Graph View Data Format (XPresso) Manual

Currently there are two ways to store data of variable type. The first one is GeData, the class that is used in most of the SDK for example in BaseContainer. The second one is the void* data that is used in Graph View. This document describes how the Graph View data type system works.

Note: Types registered with CustomDataTypeClass are automatically included in the Graph View type system as well.

Value vs. Data

The actual format of the data stored in the void* pointer is determined by its value, described by a GvValueID. This is all you need to know to be able to perform calculations with the data or convert it to other types.

Similar kinds of data can share a common value. The combination of a symbol/name and a value is called a data, described by a GvDataID. For example both the normal and the color data types could be implemented as a vector value.

The different data types are grouped in value groups. However, currently there is only one group, so you can ignore this feature most of the time.

FindCustomDataTypePlugin() will always return a valid plugin when fed a GvValueID. You cannot convert a GvValueID to a GvDataID directly, though you can do CallCustomDataType(pl, GetDataID).

Raw Format

For the common built-in types (Int32, Float, Vector, Matrix, BaseTime and String) the void* pointer simply points to the data type in question. For custom data types it instead points to the GvHelper structure. Please observe that generally these pointers are to an array that you should index with the current CPU ID.

Normally you should not need to manipulate these raw values.

Dynamic Data

GvDynamicData is a convenience structure that stores both the void* data pointer and a GvDataInfo structure with the handlers. There are several ways to get a dynamic data structure:

Many of these functions are implemented in clear code in c4d_graphview.h and c4d_graphview.cpp, so you can see how they work.


Getting a GeData from a calculated port:

GeData GvGetPortGeData(GvNode* node, GvPort* port, GvRun* run, Bool* success)
if (success)
*success = false;
if (!node || !port)
return GeData();
if (!node->GetPortDescription(port->GetIO(), port->GetMainID(), &pd))
return GeData();
if (!info) return GeData();
if (port->GetData(,>value_handler->value_id, run))
CUSTOMDATATYPEPLUGIN* pl = FindCustomDataTypePlugin(>data_handler->data_id);
if (pl && CallCustomDataType(pl, ConvertGvToGeData)(, 0, result))
if (success)
*success = true;
return result;
CUSTOMDATATYPEPLUGIN * FindCustomDataTypePlugin(Int32 type)
Definition: c4d_gedata.h:83
Definition: c4d_graphview.h:429
Definition: c4d_graphview.h:938
Int32 GetMainID(void)
Definition: c4d_graphview.h:1006
Bool GetData(void *d, GvValueID type, GvRun *r)
Definition: c4d_graphview.h:1177
GvPortIO GetIO(void)
Definition: c4d_graphview.h:994
Contains helper functions for controlling node evaluation. Cannot be instantiated.
Definition: c4d_graphview.h:314
GvDataInfo * GetDataTypeInfo(GvDataID id)
Definition: c4d_graphview.h:2386
PyObject PyObject * result
Definition: abstract.h:43
maxon::Bool Bool
Definition: ge_sys_math.h:55
Bool GvAllocDynamicData(GvNode *bn, GvDynamicData &data, GvCalc *c, Int32 id)
Definition: c4d_graphview.h:2697
GvWorld * GvGetWorld(void)
void GvFreeDynamicData(GvDynamicData &data)
Definition: c4d_graphview.h:2708
_Py_clock_info_t * info
Definition: pytime.h:197
Definition: node.h:10
GvDataID data_id
The data ID.
Definition: c4d_graphview_def.h:1031
GvValueID value_id
Value ID.
Definition: c4d_graphview_def.h:875
Definition: c4d_graphview_def.h:1091
GV_VALUE_HANDLER * value_handler
Definition: c4d_graphview_def.h:1093
GV_DATA_HANDLER * data_handler
Definition: c4d_graphview_def.h:1092
Represents a GV data and information about its data type.
Definition: c4d_graphview_def.h:1260
void * data
Data pointer.
Definition: c4d_graphview_def.h:1266
GvDataInfo * info
Data type information.
Definition: c4d_graphview_def.h:1267
Port description data.
Definition: c4d_graphview_def.h:1162
GvDataID data_id
Data type ID: GvDataID.
Definition: c4d_graphview_def.h:1170

Setting the port data from a GeData:

Bool GvSetPortGeData(const GeData& ge_data, GvNode* node, GvPort* port, GvRun* run)
if (!node || !port || !run)
return false;
if (!node->GetPortDescription(port->GetIO(), port->GetMainID(), &pd))
return false;
if (info==nullptr)
return false;
CUSTOMDATATYPEPLUGIN* pl = FindCustomDataTypePlugin(>data_handler->data_id);
if (pl==nullptr)
return false;
if (!CallCustomDataType(pl, ConvertGeDataToGv)(ge_data,, 0))
return false;
if (!port->SetData(,>value_handler->value_id, run))
return false
return true;
Bool SetData(const void *d, GvValueID type, GvRun *r)
Definition: c4d_graphview.h:1274

Getting a Thinking Particles particle ID from a port:

Int32 GvGetParticleID(GvNode* node, GvPort* port, GvRun* run)
if (!port || !node || !run) return NOTOK;
GeData p = GvGetPortGeData(node, port, run);
if (p.GetType() != ID_TP_DATA_TYPE_PARTICLE) return NOTOK;
struct GvParticleHelper : public CustomDataType
Int32* pid;
}* helper = static_cast<GvParticleHelper*>(p.GetCustomDataType(ID_TP_DATA_TYPE_PARTICLE));
if (!helper || !helper->pid) return NOTOK;
return *(helper->pid);
Setting a Thinking Particles particle ID in a port:
Bool GvSetParticleID(Int32 pid, GvNode* node, GvPort* port, GvRun* run)
if (!port || !node || !run) return NOTOK;
struct GvParticleHelper : public CustomDataType
Int32* pid;
} helper; = &pid;
return GvSetPortGeData(p, node, port, run);
Particle data type ID.
Definition: c4d_particles.h:31
unsigned char * p
Definition: floatobject.h:87
#define NOTOK
Definition: ge_sys_math.h:267
maxon::Int32 Int32
Definition: ge_sys_math.h:60
Base class for custom data types.
Definition: c4d_customdatatype.h:51