materials

Materials

Materials are built with Cycles nodes.

Table of Content

• Displacement
• Blending
• Transparency
• Material parameters
• Shader uniforms
  • Available uniforms

Displacement

Locate the Armory Render Path - Renderer - Displacement property:

• Off - No displacement performed
• Vertex - Mesh vertices are displaced
• Tessellation - Mesh is first tessellated for more detail and then displaced

With Tessellation selected, the level of tessellation can be set using the Mesh and Shadow property.

Note: Vertices are displaced in normals direction. Use smooth shading (Space - Shade Smooth) for meshes with displacement to prevent gabs.

Examples:

• https://github.com/armory3d/armory_examples/tree/master/material_examples

Blending

To enable additive blending for specific material, set Armory Render Path - Blending to On and check the Blending property in Material - Armory Props.

Examples:

• https://github.com/armory3d/armory_examples/tree/master/material_translucent
• https://github.com/armory3d/armory_examples/tree/master/particle_examples

Transparency

• Connect an alpha map to the Principled BSDF input of a material.
• Material properties: Armory Props: Uncheck Alpha Test.

Material parameters

RGB, Value and Image Texture material nodes can be controlled at run-time using script or logic nodes. To expose material node, enable Parameter property in Node Editor - Properties - Armory Material Node.

Examples:

• https://github.com/armory3d/armory_examples/tree/master/material_params

Shader uniforms

It is possible to retrieve additional light and scene data via uniforms. There are two different ways of using them:

• Using material nodes:

  It is possible to access uniform values with the Attribute node. To do this, write something in the form <uniformType> <linkName> into the string input field of the node. <uniformType> must be replaced with vec2, vec3, vec4, int or float, so only uniforms of those types are supported by the Attribute node. Replace <linkName> with the name of the link (e.g. "_pointPosition") that can be found in Available uniforms.

  Please note that there is no viewport preview for uniform values!

  Example:
  

• Custom materials:

  To pass a uniform to the fragment shader, add an entry in the material definition (example) under "shader_datas" > "contexts" > "constants":

  {
      "link": "<linkName>",
      "name": "<uniformName>",
      "type": "<uniformType>"
  }

  Replace <linkName> with the name of the link (e.g. "_pointPosition") that can be found in Available uniforms and replace <uniformName> and <uniformType> according to your fragment shader.

Available uniforms

(The following tables are not yet complete, please look into Uniforms.hx for all available uniforms).

Camera:

Link name	Type	Description
_cameraPosition	vec3	World position of the active camera
_cameraLook	vec3	Normalized look vector of the active camera in world coordinates
_cameraUp	vec3	Normalized up vector of the active camera in world coordinates
_cameraRight	vec3	Normalized right vector of the active camera in world coordinates
_fieldOfView	vec3	Field of view of the active camera
_viewMatrix	mat4	View matrix of the active camera
_transposeViewMatrix	mat4	View matrix of the active camera with rows and columns 0-2 (3x3) transposed
_projectionMatrix	mat4	Projection matrix of the active camera
_inverseProjectionMatrix	mat4	Inverse of the projection matrix of the active camera
_viewProjectionMatrix	mat4	View matrix multiplied with the projection matrix of the active camera
_inverseViewProjectionMatrix	mat4	View matrix multiplied with the projection matrix of the active camera and inversed
_prevViewProjectionMatrix	mat4	_viewProjectionMatrix from the previous frame

Lights:

Link name	Type	Description
_lightDirection	vec3
_lightPosition	vec3
_pointPosition	vec3
_pointColor	vec3
_sunColor	vec3
_sunDirection	vec3
_spotDirection	vec3
_lightArea0 - _lightArea3	vec3

World:

Link name	Type	Description
_backgroundCol	vec3	The background color of the current world. (0, 0, 0) if not set
_envmapStrength	float	The strength of the world background. 0 if the scene has no world

Other:

Link name	Type	Description
_time	float	The elapsed time since the beginning of the game