SoGVRIlluminationSettings¶

InventorModule¶

genre	`VolRendExtensions`
author	`MeVis Medical Solutions AG`
package	`MeVisLab/Standard`
dll	`SoGVR`
definition	soGVR.def
see also	`SoGVRVolumeRenderer`

Purpose¶

The SoGVRIlluminationSettings module allows to overwrite the settings for the Illuminated render mode of the SoGVRVolumeRenderer module. The same fields are also available in the SoGVRVolumeRenderer panel (see “Illumination”) and are documented on this help page as well.

This module can also override the blend mode and the render mode. Using this module, the same renderer can use various render settings in different Open Inventor scenes.

Usage¶

The SoGVRIlluminationSettings module allows to overwrite the settings for the Illuminated render mode of the SoGVRVolRen module. The same fields are also available in the SoGVRVolRen panel (see “Illumination”) and are documented on this help page as well.

The Illuminated mode is an advanced render mode that allows to set the following shading/lighting properties:

1-3 colored directional lights (using Blinn-Phong lighting)

Tone Shading

Boundary Enhancement

Silhouette Enhancement

The Illuminated mode supports an additional SoGVRTagVolume and an additional SoGVRMaskVolume.

Details¶

The Illuminated mode is a render mode that allows to set the following shading/lighting properties:

1-3 colored directional lights (using Blinn-Phong lighting)
Tone Shading
Boundary Enhancement
Silhouette Enhancement

Tips¶

When multiple lights or tone shading are enabled and you image gets too bright, set the Ambient field to a lower value! See the example network for useful shader settings.

Windows¶

Default Panel¶

../../../Modules/Inventor/SoGVR/mhelp/Images/Screenshots/SoGVRIlluminationSettings._default.png

Material (affects all 3 lights)¶

Ambient:: defines the ambient material property of the volume data (0 means no ambient light, 1 means full ambient light)
Diffuse:: defines the diffuse material property of the volume data (0 means no diffuse light, 1 mean full diffuse light)
Specular:: defines the specular material property of the volume data (0 means no specular light, 1 means full specular light)
Specularity:: defines the specularity of the object, a higher value leads to a smaller highlight

Light 1-3¶

For detail on the Blinn/Phong lighting model, see http://www.lighthouse3d.com/opengl/glsl/index.php?ogldir2

Enabled:: enables the directional light
Diffuse Intensity:: sets this light’s diffuse intensity, 0 means no diffuse light
Specular Intensity:: sets this light’s specular intensity, 0 means no specular highlights
Color:: sets the color of the light
Azimuth, Altitude:: sets the position of the light in polar coordinates, 0/0 is front facing headlight

Tone Shading¶

For details on tone shading, see http://www.cs.utah.edu/~gooch/SIG98/abstract.html This model is based on using warm and cold colors for illumination and allows nice coloring of renderings of e.g. Bones, Vessels etc.

Enabled:: enables tone shading
Warm/Cold Color:: defines the color used as warm/cold color
Warm/Cold Diffuse:: defines how much diffuse light should be applied
Angle:: defines the angle of the tone shading, rotates around the viewing direction

Enhancement¶

The GVR supports gradient based enhancement as described in http://www.cs.umbc.edu/~rheingan/pubs/volillus00.pdf

Boundary Enhancement¶

This mode is based on the gradient strenght (normalized to 0-1) and affects the opacity/alpha values of the rendered voxel by weighting with the gradient strenght.

Enabled:: enables boundary enhancement
Weight:: defines the weight factor that is applied
Exponent:: defines the exponent that is applied
Bias:: defines the gradient strength bias

The enhancement is calculated like this:

alpha = alpha * weight * pow( gradientStrength + bias, exponent)

Silhouette Enhancement¶

This mode also affects the opacity of voxels by weighting them with the angle between the voxel gradient and the viewing direction. This makes voxels that face the viewer transparent, while making voxels that are perpendicular to the viewer opaque, see above paper for the used formula.

Enabled:: enables sihouette enhancement
Weight:: defines the weight factor that is applied
Exponent:: defines the exponent that is applied

For both modes:

Add Original Alpha:: defines how much of the original alpha is added to the alpha value after enhancement

Output Fields¶

self¶

name: self, type: SoNode¶: a node that should be put in front of the SoGVRVolumeRenderer

Parameter Fields¶

Field Index¶

`Add Original Alpha`: `Float`	`Color (light2Color)`: `Color`	`Exponent (silhouetteEnhancementExponent)`: `Float`
`Altitude (light1PolarRho)`: `Float`	`Color (light3Color)`: `Color`	`Reduce Lighting On Low Gradient Magnitude`: `Bool`
`Altitude (light2PolarRho)`: `Float`	`Diffuse`: `Float`	`Render Mode`: `Enum`
`Altitude (light3PolarRho)`: `Float`	`Diffuse Intensity (light1DiffuseIntensity)`: `Float`	`Specular`: `Float`
`Ambient`: `Float`	`Diffuse Intensity (light2DiffuseIntensity)`: `Float`	`Specular Intensity (light1SpecularIntensity)`: `Float`
`Angle`: `Float`	`Diffuse Intensity (light3DiffuseIntensity)`: `Float`	`Specular Intensity (light2SpecularIntensity)`: `Float`
`Azimuth (light1PolarPhi)`: `Float`	`Enabled (enabled)`: `Bool`	`Specular Intensity (light3SpecularIntensity)`: `Float`
`Azimuth (light2PolarPhi)`: `Float`	`Enabled (boundaryEnhancement)`: `Bool`	`Specularity`: `Float`
`Azimuth (light3PolarPhi)`: `Float`	`Enabled (silhouetteEnhancement)`: `Bool`	`Warm Color`: `Color`
`Bias`: `Float`	`Enabled (toneShading)`: `Bool`	`Warm Diffuse`: `Float`
`Blend Mode`: `Enum`	`Enabled (light1Enabled)`: `Bool`	`Weight (boundaryEnhancementFactor)`: `Float`
`Cold Color`: `Color`	`Enabled (light2Enabled)`: `Bool`	`Weight (silhouetteEnhancementFactor)`: `Float`
`Cold Diffuse`: `Float`	`Enabled (light3Enabled)`: `Bool`
`Color (light1Color)`: `Color`	`Exponent (boundaryEnhancementExponent)`: `Float`

Visible Fields¶

Enabled (enabled)¶

name: enabled, type: Bool, default: TRUE¶: Enables the settings given in this module.

Add Original Alpha¶

name: enhancementAlphaMix, type: Float, default: 0.25, minimum: 0, maximum: 1¶: defines how much of the original alpha is mixed to the enhancement

Enabled (boundaryEnhancement)¶

name: boundaryEnhancement, type: Bool, default: FALSE¶: Enables boundary enhancement

Weight (boundaryEnhancementFactor)¶

name: boundaryEnhancementFactor, type: Float, default: 1, minimum: 0, maximum: 50¶: Defines the weight for the boundary enhancement.

Exponent (boundaryEnhancementExponent)¶

name: boundaryEnhancementExponent, type: Float, default: 1, minimum: 0.1, maximum: 50¶: defines the boundary enhancement exponent

Bias¶

name: boundaryEnhancementGradientBias, type: Float, default: 0, minimum: -1, maximum: 1¶: defines the bias for boundary enhancement

Enabled (silhouetteEnhancement)¶

name: silhouetteEnhancement, type: Bool, default: FALSE¶: enables silhouetteEnhancement

Exponent (silhouetteEnhancementExponent)¶

name: silhouetteEnhancementExponent, type: Float, default: 1, minimum: 0.1, maximum: 50¶: defines the silhouetteEnhancementExponent

Weight (silhouetteEnhancementFactor)¶

name: silhouetteEnhancementFactor, type: Float, default: 1, minimum: 0, maximum: 20¶: Defines the weight for the silhouette enhancement.

Enabled (toneShading)¶

name: toneShading, type: Bool, default: FALSE¶: enables tone shading

Warm Color¶

name: toneShadingWarmColor, type: Color, default: 0.674509823322296 0.533333361148834 0.141176477074623¶: Defines the warm color of the tone shading.

Cold Color¶

name: toneShadingColdColor, type: Color, default: 0 0 0.400000005960464¶: cold color of tone shading

Warm Diffuse¶

name: toneShadingWarmDiffuse, type: Float, default: 0.60000002, minimum: 0, maximum: 1¶: Defines the warm diffuse factor of the tone shading

Cold Diffuse¶

name: toneShadingColdDiffuse, type: Float, default: 0.2, minimum: 0, maximum: 1¶: diffuse light of cold color

Angle¶

name: toneShadingAngle, type: Float, default: 45, minimum: -180, maximum: 180¶: Defines the angle of the tone shading.

Ambient¶

name: materialAmbient, type: Float, default: 0.60000002, minimum: 0, maximum: 1¶: defines the ambient light

Diffuse¶

name: materialDiffuse, type: Float, default: 1, minimum: 0, maximum: 1¶: overall diffuse factor for all lights

Specular¶

name: materialSpecular, type: Float, default: 1, minimum: 0, maximum: 1¶: Defines the overall specular intensity for all lights.

Specularity¶

name: materialSpecularity, type: Float, default: 32, minimum: 1, maximum: 128¶: Defines the specularity exponent of the lights.

Reduce Lighting On Low Gradient Magnitude¶

name: reduceLightingOnLowGradientMagnitude, type: Bool, default: FALSE¶: Reduces the lighting on low gradient magnitudes.

Enabled (light1Enabled)¶

name: light1Enabled, type: Bool, default: TRUE¶: enables light1

Diffuse Intensity (light1DiffuseIntensity)¶

name: light1DiffuseIntensity, type: Float, default: 1, minimum: 0, maximum: 1¶: diffuse intensity of light1

Specular Intensity (light1SpecularIntensity)¶

name: light1SpecularIntensity, type: Float, default: 1, minimum: 0, maximum: 1¶: Defines the specular intensity for light1.

Color (light1Color)¶

name: light1Color, type: Color, default: 1 1 1¶: color of light1

Azimuth (light1PolarPhi)¶

name: light1PolarPhi, type: Float, default: 0, minimum: -180, maximum: 180¶: Defines the light angle.

Altitude (light1PolarRho)¶

name: light1PolarRho, type: Float, default: 0, minimum: -180, maximum: 180¶: Defines the light angle.

Enabled (light2Enabled)¶

name: light2Enabled, type: Bool, default: FALSE¶: enables light2

Diffuse Intensity (light2DiffuseIntensity)¶

name: light2DiffuseIntensity, type: Float, default: 1, minimum: 0, maximum: 1¶: diffuse intensity of light2

Specular Intensity (light2SpecularIntensity)¶

name: light2SpecularIntensity, type: Float, default: 1, minimum: 0, maximum: 1¶: Defines the specular intensity for light2.

Color (light2Color)¶

name: light2Color, type: Color, default: 1 1 1¶: color of light2

Azimuth (light2PolarPhi)¶

name: light2PolarPhi, type: Float, default: 45, minimum: -180, maximum: 180¶: Defines the light angle.

Altitude (light2PolarRho)¶

name: light2PolarRho, type: Float, default: 45, minimum: -180, maximum: 180¶: Defines the light angle.

Enabled (light3Enabled)¶

name: light3Enabled, type: Bool, default: FALSE¶: enables light3

Diffuse Intensity (light3DiffuseIntensity)¶

name: light3DiffuseIntensity, type: Float, default: 1, minimum: 0, maximum: 1¶: diffuse intensity of light3

Specular Intensity (light3SpecularIntensity)¶

name: light3SpecularIntensity, type: Float, default: 1, minimum: 0, maximum: 1¶: Defines the specular intensity for light3.

Color (light3Color)¶

name: light3Color, type: Color, default: 1 1 1¶: color of light3

Azimuth (light3PolarPhi)¶

name: light3PolarPhi, type: Float, default: -45, minimum: -180, maximum: 180¶: Defines the light angle.

Altitude (light3PolarRho)¶

name: light3PolarRho, type: Float, default: 0, minimum: -180, maximum: 180¶: Defines the light angle.

Render Mode¶

name: renderMode, type: Enum, default: Illuminated¶: Sets the used render mode.

Values:

Title	Name	Description
Direct	Direct	Direct Volume Rendering
Illuminated	Illuminated	Illuminated/Shaded Volume Rendering (see Illumination tab).
Mip	MIP

Blend Mode¶

name: blendMode, type: Enum, default: Blend¶: selects the blend mode that is used