SoLightModel Class |
Node that defines the lighting model to use when rendering.
Namespace: OIV.Inventor.Nodes
The SoLightModel type exposes the following members.
Name | Description | |
---|---|---|
SoLightModel | Creates a light model node with default settings. |
Name | Description | |
---|---|---|
AffectsState | Returns true if a node has an effect on the state during traversal. | |
Callback | (Overrides SoNodeCallback(SoCallbackAction).) | |
Copy | Calls Copy(false). (Inherited from SoNode.) | |
Copy(Boolean) | Creates and returns an exact copy of the node. | |
CopyFieldValues(SoFieldContainer) | Calls CopyFieldValues(fc, false). (Inherited from SoFieldContainer.) | |
CopyFieldValues(SoFieldContainer, Boolean) | Copies the contents of fc's fields into this object's fields. | |
Dispose |
Releases all resources used by SoDisposable.
(Inherited from SoDisposable.) | |
Distribute | (Inherited from SoNode.) | |
DoAction | (Overrides SoNodeDoAction(SoAction).) | |
EnableNotify | Notification at this Field Container is enabled (if flag == true) or disabled (if flag == false). | |
Equals | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) | |
FieldsAreEqual | Returns true if this object's fields are exactly equal to fc's fields. | |
Get | Returns the values of the fields of this object in the Open Inventor ASCII file format in the given string. | |
GetAllFields | Returns a list of fields, including the eventIn's and eventOut's. | |
GetAlternateRep | This method is called by actions to allow the node to provide an "alternate representation" when appropriate (typically depending on the action type). | |
GetBoundingBox | (Inherited from SoNode.) | |
GetEventIn | Returns a the eventIn with the given name. | |
GetEventOut | Returns the eventOut with the given name. | |
GetField | Returns a the field of this object whose name is fieldName. | |
GetFieldName | Returns the name of the given field in the fieldName argument. | |
GetFields | Appends references to all of this object's fields to resultList, and returns the number of fields appended. | |
GetHashCode |
Overrides GetHashCode().
(Inherited from SoNetBase.) | |
GetMatrix | (Inherited from SoNode.) | |
GetName | Returns the name of an instance. | |
GetPrimitiveCount | (Inherited from SoNode.) | |
GetRenderEngineMode | Returns the supported Render engine mode. | |
GetRenderUnitID | (Inherited from SoNode.) | |
GetStringName | (Inherited from SoBase.) | |
GetType | Gets the Type of the current instance. (Inherited from Object.) | |
GLRender | (Overrides SoNodeGLRender(SoGLRenderAction).) | |
GLRenderBelowPath | (Inherited from SoNode.) | |
GLRenderInPath | (Inherited from SoNode.) | |
GLRenderOffPath | (Inherited from SoNode.) | |
GrabEventsCleanup | (Inherited from SoNode.) | |
GrabEventsSetup | (Inherited from SoNode.) | |
HandleEvent | (Inherited from SoNode.) | |
HasDefaultValues | Returns true if all of the object's fields have their default values. | |
IsBoundingBoxIgnoring | This method is used by getBoundingBox action traversal to know if the current node must be traversed or not, ie the bounding should be ignored. | |
IsNotifyEnabled | Notification is the process of telling interested objects that this object has changed. | |
IsOverride | Returns the state of the override field. | |
IsSynchronizable | Gets the ScaleViz synchronizable state of this object. | |
Pick | (Inherited from SoNode.) | |
RayPick | (Inherited from SoNode.) | |
Search | (Inherited from SoNode.) | |
Set | Sets one or more fields in this object to the values specified in the given string, which should be a string in the Open Inventor file format. | |
SetName | (Inherited from SoBase.) | |
SetOverride | Set the state of the override field. | |
SetSynchronizable | Sets this to be a ScaleViz synchronizable object. | |
SetToDefaults | Sets all fields in this object to their default values. | |
ToString |
Converts this SoBase structure to a human readable string.
(Inherited from SoBase.) | |
Touch | Marks an instance as modified, simulating a change to it. | |
Write | (Inherited from SoNode.) |
Name | Description | |
---|---|---|
IsDisposable | ISafeDisposable interface implementation.
(Inherited from SoDisposable.) | |
model | Lighting model to use . | |
UserData |
Gets or sets the user data to be contained by the field container.
(Inherited from SoFieldContainer.) |
This node defines the lighting model to be used when rendering subsequent shapes. The lighting model is specified in the OIV.Inventor.Nodes.SoLightModel.model field which is PER_VERTEX_PHONG by default.
Several types of light model are supported and the following images are examples of rendering of the same scene using a different light model.
OIV.Inventor.Nodes.SoLightModel.Models.BASE_COLOR | OIV.Inventor.Nodes.SoLightModel.Models.PER_PIXEL_PHONG | OIV.Inventor.Nodes.SoLightModel.Models.PHYSICALLY_BASED |
When the light model is not OIV.Inventor.Nodes.SoLightModel.Models.BASE_COLOR, there must be light nodes (e.g. OIV.Inventor.Nodes.SoDirectionalLight) in the scene graph for objects to be easily visible. When using the Open Inventor viewer classes (e.g. OIV.Inventor.Win.Viewers.SoWinExaminerViewer), the viewer will create a "headlight" (directional light attached to the camera) if no other light nodes exist when setSceneGraph() is called. When using the Open Inventor viewer components (e.g. SceneExaminer), a "headlight" is automatically added to the scene graph.
An OIV.Inventor.Nodes.SoEnvironment node can be used to specify additional options related to lighting:
The ambient light component of the Phong reflection model.
Light attenuation for OIV.Inventor.Nodes.SoPointLight and OIV.Inventor.Nodes.SoSpotLight nodes.
Ambient occlusion.
# Definition of base color
All the light models supported by Open Inventor use the concept of base color composed by 3 channels red green blue (rgb). It corresponds to the color of an object before being altered by light effects. Unfortunatly the term of *base color* is not always used in the API and documentation, sometimes it can be a mentionned as *diffuse color*, sometimes it can be a *rgb color*, a *rgb* or just a *color*.
The following fields define the same concept of *base color* of an object:
Thus, the following code C++ samples are equivalent and define a single red opaque base color:
mySoMaterial->diffuseColor = SbColor(1,0,0); mySoMaterial->transparency = 0 ; mySoPhysicalMaterial->baseColor = SbColorRGBA(1,0,0,1); mySoBaseColor->rgb = SbColor(1,0,0); mySoPackedColor->orderedRGBA = SbColorRGBA(1,0,0,1).getPackedValue(); mySoColorMap->colorMap.setValues(0, 4, new float[4]{ 1, 0, 0, 1 }); mySoBufferedShape->colorBuffer = new SoCpuBufferObject(new float[4]{ 1, 0, 0, 1 }, 4 * sizeof(float)); mySoVertexProperty->orderedRGBA = SbColorRGBA(1,0,0,1).getPackedValue();
Moreover, changing the value of any of those fields override the *base color* of an object. It means that if 2 different fields are set to specify a color, the current definition of a color during the scene graph traversal overrides the previous one. For instance, the following code sample specifies an opaque red color that overrides the semi opaque green
mySoPhysicalMaterial.baseColor.SetValue(new SbColorRGBA(0,1,0,0.5f)); // semi opaque green color mySoMaterial.diffuseColor.SetValue(new SbColor(1,0,0)); // red color mySoMaterial.transparency.SetValue(0); myRoot.addChild(mySoPhysicalMaterial); myRoot.addChild(mySoMaterial); // this red material overrides the green color
# Light model and property nodes
According to the light model selected, the following notes explain what is taken into account in the scene graph, and what is ignored:
Using model OIV.Inventor.Nodes.SoLightModel.Models.BASE_COLOR
Objects are drawn using the base color only. There is no lighting
if a node related to the material is visited after the OIV.Inventor.Nodes.SoBaseColor during the traversal, the rgb defined by the OIV.Inventor.Nodes.SoBaseColor may change
The base color is specified as described [above](OIV.Inventor.Nodes.SoLightModel-base-color-def)
The OIV.Inventor.Nodes.SoMaterial fields are ignored except diffuseColor and transparency
The OIV.Inventor.Nodes.SoPhysicalMaterial fields are ignored except baseColor
The OIV.Inventor.Nodes.SoLight instances are ignored
The OIV.Inventor.Nodes.SoEnvironment instances are ignored
Using OIV.Inventor.Nodes.SoLightModel.Models.PER_VERTEX_PHONG or OIV.Inventor.Nodes.SoLightModel.Models.PER_PIXEL_PHONG
The lighting takes into account all fields of OIV.Inventor.Nodes.SoMaterial
if a node related to the material is visited after the OIV.Inventor.Nodes.SoMaterial during the traversal, the diffuseColor and transparency defined by the OIV.Inventor.Nodes.SoMaterial may change
The base color is specified as described [above](OIV.Inventor.Nodes.SoLightModel-base-color-def)
The OIV.Inventor.Nodes.SoPhysicalMaterial fields are ignored except baseColor
The OIV.Inventor.Nodes.SoLight instances are used
The OIV.Inventor.Nodes.SoEnvironment instances are used
Using OIV.Inventor.Nodes.SoLightModel.Models.PHYSICALLY_BASED
The lighting takes into account all fields of OIV.Inventor.Nodes.SoPhysicalMaterial
if a node related to the material is visited after the OIV.Inventor.Nodes.SoPhysicalMaterial during the traversal, the baseColor defined by the OIV.Inventor.Nodes.SoPhysicalMaterial may change
The base color is specified as described [above](OIV.Inventor.Nodes.SoLightModel-base-color-def)
The OIV.Inventor.Nodes.SoMaterial fields are ignored except diffuseColor and transparency
The OIV.Inventor.Nodes.SoLight instances are used
The OIV.Inventor.Nodes.SoEnvironment instances are used
# Two side lighting
By default, lighting is only computed for the "front" faces of geometry, so the back face of the geometry will be dark. The front face is determined by the normal vector, if specified, or by the vertex ordering (see OIV.Inventor.Nodes.SoShapeHints) if normals are computed by Open Inventor. To enable "two sided" lighting (lighting both front and back faces) see OIV.Inventor.Nodes.SoShapeHints.
# Light model and VolumeViz
The OIV.Inventor.Nodes.SoLightModel node controls lighting for most VolumeViz shapes, but *not* for OIV.VolumeViz.Nodes.SoVolumeRender. The lighting for volume rendering is controlled by the OIV.VolumeViz.Nodes.SoVolumeRenderingQuality node.
Two sided lighting is automatically enabled for "slice" shapes, such as OIV.VolumeViz.Nodes.SoOrthoSlice.
LightModel {
model | PER_PIXEL_PHONG |
OIV.Inventor.Actions.SoGLRenderAction, OIV.Inventor.Actions.SoCallbackAction Sets the current lighting model in the state.