# LightAttrib

from pandac.PandaModules import LightAttrib

Class : LightAttrib
Description : Indicates which set of lights should be considered "on" to illuminate geometry at this level and below. A LightAttrib can either add lights or remove lights from the total set of "on" lights.

## Inheritance:

LightAttrib: RenderAttrib
RenderAttrib: TypedWritableReferenceCount
TypedWritableReferenceCount: TypedWritable ReferenceCount
TypedWritable: TypedObject
TypedObject: MemoryBase
MemoryBase:
ReferenceCount: MemoryBase

## Methods of LightAttrib:

addLight
addOffLight
addOnLight
filterToMax
getClassSlot
getClassType
getLight
getMostImportantLight
getNumLights
getNumOffLights
getNumOnLights
getOffLight
getOnLight
getOperation
hasAllOff
hasLight
hasOffLight
hasOnLight
isIdentity
make
makeAllOff
makeDefault
removeLight
removeOffLight
removeOnLight

## Methods of RenderAttrib:

compareTo
getClassType
getNumAttribs
getSlot
getUnique
listAttribs
output
unref
validateAttribs
write

## Methods of TypedWritableReferenceCount:

getClassType

## Methods of TypedWritable:

getClassType

## Methods of TypedObject:

getClassType
getType
getTypeIndex
isExactType
isOfType

## Methods of ReferenceCount:

getClassType
getRefCount
ref
testRefCountIntegrity
testRefCountNonzero
unref

## Constants in LightAttrib:

OSet | (Operation)
OAdd | (Operation)
ORemove | (Operation)

## Constants in RenderAttrib:

MNone | (PandaCompareFunc)
MNever | (PandaCompareFunc)
MLess | (PandaCompareFunc)
MEqual | (PandaCompareFunc)
MLessEqual | (PandaCompareFunc)
MGreater | (PandaCompareFunc)
MNotEqual | (PandaCompareFunc)
MGreaterEqual | (PandaCompareFunc)
MAlways | (PandaCompareFunc)
MOff | (TexGenMode)
MEyeSphereMap | (TexGenMode)
MWorldCubeMap | (TexGenMode)
MEyeCubeMap | (TexGenMode)
MWorldNormal | (TexGenMode)
MEyeNormal | (TexGenMode)
MWorldPosition | (TexGenMode)
MUnused | (TexGenMode)
MEyePosition | (TexGenMode)
MPointSprite | (TexGenMode)
MLightVector | (TexGenMode)
MConstant | (TexGenMode)

addLight ConstPointerTo< RenderAttrib > LightAttrib::add_light(Light *light) const; Description: Returns a new LightAttrib, just like this one, but with the indicated light added to the list of lights. This method is now deprecated. Use add_on_light() or add_off_light() instead.

addOffLight ConstPointerTo< RenderAttrib > LightAttrib::add_off_light(NodePath const &light) const; Description: Returns a new LightAttrib, just like this one, but with the indicated light added to the list of lights turned off by this attrib.

addOnLight ConstPointerTo< RenderAttrib > LightAttrib::add_on_light(NodePath const &light) const; Description: Returns a new LightAttrib, just like this one, but with the indicated light added to the list of lights turned on by this attrib.

filterToMax ConstPointerTo< LightAttrib > LightAttrib::filter_to_max(int max_lights) const; Description: Returns a new LightAttrib, very much like this one, but with the number of on_lights reduced to be no more than max_lights. The number of off_lights in the new LightAttrib is undefined. The number of AmbientLights is not included in the count. All AmbientLights in the original attrib are always included in the result, regardless of the value of max_lights.

getClassSlot static int LightAttrib::get_class_slot(void); Undocumented function.

getClassType static TypeHandle LightAttrib::get_class_type(void); Undocumented function.

getLight Light *LightAttrib::get_light(int n) const; Description: Returns the nth light listed in the attribute. This method is now deprecated. LightAttribs nowadays have a separate list of on_lights and off_lights, so this method doesn't make sense. Query the lists independently.

getMostImportantLight NodePath LightAttrib::get_most_important_light(void) const; Description: Returns the most important light (that is, the light with the highest priority) in the LightAttrib, excluding any ambient lights. Returns an empty NodePath if no non-ambient lights are found.

getNumLights int LightAttrib::get_num_lights(void) const; Description: Returns the number of lights listed in the attribute. This method is now deprecated. LightAttribs nowadays have a separate list of on_lights and off_lights, so this method doesn't make sense. Query the lists independently.

getNumOffLights int LightAttrib::get_num_off_lights(void) const; Description: Returns the number of lights that are turned off by the attribute.

getNumOnLights int LightAttrib::get_num_on_lights(void) const; Description: Returns the number of lights that are turned on by the attribute.

getOffLight NodePath LightAttrib::get_off_light(int n) const; Description: Returns the nth light turned off by the attribute, sorted in arbitrary (pointer) order.

getOnLight NodePath LightAttrib::get_on_light(int n) const; Description: Returns the nth light turned on by the attribute, sorted in render order.

getOperation LightAttrib::Operation LightAttrib::get_operation(void) const; Description: Returns the basic operation type of the LightAttrib. If this is O_set, the lights listed here completely replace any lights that were already on. If this is O_add, the lights here are added to the set of of lights that were already on, and if O_remove, the lights here are removed from the set of lights that were on. This method is now deprecated. LightAttribs nowadays have a separate list of on_lights and off_lights, so this method doesn't make sense. Query the lists independently.

hasAllOff bool LightAttrib::has_all_off(void) const; Description: Returns true if this attrib turns off all lights (although it may also turn some on).

hasLight bool LightAttrib::has_light(Light *light) const; Description: Returns true if the indicated light is listed in the attrib, false otherwise. This method is now deprecated. LightAttribs nowadays have a separate list of on_lights and off_lights, so this method doesn't make sense. Query the lists independently.

hasOffLight bool LightAttrib::has_off_light(NodePath const &light) const; Description: Returns true if the indicated light is turned off by the attrib, false otherwise.

hasOnLight bool LightAttrib::has_on_light(NodePath const &light) const; Description: Returns true if the indicated light is turned on by the attrib, false otherwise.

isIdentity bool LightAttrib::is_identity(void) const; Description: Returns true if this is an identity attrib: it does not change the set of lights in use.

make static ConstPointerTo< RenderAttrib > LightAttrib::make(LightAttrib::Operation op, Light *light); The following is the new, more general interface to the LightAttrib. Description: Constructs a new LightAttrib object that turns on (or off, according to op) the indicated light(s). This method is now deprecated. Use add_on_light() or add_off_light() instead. Description: Constructs a new LightAttrib object that turns on (or off, according to op) the indicate light(s). Description: Constructs a new LightAttrib object that does nothing.

makeAllOff static ConstPointerTo< RenderAttrib > LightAttrib::make_all_off(void); The following is the new, more general interface to the LightAttrib. Description: Constructs a new LightAttrib object that turns off all lights (and hence disables lighting).

makeDefault static ConstPointerTo< RenderAttrib > LightAttrib::make_default(void); Description: Returns a RenderAttrib that corresponds to whatever the standard default properties for render attributes of this type ought to be.

removeLight ConstPointerTo< RenderAttrib > LightAttrib::remove_light(Light *light) const; Description: Returns a new LightAttrib, just like this one, but with the indicated light removed from the list of lights. This method is now deprecated. Use remove_on_light() or remove_off_light() instead.

removeOffLight ConstPointerTo< RenderAttrib > LightAttrib::remove_off_light(NodePath const &light) const; Description: Returns a new LightAttrib, just like this one, but with the indicated light removed from the list of lights turned off by this attrib.

removeOnLight ConstPointerTo< RenderAttrib > LightAttrib::remove_on_light(NodePath const &light) const; Description: Returns a new LightAttrib, just like this one, but with the indicated light removed from the list of lights turned on by this attrib.

compareTo int RenderAttrib::compare_to(RenderAttrib const &other) const; Description: Provides an arbitrary ordering among all unique RenderAttribs, so we can store the essentially different ones in a big set and throw away the rest. This method is not needed outside of the RenderAttrib class because all equivalent RenderAttrib objects are guaranteed to share the same pointer; thus, a pointer comparison is always sufficient.

getClassType static TypeHandle RenderAttrib::get_class_type(void); Undocumented function.

getNumAttribs static int RenderAttrib::get_num_attribs(void); Description: Returns the total number of unique RenderAttrib objects allocated in the world. This will go up and down during normal operations.

getSlot virtual int RenderAttrib::get_slot(void) const = 0; Undocumented function.

getUnique ConstPointerTo< RenderAttrib > RenderAttrib::get_unique(void) const; Description: Returns the pointer to the unique RenderAttrib in the cache that is equivalent to this one. This may be the same pointer as this object, or it may be a different pointer; but it will be an equivalent object, and it will be a shared pointer. This may be called from time to time to improve cache benefits.

listAttribs static void RenderAttrib::list_attribs(ostream &out); Description: Lists all of the RenderAttribs in the cache to the output stream, one per line. This can be quite a lot of output if the cache is large, so be prepared.

output virtual void RenderAttrib::output(ostream &out) const; Description:

unref bool RenderAttrib::unref(void) const; Description: This method overrides ReferenceCount::unref() to clear the pointer from the global object pool when its reference count goes to zero.

validateAttribs static bool RenderAttrib::validate_attribs(void); Description: Ensures that the cache is still stored in sorted order. Returns true if so, false if there is a problem (which implies someone has modified one of the supposedly-const RenderAttrib objects).

write virtual void RenderAttrib::write(ostream &out, int indent_level) const; Description:

getClassType static TypeHandle TypedWritableReferenceCount::get_class_type(void); Undocumented function.

getClassType static TypeHandle TypedWritable::get_class_type(void); Undocumented function.

getClassType static TypeHandle TypedObject::get_class_type(void); Undocumented function.

getType virtual TypeHandle TypedObject::get_type(void) const = 0; Derived classes should override this function to return get_class_type().

getTypeIndex int TypedObject::get_type_index(void) const; Description: Returns the internal index number associated with this object's TypeHandle, a unique number for each different type. This is equivalent to get_type().get_index().

isExactType bool TypedObject::is_exact_type(TypeHandle handle) const; Description: Returns true if the current object is the indicated type exactly.

isOfType bool TypedObject::is_of_type(TypeHandle handle) const; Description: Returns true if the current object is or derives from the indicated type.

getClassType static TypeHandle ReferenceCount::get_class_type(void); Undocumented function.

getRefCount int ReferenceCount::get_ref_count(void) const; Description: Returns the current reference count.

ref void ReferenceCount::ref(void) const; Description: Explicitly increments the reference count. User code should avoid using ref() and unref() directly, which can result in missed reference counts. Instead, let a PointerTo object manage the reference counting automatically. This function is const, even though it changes the object, because generally fiddling with an object's reference count isn't considered part of fiddling with the object. An object might be const in other ways, but we still need to accurately count the number of references to it.

testRefCountIntegrity bool ReferenceCount::test_ref_count_integrity(void) const; Description: Does some easy checks to make sure that the reference count isn't completely bogus. Returns true if ok, false otherwise.

testRefCountNonzero bool ReferenceCount::test_ref_count_nonzero(void) const; Description: Does some easy checks to make sure that the reference count isn't zero, or completely bogus. Returns true if ok, false otherwise.

unref bool ReferenceCount::unref(void) const; Description: Explicitly decrements the reference count. Note that the object will not be implicitly deleted by unref() simply because the reference count drops to zero. (Having a member function delete itself is problematic; plus, we don't have a virtual destructor anyway.) However, see the helper function unref_delete(). User code should avoid using ref() and unref() directly, which can result in missed reference counts. Instead, let a PointerTo object manage the reference counting automatically. This function is const, even though it changes the object, because generally fiddling with an object's reference count isn't considered part of fiddling with the object. An object might be const in other ways, but we still need to accurately count the number of references to it. The return value is true if the new reference count is nonzero, false if it is zero.