panda3d.core.GeomVertexColumn

from panda3d.core import GeomVertexColumn
class GeomVertexColumn

Bases: GeomEnums

This defines how a single column is interleaved within a vertex array stored within a Geom. The GeomVertexArrayFormat class maintains a list of these to completely define a particular array structure.

Inheritance diagram

Inheritance diagram of GeomVertexColumn

__init__(name: InternalName, num_components: int, numeric_type: NumericType, contents: Contents, start: int, column_alignment: int, num_elements: int, element_stride: int) → None
__init__(copy: GeomVertexColumn) → None
assign(copy: GeomVertexColumn) → GeomVertexColumn
Return type

GeomVertexColumn

getName() → InternalName

Returns the name of this particular data field, e.g. “vertex” or “normal”. The name may be a user-defined string, or it may be one of the standard system-defined field types. Only the system-defined field types are used for the actual rendering.

Return type

InternalName

getNumComponents() → int

Returns the number of components of the column: the number of instances of the NumericType in each element. This is usually, but not always, the same thing as getNumValues().

getNumValues() → int

Returns the number of numeric values of the column: the number of distinct numeric values that go into each element. This is usually, but not always, the same thing as getNumComponents(); the difference is in the case of a composite numeric type like NT_packed_dcba, which has four numeric values per component.

getNumElements() → int

Returns the number of times this column is repeated. This is usually 1, except for matrices.

getNumericType() → NumericType

Returns the token representing the numeric type of the data storage.

Return type

NumericType

getContents() → Contents

Returns the token representing the semantic meaning of the stored value.

Return type

Contents

getStart() → int

Returns the byte within the array record at which this column starts. This can be set to non-zero to implement interleaved arrays.

getColumnAlignment() → int

Returns the alignment requirements for this column. If this is greater than 1, it restricts the column to appear only on memory addresses that are integer multiples of this value; this has implications for this column’s start value, as well as the stride of the resulting array.

getElementStride() → int

This value is only relevant for matrix types. Returns the number of bytes to add to access the next row of the matrix.

getComponentBytes() → int

Returns the number of bytes used by each component (that is, by one element of the numeric type).

getTotalBytes() → int

Returns the number of bytes used by each element of the column: component_bytes * num_components.

hasHomogeneousCoord() → bool

Returns true if this Contents type is one that includes a homogeneous coordinate in the fourth component, or false otherwise. If this is true, correct operation on the vertex data may require scaling by the homogeneous coordinate from time to time (but in general this is handled automatically if you use the 3-component or smaller forms of get_data() and set_data()).

overlapsWith(start_byte: int, num_bytes: int) → bool

Returns true if this column overlaps with any of the bytes in the indicated range, false if it does not.

isBytewiseEquivalent(other: GeomVertexColumn) → bool

Returns true if the data store of this column is exactly the same as that of the other, irrespective of name or start position within the record.

setName(name: InternalName) → None

Replaces the name of an existing column. This is only legal on an unregistered format (i.e. when constructing the format initially).

setNumComponents(num_components: int) → None

Changes the number of components of an existing column. This is only legal on an unregistered format (i.e. when constructing the format initially).

setNumericType(numeric_type: NumericType) → None

Changes the numeric type an existing column. This is only legal on an unregistered format (i.e. when constructing the format initially).

setContents(contents: Contents) → None

Changes the semantic meaning of an existing column. This is only legal on an unregistered format (i.e. when constructing the format initially).

setStart(start: int) → None

Changes the start byte of an existing column. This is only legal on an unregistered format (i.e. when constructing the format initially).

setColumnAlignment(column_alignment: int) → None

Changes the column alignment of an existing column. This is only legal on an unregistered format (i.e. when constructing the format initially).

output(out: ostream) → None