Panda3D
Public Types | Public Member Functions | Static Public Member Functions | Public Attributes | List of all members
RenderAttrib Class Reference

This is the base class for a number of render attributes (other than transform) that may be set on scene graph nodes to control the appearance of geometry. More...

Inheritance diagram for RenderAttrib:
TypedWritableReferenceCount TypedWritable ReferenceCount TypedObject AlphaTestAttrib AntialiasAttrib AudioVolumeAttrib AuxBitplaneAttrib ClipPlaneAttrib ColorAttrib ColorBlendAttrib ColorScaleAttrib ColorWriteAttrib CullBinAttrib CullFaceAttrib DepthOffsetAttrib DepthTestAttrib DepthWriteAttrib FogAttrib LightAttrib LightRampAttrib LogicOpAttrib MaterialAttrib RenderModeAttrib RescaleNormalAttrib ScissorAttrib ShadeModelAttrib ShaderAttrib StencilAttrib TexGenAttrib TexMatrixAttrib TextureAttrib TransparencyAttrib

Public Types

enum  PandaCompareFunc {
  M_none = 0, M_never = 1, M_less = 2, M_equal = 3,
  M_less_equal = 4, M_greater = 5, M_not_equal = 6, M_greater_equal = 7,
  M_always = 8
}
 
enum  TexGenMode {
  M_off = 0, M_eye_sphere_map = 1, M_world_cube_map = 2, M_eye_cube_map = 3,
  M_world_normal = 4, M_eye_normal = 5, M_world_position = 6, M_unused = 7,
  M_eye_position = 8, M_point_sprite = 9, M_unused2 = 10, M_constant = 11
}
 

Public Member Functions

int compareTo (const RenderAttrib other)
 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. More...
 
const RenderAttrib compose (const RenderAttrib other)
 Returns a new RenderAttrib object that represents the composition of this attrib with the other attrib. More...
 
int getHash ()
 Returns a suitable hash value for phash_map. More...
 
int getSlot ()
 
const RenderAttrib getUnique ()
 Returns the pointer to the unique RenderAttrib in the cache that is equivalent to this one. More...
 
const RenderAttrib invertCompose (const RenderAttrib other)
 Returns a new RenderAttrib object that represents the composition of the inverse of this attrib with the other attrib. More...
 
bool lowerAttribCanOverride ()
 Intended to be overridden by derived RenderAttrib types to specify how two consecutive RenderAttrib objects of the same type interact. More...
 
 output (Ostream out)
 
 write (Ostream out, int indent_level)
 
- Public Member Functions inherited from TypedWritable
object __reduce__ ()
 
object __reduce_persist__ (object pickler)
 
VectorUchar encodeToBamStream ()
 Converts the TypedWritable object into a single stream of data using a BamWriter, and returns that data as a bytes object. More...
 
bool encodeToBamStream (VectorUchar data, BamWriter writer)
 Converts the TypedWritable object into a single stream of data using a BamWriter, and stores that data in the indicated string. More...
 
 fillin (DatagramIterator scan, BamReader manager)
 This internal function is intended to be called by each class's make_from_bam() method to read in all of the relevant data from the BamFile for the new object. More...
 
UpdateSeq getBamModified ()
 Returns the current bam_modified counter. More...
 
 markBamModified ()
 Increments the bam_modified counter, so that this object will be invalidated and retransmitted on any open bam streams. More...
 
- Public Member Functions inherited from TypedObject
TypeHandle getType ()
 
int getTypeIndex ()
 Returns the internal index number associated with this object's TypeHandle, a unique number for each different type. More...
 
bool isExactType (TypeHandle handle)
 Returns true if the current object is the indicated type exactly. More...
 
bool isOfType (TypeHandle handle)
 Returns true if the current object is or derives from the indicated type. More...
 
- Public Member Functions inherited from ReferenceCount
int getRefCount ()
 Returns the current reference count. More...
 
 ref ()
 Explicitly increments the reference count. More...
 
bool testRefCountIntegrity ()
 Does some easy checks to make sure that the reference count isn't completely bogus. More...
 
bool testRefCountNonzero ()
 Does some easy checks to make sure that the reference count isn't zero, or completely bogus. More...
 
bool unref ()
 Explicitly decrements the reference count. More...
 

Static Public Member Functions

static int garbageCollect ()
 Performs a garbage-collection cycle. More...
 
static TypeHandle getClassType ()
 
static int getNumAttribs ()
 Returns the total number of unique RenderAttrib objects allocated in the world. More...
 
static listAttribs (Ostream out)
 Lists all of the RenderAttribs in the cache to the output stream, one per line. More...
 
static bool validateAttribs ()
 Ensures that the cache is still stored in sorted order. More...
 
- Static Public Member Functions inherited from TypedWritableReferenceCount
static TypedWritableReferenceCount decodeFromBamStream (VectorUchar data, BamReader reader)
 Reads the bytes created by a previous call to encode_to_bam_stream(), and extracts and returns the single object on those bytes. More...
 
static TypeHandle getClassType ()
 
- Static Public Member Functions inherited from TypedWritable
static TypeHandle getClassType ()
 
- Static Public Member Functions inherited from TypedObject
static TypeHandle getClassType ()
 
- Static Public Member Functions inherited from ReferenceCount
static TypeHandle getClassType ()
 

Public Attributes

int slot
 
- Public Attributes inherited from TypedObject
TypeHandle type
 Returns the TypeHandle representing this object's type. More...
 
- Public Attributes inherited from ReferenceCount
int ref_count
 The current reference count. More...
 

Detailed Description

This is the base class for a number of render attributes (other than transform) that may be set on scene graph nodes to control the appearance of geometry.

This includes TextureAttrib, ColorAttrib, etc.

RenderAttrib represents render attributes that always propagate down to the leaves without regard to the particular node they are assigned to. A RenderAttrib will have the same effect on a leaf node whether it is assigned to the graph at the leaf or several nodes above. This is different from RenderEffect, which represents a particular render property that is applied immediately to the node on which it is encountered, like billboarding or decaling.

You should not attempt to create or modify a RenderAttrib directly; instead, use the make() method of the appropriate kind of attrib you want. This will allocate and return a new RenderAttrib of the appropriate type, and it may share pointers if possible. Do not modify the new RenderAttrib if you wish to change its properties; instead, create a new one.

Member Enumeration Documentation

◆ PandaCompareFunc

Enumerator
M_none 

alpha-test disabled (always-draw)

M_never 

Never draw.

M_less 

incoming < reference_alpha

M_equal 

incoming == reference_alpha

M_less_equal 

incoming <= reference_alpha

M_greater 

incoming > reference_alpha

M_not_equal 

incoming != reference_alpha

M_greater_equal 

incoming >= reference_alpha

M_always 

Always draw.

◆ TexGenMode

enum TexGenMode
Enumerator
M_off 
M_eye_sphere_map 

Sphere maps are classic static reflection maps. They are supported on just about any hardware, and require a precomputed 360-degree fisheye image. Sphere maps only make sense in eye coordinate space.

M_world_cube_map 
  • Cube maps are a modern improvement on the sphere map; they don't suffer
  • from any polar singularities, but they require six texture images. They
  • can also be generated dynamically for real-time reflections (see
  • GraphicsOutput::make_cube_map()). Typically, a statically-generated cube
  • map will be in eye space, while a dynamically-generated map will be in
  • world space. Cube mapping is not supported on all hardware.
M_eye_cube_map 
M_world_normal 

Normal maps are most useful for applying diffuse lighting effects via a pregenerated cube map.

M_eye_normal 
M_world_position 

Position maps convert XYZ coordinates directly to texture coordinates. This is particularly useful for implementing projective texturing (see NodePath::project_texture()).

M_unused 

formerly M_object_position, now deprecated.

M_eye_position 
M_point_sprite 
  • With M_point_sprite, texture coordinates will be generated for large points
  • in the range (0,0) - (1,1) from upper-left to lower-right across the
  • point's face. Without this, each point will have just a single uniform
  • texture coordinate value across its face. Unfortunately, the generated
  • texture coordinates are inverted (upside-down) from Panda's usual
  • convention, but this is what the graphics card manufacturers decided to
  • use. You could use a texture matrix to re-invert the texture, but that
  • will probably force the sprites' vertices to be computed in the CPU. You'll
  • have to paint your textures upside-down if you want true hardware sprites.
M_unused2 

M_light_vector generated special 3-d texture coordinates that represented the vector to a particular Light in the scene graph, expressed in each vertex's tangent space. This has now been removed. We need to reserve the slot in the enum, though, to make sure the following enum value still has the same value.

M_constant 

M_constant generates the same fixed texture coordinates at each vertex. Not terribly useful, of course, except for certain special effects involving moving a flat color over an object.

Member Function Documentation

◆ compareTo()

int compareTo ( const RenderAttrib  other)

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.

◆ compose()

const RenderAttrib compose ( const RenderAttrib  other)

Returns a new RenderAttrib object that represents the composition of this attrib with the other attrib.

In most cases, this is the same as the other attrib; a compose b produces b. Some kinds of attributes, like a TextureTransform, for instance, might produce a new result: a compose b produces c.

◆ garbageCollect()

static int garbageCollect ( )
static

Performs a garbage-collection cycle.

This is called automatically from RenderState::garbage_collect(); see that method for more information.

◆ getClassType()

static TypeHandle getClassType ( )
static

◆ getHash()

int getHash ( )

Returns a suitable hash value for phash_map.

◆ getNumAttribs()

static int getNumAttribs ( )
static

Returns the total number of unique RenderAttrib objects allocated in the world.

This will go up and down during normal operations.

◆ getSlot()

int getSlot ( )

◆ getUnique()

const RenderAttrib getUnique ( )

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.

◆ invertCompose()

const RenderAttrib invertCompose ( const RenderAttrib  other)

Returns a new RenderAttrib object that represents the composition of the inverse of this attrib with the other attrib.

In most cases, this is the same as the other attrib; !a compose b produces b. Some kinds of attributes, like a TextureTransform, for instance, might produce a new result: !a compose b produces c.

This is similar to compose() except that the source attrib is inverted first. This is used to compute the relative attribute for one node as viewed from some other node, which is especially useful for transform-type attributes.

◆ listAttribs()

static listAttribs ( Ostream  out)
static

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.

◆ lowerAttribCanOverride()

bool lowerAttribCanOverride ( )

Intended to be overridden by derived RenderAttrib types to specify how two consecutive RenderAttrib objects of the same type interact.

This should return false if a RenderAttrib on a higher node will compose into a RenderAttrib on a lower node that has a higher override value, or true if the lower RenderAttrib will completely replace the state.

The default behavior is false: normally, a RenderAttrib in the graph cannot completely override a RenderAttrib above it, regardless of its override value–instead, the two attribs are composed. But for some kinds of RenderAttribs, it is useful to allow this kind of override.

This method only handles the one special case of a lower RenderAttrib with a higher override value. If the higher RenderAttrib has a higher override value, it always completely overrides. And if both RenderAttribs have the same override value, they are always composed.

◆ output()

output ( Ostream  out)

◆ validateAttribs()

static bool validateAttribs ( )
static

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()

write ( Ostream  out,
int  indent_level 
)

Member Data Documentation

◆ slot

int slot