SoMaterial Class Reference

Surface material definition node. More...

#include <Inventor/nodes/SoMaterial.h>

Inheritance diagram for SoMaterial:

Public Member Functions
virtual SoType	getTypeId () const
	Returns the type identifier for this specific instance.
	SoMaterial ()
	Creates a material node with default settings.
virtual void	setOverride (const SbBool state)
	Set the state of the override field.
virtual SbBool	isOverride () const
	Returns the state of the override field.
Public Member Functions inherited from SoNode
virtual SoNode *	copy (SbBool copyConnections=FALSE) const
	Creates and returns an exact copy of the node.
virtual SbBool	affectsState () const
	Returns TRUE if a node has an effect on the state during traversal.
virtual void	touch ()
	Marks an instance as modified, simulating a change to it.
Public Member Functions inherited from SoFieldContainer
void	setToDefaults ()
	Sets all fields in this object to their default values.
SbBool	hasDefaultValues () const
	Returns TRUE if all of the object's fields have their default values.
SbBool	fieldsAreEqual (const SoFieldContainer *fc) const
	Returns TRUE if this object's fields are exactly equal to fc's fields.
void	copyFieldValues (const SoFieldContainer *fc, SbBool copyConnections=FALSE)
	Copies the contents of fc's fields into this object's fields.
SoNONUNICODE SbBool	set (const char *fieldDataString)
	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.
SbBool	set (const SbString &fieldDataString)
	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.
void	get (SbString &fieldDataString)
	Returns the values of the fields of this object in the Open Inventor ASCII file format in the given string.
virtual int	getFields (SoFieldList &list) const
	Appends references to all of this object's fields to resultList, and returns the number of fields appended.
virtual int	getAllFields (SoFieldList &list) const
	Returns a list of fields, including the eventIn's and eventOut's.
virtual SoField *	getField (const SbName &fieldName) const
	Returns a the field of this object whose name is fieldName.
virtual SoField *	getEventIn (const SbName &fieldName) const
	Returns a the eventIn with the given name.
virtual SoField *	getEventOut (const SbName &fieldName) const
	Returns the eventOut with the given name.
SbBool	getFieldName (const SoField *field, SbName &fieldName) const
	Returns the name of the given field in the fieldName argument.
SbBool	enableNotify (SbBool flag)
	Notification at this Field Container is enabled (if flag == TRUE) or disabled (if flag == FALSE).
SbBool	isNotifyEnabled () const
	Notification is the process of telling interested objects that this object has changed.
virtual void	setUserData (void *data)
	Sets application data.
void *	getUserData (void) const
	Gets user application data.
Public Member Functions inherited from SoBase
virtual SbName	getName () const
	Returns the name of an instance.
virtual void	setName (const SbName &name)
	Sets the name of an instance.
void	setSynchronizable (const bool b)
	Sets this to be a ScaleViz synchronizable object.
bool	isSynchronizable () const
	Gets the ScaleViz synchronizable state of this object.
Public Member Functions inherited from SoRefCounter
void	ref () const
	Adds a reference to an instance.
void	unref () const
	Removes a reference from an instance.
void	unrefNoDelete () const
	unrefNoDelete() should be called when it is desired to decrement the reference count, but not delete the instance if this brings the reference count to zero.
int	getRefCount () const
	Returns current reference count.
void	lock () const
	lock this instance.
void	unlock () const
	unlock this instance.
Public Member Functions inherited from SoTypedObject
SbBool	isOfType (const SoType &type) const
	Returns TRUE if this object is of the type specified in type or is derived from that type.
template<typename TypedObjectClass >
SbBool	isOfType () const
	Returns TRUE if this object is of the type of class TypedObjectClass or is derived from that class.

Static Public Member Functions
static SoType	getClassTypeId ()
	Returns the type identifier for this class.
Static Public Member Functions inherited from SoNode
static SoType	getClassTypeId ()
	Returns the type identifier for this class.
static SoNode *	getByName (const SbName &name)
	A node's name can be set using SoBase::setName().
static int	getByName (const SbName &name, SoNodeList &list)
	A node's name can be set using SoBase::setName().
Static Public Member Functions inherited from SoFieldContainer
static SoType	getClassTypeId ()
	Returns the type of this class.
Static Public Member Functions inherited from SoBase
static SoType	getClassTypeId ()
	Returns type identifier for this class.
Static Public Member Functions inherited from SoTypedObject
static SoType	getClassTypeId ()
	Returns the type identifier for this class.

Public Attributes
SoMFColor	ambientColor
	Ambient color of the surface.
SoMFColor	diffuseColor
	Diffuse color(s) of the surface.
SoMFColor	specularColor
	Specular color of the surface.
SoMFColor	emissiveColor
	Emissive color of the surface.
SoMFFloat	shininess
	Shininess coefficient of the surface.
SoMFFloat	transparency
	Transparency value(s) of the surface.

Deprecated
class	SoIfWeeder
	DirectViz rendering only.
class	SoIfBuilder
	DirectViz rendering only.
class	SoIfShape
	DirectViz rendering only.
class	SoIfMerger
	DirectViz rendering only.

Detailed Description

Surface material definition node.

This node defines the current surface material properties for all subsequent shapes. SoMaterial sets several components of the current material during traversal. The ambientColor, diffuseColor, emissiveColor, specularColor and shininess fields are interpreted according to the classic OpenGL lighting model. The transparency field is effectively the inverse of "opacity" or "alpha value".

If lighting is turned off (SoLightModel set to BASE_COLOR), only the diffuse color and transparency fields are used to render geometry.

Multiple values can be specified for the diffuseColor and transparency fields. Different shapes interpret materials with multiple values differently. To bind materials to shapes, use an SoMaterialBinding node.

Several other nodes can be used to set diffuse color and transparency for geometry.

If the other color values are not needed, these nodes use a little less memory than an SoMaterial node, especially if multiple color values are specified. Generally SoVertexProperty is the most efficient mechanism and may provide better performance than using SoMaterial. Note that for these nodes transparency is set as "alpha value" (inverse of transparency).

• Diffuse color (only) can also be specified using an SoBaseColor node.
  
• Diffuse color and transparency can also be specified using an SoPackedColor node.
• Diffuse color and transparency can also be specified for polygonal geometry using the orderedRGBA field of SoVertexProperty.

Lighting and material RGB values:

The color components specified for lights mean something different than for materials. For a light, the numbers correspond to a percentage of full intensity for each color. If the R, G, and B values for a light's color are all 1.0, the light is the brightest possible white. If the values are 0.5, the color is still white, but only at half intensity, so it appears gray. If R=G=1 and B=0 (full red and green with no blue), the light appears yellow. The intensity can also be modulated using the SoLight::intensity field.

For materials, the numbers correspond to the reflected percentages of those colors. So if R=1, G=0.5, and B=0 for a material, that material reflects all the incoming red light, half the incoming green, and none of the incoming blue light. In other words, if an OpenGL light has components (LR, LG, LB), and a material has corresponding components (MR, MG, MB), then, ignoring all other reflectivity effects, the light that arrives at the eye is given by (LR*MR, LG*MG, LB*MB). As a result, for example, shining a pure blue light on a pure red cone has no visible effect.

Similarly, if you have two lights that send (R1, G1, B1) and (R2, G2, B2) to the eye, the components are added, giving (R1+R2, G1+G2, B1+B2). If any of the sums are greater than 1 (corresponding to a color brighter than the hardware can display), the component is clamped to 1.

Override material:

To force all geometry following/below this node to use specific color and transparency values, call the setOverride() method with true. Overriding the diffuse color and transparency overrides the color and transparency values in other nodes including SoPackedColor and SoVertexProperty. This can be useful, for example, to highlight a selected object.

It is also possible to override only a subset of the SoMaterial fields. If, for example, you only want to override the diffuse color, but not the other values, call setIgnored(true) on the fields that you do not want to override. But note that this selective override technique only works on other SoMaterial nodes! For SoPackedColor and SoVertexProperty, the diffuseColor and transparency values are bound together and cannot be overridden separately.

Transparency:

The default transparency algorithm is NO_SORT. To get a nice appearance for transparent objects you must change this to another value, for example, OPAQUE_FIRST or SORTED_PIXEL, using the setTransparencyType method in the Viewer class. See SoGLRenderAction for a discussion of transparency algorithms and rendering order.

VolumeViz shapes:

For scalar (non-RGBA) volumes, the color and alpha value of a voxel is affected by two nodes. SoMaterial's diffuseColor field specifies the "base" color and alpha values for all voxels. SoTransferFunction specifies color and alpha values based on the voxel value. The final voxel color and alpha (before lighting and other effects) is computed by multiplying these two color and alpha values. The default material is 0.8, 0.8, 0.8, 1 (fully opaque gray). The 0.8 value for R, G and B allows lighting to increase the brightness of the voxel. For slice rendering without lighting, the application may want to set the material to 1, 1, 1, 1 so that only the SoTransferFunction affects the voxel color and alpha. Effectively the material alpha value (aka transparency) is a "global" multiplier that can be used to increase or decrease the transparency of all voxels in the volume.

FILE FORMAT/DEFAULT

Material {

ambientColor	0.2 0.2 0.2
diffuseColor	0.8 0.8 0.8
specularColor	0 0 0
emissiveColor	0 0 0
shininess	0.2
transparency	0

}

ACTION BEHAVIOR

SoGLRenderAction, SoCallbackAction
Sets the ambient color, the diffuse color, the specular color, the emissive color, the shininess, and the transparency of the current material. Sets: SoMaterialElement

SEE ALSO

SoBaseColor, SoLightModel, SoMaterialBinding, SoPackedColor, SoVertexProperty,

Definition at line 186 of file SoMaterial.h.

Constructor & Destructor Documentation

SoMaterial()

SoMaterial::SoMaterial

(

)

Creates a material node with default settings.

Member Function Documentation

getClassTypeId()

static SoType SoMaterial::getClassTypeId ( )

static

Returns the type identifier for this class.

getTypeId()

virtual SoType SoMaterial::getTypeId ( ) const

virtual

Returns the type identifier for this specific instance.

Reimplemented from SoNode.

isOverride()

virtual SbBool SoMaterial::isOverride ( ) const

inlinevirtual

Returns the state of the override field.

Reimplemented from SoNode.

Definition at line 272 of file SoMaterial.h.

setOverride()

virtual void SoMaterial::setOverride ( const SbBool  state )

inlinevirtual

Set the state of the override field.

see SoNode::setOverride doc.

Reimplemented from SoNode.

Definition at line 266 of file SoMaterial.h.

Friends And Related Symbol Documentation

SoIfBuilder

friend class SoIfBuilder

friend

DirectViz rendering only.

Specifies that all the shapes using this material node will receive shadows from other shapes when rendering using DirectViz.

NOTE: field available since Open Inventor 6.1

Definition at line 317 of file SoMaterial.h.

SoIfMerger

friend class SoIfMerger

friend

DirectViz rendering only.

Specifies that all the shapes using this material node will receive shadows from other shapes when rendering using DirectViz.

NOTE: field available since Open Inventor 6.1

Definition at line 319 of file SoMaterial.h.

SoIfShape

friend class SoIfShape

friend

DirectViz rendering only.

Specifies that all the shapes using this material node will receive shadows from other shapes when rendering using DirectViz.

NOTE: field available since Open Inventor 6.1

Definition at line 318 of file SoMaterial.h.

SoIfWeeder

friend class SoIfWeeder

friend

DirectViz rendering only.

Specifies that all the shapes using this material node will receive shadows from other shapes when rendering using DirectViz.

NOTE: field available since Open Inventor 6.1

Definition at line 316 of file SoMaterial.h.

Member Data Documentation

ambientColor

SoMFColor SoMaterial::ambientColor

Ambient color of the surface.

Default is 0.2 0.2 0.2.

Ambient reflectance affects the overall color of the object. Because diffuse reflectance is brightest where an object is directly illuminated, ambient reflectance is most noticeable where an object receives no direct illumination. An object's total ambient reflectance is affected by the global ambient light (see SoEnvironment) and ambient light from individual light sources. Like diffuse reflectance, ambient reflectance is not affected by the position of the camera.

Definition at line 203 of file SoMaterial.h.

diffuseColor

SoMFColor SoMaterial::diffuseColor

Diffuse color(s) of the surface.

Default is 0.8 0.8 0.8.

Diffuse reflectance plays the most important role in determining the appearance of an object. It's affected by the color of the incident light(s) and the angle of each incident light relative to the object's normal direction. (It's most intense where the incident light falls perpendicular to the surface.) The position of the camera doesn't affect diffuse reflectance at all.

Definition at line 214 of file SoMaterial.h.

emissiveColor

SoMFColor SoMaterial::emissiveColor

Emissive color of the surface.

Default is 0 0 0.

Emissive color makes an object appear to be giving off light of that color, independent of any lights (or lack of lights) in the scene. It can be useful for highlighting selected objects in the scene.

Definition at line 237 of file SoMaterial.h.

shininess

SoMFFloat SoMaterial::shininess

Shininess coefficient of the surface.

Values can range from 0.0 to 1.0. Default is 0.2.

The dot product of the vector reflected by the surface normal and the inverted light vector is raised to the "Shininess" power. The higher the shininess number, the smaller the resulting specular highlight turns out to be.

Definition at line 247 of file SoMaterial.h.

specularColor

SoMFColor SoMaterial::specularColor

Specular color of the surface.

Default is 0 0 0.

Specular reflection from an object produces highlights. Unlike ambient and diffuse reflection, the amount of specular reflection does depend on the location of the camera - it's brightest along the direct angle of reflection. To see this, imagine looking at a metallic ball outdoors in the sunlight. As you move your head, the highlight created by the sunlight moves with you to some extent. However, if you move your head too much, you lose the highlight entirely.

This field specifies the color of the reflected light. The shininess field controls the size and brightness of the highlight.

Definition at line 228 of file SoMaterial.h.

transparency

SoMFFloat SoMaterial::transparency

Transparency value(s) of the surface.

Values can range from 0.0 for opaque surfaces to 1.0 for completely transparent surfaces. Default is 0 (opaque).

Transparency is the inverse of "opacity" or "alpha" value.

Definition at line 255 of file SoMaterial.h.

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The documentation for this class was generated from the following file:

• Inventor/nodes/SoMaterial.h