# GeomNode¶

class GeomNode

Bases: PandaNode

A node that holds Geom objects, renderable pieces of geometry. This is the primary kind of leaf node in the scene graph; almost all visible objects will be contained in a GeomNode somewhere.

Inheritance diagram

explicit GeomNode(std::string const &name)
void add_geom(Geom *geom, RenderState const *state = RenderState::make_empty())

Adds a new Geom to the node. The geom is given the indicated state (which may be RenderState::make_empty(), to completely inherit its state from the scene graph).

void add_geoms_from(GeomNode const *other)

Copies the Geoms (and their associated RenderStates) from the indicated GeomNode into this one.

bool check_valid(void) const

Verifies that the each Geom within the GeomNode reference vertices that actually exist within its GeomVertexData. Returns true if the GeomNode appears to be valid, false otherwise.

void decompose(void)

Calls decompose() on each Geom with the GeomNode. This decomposes higher- order primitive types, like triangle strips, into lower-order types like indexed triangles. Normally there is no reason to do this, but it can be useful as an early preprocessing step, to allow a later call to unify() to proceed more quickly.

See also SceneGraphReducer::decompose(), which is the normal way this is called.

static TypeHandle get_class_type(void)
CollideMask get_default_collide_mask(void)

Returns the default into_collide_mask assigned to new GeomNodes.

ConstPointerTo<Geom> get_geom(int n) const

Returns the nth geom of the node. This object should not be modified, since the same object might be shared between multiple different GeomNodes, but see modify_geom().

RenderState const *get_geom_state(int n) const

Returns the RenderState associated with the nth geom of the node. This is just the RenderState directly associated with the Geom; the actual state in which the Geom is rendered will also be affected by RenderStates that appear on the scene graph in nodes above this GeomNode.

int get_num_geoms(void) const

Returns the number of geoms in the node.

bool get_preserved(void) const

Returns the “preserved” flag. When this is true, the GeomNode will be left untouched by any flatten operations.

PointerTo<Geom> modify_geom(int n)

Returns the nth geom of the node, suitable for modifying it. If the nth Geom has multiple reference counts to it, reassigns it to an identical copy first, and returns the new copy–this provides a “copy on write” that ensures that the Geom that is returned is unique to this GeomNode and is not shared with any other GeomNodes.

Note that if this method is called in a downstream stage (for instance, during cull or draw), then it will propagate the new list of Geoms upstream all the way to pipeline stage 0, which may step on changes that were made independently in pipeline stage 0. Use with caution.

void remove_all_geoms(void)

Removes all the geoms from the node at once.

void remove_geom(int n)

Removes the nth geom from the node.

void set_geom(int n, Geom *geom)

Replaces the nth Geom of the node with a new pointer. There must already be a Geom in this slot.

Note that if this method is called in a downstream stage (for instance, during cull or draw), then it will propagate the new list of Geoms upstream all the way to pipeline stage 0, which may step on changes that were made independently in pipeline stage 0. Use with caution.

void set_geom_state(int n, RenderState const *state)

Changes the RenderState associated with the nth geom of the node. This is just the RenderState directly associated with the Geom; the actual state in which the Geom is rendered will also be affected by RenderStates that appear on the scene graph in nodes above this GeomNode.

Note that if this method is called in a downstream stage (for instance, during cull or draw), then it will propagate the new list of Geoms upstream all the way to pipeline stage 0, which may step on changes that were made independently in pipeline stage 0. Use with caution.

void set_preserved(bool value)

Sets the “preserved” flag. When this is true, the GeomNode will be left untouched by any flatten operations.

void unify(int max_indices, bool preserve_order)

Attempts to unify all of the Geoms contained within this node into a single Geom, or at least as few Geoms as possible. In turn, the individual GeomPrimitives contained within each resulting Geom are also unified. The goal is to reduce the number of GeomPrimitives within the node as far as possible. This may result in composite primitives, such as triangle strips and triangle fans, being decomposed into triangles. See also Geom::unify().

max_indices represents the maximum number of indices that will be put in any one GeomPrimitive. If preserve_order is true, then the primitives will not be reordered during the operation, even if this results in a suboptimal result.

In order for this to be successful, the primitives must reference the same GeomVertexData, have the same fundamental primitive type, and have compatible shade models.

void write_geoms(std::ostream &out, int indent_level) const

Writes a short description of all the Geoms in the node.

void write_verbose(std::ostream &out, int indent_level) const

Writes a detailed description of all the Geoms in the node.