animating a mesh’s vertices via Python script.

Vert_Anim.gif

Notes:
1. The model has to be converted to Editable Mesh before the script is run.
* unless the scrip will be extended to do it.
2. The model must be selected for the script to work.

import MaxPlus
import math
from MaxPlus import INode
from MaxPlus import TriObject
from MaxPlus import SelectionManager
from MaxPlus import Factory
from MaxPlus import Animation
from MaxPlus import Point3
from MaxPlus import Control

ticks_frame = 160

#Selection
sel = []
for n in SelectionManager.Nodes:
    sel.append(n)
node = sel[0]

#Setup Controllers
obj = node.GetObject()
Tri = TriObject._CastFrom(obj)
mesh = Tri.GetMesh()
num_verts = mesh.GetNumVertices()
mesh_anim = obj.GetSubAnim(0)
pnt_ctrl = Factory.CreateDefaultMasterPointController()
node.AssignController(pnt_ctrl,1)
for i in range(num_verts):
    bezp3 = Factory.CreateDefaultPoint3Controller()
    bezp3.SetPoint3Value(mesh.GetVertex(i))
    mesh_anim.AssignController(bezp3,i)

#Animation
Animation.SetAnimateButtonState(True)
for t in range(100):
    time = t * ticks_frame
    Animation.SetTime(time)
    mesh_anim.AddNewKey(time,0)
    for i in range(num_verts):
        vert_anim = mesh_anim.GetSubAnim(i)
        vert_ctrl = Control._CastFrom(vert_anim)
        vert_val = mesh.GetVertex(i)
        vert_val.SetZ(vert_val.GetZ() + math.sin(((Animation.GetTime()*0.5)/(ticks_frame))+i))
        vert_ctrl.SetPoint3Value(vert_val)
Animation.SetAnimateButtonState(False)

* note that when copying and pasting a script from this example, the indentation may not be pasted correctly.

Related:
Python for 3ds max – Mesh manipulation

V-Ray – Underwater rendering tip

Software:
3ds max 2019 | V-Ray Next

I decided to do some test renders for an underwater swimming pool scene with 3ds max and V-Ray,
And happily found out that my initial geeky academic approach to the subject was actually outdated and unnecessary.
> look down at the bottom for the correct sample renders.

In this example there is a VRaySun & VRaySky for the daylight render setup and a Caustics calculation to create the light lensing effects on the under water surfaces.

The wrong way:
Having ancient habits in the subject,
I first flipped the water\air surface’s normals so they’ll point down into the water (towards the camera), And set the water material’s IOR to 0.75 ( 1 / 1.333 ) so instead of being an “air to water” material, it will become a “water to air” material.
This produced a non realistic result.
Viewed from underwater, the air surface should have a very dominant mirror reflection at most angles.Untitled-1.jpg

 

The Correct Way:
It seems that in V-Ray nothing special should be setup in terms of the water material.
You don’t have to create a special water-to-air material like I thought at first.
Its a regular water material, and the water surface is facing upwards like it should,
And when the camera is underwater it renders the water surface correctly as an air surface from withing the water.

The pool water material setup:
Note that Affect Shadows is turned off so the surface will generate caustics and not fake transparent shadows, and that Reflect on back side is turned on to produce more detailed reflections.
mat.jpg

This produced the following result in which the reflection/refraction look correct but the water is still too simple:Untitled-2.jpg

Improved wave deformation for the water surface, added detail using a Noise bump in the water material and a sense of depth with Volumetric Fog:Untitled-4.jpg

Finally remembered to activate Reflect on back side at the water material to add more realistic reflection detail, some basic contrast in the V-Ray VFB,
And a shark because I couldn’t help it…. 😀
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Getting Maya 3D Paint to work

Software:
Maya 2018

Steps needed for Maya 3D Paint to work:

  1. Set a project folder and save your scene.
    * If your painting into an existing texture you can skip this step.
  2. Make sure your model has UV coordinates.
  3. Make sure your model has a basic Lambert material.
    * If you’re using a different material/shader on your model,
    Temporarily switch to Lambert just for the texture painting operation,
    And connect the original shader with the painted texture map to the surface shader input of the shading group after you’re done painting.
  4. In the Rendering tab toolbar, Double-Click the 3D Paint tool button to activate 3D Paint and also open its tool settings window.
  5. Make sure the object is selected.
  6. In the 3D Paint Settings window, go to the File Textures part,
    Choose a material attribute to paint to.
    * this would usually be Color because we are using Lambert temporarily anyway.
  7. Click Assign/Edit Textures to open the Assign/Edit Textures dialog,
    Choose a resolution and a file format for the new texture,
    And than click Assign/Edit Textures button at the bottom of the Assign/Edit Textures dialog to create the new texture and close the dialog.
    * If you already connected an existing texture file to the Lambert shader’s Color input you can skip this step.
  8. Check Update on stroke and Save texture on stroke.
  9. Set the viewport to Textured display mode.
  10. Set paint brush settings.
  11. Click the 3D Paint tool button to activate it and paint on the model surface.

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