CRenderHairAccessor Class
Reference
#include <xsi_renderhairaccessor.h>
This class provides access to the render hair information exposed by the hair primitive. This information includes: the vertex positions of each generated render hair, the root/tip radius values, the UVW, weight map and vertex color values for each render hair root location.
CRenderHairAccessor provides a mechanism to access the data in chunks which allows you to optimize the memory allocation required for accessing such a large data set.
Use HairPrimitive::GetRenderHairAccessor to create an instance of CRenderHairAccessor.
using namespace XSI;
Application app;
Model root = app.GetActiveSceneRoot();
// create a cone with hair along with a uv property
X3DObject myCone;
root.AddGeometry( L"Cone", L"MeshSurface",L"myCone",myCone);
Material myMat;
myCone.AddMaterial(L"Phong", false, L"myMat", myMat);
Shader sh = myMat.GetShaders().GetItem(0);
Parameter p = sh.GetParameters().GetItem(L"diffuse");
// connect an image parameter and add a UV property on the diffuse param
CRef newSource;
CRef prevSource;
p.ConnectFromPreset( L"Image", siTextureShaderFamily, prevSource, newSource );
// creates a projection i.e. UV property
CValueArray args(7);
CValue outArg;
args[0] = myCone.GetFullName();
args[1] = CString(L"siTxtSpherical");
args[2] = CString(L"siTxtDefaultSpherical");
args[3] = CValue();
args[4] = CString(L"Texture_Projection");
args[5] = CValue();
args[6] = CValue((LONG)XSI::siRelDefault);
app.ExecuteCommand( L"CreateProjection", args, outArg );
// assign the projection to the cone
args.Resize(3);
args[0] = myCone.GetFullName();
args[1] = CString(L"Sources.Materials.DefaultLib.myMat.Phong.Image.tspace_id");
args[2] = CString(L"Texture_Projection");
app.ExecuteCommand( L"SetInstanceDataValue", args, outArg );
// add hair to the cone
args.Resize(1);
args[0] = myCone;
app.ExecuteCommand( L"ApplyHairOp", args, outArg ) ;
// transfer the uv property to the hair primitive
X3DObject myHair = myCone.FindChild( L"Hair", L"", CStringArray() );
args.Resize(2);
args[0] = myHair.GetFullName();
args[1] = CString(L"myCone.polymsh.cls.Texture_Coordinates_AUTO.Texture_Projection");
app.ExecuteCommand( L"PropertyTransfer", args, outArg ) ;
// setup a render hair accessor for 100 hairs with a chunk size of 10
HairPrimitive myHairPrim( myHair.GetActivePrimitive() );
CRenderHairAccessor rha = myHairPrim.GetRenderHairAccessor( 100, 10 );
LONG nReqChunkSize = rha.GetRequestedChunkSize();
app.LogMessage( L"nReqChunkSize: " + CValue(nReqChunkSize).GetAsText() );
LONG nReqHairCount = rha.GetRequestedHairCount();
app.LogMessage( L"nReqHairCount: " + CValue(nReqHairCount).GetAsText() );
LONG nUVs = rha.GetUVCount();
app.LogMessage( L"nUVs: " + CValue(nUVs).GetAsText() );
// get the values in chunks
LONG nChunk = 0;
LONG i=0;
while( rha.Next() )
{
app.LogMessage( L"Chunk: " + CValue(nChunk++).GetAsText() );
// get the number of vertices for each render hair
// note: this array is used for iterating over the render hair position
// and radius values
CLongArray verticesCountArray;
rha.GetVerticesCount(verticesCountArray);
// get the render hair positions
CFloatArray posVals;
rha.GetVertexPositions(posVals);
LONG k = 0;
app.LogMessage( L"Render hair position values: " );
for (i=0; i<verticesCountArray.GetCount(); i++ )
{
LONG nCount = verticesCountArray[i];
for (LONG j=0; j<nCount; j++ )
{
CString strVals;
strVals=
CValue(posVals[k++]).GetAsText() + CString(L" ") +
CValue(posVals[k++]).GetAsText() + CString(L" ") +
CValue(posVals[k++]).GetAsText() ;
app.LogMessage( CValue(i).GetAsText() + L": " + strVals );
}
}
// get the render hair radius
app.LogMessage( L"Render hair radius values: " );
CFloatArray radVals;
rha.GetVertexRadiusValues(radVals);
k = 0;
for (i=0; i<verticesCountArray.GetCount(); i++ )
{
LONG nCount = verticesCountArray[i];
for (LONG j=0; j<nCount; j++ )
{
app.LogMessage( CValue(i).GetAsText() + L": " +
CValue(radVals[k++]).GetAsText() );
}
}
// get the uv values
app.LogMessage( L"Render hair uv values: " );
for (i=0; i<nUVs; i++)
{
app.LogMessage( L" UV: " + rha.GetUVName(i) );
CFloatArray uvVals;
rha.GetUVValues( i, uvVals );
for (LONG j=0,k=0; j<uvVals.GetCount(); j+=3, k++)
{
CString strVals;
strVals =
CValue(uvVals[j+0]).GetAsText() + L" " +
CValue(uvVals[j+1]).GetAsText() + L" " +
CValue(uvVals[j+2]).GetAsText() ;
app.LogMessage( CValue(k).GetAsText() + L": " + strVals );
}
}
}
Default constructor.
| ~CRenderHairAccessor | ( | ) |
Default destructor.
| CRenderHairAccessor | ( | const CRef & | in_ref | ) |
Constructor.
| in_ref | constant reference object. |
| CRenderHairAccessor | ( | const CRenderHairAccessor & | in_obj | ) |
Copy constructor.
| in_obj | constant class object. |
| bool IsA | ( | siClassID | in_ClassID | ) | const [virtual] |
Returns true if a given class type is compatible with this API class.
| in_ClassID | class type. |
Reimplemented from CBase.
| siClassID GetClassID | ( | ) | const [virtual] |
| CRenderHairAccessor& operator= | ( | const CRenderHairAccessor & | in_obj | ) |
Creates an object from another object. The newly created object is set to empty if the input object is not compatible.
| in_obj | constant class object. |
| CRenderHairAccessor& operator= | ( | const CRef & | in_ref | ) |
Creates an object from a reference object. The newly created object is set to empty if the input reference object is not compatible.
| in_ref | constant class object. |
| bool Next | ( | ) |
Sets the accessor to the next available chunk of render hair data for reading. The position of the next chunk is computed based on the chunk size used for initializing the accessor. When the accessor is first initialized, there is no data available and CRenderHairAccessor::Next has to be called to receive the first chunk of data.
| CStatus Reset | ( | ) |
Sets the accessor to the first chunk of render hair data for reading.
| LONG GetRequestedChunkSize | ( | ) | const |
Returns the requested size of each render hair chunk. This number is always larger than or equal to the value returned from CRenderHairAccessor::GetChunkHairCount().
| LONG GetRequestedHairCount | ( | ) | const |
Returns the maximum number of render hairs to access. This value is specified when the accessor is first created and does not correspond to the maximum number of render hairs available on the primitive.
| LONG GetChunkHairCount | ( | ) | const |
Returns the number of render hairs available for the current chunk. If hairs have been trimmed due to cut or density maps, this number can be less than the requested chunk size, even zero.
| CStatus GetVerticesCount | ( | CLongArray & | out_values | ) | const |
Returns an array containing the number of vertices for each generated render hair. This array can be used to iterate over the array of vertices and radius values.
| out_values | Array of vertex count. |
| CStatus GetVertexPositions | ( | CFloatArray & | out_values | ) | const |
Returns an array of vertex positions (XYZ) for each render hair in local space. The vertex points are packed sequentially, the first being the root location, the next one in the sequence being the next connected point, all the way to the tip of the hair. Use the array returned by GetRenderHairAccessor::GetVerticesCount to find the number of vertices for each render hair in order to iterate over the vertex positions.
| out_values | XYZ values. |
| CStatus GetVertexRadiusValues | ( | CFloatArray & | out_values | ) | const |
Returns an array of radius values at each render hair vertex. The radius values are packed sequentially, the first being the radius of the root location, the next one in the sequence being the next connected point radius, all the way to the tip of the hair. Use the array returned by GetRenderHairAccessor::GetVerticesCount to find the number of vertices for each render hair in order to iterate over the vertex radius values.
| out_values | Radius values for each vertex of a render hair. |
| CStatus GetHairSurfaceNormalValues | ( | CFloatArray & | out_values | ) | const |
Returns the surface normal (XYZ) of the hair's emitter surface, from which each render hair is emitted.
| out_values | Surface normal values for each render hair. |
| LONG GetUVCount | ( | ) | const |
Returns the number of UV properties on the primitive.
| LONG GetVertexColorCount | ( | ) | const |
Returns the number of vertex color properties on the primitive.
| LONG GetWeightMapCount | ( | ) | const |
Returns the number of weight map properties on the primitive.
| CString GetUVName | ( | LONG | in_nIdx | ) | const |
| CString GetVertexColorName | ( | LONG | in_nIdx | ) | const |
Returns the name of the vertex color property at a given index. The index refers to the position of the property on the primitive.
| in_nIdx | Property index. |
| CString GetWeightMapName | ( | LONG | in_nIdx | ) | const |
| CStatus GetUVValues | ( | LONG | in_nIdx, |
| CFloatArray & | out_values | ||
| ) | const |
Returns an array of UVW values for the UV property at the specified index. The values match the render hair root locations on the primitive. The index refers to the position of the property on the primitive.
In general, the size of the returned array is GetRenderHairAccessor::GetChunkHairCount() * 3. However, in the case where render hairs are generated in an area where they get cut due to a cut map or where the density decreases, the number of values returned is smaller.
| in_nIdx | Property index. |
| out_values | UVW values. |
| CStatus GetVertexColorValues | ( | LONG | in_nIdx, |
| CFloatArray & | out_values | ||
| ) | const |
Returns an array of vertex color values (RGBA) for the vertex color property at the specified index. The values match the render hair root locations on the primitive. The index refers to the position of the property on the primitive.
In general, the size of the returned array is GetRenderHairAccessor::GetChunkHairCount() * 4. However, in the case where render hairs are generated in an area where they get cut due to a cut map or where the density decreases, the number of values returned is smaller.
| in_nIdx | Property index. |
| out_values | RGBA color values ranging from 0.0 to 1.0. |
| CStatus GetWeightMapValues | ( | LONG | in_nIdx, |
| CFloatArray & | out_values | ||
| ) | const |
Returns an array of weight map values (W) for the weight map property at the specified index. The values match the render hair root locations on the primitive. The index refers to the position of the property on the primitive.
In general, the size of the returned array is GetRenderHairAccessor::GetChunkHairCount(). However, in the case where render hairs are generated in an area where they get cut due to a cut map or where the density decreases, the number of values returned is smaller.
| in_nIdx | Property index. |
| out_values | Weight map values. |