Work with Material Nodes

Using Lua to interact with material nodes

Materials describe the appearance of models in the scene.

Properties

Property	Type	Description
Diffuse	vrvec3	Main material colour, RGB values (0.0 - 1.0)
Reflectivity	number	How reflective the material is (0.0 - 1.0)
Smoothness	number	How smooth the material is (0.0 - 1.0)
Metalness	number	How metallic the material is (0.0 - 1.0)
Ambient	number	How much ambient light the material reflects (0.0 - 1.0)
Emissive	vrvec3	The colour emitted by the material, RGB values (0.0 - 1.0)
EmissiveIntensity	number	Emissive multiplier (0.0 - 10000.0)
Opacity	number	How opaque the material is (0.0 - 1.0). Values other than 1 require BlendMode to be set to something other than None.
DiffuseMap	vrnode	Link to colour texture in the tree
SmoothnessMap	vrnode	Link to monochrome texture in the tree
ReflectivityMap	vrnode	Link to monochrome texture in the tree
AmbientMap	vrnode	Link to monochrome texture in the tree
EmissiveMap	vrnode	Link to colour texture in the tree
OpacityMap	vrnode	Link to monochrome texture in the tree
EnvironmentMap	vrnode	Link to colour texture in the tree
NormalMap	vrnode	Link to colour texture in the tree
BumpMap	vrnode	Link to colour texture in the tree
Enabled	boolean	Enabled or disabled (when disabled, any objects using this material are not rendered)
BlendMode	number	Which blend mode to use. See the blend mode table below.
AlphaTest	boolean	Whether to enable alpha testing
AlphaTestRef	number	The opacity value below which the fragment is discarded
AlphaToCoverage	boolean	Whether to enable screendoor transparency
BumpScale	number	Scales the bump or normal map (0.0 - 20.0)
ReliefMapping	boolean	Whether to enable relief mapping
TwoSidedLighting	boolean	Whether to enable two sided lighting for objects using this material
MapMatrix	vrmatrix4	Transform to apply to texture coordinates on objects that this material is applied to
LineWidth	number	Specify the width of lines drawn with this material (0.0 - 20.0)
LinePattern	number	The pattern to use to draw lines. See the line pattern table below.
Lit	boolean	Specify whether this material is affected by scene lighting
NightEmissive	boolean	Specify whether this material is affected by night time
HalfLambert	boolean	Specify whether to use half lambert diffuse lighting mode
PreviewShape	vrnode	Specify a custom shape (Model node) to use to preview this material, instead of the default sphere

Blend Modes

Type	Description
__StdMaterial_BlendNone	No alpha blending at all (Opacity property changes have no effect)
__StdMaterial_BlendAlpha	Alpha blending
__StdMaterial_BlendAdditive	Additive blending
__StdMaterial_BlendMultiplicative	Multiplicative blending

Line Patterns

Type	Description
__StdMaterial_LinePatternFullLine	Draws solid lines
__StdMaterial_LinePatternNoLine	Doesn't draw lines at all
__StdMaterial_LinePatternDoubleDashed	Draws double-dashed lines
__StdMaterial_LinePatternDashedLine	Draws dashed lines

Examples

Example 1

This script will change the opacity value (0.0 to 1.0) of the material pointed to by the variable HighLight. The HighLight variable points at the Material assembly within the Library tree view. When the opacty level if greater than or equal to 1.0 it then begins to decrement the opacity level. If the opacity level is less than or equal to 0.0 it then increments the opacity level.

-- Drag/Drop section BEGINS - Do not edit between BEGINS and ENDS.
local Highlight = __Script.dragdrop.Highlight
local Delta = __Script.dragdrop.Direction
-- Drag/Drop section ENDS

-- Highlight is a StdMaterial node
-- Delta is a MetaDataFloat node

print("Material ", Highlight)
print("Colour ", Highlight.Diffuse)
print("Ambient ", Highlight.Ambient)
print("Opacity ", Highlight.Opacity)
print("Smoothness ", Highlight.Smoothness)
print("Metalicness ", Highlight.Metalness)
print("Reflectivity ", Highlight.Reflectivity)

-- initialise the delta variable
if Delta.Value == 0 then
   Delta.Value = 0.1
end

-- get the material opacity
local opacity = Highlight.Opacity

-- update the opacity depending on direction
opacity = opacity + Delta.Value

-- check the opacity value is not beyond the limits
if opacity <= 0.0 then
   Delta.Value = 0.1
   opacity = 0.0
elseif opacity >= 1.0 then
   Delta.Value = -0.1
   opacity = 1.0
end

-- set the new opacity value
Highlight.Opacity = opacity

Example 2

Simple script which changes the Emissive value of the material pointed to by the Chess_table variable. The Emissive value is defined in an array of 3 floating point number between 0.0 and .0 for the red, green and blue components.

-- Drag/Drop section BEGINS - Do not edit between BEGINS and ENDS.
local table = __Script.dragdrop.table
-- Drag/Drop section ENDS

-- get Emissive colour
local emissive = table.Emissive

-- set material Diffuse to same as emissive
table.Diffuse = emissive

-- set emissive RGB values
emissive[1] = 0.0
emissive[2] = 1.0
emissive[3] = 0.0

-- print the DiffuseMap link
print(table.DiffuseMap)

-- print the DiffuseMap filename
print(table.DiffuseMap.Filename)

Example 3

This example demonstrates how to change how a texture is mapped onto a surface by modifying the MapMatrix. The MapMatrix is a 3x3 matrix which is applied to the texture coordinates of the assembly it is applied to. This is accessed using the same method as the Assembly Transform.

-- Drag/Drop section BEGINS - Do not edit between BEGINS and ENDS.
local table = __Script.dragdrop.table
-- Drag/Drop section ENDS

-- increment the Y offset position by 0.01
table.MapMatrix.Position.Y = table.MapMatrix.Position.Y + 0.01