Provided by: libcoin60-doc_3.1.3-2_all bug

NAME

       SoMaterial -

       The SoMaterial class is a node type for setting up material values for scene geometry.

       After traversing an SoMaterial node, subsequent shape nodes with geometry in the scene
       graph will use values from the material 'pool' of the traversal state set up from nodes of
       this type.

SYNOPSIS

       #include <Inventor/nodes/SoMaterial.h>

       Inherits SoNode.

   Public Member Functions
       SoMaterial (void)
       virtual void doAction (SoAction *action)
       virtual void GLRender (SoGLRenderAction *action)
       virtual void callback (SoCallbackAction *action)

   Static Public Member Functions
       static void initClass (void)

   Public Attributes
       SoMFColor ambientColor
       SoMFColor diffuseColor
       SoMFColor specularColor
       SoMFColor emissiveColor
       SoMFFloat shininess
       SoMFFloat transparency

   Protected Member Functions
       virtual ~SoMaterial ()
       virtual void notify (SoNotList *list)

Detailed Description

       The SoMaterial class is a node type for setting up material values for scene geometry.

       After traversing an SoMaterial node, subsequent shape nodes with geometry in the scene
       graph will use values from the material 'pool' of the traversal state set up from nodes of
       this type.

       For detailed information on the various components, see the OpenGL color model, presented
       in the chapter 'Colors and Coloring' (chapter 2.13 in the OpenGL 1.4 specification).

       Note that values from a material node will replace the previous values from the traversal
       state, they will not accumulate. That's the case even when e.g. material changes are
       implicit in an iv-file, as illustrated by the following example:

       Also note that support for multiple values in ambientColor, emissiveColor, specularColor
       and shininess was obsoleted in Open Inventor 2.1. The reason for this design change was
       performance driven, since it's relatively slow to change the OpenGL material properties.
       Changing the diffuse color value is fast though, so it's still possible to have multiple
       diffuseColor and transparency values.

         #Inventor V2.1 ascii

         Material { ambientColor 1 0 0 }
         Cone { }

         Translation { translation 5 0 0 }

         Material { }
         Sphere { }
         .fi

       (The SoSphere will not 'inherit' the SoMaterial::ambientColor from the first SoMaterial node, even though it is not explicitly set in the second material node. The default value of SoMaterial::ambientColor will be used.)

       Note that nodes imported as part of a VRML V1.0 file has a special case, where the fields SoMaterial::ambientColor, SoMaterial::diffuseColor and SoMaterial::specularColor contains zero values, and SoMaterial::emissiveColor contains one or more values. The values in SoMaterial::emissiveColor should then be treated as precalculated lighting, and the other fields should be ignored.

       You can detect this case by checking the values of the material elements when the scene graph is traversed using an SoCallbackAction. SoDiffuseColorElement, SoAmbientColorElement, and SoSpecularColorElement will contain one value with a completely black color (0.0f, 0.0f, 0.0f), SoShininessElement will contain one value of 0.0f, and SoEmissiveColorElement will contain one or more values. It is done like this to make rendering work correctly on systems that do not test for this specific case.

       You should only check for this case when you're traversing a VRML V1.0 file scene graph, of course. See SoNode::getNodeType() for information about how nodes can be tested for whether or not they have been imported or otherwise set up as of VRML1 type versus Inventor type.

       When the scene graph is rendered using an SoGLRenderAction, the elements will be set differently to optimize rendering. The SoDiffuseColorElement will be set to the values in SoMaterial::emissiveColor, and the light model will be set to SoLightModel::BASE_COLOR.

       The SoMaterial::transparency values will always be treated normally.

       Here is a very simple usage example:

         #Inventor V2.1 ascii

         Separator {
            Coordinate3 {
               point [ 0 0 0, 1 0 0, 1 1 0 ]
            }

            Material {
               diffuseColor [ 1 0 0, 1 1 0, 0 0 1 ]
            }

            MaterialBinding {
               value PER_VERTEX
            }

            IndexedFaceSet {
               coordIndex [ 0, 1, 2, -1 ]
            }
         }
         .fi

       FILE FORMAT/DEFAULTS:

           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
           }

       See also:
           SoMaterialBinding, SoBaseColor, SoPackedColor

Constructor & Destructor Documentation

   SoMaterial::SoMaterial (void) Constructor.
   SoMaterial::~SoMaterial () [protected, virtual] Destructor.

Member Function Documentation

   void SoMaterial::initClass (void) [static] Sets up initialization for data common to all
       instances of this class, like submitting necessary information to the Coin type system.
       Reimplemented from SoNode.

   void SoMaterial::doAction (SoAction *action) [virtual] This function performs the typical
       operation of a node for any action.
       Reimplemented from SoNode.

   void SoMaterial::GLRender (SoGLRenderAction *action) [virtual] Action method for the
       SoGLRenderAction.
       This is called during rendering traversals. Nodes influencing the rendering state in any
       way or who wants to throw geometry primitives at OpenGL overrides this method.

       Reimplemented from SoNode.

   void SoMaterial::callback (SoCallbackAction *action) [virtual] Action method for
       SoCallbackAction.
       Simply updates the state according to how the node behaves for the render action, so the
       application programmer can use the SoCallbackAction for extracting information about the
       scene graph.

       Reimplemented from SoNode.

   void SoMaterial::notify (SoNotList *l) [protected, virtual] Notifies all auditors for this
       instance when changes are made.
       Reimplemented from SoNode.

Member Data Documentation

   SoMFColor SoMaterial::ambientColor Ambient material part color values. Will by default contain
       a single color value of [0.2, 0.2, 0.2] (ie dark gray).
       The ambient part of the material is not influenced by any lightsources, and should be
       thought of conceptually as the constant, but small contribution of light to a scene
       'seeping in' from everywhere.

       (Think of the ambient contribution in the context that there's always photons fizzing
       around everywhere -- even in a black, lightsource-less room, for instance).

       Only the first value in this field will be used. All other values will be ignored.

       See also:
           SoEnvironment::ambientIntensity

   SoMFColor SoMaterial::diffuseColor Diffuse material part color values. This field is by
       default initialized to contain a single color value of [0.8, 0.8, 0.8] (light gray).
       The diffuse part is combined with the light emitted from the scene's light sources.

       Traditional Open Inventor uses the same override bit for both diffuse color and
       transparency. To get around this problem if you need to override one without the other,
       set the environment variable 'COIN_SEPARATE_DIFFUSE_TRANSPARENCY_OVERRIDE'. This is a Coin
       extension, and will not work on the other Open Inventor implementations.

   SoMFColor SoMaterial::specularColor Specular material part color values. Defaults to a single
       color value of [0, 0, 0] (black).
       Only the first value in this field will be used. All other values will be ignored.

   SoMFColor SoMaterial::emissiveColor The color of the light 'emitted' by the subsequent
       geometry, independent of lighting / shading.
       Defaults to contain a single color value of [0, 0, 0] (black, ie no contribution).

       Only the first value in this field will be used. All other values will be ignored.

   SoMFFloat SoMaterial::shininess Shininess values. Decides how the light from light sources are
       distributed across the geometry surfaces. Valid range is from 0.0 (which gives a dim
       appearance), to 1.0 (glossy-looking surfaces).
       Defaults to contain a single value of 0.2.

       Only the first value in this field will be used. All other values will be ignored.

   SoMFFloat SoMaterial::transparency Transparency values. Valid range is from 0.0 (completely
       opaque, which is the default) to 1.0 (completely transparent, i.e. invisible).
       Defaults to contain a single value of 0.0.

       Traditional Open Inventor uses the same override bit for both transparency and diffuse
       color. To get around this problem if you need to override one without the other, set the
       environment variable 'COIN_SEPARATE_DIFFUSE_TRANSPARENCY_OVERRIDE'. This is a Coin
       extension, and will not work on the other Open Inventor implementations.

Author

       Generated automatically by Doxygen for Coin from the source code.