panda3d.core.GeomVertexArrayFormat

class GeomVertexArrayFormat

Bases: TypedWritableReferenceCount, GeomEnums

This describes the structure of a single array within a Geom data. See GeomVertexFormat for the parent class which collects together all of the individual GeomVertexArrayFormat objects.

A particular array may include any number of standard or user-defined columns. All columns consist of a sequence of one or more numeric values, packed in any of a variety of formats; the semantic meaning of each column is defined in general with its contents member, and in particular by its name. The standard array types used most often are named “vertex”, “normal”, “texcoord”, and “color”; other kinds of data may be piggybacked into the data record simply by choosing a unique name.

Inheritance diagram

Inheritance diagram of GeomVertexArrayFormat

__init__() → None
__init__(name0: InternalName, num_components0: int, numeric_type0: NumericType, contents0: Contents) → None
__init__(name0: InternalName, num_components0: int, numeric_type0: NumericType, contents0: Contents, name1: InternalName, num_components1: int, numeric_type1: NumericType, contents1: Contents) → None
__init__(name0: InternalName, num_components0: int, numeric_type0: NumericType, contents0: Contents, name1: InternalName, num_components1: int, numeric_type1: NumericType, contents1: Contents, name2: InternalName, num_components2: int, numeric_type2: NumericType, contents2: Contents) → None
__init__(name0: InternalName, num_components0: int, numeric_type0: NumericType, contents0: Contents, name1: InternalName, num_components1: int, numeric_type1: NumericType, contents1: Contents, name2: InternalName, num_components2: int, numeric_type2: NumericType, contents2: Contents, name3: InternalName, num_components3: int, numeric_type3: NumericType, contents3: Contents) → None
__init__(copy: GeomVertexArrayFormat) → None
addColumn(name: InternalName, num_components: int, numeric_type: NumericType, contents: Contents, start: int, column_alignment: int) → int

Adds a new column to the specification. This is a table of per-vertex floating-point numbers such as “vertex” or “normal”; you must specify where in each record the table starts, and how many components (dimensions) exist per vertex.

The return value is the index number of the new data type.

addColumn(column: GeomVertexColumn) → int

Adds a new column to the specification. This is a table of per-vertex floating-point numbers such as “vertex” or “normal”; you must specify where in each record the table starts, and how many components (dimensions) exist per vertex.

Adding a column with the same name as a previous type, or that overlaps with one or more previous types, quietly removes the previous type(s).

The return value is the index number of the new data type.

alignColumnsForAnimation() → None

Reprocesses the columns in the format to align the C_point and C_vector columns to 16-byte boundaries to allow for the more efficient SSE2 operations (assuming SSE2 is enabled in the build).

The caller is responsible for testing vertex_animation_align_16 to decide whether to call this method.

assign(copy: GeomVertexArrayFormat) → GeomVertexArrayFormat
Return type

GeomVertexArrayFormat

clearColumns() → None

Removes all columns previously added, sets the stride to zero, and prepares to start over.

property columns

Returns the ith column of the array.

Returns the specification with the indicated name, or NULL if the name is not used.

Returns the first specification that overlaps with any of the indicated bytes in the range, or NULL if none do.

Return type

Sequence[GeomVertexColumn]

countUnusedSpace() → int

Returns the number of bytes per row that are not assigned to any column.

property divisor
Getter

Returns the divisor attribute for the data in this array. If 0, it contains per-vertex data. If 1, it contains per-instance data. If higher than 1, the read row is advanced for each n instances.

Setter

Set this to 0 to indicate that this array contains per-vertex data, or to 1 to indicate that it contains per-instance data. If higher than 1, the read row is advanced for each n instances.

Return type

int

static getClassType() → TypeHandle
Return type

TypeHandle

getColumn(name: InternalName) → GeomVertexColumn

Returns the specification with the indicated name, or NULL if the name is not used.

Return type

GeomVertexColumn

getColumn(i: int) → GeomVertexColumn

Returns the ith column of the array.

Return type

GeomVertexColumn

getColumn(start_byte: int, num_bytes: int) → GeomVertexColumn

Returns the first specification that overlaps with any of the indicated bytes in the range, or NULL if none do.

Return type

GeomVertexColumn

getColumns() → list
getDivisor() → int

Returns the divisor attribute for the data in this array. If 0, it contains per-vertex data. If 1, it contains per-instance data. If higher than 1, the read row is advanced for each n instances.

getFormatString(pad: bool) → str

Returns a string with format codes representing the exact memory layout of the columns in memory, as understood by Python’s struct module. If pad is true, extra padding bytes are added to the end as ‘x’ characters as needed.

getNumColumns() → int

Returns the number of different columns in the array.

getPadTo() → int

Returns the byte divisor to which the data record must be padded to meet hardware limitations. For instance, if this is 4, the stride will be automatically rounded up to the next multiple of 4 bytes. This value is automatically increased as needed to ensure the individual numeric components in the array are word-aligned.

getStride() → int

Returns the total number of bytes reserved in the array for each vertex.

getTotalBytes() → int

Returns the total number of bytes used by the data types within the format, including gaps between elements.

hasColumn(name: InternalName) → bool

Returns true if the array has the named column, false otherwise.

isDataSubsetOf(other: GeomVertexArrayFormat) → bool

Returns true if all of the fields in this array format are also present and equivalent in the other array format, and in the same byte positions, and the stride is the same. That is, true if this format can share the same data pointer as the other format (with possibly some unused gaps).

isRegistered() → bool

Returns true if this format has been registered, false if it has not. It may not be used for a Geom until it has been registered, but once registered, it may no longer be modified.

output(out: ostream) → None
packColumns() → None

Removes wasted space between columns.

property pad_to
Getter

Returns the byte divisor to which the data record must be padded to meet hardware limitations. For instance, if this is 4, the stride will be automatically rounded up to the next multiple of 4 bytes. This value is automatically increased as needed to ensure the individual numeric components in the array are word-aligned.

Setter

Explicitly sets the byte divisor to which the data record must be padded to meet hardware limitations. See getPadTo(). Normally it is not necessary to call this unless you have some specific requirements for row-to-row data alignment. Note that this value may be automatically increased at each subsequent call to addColumn().

Return type

int

static registerFormat(format: GeomVertexArrayFormat) → GeomVertexArrayFormat

Adds the indicated format to the registry, if there is not an equivalent format already there; in either case, returns the pointer to the equivalent format now in the registry.

This is similar to GeomVertexFormat.registerFormat(), except that you generally need not call it explicitly. Calling GeomVertexFormat.registerFormat() automatically registers all of the nested array formats.

Return type

GeomVertexArrayFormat

property registered

Returns true if this format has been registered, false if it has not. It may not be used for a Geom until it has been registered, but once registered, it may no longer be modified.

Return type

bool

removeColumn(name: InternalName) → None

Removes the column with the indicated name, if any. This leaves a gap in the byte structure.

setDivisor(divisor: int) → None

Set this to 0 to indicate that this array contains per-vertex data, or to 1 to indicate that it contains per-instance data. If higher than 1, the read row is advanced for each n instances.

setPadTo(pad_to: int) → None

Explicitly sets the byte divisor to which the data record must be padded to meet hardware limitations. See getPadTo(). Normally it is not necessary to call this unless you have some specific requirements for row-to-row data alignment. Note that this value may be automatically increased at each subsequent call to addColumn().

setStride(stride: int) → None

Changes the total number of bytes reserved in the array for each vertex. You may not reduce this below getTotalBytes(), but you may increase it arbitrarily.

property stride
Getter

Returns the total number of bytes reserved in the array for each vertex.

Setter

Changes the total number of bytes reserved in the array for each vertex. You may not reduce this below getTotalBytes(), but you may increase it arbitrarily.

Return type

int

property total_bytes

Returns the total number of bytes used by the data types within the format, including gaps between elements.

Return type

int

unref() → bool

This method overrides ReferenceCount.unref() to unregister the object when its reference count goes to zero.

write(out: ostream, indent_level: int) → None
writeWithData(out: ostream, indent_level: int, array_data: GeomVertexArrayData) → None