void
SOP_PrimGroupCentroid::baryCenter(const GU_Detail *input_geo,
GA_Range &pr_range,
const GA_PrimitiveList &prim_list,
UT_Vector3 &pos)
{
GA_Range pt_range;
GA_OffsetArray points;
GA_OffsetArray::const_iterator points_it;
// We need to iterate over each primitive in the range and
// find out which points it references.
for (GA_Iterator pr_it(pr_range); !pr_it.atEnd(); ++pr_it)
{
// Get the range of points for the primitive using the
// offset from the primitive list.
pt_range = prim_list.get(*pr_it)->getPointRange();
// Add each point's offset to the array, checking for duplicates.
for (GA_Iterator pt_it(pt_range); !pt_it.atEnd(); ++pt_it)
points.append(*pt_it, true);
}
// Reset the position.
pos.assign(0,0,0);
// Add the positions for all the points.
for (points_it = points.begin(); !points_it.atEnd(); ++points_it)
pos += input_geo->getPos3(*points_it);
// Store the average position for all the points we found.
pos /= points.entries();
}
void
SOP_PrimGroupCentroid::centerOfMass(GA_Range &pr_range,
const GA_PrimitiveList &prim_list,
UT_Vector3 &pos)
{
fpreal area, total_area;
const GEO_Primitive *prim;
// Set the position and total area to 0.
pos.assign(0,0,0);
total_area = 0;
// Iterate over all the primitives in the range.
for (GA_Iterator it(pr_range); !it.atEnd(); ++it)
{
// Get the primitive.
prim = (const GEO_Primitive *) prim_list.get(*it);
// Calculate the area of the primitive.
area = prim->calcArea();
// Add the barycenter multiplied by the area to the position.
pos += prim->baryCenter() * area;
// Add this primitive's area to the total area.
total_area += area;
}
// If the total area is not 0, divide the position by the total area.
if (total_area)
pos /= total_area;
}
OP_ERROR
SOP_Smoke_Source::cookMySop(OP_Context &context)
{
// We must lock our inputs before we try to access their geometry.
// OP_AutoLockInputs will automatically unlock our inputs when we return.
// NOTE: Don't call unlockInputs yourself when using this!
OP_AutoLockInputs inputs(this);
if (inputs.lock(context) >= UT_ERROR_ABORT)
return error();
fpreal now = context.getTime();
duplicateSource(0, context);
// These three lines enable the local variable support. This allows
// $CR to get the red colour, for example, as well as supporting
// any varmap created by the Attribute Create SOP.
// Note that if you override evalVariableValue for your own
// local variables (like SOP_Star does) it is essential you
// still call the SOP_Node::evalVariableValue or you'll not
// get any of the benefit of the built in local variables.
// The variable order controls precedence for which attribute will be
// be bound first if the same named variable shows up in multiple
// places. This ordering ensures point attributes get precedence.
setVariableOrder(3, 2, 0, 1);
// The setCur* functions track which part of the gdp is currently
// being processed - it is what is used in the evalVariableValue
// callback as the current point. The 0 is for the first input,
// you can have two inputs so $CR2 would get the second input's
// value.
setCurGdh(0, myGdpHandle);
// Builds the lookup table matching attributes to the local variables.
setupLocalVars();
// Here we determine which groups we have to work on. We only
// handle point groups.
if (error() < UT_ERROR_ABORT && cookInputGroups(context) < UT_ERROR_ABORT &&
(!myGroup || !myGroup->isEmpty()))
{
UT_AutoInterrupt progress("Flattening Points");
// Handle all position, normal, and vector attributes.
// It's not entirely clear what to do for quaternion or transform attributes.
// We bump the data IDs of the attributes to modify in advance,
// since we're already looping over them, and we want to avoid
// bumping them all for each point, in case that's slow.
UT_Array<GA_RWHandleV3> positionattribs(1);
UT_Array<GA_RWHandleV3> normalattribs;
UT_Array<GA_RWHandleV3> vectorattribs;
GA_Attribute *attrib;
GA_FOR_ALL_POINT_ATTRIBUTES(gdp, attrib)
{
// Skip non-transforming attributes
if (!attrib->needsTransform())
continue;
GA_TypeInfo typeinfo = attrib->getTypeInfo();
if (typeinfo == GA_TYPE_POINT || typeinfo == GA_TYPE_HPOINT)
{
GA_RWHandleV3 handle(attrib);
if (handle.isValid())
{
positionattribs.append(handle);
attrib->bumpDataId();
}
}
else if (typeinfo == GA_TYPE_NORMAL)
{
GA_RWHandleV3 handle(attrib);
if (handle.isValid())
{
normalattribs.append(handle);
attrib->bumpDataId();
}
}
else if (typeinfo == GA_TYPE_VECTOR)
{
GA_RWHandleV3 handle(attrib);
if (handle.isValid())
{
vectorattribs.append(handle);
attrib->bumpDataId();
}
}
}
// Iterate over points up to GA_PAGE_SIZE at a time using blockAdvance.
GA_Offset start;
GA_Offset end;
for (GA_Iterator it(gdp->getPointRange(myGroup)); it.blockAdvance(start, end);)
{
// Check if user requested abort
if (progress.wasInterrupted())
break;
for (GA_Offset ptoff = start; ptoff < end; ++ptoff)
{
// This sets the current point that is beint processed to
// ptoff. This means that ptoff will be used for any
// local variable for any parameter evaluation that occurs
// after this point.
// NOTE: Local variables and repeated parameter evaluation
// is significantly slower and sometimes more complicated
// than having a string parameter that specifies the name
// of an attribute whose values should be used instead.
// That parameter would only need to be evaluated once,
// the attribute could be looked up once, and quickly
// accessed; however, a separate point attribute would
// be needed for each property that varies per point.
// Local variable evaluation isn't threadsafe either,
// whereas attributes can be read safely from multiple
// threads.
//
// Long story short: *Local variables are terrible.*
myCurPtOff[0] = ptoff;
float dist = DIST(now);
UT_Vector3 normal;
if (!DIRPOP())
{
switch (ORIENT())
{
case 0 : // XY Plane
normal.assign(0, 0, 1);
break;
case 1 : // YZ Plane
normal.assign(1, 0, 0);
break;
case 2 : // XZ Plane
normal.assign(0, 1, 0);
break;
}
}
else
{
normal.assign(NX(now), NY(now), NZ(now));
normal.normalize();
}
// Project positions onto the plane by subtracting
// off the normal component.
for (exint i = 0; i < positionattribs.size(); ++i)
{
UT_Vector3 p = positionattribs(i).get(ptoff);
p -= normal * (dot(normal, p) - dist);
positionattribs(i).set(ptoff, p);
}
// Normals will now all either be normal or -normal.
for (exint i = 0; i < normalattribs.size(); ++i)
{
UT_Vector3 n = normalattribs(i).get(ptoff);
if (dot(normal, n) < 0)
n = -normal;
else
n = normal;
normalattribs(i).set(ptoff, n);
}
// Project vectors onto the plane through the origin by
// subtracting off the normal component.
for (exint i = 0; i < vectorattribs.size(); ++i)
{
UT_Vector3 v = vectorattribs(i).get(ptoff);
v -= normal * dot(normal, v);
vectorattribs(i).set(ptoff, v);
}
}
}
}