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SoTextureCoordinatePlane.3coin2

NAME

SoTextureCoordinatePlane -

The SoTextureCoordinatePlane class generates texture coordinates by projecting onto a plane.

SoTextureCoordinatePlane is used for generating texture coordinates by projecting the object onto a texture plane. The s and t texture coordinates are computed as the distance from the origin to the projected point, in the respective directions. The texture plane is specified using two direction vectors, given as SoTextureCoordinatePlane::directionS and SoTextureCoordinatePlane::directionT in object space coordinates. The length of the vector determines the repeat interval of the texture per unit length.

SYNOPSIS

#include <Inventor/nodes/SoTextureCoordinatePlane.h>

Inherits SoTextureCoordinateFunction.

Public Member Functions

SoTextureCoordinatePlane (void)

virtual void doAction (SoAction *action)

virtual void GLRender (SoGLRenderAction *action)

virtual void pick (SoPickAction *action)

virtual void callback (SoCallbackAction *action)

Static Public Member Functions

static void initClass (void)

Public Attributes

SoSFVec3f directionS

SoSFVec3f directionT

Protected Member Functions

virtual ~SoTextureCoordinatePlane ()

Detailed Description

The SoTextureCoordinatePlane class generates texture coordinates by projecting onto a plane.

SoTextureCoordinatePlane is used for generating texture coordinates by projecting the object onto a texture plane. The s and t texture coordinates are computed as the distance from the origin to the projected point, in the respective directions. The texture plane is specified using two direction vectors, given as SoTextureCoordinatePlane::directionS and SoTextureCoordinatePlane::directionT in object space coordinates. The length of the vector determines the repeat interval of the texture per unit length.

A simple usage example:

   SoSeparator *root = new SoSeparator;
   root->ref();
   
   // the texture image
   SoTexture2 *tex = new SoTexture2;
   tex->filename.setValue('foo.png');
   root->addChild(tex);
   
   // the texture plane
   SoTextureCoordinatePlane *texPlane = new SoTextureCoordinatePlane;
   texPlane->directionS.setValue(SbVec3f(1,0,0));
   texPlane->directionT.setValue(SbVec3f(0,1,0));
   root->addChild(texPlane);
   
   // add a simple cube
   SoCube * c = new SoCube;
   c->width.setValue(1.0);
   c->height.setValue(1.0)
   c->depth.setValue(1.0);
   root->addChild(new SoCube);
 

Here, we are projecting a texture onto a cube. The texture coordinate plane is specified by directionS = (1,0,0) and directionT = (0,1,0), meaning that it is parallel to the front face of the cube. Setting e.g. directionS = (0,1,0) and directionT = (-1,0,0) would rotate the texture counterclockwise by 90 degrees. Setting them to ((2,0,0), (0,2,0)) results to the texture being repeated twice per unit, so the texture appears four times on the 1x1 face.

Note that when you transform the cube, the transformation will also affect the texture - it will be transformed vs. the rest of the world, but appear 'fixed' on the object. If you want to change the placement of the texture on the object, you have to insert a SoTexture2Transform node before the texture coordinate plane. For instance in the example above, since the cube is centered in its coordinate system, the lower left corner of the texture appears to be in the middle of the face. To move the texture's origin to coincide with the lower left corner of the face, insert

   SoTexture2Transform * tf = new SoTexture2Transform;
   tf->translation.setValue(-0.5,-0.5);
   root->addChild(tf);
 

before adding the texture coordinate plane.

FILE FORMAT/DEFAULTS:

     TextureCoordinatePlane {
         directionS 1 0 0
         directionT 0 1 0
     }
 
 

 

Constructor & Destructor Documentation

SoTextureCoordinatePlane::SoTextureCoordinatePlane (void)Constructor.

References directionS, and directionT.

SoTextureCoordinatePlane::~SoTextureCoordinatePlane () [protected, virtual]Destructor.

Member Function Documentation

void SoTextureCoordinatePlane::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 SoTextureCoordinateFunction.

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

Reimplemented from SoNode.

References SoAction::getState().

Referenced by callback(), GLRender(), and pick().

void SoTextureCoordinatePlane::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 doAction(), SoFieldContainer::get(), and SoAction::getState().

void SoTextureCoordinatePlane::pick (SoPickAction * action) [virtual]Action method for SoPickAction.

Does common processing for SoPickAction action instances.

Reimplemented from SoNode.

References doAction().

void SoTextureCoordinatePlane::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.

References doAction().

Member Data Documentation

SoSFVec3f SoTextureCoordinatePlane::directionSThe S texture coordinate plane direction. The length of the vector determines the repeat interval of the texture per unit length.

Referenced by SoTextureCoordinatePlane().

SoSFVec3f SoTextureCoordinatePlane::directionTThe T texture coordinate plane direction. The length of the vector determines the repeat interval of the texture per unit length.

Referenced by SoTextureCoordinatePlane().

Author

Generated automatically by Doxygen for Coin from the source code.