CollisionHandlerEvent

class CollisionHandlerEvent

Bases: CollisionHandler

A specialized kind of CollisionHandler that throws an event for each collision detected. The event thrown may be based on the name of the moving object or the struck object, or both. The first parameter of the event will be a pointer to the CollisionEntry that triggered it.

Inheritance diagram

Inheritance diagram of CollisionHandlerEvent

CollisionHandlerEvent(void)
CollisionHandlerEvent(CollisionHandlerEvent const&) = default

The default CollisionHandlerEvent will throw no events. Its pattern strings must first be set via a call to add_in_pattern() and/or add_out_pattern().

void add_again_pattern(std::string const &again_pattern)

Adds the pattern string that indicates how the event names are generated when a collision between two particular nodes is still detected. This event is thrown each consecutive time a collision between two particular nodes is detected, starting with the second time.

In general, the in_pattern event is thrown on the first detection of a collision between two particular nodes. In subsequent passes, as long as a collision between those two nodes continues to be detected each frame, the again_pattern is thrown. The first frame in which the collision is no longer detected, the out_pattern event is thrown.

void add_in_pattern(std::string const &in_pattern)

Adds a pattern string to the list of events that will be generated in response to a collision. The pattern string describes how the event name will be composed. It is a string that may contain any of the following:

%fn - the name of the “from” object’s node %in - the name of the “into” object’s node %fs - ‘t’ if “from” is tangible, ‘i’ if intangible %is - ‘t’ if “into” is tangible, ‘i’ if intangible %ig - ‘c’ if the collision is into a CollisionNode, ‘g’ if it is a geom.

%(tag)fh - generate event only if “from” node has the indicated net tag. %(tag)fx - generate event only if “from” node does not have the indicated net tag. %(tag)ih - generate event only if “into” node has the indicated net tag. %(tag)ix - generate event only if “into” node does not have the indicated net tag. %(tag)ft - the indicated net tag value of the “from” node. %(tag)it - the indicated net tag value of the “into” node.

Parentheses in the above are literal and should be included in the actual pattern.

The event name will be based on the in_pattern string specified here, with all occurrences of the above strings replaced with the corresponding values.

In general, the in_pattern event is thrown on the first detection of a collision between two particular nodes. In subsequent passes, as long as a collision between those two nodes continues to be detected each frame, the again_pattern is thrown. The first frame in which the collision is no longer detected, the out_pattern event is thrown.

void add_out_pattern(std::string const &out_pattern)

Adds the pattern string that indicates how the event names are generated when a collision between two particular nodes is no longer detected.

In general, the in_pattern event is thrown on the first detection of a collision between two particular nodes. In subsequent passes, as long as a collision between those two nodes continues to be detected each frame, the again_pattern is thrown. The first frame in which the collision is no longer detected, the out_pattern event is thrown.

void clear(void)

Empties the list of elements that all colliders are known to be colliding with. No “out” events will be thrown; if the same collision is detected next frame, a new “in” event will be thrown for each collision.

This can be called each frame to defeat the persistent “in” event mechanism, which prevents the same “in” event from being thrown repeatedly. However, also see add_again_pattern(), which can be used to set the event that is thrown when a collision is detected for two or more consecutive frames.

void clear_again_patterns(void)

Removes all of the previously-added in patterns. See add_again_pattern.

void clear_in_patterns(void)

Removes all of the previously-added in patterns. See add_in_pattern.

void clear_out_patterns(void)

Removes all of the previously-added in patterns. See add_out_pattern.

void flush(void)

Same as clear() except “out” events are thrown.

std::string get_again_pattern(int n) const

Returns the nth pattern string that indicates how the event names are generated for each collision detected. See add_again_pattern().

static TypeHandle get_class_type(void)
std::string get_in_pattern(int n) const

Returns the nth pattern string that indicates how the event names are generated for each collision detected. See add_in_pattern().

int get_num_again_patterns(void) const

Returns the number of in pattern strings that have been added.

int get_num_in_patterns(void) const

Returns the number of in pattern strings that have been added.

int get_num_out_patterns(void) const

Returns the number of in pattern strings that have been added.

std::string get_out_pattern(int n) const

Returns the nth pattern string that indicates how the event names are generated for each collision detected. See add_out_pattern().

void read_datagram(DatagramIterator &source)

Restores the object state from the given datagram, previously obtained using __getstate__.

void set_again_pattern(std::string const &again_pattern)

This method is deprecated; it completely replaces all the in patterns that have previously been set with the indicated pattern.

Deprecated: Use add_again_pattern() instead.

void set_in_pattern(std::string const &in_pattern)

This method is deprecated; it completely replaces all the in patterns that have previously been set with the indicated pattern.

Deprecated: Use add_in_pattern() instead.

void set_out_pattern(std::string const &out_pattern)

This method is deprecated; it completely replaces all the in patterns that have previously been set with the indicated pattern.

Deprecated: Use add_out_pattern() instead.

void write_datagram(Datagram &destination) const

Serializes this object, to implement pickle support.