# SoIntersectionDetectionAction Class Reference
[Actions, Collision detections between scene geometry]

`#include <Inventor/collision/SoIntersectionDetectionAction.h>`

Inheritance diagram for SoIntersectionDetectionAction:

List of all members.

## Detailed Description

The SoIntersectionDetectionAction class is for detecting intersecting primitives in a scene.

Below is a simple usage example for this class. It was written as a stand-alone framework set up for profiling and optimization of the SoIntersectionDetectionAction. It tests intersection of all shapes against each other for the loaded file.

      #include <stdlib.h>
      #include <Inventor/SbTime.h>
      #include <Inventor/SoDB.h>
      #include <Inventor/SoInteraction.h>
      #include <Inventor/collision/SoIntersectionDetectionAction.h>
      #include <Inventor/errors/SoDebugError.h>
      #include <Inventor/nodekits/SoNodeKit.h>
      #include <Inventor/nodes/SoSeparator.h>

      static SoIntersectionDetectionAction::Resp
      intersectionCB(void * closure,
                     const SoIntersectingPrimitive * pr1,
                     const SoIntersectingPrimitive * pr2)
      {
        (void)fprintf(stdout, "intersection hit!\n");
        return SoIntersectionDetectionAction::NEXT_PRIMITIVE;
      }

      int
      main(int argc, char ** argv)
      {
        SoDB::init();
        SoNodeKit::init();
        SoInteraction::init();

        if (argc != 2) {
          (void)fprintf(stderr, "\n\tUsage: testapp <filename.iv>\n\n");
          exit(1);
        }

        SoInput in;
        SbBool ok = in.openFile(argv[1]);
        assert(ok);
        SoSeparator * root = SoDB::readAll(&in);
        assert(root);

        root->ref();

        SoIntersectionDetectionAction ida;
        ida.addIntersectionCallback(intersectionCB, NULL);
        ida.setManipsEnabled(FALSE);
        ida.setDraggersEnabled(FALSE);
        ida.setIntersectionDetectionEpsilon(10.0f);

        SbTime starttime = SbTime::getTimeOfDay();
        SoDebugError::postInfo("main", "SoIntersectionDetectionAction::apply");

        ida.apply(root);

        SoDebugError::postInfo("main", "apply() done after %f seconds.",
                               (SbTime::getTimeOfDay() - starttime).getValue());

        root->unref();

        return 0;
      }

Since:
  Coin 2.1

  TGS Inventor 2.4

## Public Types

typedef SoCallbackAction::Response | SoIntersectionVisitationCB (void *closure, const SoPath *where)
typedef SbBool | SoIntersectionFilterCB (void *closure, const SoPath *p1, const SoPath *p2)
typedef Resp | SoIntersectionCB (void *closure, const SoIntersectingPrimitive *p1, const SoIntersectingPrimitive *p2)
enum | Resp { NEXT_PRIMITIVE, NEXT_SHAPE, ABORT }

## Public Member Functions

void | setIntersectionDetectionEpsilon (float epsilon)
float | getIntersectionDetectionEpsilon (void) const
void | setTypeEnabled (SoType type, SbBool enable)
SbBool | isTypeEnabled (SoType type, SbBool checkgroups=FALSE) const
void | setManipsEnabled (SbBool enable)
SbBool | isManipsEnabled (void) const
void | setDraggersEnabled (SbBool enable)
SbBool | isDraggersEnabled (void) const
void | setShapeInternalsEnabled (SbBool enable)
SbBool | isShapeInternalsEnabled (void) const
void | addVisitationCallback (SoType type, SoIntersectionVisitationCB *cb, void *closure)
void | removeVisitationCallback (SoType type, SoIntersectionVisitationCB *cb, void *closure)
virtual void | apply (SoNode *node)
virtual void | apply (SoPath *path)
virtual void | apply (const SoPathList &paths, SbBool obeysRules=FALSE)
virtual void | setFilterCallback (SoIntersectionFilterCB *cb, void *closure=NULL)
virtual void | addIntersectionCallback (SoIntersectionCB *cb, void *closure=NULL)
virtual void | removeIntersectionCallback (SoIntersectionCB *cb, void *closure=NULL)

## Static Public Member Functions

void | initClass (void)
void | setIntersectionEpsilon (float epsilon)
float | getIntersectionEpsilon (void)

## Member Function Documentation

void SoIntersectionDetectionAction::initClass | ( | void |  | ) | `[static]`

| Initializes the run-time type system for this class, and sets up the enabled elements and action method list. Reimplemented from SoAction.

void SoIntersectionDetectionAction::setIntersectionDetectionEpsilon | ( | float | epsilon | ) |

| Sets the intersection detection distance epsilon value for the action object. This overrides the global value. See also SoIntersectionDetectionAction::setIntersectionEpsilon() for important information about how this setting influences performance.

float SoIntersectionDetectionAction::getIntersectionDetectionEpsilon | ( | void |  | ) | const

| Returns the set intersection detection distance epsilon value for the action object.

void SoIntersectionDetectionAction::setIntersectionEpsilon | ( | float | epsilon | ) | `[static]`

Sets the global intersection detection distance epsilon value. This will affect all intersection detection action objects in use that don't have a locally set value.

The epsilon value is a worldspace value.

Be aware that increasing the epsilon value can dramatically increase the number of primitive intersection tests being done to decide intersections. Increasing the epsilon value can therefore cause serious slow-downs in the running time of the intersections checks.

Epsilon is not supported yet.

float SoIntersectionDetectionAction::getIntersectionEpsilon | ( | void |  | ) | `[static]`

| Returns the globally set intersection detection distance epsilon value.

void SoIntersectionDetectionAction::setTypeEnabled | ( | SoType | type,
|  | SbBool | enable
| ) |

Sets whether nodes of specific types (including derived objects) should be tested for intersection or not.

See also:
  isTypeEnabled(), setManipsEnabled(), setDraggersEnabled()

SbBool SoIntersectionDetectionAction::isTypeEnabled | ( | SoType | type,
|  | SbBool | checkgroups = FALSE
| ) | const

Returns whether nodes of specific types are enabled or not. The checkgroups argument can be set to TRUE if you wan't the return value to reflect whether the node will be implicit enabled/disabled through the settings controlled by the setManipsEnabled() and setDraggersEnabled() functions.

The default is that all node types are enabled.

Note that derivation checks are not performed - the type needs to be the exact same type as has been disabled with setTypeEnabled()

See also:
  setTypeEnabled()

void SoIntersectionDetectionAction::setManipsEnabled | ( | SbBool | enable | ) |

Sets whether manipulators in the scene graph should be tested for intersection with other geometry or not.

Note that when draggers are disabled with setDraggersEnabled(), this setting has no effect - manipulators are disabled too.

See also:
  isManipsEnabled(), setDraggersEnabled(), setTypeEnabled()

SbBool SoIntersectionDetectionAction::isManipsEnabled | ( | void |  | ) | const

Returns whether the actions is set up to test intersection on manipulators in the scene or not.

Note that when draggers are disabled with setDraggersEnabled(), this setting has no effect - manipulators are disabled too.

The default is that manipulators are enabled for intersection testing with other geometry in the scene.

See also:
  setManipsEnabled()

void SoIntersectionDetectionAction::setDraggersEnabled | ( | SbBool | enable | ) |

Sets whether draggers in the scene graph should be tested for intersection with other geometry or not.

Note that when you disable draggers, manipulators are also automatically disabled, although the isManipsDisabled() setting might reflect otherwise.

See also:
  isDraggersEnabled(), setManipsEnabled(), setTypeEnabled()

SbBool SoIntersectionDetectionAction::isDraggersEnabled | ( | void |  | ) | const

Returns whether the actions is set up to test intersection on draggers in the scene or not.

The default is that draggers are enabled for intersection testing with other geometry in the scene.

See also:
  setDraggersEnabled()

void SoIntersectionDetectionAction::setShapeInternalsEnabled | ( | SbBool | enable | ) |

Sets whether nodes in the scene graph should be checked for intersecting primitives within themselves.

Default is `FALSE`.

See also:
  isShapeInternalsEnabled()

SbBool SoIntersectionDetectionAction::isShapeInternalsEnabled | ( | void |  | ) | const

Returns whether nodes in the scene graph will be checked for intersecting primitives within themselves.

The default value for this setting is `FALSE`.

See also:
  setShapeInternalsEnabled()

void SoIntersectionDetectionAction::addVisitationCallback | ( | SoType | type,
|  | SoIntersectionVisitationCB * | cb,
|  | void * | closure
| ) |

The scene graph traversal can be controlled with callbacks which you set with this method. Use just like you would use SoCallbackAction::addPreCallback().

See also:
  SoCallbackAction::addPreCallback()

void SoIntersectionDetectionAction::removeVisitationCallback | ( | SoType | type,
|  | SoIntersectionVisitationCB * | cb,
|  | void * | closure
| ) |

The scene graph traversal can be controlled with callbacks which you remove with this method. Use just like you would use SoCallbackAction::removePreCallback().

See also:
  SoCallbackAction::removePreCallback()

void SoIntersectionDetectionAction::apply | ( | SoNode * | node | ) | `[virtual]`

| Applies the action to the scene graph rooted at root. Note that you should not apply an action to a node with a zero reference count. The behavior in that case is undefined. Reimplemented from SoAction.

void SoIntersectionDetectionAction::apply | ( | SoPath * | path | ) | `[virtual]`

| Applies the action to the parts of the graph defined by path. If the path ends in an SoGroup node, the action will also traverse the tail node's children. Reimplemented from SoAction.

void SoIntersectionDetectionAction::apply | ( | const SoPathList & | paths,
|  | SbBool | obeysRules = FALSE
| ) | `[virtual]`

Applies action to the graphs defined by pathlist. If obeysrules is set to `TRUE`, pathlist must obey the following four conditions (which is the case for path lists returned from search actions for non-group nodes and path lists returned from picking actions):

All paths must start at the same head node. All paths must be sorted in traversal order. The paths must be unique. No path can continue through the end point of another path.

Reimplemented from SoAction.

void SoIntersectionDetectionAction::setFilterCallback | ( | SoIntersectionFilterCB * | cb,
|  | void * | closure = NULL
| ) | `[virtual]`

This callback is called when two shapes are found to have intersecting bounding boxes, and are about to be checked for real intersection between their primitives.

When intersection epsilon values are in use, bounding box intersection testing is done approximately and will trigger the filter callback on boxes that are further from each other than the epsilon length.

If the callback returns TRUE, the intersection test will be performed. If the callback returns FALSE, the intersection testing will be skipped.

The API allows only one filter callback.

void SoIntersectionDetectionAction::addIntersectionCallback | ( | SoIntersectionCB * | cb,
|  | void * | closure = NULL
| ) | `[virtual]`

Adds a callback to be called when two intersecting primitives are found in the scene.

If the callback returns ABORT, the intersection detection is aborted. If the callback returns NEXT_SHAPE, the intersection detection between these two shapes are aborted and the action continues checking other shapes. If the callback returns NEXT_PRIMITIVE, the intersection detection testing continues checking the other primitives in these two shapes.

See also:
  removeIntersectionCallback()

void SoIntersectionDetectionAction::removeIntersectionCallback | ( | SoIntersectionCB * | cb,
|  | void * | closure = NULL
| ) | `[virtual]`

Removes a callback set with addIntersectionCallback().

See also:
  addIntersectionCallback()

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

- SoIntersectionDetectionAction.h
- SoIntersectionDetectionAction.cpp