Class SoVolumeRenderingQuality
- java.lang.Object
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- com.openinventor.inventor.Inventor
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- com.openinventor.inventor.misc.SoBase
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- com.openinventor.inventor.fields.SoFieldContainer
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- com.openinventor.inventor.nodes.SoNode
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- com.openinventor.inventor.nodes.SoShaderProgram
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- com.openinventor.volumeviz.nodes.SoVolumeShader
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- com.openinventor.volumeviz.nodes.SoVolumeRenderingQuality
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- All Implemented Interfaces:
SafeDisposable
public class SoVolumeRenderingQuality extends SoVolumeShader
Volume rendering quality property mode. This property node causes subsequentSoVolumeRender
nodes to be drawn with different rendering effects and/or levels of quality.NOTE:
- Only one (or none) of the following nodes can be active at a time:
SoVolumeShader
orSoVolumeRenderingQuality
. However since Open Inventor 7.1, bothSoVolumeRenderingQuality
andSoVolumeIsosurface
may applied to the sameSoVolumeRender
node. - If the application simply needs to replace one or more of the VolumeViz shader rendering functions with a customized shader, you can use either
SoVolumeShader
orSoVolumeRenderingQuality
. However if the application needs the advanced rendering features ofSoVolumeRenderingQuality
, e.g. lighting, in addition to the customized behavior, then you should use this node (which is derived fromSoVolumeShader
). Using the shader rendering framework is explained on theSoVolumeShader
page. - The
SoVolumeRenderingQuality
node must be before theSoVolumeRender
and after theSoTransferFunction
. - This is a shader node!
The effect will usually be undesirable if it is applied to standard geometry (polygons, lines, etc). Therefore applications should generally keep the volume visualization nodes and standard geometry nodes separate in the scene graph (i.e. under differentSoSeparator
nodes). - Please read the comments for each field.
Some options only apply to gradient lighting and have no effect on deferred lighting.Pre-integrated and lighted rendering Various enhanced rendering modes for volume rendering are available:
- Pre-integrated volume rendering
- Lighted volume rendering
The pre-integrated mode (
preIntegrated
field) generally provides higher image quality for the same number of slices. Most applications should enable this field. However, note that pre-integration integrates between color map values. For typical scalar data containing sampled values, this provides a beneficial smoothing. It is especially useful when the color changes sharply between adjacent color map entries. However, when the color changes sharply between adjacent voxels, it can can cause values that are not actually in the original data to be displayed. This is undesireable for some data, for example "label" volumes resulting from segmentation. Pre-integration is not recommended for such data. Also note:- The
preIntegrated
field has no effect onSoVolumeIsosurface
rendering. - The
preIntegrated
field is only considered when SoVolumeRendering.renderMode is set to VOLUME_RENDERING (the default).
When lighting is enabled for volume rendering, VolumeViz applies the same lighting equation used for polygonal geometry, including (optionally) specular highlights. The base voxel color comes from the
SoTransferFunction
node or (optionally) from a custom shader function provided by the application. This color is modified using the current material (SoMaterial
), a vector simulating a "normal vector" and one or more directional light nodes (SoDirectionalLight
) found in the scene graph. Voxels can also cast and receive shadows (seeSoShadowGroup
).Limitation: Pre-integrated and lighted rendering are not supported if using custom fragment shaders and redefining FRAGMENT_COMPUTE_COLOR slot.
VolumeViz supports two lighting modes using either the
lighting
field or thedeferredLighting
field. In both cases lighting is computed on the GPU as part of the rendering process. (Do NOT use the lighting field in theSoVolumeRendering
node. This field enables a CPU lighting computation that is slow.)- Gradient lighting
Thelighting
field enables gradient based lighting, where the "normal vector" at each sample along the ray is a gradient vector computed from the data values in the volume. Gradient based lighting only supports a single light source and only the first light in the scene graph (typically the viewer's "headlight") is used. No other lights affect the volume in this case. ThegradientQuality
field controls the algorithm used to compute gradient vectors. Several other fields affect the gradient computation includinggradientThreshold
,surfaceScalarExponent
andunnormalizedGradientExponent
. Setting surfaceScalarExponent to a small value, for example 2.0, is recommended.
- Deferred lighting
ThedeferredLighting
field enables screen space lighting, where the "normal vector" is computed from the final image depth buffer. Deferred lighting is faster and supports multiple light sources, but works best when the transfer function makes each data value either opaque or transparent. Deferred lighting is not affected by gradient related fields.
Unlike other primitives (including other VolumeViz primitives), volume lighting is not affected by an
SoLightModel
node. Also unlike other primitives, if lighting is enabled and there are no light nodes in the scene graph, the voxel color is taken from the transfer function or custom shader function "as is" (other primitives would be black in this case).Each light node's direction and intensity fields are used, but the color field is not currently used. The current
SoMaterial
specifies the ambient, specular, diffuse, and emissive color values for the lighting equation. Note that the default diffuse color is "light gray" (0.8), not full white. This allows specular lighting to push the color toward full white (as expected). If specular lighting is not desired, then changing this to full white (1.0) is recommended in order to see the true colors specified in the transfer function.The following figures show the same volume data:
Default volume rendering Pre-integrated volume rendering Lighted pre-integrated volume rendering Quality enhancement parameters Jittering: When
jittering
is set to true, a random offset is added to texture coordinates in order to decrease "ring" artifacts without the cost of drawing a higher number of slices. Note that this creates a "noisy" image. Instead we recommend setting theSoVolumeRender.samplingAlignment
field to BOUNDARY_ALIGNED.No Jittering With Jittering Gradient quality: When gradient lighting (
lighting
field) is enabled, thegradientQuality
field allows you to choose between various gradient computation techniques. The computational cost increases with the quality. Has no effect on deferred lighting.Low quality Medium quality High quality Surface scalar: When gradient lighting (
lighting
field) is enabled oredgeDetect2DMethod
is GRADIENT, thesurfaceScalarExponent
field disables lighting (or edge detection) on uniform surfaces in order to avoid noise in these area. This field should not be mixed withunnormalizedGradientExponent
. The default value is zero, but a small value, for example 2.0, is recommended. Has no effect on deferred lighting.Surface Scalar disabled Surface Scalar enabled Unnormalized gradient : When gradient lighting (
lighting
field) is enabled, ifunnormalizedGradientExponent
is not 0, voxels with small gradients will get more contribution from the ambient light than voxels with high gradients. It is similar tosurfaceScalarExponent
but uses the ambient light instead of the transfer function color for uniform surfaces. Has no effect on deferred lighting.Gradient threshold: When gradient lighting is enabled, gradients with a length less than
gradientThreshold
are ignored during the lighting computation. This avoids doing lighting on noise while still lighting important data. In the following screenshots, setting a threshold of 0.1 removed lighting on the noise surrounding the spheres. Has no effect on deferred lighting.With gradientThreshold
set to 0With gradientThreshold
set to 0.1Image enhancement parameters Various image enhancement techniques are available in this node and in
SoTransferFunction
.- Ambient occlusion
TheambientOcclusion
field enables a rendering technique that simulates self-shadowing of the volume. In other words, the amount of ambient (global) light in the scene reaching each sample is reduced by neighboring voxels. This effect makes it much easier to see the relative depth of features in the volume. Generally we recommend using this effect rather than the following effects.
Both lighting and/or shadow casting may also be enabled, but neither is required to use ambient occlusion. This effect works best when the volume data contains surfaces (region boundaries with relatively sharp gradients) or in voxelized rendering mode. In both cases it works best when voxels are either transparent or nearly opaque. If you use ambientOcclusion, you should set theSoVolumeRender.samplingAlignment
field to BOUNDARY_ALIGNED to reduce "slicing" artifacts.
- Boundary opacity
boundaryOpacity
increases opacity depending on the length of the gradient vector. Areas with large gradient changes will have their opacity increased according to theboundaryOpacityIntensity
. Note that this option has a significant performance penalty.
- Edge coloring
WhenedgeColoring
is on, the color of each voxel may be mixed with theedgeColor
. Areas where the normal (computed from the gradient) is facing the camera will have an unmodified color, whereas areas where the normal is more perpendicular to the view direction will tend towardsedgeColor
.
- Edge detection
WhenedgeDetect2D
is enabled, an image space filter is applied on the volume rendering image in order to detect edges, which will be highlighted. The results are affected by theedgeDetect2DInnerThreshold
andedgeDetect2DOuterThreshold
fields. TheedgeDetect2DMethod
bitmask allows to apply the edge detection on the image's luminance, depth and/or gradient. The gradient method may give noisy result, thesurfaceScalarExponent
may help to improve the result in this case. The gradient method has a significant performance penalty.
The following table shows the available edge detection techniques (explanation of faux shading is in
SoTransferFunction
):No Edges Boundary Opacity Edge 2D Edge Coloring Faux Shading (see SoTransferFunction
)Because this node is derived from
SoVolumeShader
, IVVR_FIRST_RESERVED_TEXTURE_UNIT applies to it. SeeSoVolumeShader
for more information.Volume projection Volume projection (
SoProjection
or derived classes) is incompatible with some options enabled by this node.
Do not enable the preIntegrated, jittering or edgeDetect2D fields when using projection.File format/default:
VolumeRenderingQuality {
lighting false preIntegrated true jittering false gradientThreshold 0.0001 edgeColoring false edgeColor (0, 0, 0) edgeThreshold 0.2 boundaryOpacity false boundaryOpacityIntensity 1.5 boundaryOpacityThreshold 1.5 edgeDetect2D false edgeDetect2DInnerThreshold 0.1 edgeDetect2DOuterThreshold 0.1 edgeDetect2DMethod LUMINANCE gradientQuality MEDIUM colorInterpolation true unnormalizedGradientExponent 0 surfaceScalarExponent 5 segmentedInterpolation false segmentedInterpolationThreshold 0.5 voxelizedRendering false voxelOutline false voxelOutlineThreshold 2. voxelOutlineWidth 2. voxelOutlineColor (0, 0, 0) ambientOcclusion false deferredLighting true interpolateOnMove true Action behavior:
SoGLRenderAction
Sets volume rendering quality parameters in the traversal state.- See Also:
SoVolumeRender
,SoVolumeShader
,SoVolumeIsosurface
,SoTransferFunction
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Nested Class Summary
Nested Classes Modifier and Type Class Description static class
SoVolumeRenderingQuality.EdgeDetect2DMethods
The edge detection algorithm used whenedgeDetect2D
is true, can work on the image luminance, depth buffer and/or gradient.static class
SoVolumeRenderingQuality.GradientQualities
Gradient Quality mode.static class
SoVolumeRenderingQuality.LightingModels
Deprecated.As of Open Inventor 10000.-
Nested classes/interfaces inherited from class com.openinventor.volumeviz.nodes.SoVolumeShader
SoVolumeShader.ShaderPositions
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Nested classes/interfaces inherited from class com.openinventor.inventor.nodes.SoShaderProgram
SoShaderProgram.GeometryInputTypes, SoShaderProgram.GeometryOutputTypes
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Nested classes/interfaces inherited from class com.openinventor.inventor.nodes.SoNode
SoNode.RenderModes
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Nested classes/interfaces inherited from class com.openinventor.inventor.Inventor
Inventor.ConstructorCommand
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Field Summary
Fields Modifier and Type Field Description SoSFBool
ambientOcclusion
If true, apply an ambient occlusion effect (default is false).SoSFBool
boundaryOpacity
Enable boundary opacity.SoSFFloat
boundaryOpacityIntensity
Applies whenboundaryOpacity
is true.SoSFFloat
boundaryOpacityThreshold
Applies whenboundaryOpacity
is true.SoSFBool
colorInterpolation
Controls interpolation of data values used for color lookup.SoSFBool
cubicInterpolation
Deprecated.As of Open Inventor 9300.SoSFBool
deferredLighting
Enable screen space lighting (computed on the GPU).SoSFColor
edgeColor
Color used to draw edges whenedgeColoring
oredgeDetect2D
is true.SoSFBool
edgeColoring
Enable edge coloring.SoSFBool
edgeDetect2D
Enable 2D edge detection.SoSFFloat
edgeDetect2DInnerThreshold
Increase this value to decrease noise on silhouette edges.SoSFBitMask<SoVolumeRenderingQuality.EdgeDetect2DMethods>
edgeDetect2DMethod
Method used for 2D edge detection.SoSFFloat
edgeDetect2DOuterThreshold
Increase this value to decrease noise on edges in the volume.SoSFFloat
edgeThreshold
If this value is low, more edges will be detected.SoSFEnum<SoVolumeRenderingQuality.GradientQualities>
gradientQuality
Specifies the algorithm used to compute gradients, for example, normals for lighting.SoSFFloat
gradientThreshold
Ignore all gradients with a magnitude less than the specified threshold.SoSFBool
jittering
Enable jittering.SoSFBool
lighting
Enable gradient based lighting (computed on the GPU).SoSFEnum<SoVolumeRenderingQuality.LightingModels>
lightingModel
Deprecated.As of Open Inventor 10000.SoSFBool
preIntegrated
Enable pre-integrated volume rendering.SoSFBool
segmentedInterpolation
Allow correct interpolation when rendering segmented data.SoSFFloat
segmentedInterpolationThreshold
Defines the iso distance used whensegmentedInterpolation
is true.SoSFFloat
surfaceScalarExponent
If this field is greater than or equal to 1, a surface with a small gradient will be less lighted than a surface with a high gradient.SoSFFloat
unnormalizedGradientExponent
When unnormalizedGradientExponent is not 0, surfaces with high gradients will be more lighted than surfaces with small gradients.SoSFBool
voxelizedRendering
If true,SoVolumeRender
displays voxels as individual cubes.SoSFBool
voxelOutline
If true, draw the outline of voxels (default is false).SoSFColor
voxelOutlineColor
WhenvoxelOutline
is true, this value specifies the voxel outline color.SoSFFloat
voxelOutlineThreshold
WhenvoxelOutline
is true, this threshold specifies the minimum size of a voxel, in screen pixels, for the voxel outline to be visible.SoSFFloat
voxelOutlineWidth
WhenvoxelOutline
is true, this value specifies the voxel outline width in pixels.-
Fields inherited from class com.openinventor.volumeviz.nodes.SoVolumeShader
forVolumeOnly, interpolateOnMove
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Fields inherited from class com.openinventor.inventor.nodes.SoShaderProgram
bufferObjects, generateTransparency, geometryInputType, geometryOutputType, images, maxGeometryOutputVertices, patchLength, shaderObject, shadowShader, vertexProgramTwoSide
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Fields inherited from class com.openinventor.inventor.Inventor
VERBOSE_LEVEL, ZeroHandle
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Constructor Summary
Constructors Constructor Description SoVolumeRenderingQuality()
Constructor.
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Method Summary
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Methods inherited from class com.openinventor.volumeviz.nodes.SoVolumeShader
isSupported, isSupported
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Methods inherited from class com.openinventor.inventor.nodes.SoShaderProgram
addShaderParameterImage, getFragmentShader, getGeometryShader, getNumReservedTextures, getTessellationControlShader, getTessellationEvaluationShader, getVertexShader, setComputeShader, setComputeShader, setFragmentShader, setFragmentShader, setGeometryShader, setGeometryShader, setTessellationControlShader, setTessellationControlShader, setTessellationEvaluationShader, setTessellationEvaluationShader, setVertexShader, setVertexShader
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Methods inherited from class com.openinventor.inventor.nodes.SoNode
affectsState, callback, copy, copy, distribute, doAction, getAlternateRep, getBoundingBox, getByName, getMatrix, getPrimitiveCount, getRenderEngineMode, getRenderUnitID, GLRender, GLRenderBelowPath, GLRenderInPath, GLRenderOffPath, grabEventsCleanup, grabEventsSetup, handleEvent, isBoundingBoxIgnoring, isOverride, pick, rayPick, search, setOverride, touch, write
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Methods inherited from class com.openinventor.inventor.fields.SoFieldContainer
copyFieldValues, copyFieldValues, enableNotify, fieldsAreEqual, get, getAllFields, getEventIn, getEventOut, getField, getFieldName, hasDefaultValues, isNotifyEnabled, set, setToDefaults
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Methods inherited from class com.openinventor.inventor.misc.SoBase
dispose, getName, isDisposable, isSynchronizable, setName, setSynchronizable
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Methods inherited from class com.openinventor.inventor.Inventor
getNativeResourceHandle
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Field Detail
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lighting
public final SoSFBool lighting
Enable gradient based lighting (computed on the GPU). Default is false. Gradient based lighting is computed using the direction and magnitude of gradient vectors computed from the data values in place of "normal vectors" in the lighting equation. A gradient vector is computed for each sample point along the rays cast through the volume.VolumeViz also supports screen space lighting (see the
deferredLighting
field).Notes:
- The result of the gradient lighting computation is affected by how the gradient vectors are computed. See the
gradientQuality
field. - Gradient lighting may produce "noisy" results when the gradient magnitudes are small and/or the gradient directions are not consistent. This often happens, for example, in relatively homogeneous regions of a volume. Several fields are provided to compensate for this effect. See
gradientThreshold
andsurfaceScalarExponent
. - Both gradient lighting and deferred lighting may be enabled at the same time, but the intent is that the application should use one or the other.
- In any case, do not use the
SoVolumeRender.lighting
field.
LIMITATIONS
- Only directional lights (
SoDirectionalLight
) are supported. - Only one light source, the first one traversed in the scene graph, is supported.
- The result of the gradient lighting computation is affected by how the gradient vectors are computed. See the
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preIntegrated
public final SoSFBool preIntegrated
Enable pre-integrated volume rendering.
Pre-integrated rendering can significantly increase image quality (at the cost of slightly lower performance). Default is true.Limitations:
- Pre-integration integrates between color map values. For typical scalar data containing sampled values, this provides a beneficial smoothing. When the color changes sharply between adjacent voxels, it can can cause values that are not actually in the original data to be displayed. This is undesireable for some data, for example "label" volumes resulting from segmentation. Pre-integration is not recommended for such data.
- The
preIntegrated
field has no effect onSoVolumeIsosurface
rendering. - The
preIntegrated
field is only considered when SoVolumeRendering.renderMode is set to VOLUME_RENDERING (the default).
-
jittering
public final SoSFBool jittering
Enable jittering.
If set to true, a random offset is added to texture coordinates in order to decrease ringing artifacts (boundary edge artifacts) without the cost of drawing a higher number of slices. Note that this creates a "noisy" image. Instead we recommend setting theSoVolumeRender.samplingAlignment
field to BOUNDARY_ALIGNED. Note: Jittering is only available when pre-integrated rendering is enabled. Default is false.
- Since:
- Open Inventor 7.0
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gradientThreshold
public final SoSFFloat gradientThreshold
Ignore all gradients with a magnitude less than the specified threshold.
Default is 0.0001, meaning that all gradients are used in the lighting computation. Maximum useful value is 1.0, because gradient vectors are normalized. Only affects gradient based lighting (lighting
field).
- Since:
- Open Inventor 7.0
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edgeColoring
public final SoSFBool edgeColoring
Enable edge coloring.
If true, changes the color based on the gradient direction (normal). Edges will be highlighted with the color specified inedgeColor
. Areas where the normal (computed from the gradient) is facing the camera will have an unmodified color, whereas areas where the normal is more perpendicular to the view direction will tend towardsedgeColor
. Default is false.
- Since:
- Open Inventor 7.0
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edgeColor
public final SoSFColor edgeColor
- Since:
- Open Inventor 7.0
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edgeThreshold
public final SoSFFloat edgeThreshold
If this value is low, more edges will be detected. Default is 0.2. Min value is 0. There is no max, but most of the time a value between 0 and 1 is good.
- Since:
- Open Inventor 7.0
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boundaryOpacity
public final SoSFBool boundaryOpacity
Enable boundary opacity.
If true, increases boundary opacity based on the gradient magnitude. Default is false.This effect has a significant performance penalty.
SoVolumeRender.subdivideTile
will be disabled if set to true.
- Since:
- Open Inventor 7.0
-
boundaryOpacityIntensity
public final SoSFFloat boundaryOpacityIntensity
Applies whenboundaryOpacity
is true. If > 1, this increases the boundary opacity globally. If < 1, decreases it. Default is 1.5.
- Since:
- Open Inventor 7.0
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boundaryOpacityThreshold
public final SoSFFloat boundaryOpacityThreshold
Applies whenboundaryOpacity
is true. If this value is low (near 0), only regions with a high gradient will be enhanced. Default is 1.5.
- Since:
- Open Inventor 7.0
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edgeDetect2D
public final SoSFBool edgeDetect2D
Enable 2D edge detection.
If this field is true, a 2D edge detection algorithm is used to highlight edges in the rendered image of the volume. Default is false.
- Since:
- Open Inventor 7.0
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edgeDetect2DInnerThreshold
public final SoSFFloat edgeDetect2DInnerThreshold
Increase this value to decrease noise on silhouette edges. 1 = remove all edges, 0 = remove nothing. Default is 0.1
- Since:
- Open Inventor 7.0
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edgeDetect2DOuterThreshold
public final SoSFFloat edgeDetect2DOuterThreshold
Increase this value to decrease noise on edges in the volume. 1 = remove all edges, 0 = remove nothing. Default is 0.1
- Since:
- Open Inventor 7.0
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edgeDetect2DMethod
public final SoSFBitMask<SoVolumeRenderingQuality.EdgeDetect2DMethods> edgeDetect2DMethod
Method used for 2D edge detection.
Specifies the edge detection algorithm used whenedgeDetect2D
is true. Edge detection can work on the image luminance, depth buffer and/or gradient. For example, gradients may be too noisy to give interesting edges and may be ignored with this field. The gradient method is also the slowest (luminance being the fastest) because it needs more texture fetchs. SeeEdgeDetect2DMethod
. Default is LUMINANCE and GRADIENT.
- Since:
- Open Inventor 8.1
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gradientQuality
public final SoSFEnum<SoVolumeRenderingQuality.GradientQualities> gradientQuality
Specifies the algorithm used to compute gradients, for example, normals for lighting. Only affects gradient based lighting (lighting
field).. Default is MEDIUM.
- Since:
- Open Inventor 7.0
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colorInterpolation
public final SoSFBool colorInterpolation
Controls interpolation of data values used for color lookup.
If false, interpolation is not done on data values used to access the colormap but is still done when computing gradient for lighting. This may be used to render a segmented dataset where interpolation is not appropriate. Default is true. Only affects gradient based lighting (lighting
field).Generally it's better to set the
SoVolumeRender.interpolation
field to NEAREST, unless you really want to use gradient based lighting.- Since:
- Open Inventor 7.2
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surfaceScalarExponent
public final SoSFFloat surfaceScalarExponent
If this field is greater than or equal to 1, a surface with a small gradient will be less lighted than a surface with a high gradient. The resulting color is a mix between the lighted voxel color and the non-lighted voxel color (ie: the corresponding entry in the colormap). If the value is less than 1, the field is ignored. Values higher than 256 will apply lighting on almost all surfaces. For most datasets, values between 2 and 16 should be enough. Default is 5.
Only affects gradient based lighting (lighting
field).- Since:
- Open Inventor 8.1
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unnormalizedGradientExponent
public final SoSFFloat unnormalizedGradientExponent
When unnormalizedGradientExponent is not 0, surfaces with high gradients will be more lighted than surfaces with small gradients. Voxels with small gradients will have less diffuse and specular than other with high gradients (ie: ambient color will be the biggest contributor). This lighting contribution can be controlled with this field. If this value is high, smaller gradients will contribute to lighting. Values higher than 256 will apply lighting on almost all surfaces. For most dataset, values between 2 and 16 should be enough. Default is 0.
Only affects gradient based lighting (lighting
field).- Since:
- Open Inventor 8.1
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segmentedInterpolation
public final SoSFBool segmentedInterpolation
Allow correct interpolation when rendering segmented data. NOTE: Only available onSoVolumeIsosurface
.
- Since:
- Open Inventor 8.5
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segmentedInterpolationThreshold
public final SoSFFloat segmentedInterpolationThreshold
Defines the iso distance used whensegmentedInterpolation
is true.
Default is 0.5. value must be in the range [0 .. 1] NOTE: Only available onSoVolumeIsosurface
.
- Since:
- Open Inventor 8.6
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voxelizedRendering
public final SoSFBool voxelizedRendering
If true,SoVolumeRender
displays voxels as individual cubes. Default is false.Limitations:
- When using multiple independent volumes (different dimensions or extents) inside a
SoMultiDataSeparator
, this feature is not supported. Only the last volume in the scenegraph will be displayed.
- Since:
- Open Inventor 9.0
- When using multiple independent volumes (different dimensions or extents) inside a
-
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voxelOutline
public final SoSFBool voxelOutline
If true, draw the outline of voxels (default is false). Notes:- Since Open Inventor 9.6, this mode applies to volume slice primitives (
SoOrthoSlice
etc) in addition to volume rendering. - In the case of
SoObliqueSlice
, you may see triangles, quadrilaterals and even irregular pentagons in some cases. These lines are correct and correspond to the intersections between the voxels and the oblique slice. For example:
- Since:
- Open Inventor 9.0
- Since Open Inventor 9.6, this mode applies to volume slice primitives (
-
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voxelOutlineThreshold
public final SoSFFloat voxelOutlineThreshold
WhenvoxelOutline
is true, this threshold specifies the minimum size of a voxel, in screen pixels, for the voxel outline to be visible. Default is 2, meaning that outline is visible only if a single voxel is bigger than 2 screen pixels.- Since:
- Open Inventor 9.2
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voxelOutlineWidth
public final SoSFFloat voxelOutlineWidth
WhenvoxelOutline
is true, this value specifies the voxel outline width in pixels. Default is 2 pixels.- Since:
- Open Inventor 9.6
-
voxelOutlineColor
public final SoSFColor voxelOutlineColor
WhenvoxelOutline
is true, this value specifies the voxel outline color. Default is black : (0, 0, 0).- Since:
- Open Inventor 9.6
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ambientOcclusion
public final SoSFBool ambientOcclusion
If true, apply an ambient occlusion effect (default is false). Ambient occlusion is an shading effect that approximates attenuation of light due to neighboring voxels. It works best when the volume data contains surfaces (region boundaries with relatively sharp gradients), or in voxelized rendering mode, and those voxels are opaque.If you use ambientOcclusion, you should set the
SoVolumeRender.samplingAlignment
field to BOUNDARY_ALIGNED to reduce "slicing" artifacts.Notes:
- This effect is only applied on voxels that are considered to be "solid" (non-transparent).
The "solid" transparency threshold is controlled by the value ofSoVolumeRender.opacityThreshold
.
- Since:
- Open Inventor 9.1
- This effect is only applied on voxels that are considered to be "solid" (non-transparent).
-
deferredLighting
public final SoSFBool deferredLighting
Enable screen space lighting (computed on the GPU). Default is true. Deferred lighting is computed based on the final image depth buffer instead using the data gradients. It is much faster than gradient based lighting (see thelighting
field) and supports multiple light sources (up to 8). Because it is not based on data gradients, it does not have problems with small/random gradients and it gives a much better result when using clipping nodes likeSoVolumeClippingGroup
orSoUniformGridClipping
. Light sources are defined by Open InventorSoDirectionalLight
nodes.Notes:
- Since Open Inventor 9.3, deferred lighting supports up to 8 light sources.
- Both deferred lighting and gradient lighting may be enabled at the same time, but the intent is that the application should use one or the other.
- Gradient related fields, e.g. surfaceScalarExponent, have no effect on deferred lighting.
- In any case, do not use the
SoVolumeRender.lighting
field. - The lighting model used by deferred lighting is the Phong reflection model. Its parameters are defined by the current
SoMaterial
on state. - This effect is only applied on voxels that are considered to be "solid" (non-transparent).
The "solid" transparency threshold is controlled by the value ofSoVolumeRender.opacityThreshold
.
LIMITATIONS
- Only directional lights (
SoDirectionalLight
) are supported. - If you use deferredLighting, you should set the
SoVolumeRender.samplingAlignment
field to BOUNDARY_ALIGNED or SMOOTH_BOUNDARY_ALIGNED to reduce "slicing" artifacts. - The light color is taken into account, but not the light intensity field. You can get the same effect as reduced intensity by reducing the light color values.
- Deferred lighting works best when
- The volume data can be considered to contain "surfaces", for example bones (etc) in medical data or metal parts in NDT data, and
- The transfer function makes the surface material relatively opaque and the surrounding material relatively transparent.
- Since:
- Open Inventor 9.2
-
cubicInterpolation
@Deprecated public final SoSFBool cubicInterpolation
Deprecated.As of Open Inventor 9300. Use SoVolumeShape.interpolation field instead.Enable cubic interpolation of data values.
Warning Heavy GPU usage. Primarily useful for still image rendering. Default is false.
- Since:
- Open Inventor 7.0
Warning Deprecated since Open Inventor 9300. Use
SoVolumeShape.interpolation
field instead.
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lightingModel
@Deprecated public final SoSFEnum<SoVolumeRenderingQuality.LightingModels> lightingModel
Deprecated.As of Open Inventor 10000. No longer used. OPENGL mode is always used.Sets the lighting model. For backward compatibility with Open Inventor v6. Applications should set this field to OPENGL. Only affects gradient based lighting (lighting
field).. Default is OIV6.
- Since:
- Open Inventor 7.0
Warning Deprecated since Open Inventor 10000. No longer used. OPENGL mode is always used.