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Public Types | Public Member Functions | Static Public Member Functions | Public Attributes | Protected Member Functions

SoBumpMap Class Reference

The SoBumpMap class is used to map a bump map onto subsequent shapes.SoBumpMap has support for two types of maps. If the image is a three component (RGB) image, it will be treated as a normal map, where the red image component equals the X normal component, green equals Y, and blue is Z. See http://www.paulsprojects.net/tutorials/simplebump/simplebump.html for a nice introduction about bump mapping and normal maps. More...

#include <Inventor/nodes/SoBumpMap.h>

Inheritance diagram for SoBumpMap:
SoNode SoFieldContainer SoBase

List of all members.

Public Types

enum  Wrap { REPEAT = SoTextureImageElement::REPEAT, CLAMP = SoTextureImageElement::CLAMP }

Public Member Functions

 SoBumpMap (void)
virtual void doAction (SoAction *action)
virtual void GLRender (SoGLRenderAction *action)
virtual void callback (SoCallbackAction *action)
virtual void rayPick (SoRayPickAction *action)

Static Public Member Functions

static void initClass (void)
static SbBool readImage (const SbString &fname, int &w, int &h, int &nc, unsigned char *&bytes)

Public Attributes

SoSFString filename
SoSFImage image
SoSFEnum wrapS
SoSFEnum wrapT

Protected Member Functions

virtual ~SoBumpMap ()
virtual SbBool readInstance (SoInput *in, unsigned short flags)
virtual void notify (SoNotList *list)

Detailed Description

The SoBumpMap class is used to map a bump map onto subsequent shapes.

SoBumpMap has support for two types of maps. If the image is a three component (RGB) image, it will be treated as a normal map, where the red image component equals the X normal component, green equals Y, and blue is Z. See http://www.paulsprojects.net/tutorials/simplebump/simplebump.html for a nice introduction about bump mapping and normal maps.

If the image is a grayscale image, it will be treated as a height map, and automatically converted to a normal map.

For bump mapping to work with extension nodes for Coin, the SoShape::generatePrimitives() method must be correctly implemented for the shape. This is needed since tangent space coordinates needs to be calculated for each vertex in the shape. All shape nodes which are a standard part of Coin meets this criteria.

Bump mapping in Coin requires OpenGL 1.3, or the following OpenGL extensions: GL_ARB_multitexture, GL_ARB_texture_cube_map, GL_ARB_texture_env_combine and GL_ARB_texture_env_dot3 (or the corresponding EXT extensions). If the run-time system doesn't meet these requirements, Coin will post a warning and the bump map will simply be ignored.

GL_ARB_vertex_program and GL_ARB_fragment_program is required to get specular lighting on the bumps. If these extensions are not available, the bumps will be rendered with diffuse lighting only.

Bump mapped objects will be rendered with multiple rendering passes. One extra pass per light source for diffuse only bumps, and two extra passes per light source for diffuse and specular bumps. You can turn off specular lighting on the bumps by setting specularColor to (0.0, 0.0, 0.0).

FILE FORMAT/DEFAULTS:

    BumpMap {
        filename ""
        image 0 0 0

        wrapS REPEAT
        wrapT REPEAT
    }
Since:
Coin 2.2

Member Enumeration Documentation

Enumeration of wrapping strategies which can be used when the bump map doesn't cover the full extent of the geometry.

Enumerator:
REPEAT 

Repeat bump map when coordinate is not between 0 and 1.

CLAMP 

Clamp coordinate between 0 and 1.


Constructor & Destructor Documentation

SoBumpMap::SoBumpMap ( void  )

Constructor.

References CLAMP, filename, image, REPEAT, wrapS, and wrapT.

SoBumpMap::~SoBumpMap ( ) [protected, virtual]

Destructor. Frees up internal resources used to store texture image data.


Member Function Documentation

void SoBumpMap::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 SoBumpMap::doAction ( SoAction action) [virtual]

This function performs the typical operation of a node for any action.

Reimplemented from SoNode.

References SoAction::getState(), SoSFImage::getValue(), and image.

Referenced by rayPick().

void SoBumpMap::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.

References SoGLRenderAction::getCacheContext(), SoAction::getState(), SoSFImage::getValue(), image, SoDebugError::postWarning(), SoFieldContainer::set(), wrapS, and wrapT.

void SoBumpMap::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 SoBumpMap::rayPick ( SoRayPickAction action) [virtual]

Action method for SoRayPickAction.

Checks the ray specification of the action and tests for intersection with the data of the node.

Nodes influencing relevant state variables for how picking is done also overrides this method.

Reimplemented from SoNode.

References doAction().

SbBool SoBumpMap::readImage ( const SbString fname,
int &  w,
int &  h,
int &  nc,
unsigned char *&  bytes 
) [static]

Not implemented. Was added to the API by mistake. Will be removed in Coin 3.

SbBool SoBumpMap::readInstance ( SoInput in,
unsigned short  flags 
) [protected, virtual]

This method is mainly intended for internal use during file import operations.

It reads a definition of an instance from the input stream in. The input stream state points to the start of a serialized / persistant representation of an instance of this class type.

TRUE or FALSE is returned, depending on if the instantiation and configuration of the new object of this class type went ok or not. The import process should be robust and handle corrupted input streams by returning FALSE.

flags is used internally during binary import when reading user extension nodes, group nodes or engines.

Reimplemented from SoNode.

References filename, SbString::getString(), SoField::isDefault(), SoReadError::post(), and SoNode::readInstance().

void SoBumpMap::notify ( SoNotList l) [protected, virtual]

Notifies all auditors for this instance when changes are made.

Reimplemented from SoNode.

References filename, SoNotList::getLastField(), image, SoNode::notify(), and SoField::setDefault().


Member Data Documentation

Bump map (or normal map) filename, referring to a file on disk in a supported image bitmap format. See SoBumpMap::filename for more information.

Referenced by notify(), readInstance(), and SoBumpMap().

Inline image data. Defaults to contain an empty bump map.

Referenced by doAction(), GLRender(), notify(), and SoBumpMap().

Wrapping strategy for the S coordinate when the bump map is narrower than the object to map onto.

Default value is SoBumpMap::REPEAT.

Referenced by GLRender(), and SoBumpMap().

Wrapping strategy for the T coordinate when the bump map is shorter than the object to map onto.

Default value is SoBumpMap::REPEAT.

Referenced by GLRender(), and SoBumpMap().


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

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