void SceneShapeUI::selectionRayToWorldSpacePoint( const MDagPath &camera, const MSelectInfo &selectInfo, float depth, MPoint &worldIntersectionPoint ) const
{
MPoint localRayOrigin;
MVector localRayDirection;
selectInfo.getLocalRay( localRayOrigin, localRayDirection );
MFnCamera fnCamera( camera.node() );
float near = fnCamera.nearClippingPlane();
float far = fnCamera.farClippingPlane();
float z = -1;
if( fnCamera.isOrtho() )
{
z = Imath::lerp( near, far, depth );
}
else
{
// perspective camera - depth isn't linear so linearise to get z
float a = far / ( far - near );
float b = far * near / ( near - far );
z = b / ( depth - a );
}
MMatrix localToCamera = selectInfo.selectPath().inclusiveMatrix() * camera.inclusiveMatrix().inverse();
MPoint cameraRayOrigin = localRayOrigin * localToCamera;
MVector cameraRayDirection = localRayDirection * localToCamera;
MPoint cameraIntersectionPoint = cameraRayOrigin + cameraRayDirection * ( -( z - near ) / cameraRayDirection.z );
worldIntersectionPoint = cameraIntersectionPoint * camera.inclusiveMatrix();
}
/* override */
bool apiSimpleShapeUI::select( MSelectInfo &selectInfo, MSelectionList &selectionList,
MPointArray &worldSpaceSelectPts ) const
//
// Description:
//
// Main selection routine
//
// Arguments:
//
// selectInfo - the selection state information
// selectionList - the list of selected items to add to
// worldSpaceSelectPts -
//
{
bool selected = false;
bool componentSelected = false;
bool hilited = false;
hilited = (selectInfo.displayStatus() == M3dView::kHilite);
if ( hilited ) {
componentSelected = selectVertices( selectInfo, selectionList, worldSpaceSelectPts );
selected = selected || componentSelected;
}
if ( !selected )
{
// NOTE: If the geometry has an intersect routine it should
// be called here with the selection ray to determine if the
// the object was selected.
selected = true;
MSelectionMask priorityMask( MSelectionMask::kSelectNurbsSurfaces );
MSelectionList item;
item.add( selectInfo.selectPath() );
MPoint xformedPt;
if ( selectInfo.singleSelection() ) {
MPoint center = surfaceShape()->boundingBox().center();
xformedPt = center;
xformedPt *= selectInfo.selectPath().inclusiveMatrix();
}
selectInfo.addSelection( item, xformedPt, selectionList,
worldSpaceSelectPts, priorityMask, false );
}
return selected;
}
bool BaseShapeUI::select( MSelectInfo &selectInfo, MSelectionList &selectionList, MPointArray &worldSpaceSelectPts ) const {
// Should never happen
//
if (!s_drawData.initialized) {
std::cerr << "Can't do selection, OpenGL context not initialized!" << std::endl;
return false;
}
//BaseShape *shape = (BaseShape *) surfaceShape();
MStatus status;
M3dView view = selectInfo.view();
const MDagPath & path = selectInfo.multiPath();
view.beginSelect();
glPushClientAttrib(GL_CLIENT_VERTEX_ARRAY_BIT);
glEnableClientState(GL_VERTEX_ARRAY);
glVertexPointer(3, GL_FLOAT, 0, Data::BackboneArrowVerts);
glDrawArrays(GL_TRIANGLES, 0, Data::BackboneArrowNumVerts);
glPopClientAttrib();
if ( view.endSelect() > 0 ) // Hit count > 0
{
MSelectionMask priorityMask( MSelectionMask::kSelectObjectsMask );
MSelectionList item;
item.add( selectInfo.selectPath() );
MPoint xformedPt;
xformedPt *= path.inclusiveMatrix();
selectInfo.addSelection( item, xformedPt, selectionList, worldSpaceSelectPts, priorityMask, false );
return true;
}
return false;
}
bool DrawableHolderUI::select( MSelectInfo &selectInfo, MSelectionList &selectionList, MPointArray &worldSpaceSelectPts ) const
{
MStatus s;
// early out if we're not selectable. we always allow components to be selected if we're highlighted,
// but we don't allow ourselves to be selected as a whole unless meshes are in the selection mask.
// it's not ideal that we act like a mesh, but it's at least consistent with the drawing mask we use.
if( selectInfo.displayStatus() != M3dView::kHilite )
{
MSelectionMask meshMask( MSelectionMask::kSelectMeshes );
if( !selectInfo.selectable( meshMask ) )
{
return false;
}
}
// early out if we have no scene to draw
DrawableHolder *drawableHolder = static_cast<DrawableHolder *>( surfaceShape() );
IECoreGL::ConstScenePtr scene = drawableHolder->scene();
if( !scene )
{
return false;
}
// we want to perform the selection using an IECoreGL::Selector, so we
// can avoid the performance penalty associated with using GL_SELECT mode.
// that means we don't really want to call view.beginSelect(), but we have to
// call it just to get the projection matrix for our own selection, because as far
// as i can tell, there is no other way of getting it reliably.
M3dView view = selectInfo.view();
view.beginSelect();
Imath::M44d projectionMatrix;
glGetDoublev( GL_PROJECTION_MATRIX, projectionMatrix.getValue() );
view.endSelect();
view.beginGL();
glMatrixMode( GL_PROJECTION );
glLoadMatrixd( projectionMatrix.getValue() );
IECoreGL::Selector::Mode selectionMode = IECoreGL::Selector::IDRender;
if( selectInfo.displayStatus() == M3dView::kHilite && !selectInfo.singleSelection() )
{
selectionMode = IECoreGL::Selector::OcclusionQuery;
}
std::vector<IECoreGL::HitRecord> hits;
{
IECoreGL::Selector selector( Imath::Box2f( Imath::V2f( 0 ), Imath::V2f( 1 ) ), selectionMode, hits );
IECoreGL::State::bindBaseState();
selector.baseState()->bind();
scene->render( selector.baseState() );
}
view.endGL();
if( !hits.size() )
{
return false;
}
// find the depth of the closest hit:
MIntArray componentIndices;
float depthMin = std::numeric_limits<float>::max();
for( int i=0, e = hits.size(); i < e; i++ )
{
if( hits[i].depthMin < depthMin )
{
depthMin = hits[i].depthMin;
}
}
// figure out the world space location of the closest hit
MDagPath camera;
view.getCamera( camera );
MFnCamera fnCamera( camera.node() );
float near = fnCamera.nearClippingPlane();
float far = fnCamera.farClippingPlane();
float z = -1;
if( fnCamera.isOrtho() )
{
z = Imath::lerp( near, far, depthMin );
}
else
{
// perspective camera - depth isn't linear so linearise to get z
float a = far / ( far - near );
float b = far * near / ( near - far );
z = b / ( depthMin - a );
}
MPoint localRayOrigin;
MVector localRayDirection;
selectInfo.getLocalRay( localRayOrigin, localRayDirection );
MMatrix localToCamera = selectInfo.selectPath().inclusiveMatrix() * camera.inclusiveMatrix().inverse();
MPoint cameraRayOrigin = localRayOrigin * localToCamera;
MVector cameraRayDirection = localRayDirection * localToCamera;
MPoint cameraIntersectionPoint = cameraRayOrigin + cameraRayDirection * ( -( z - near ) / cameraRayDirection.z );
MPoint worldIntersectionPoint = cameraIntersectionPoint * camera.inclusiveMatrix();
MSelectionList item;
item.add( selectInfo.selectPath() );
selectInfo.addSelection(
item, worldIntersectionPoint,
selectionList, worldSpaceSelectPts,
MSelectionMask::kSelectMeshes,
false
);
return true;
}
bool ProceduralHolderUI::select( MSelectInfo &selectInfo, MSelectionList &selectionList, MPointArray &worldSpaceSelectPts ) const
{
MStatus s;
// early out if we're not selectable. we always allow components to be selected if we're highlighted,
// but we don't allow ourselves to be selected as a whole unless meshes are in the selection mask.
// it's not ideal that we act like a mesh, but it's at least consistent with the drawing mask we use.
if( selectInfo.displayStatus() != M3dView::kHilite )
{
MSelectionMask meshMask( MSelectionMask::kSelectMeshes );
if( !selectInfo.selectable( meshMask ) )
{
return false;
}
}
// early out if we have no scene to draw
ProceduralHolder *proceduralHolder = static_cast<ProceduralHolder *>( surfaceShape() );
IECoreGL::ConstScenePtr scene = proceduralHolder->scene();
if( !scene )
{
return false;
}
// we want to perform the selection using an IECoreGL::Selector, so we
// can avoid the performance penalty associated with using GL_SELECT mode.
// that means we don't really want to call view.beginSelect(), but we have to
// call it just to get the projection matrix for our own selection, because as far
// as i can tell, there is no other way of getting it reliably.
M3dView view = selectInfo.view();
view.beginSelect();
Imath::M44d projectionMatrix;
glGetDoublev( GL_PROJECTION_MATRIX, projectionMatrix.getValue() );
view.endSelect();
view.beginGL();
glMatrixMode( GL_PROJECTION );
glLoadMatrixd( projectionMatrix.getValue() );
IECoreGL::Selector::Mode selectionMode = IECoreGL::Selector::IDRender;
if( selectInfo.displayStatus() == M3dView::kHilite && !selectInfo.singleSelection() )
{
selectionMode = IECoreGL::Selector::OcclusionQuery;
}
std::vector<IECoreGL::HitRecord> hits;
{
IECoreGL::Selector selector( Imath::Box2f( Imath::V2f( 0 ), Imath::V2f( 1 ) ), selectionMode, hits );
IECoreGL::State::bindBaseState();
selector.baseState()->bind();
scene->render( selector.baseState() );
if( selectInfo.displayStatus() != M3dView::kHilite )
{
// we're not in component selection mode. we'd like to be able to select the procedural
// object using the bounding box so we draw it too.
MPlug pDrawBound( proceduralHolder->thisMObject(), ProceduralHolder::aDrawBound );
bool drawBound = true;
pDrawBound.getValue( drawBound );
if( drawBound )
{
IECoreGL::BoxPrimitive::renderWireframe( IECore::convert<Imath::Box3f>( proceduralHolder->boundingBox() ) );
}
}
}
view.endGL();
if( !hits.size() )
{
return false;
}
// iterate over the hits, converting them into components and also finding
// the closest one.
MIntArray componentIndices;
float depthMin = std::numeric_limits<float>::max();
int depthMinIndex = -1;
for( int i=0, e = hits.size(); i < e; i++ )
{
if( hits[i].depthMin < depthMin )
{
depthMin = hits[i].depthMin;
depthMinIndex = componentIndices.length();
}
ProceduralHolder::ComponentsMap::const_iterator compIt = proceduralHolder->m_componentsMap.find( hits[i].name.value() );
assert( compIt != proceduralHolder->m_componentsMap.end() );
componentIndices.append( compIt->second.first );
}
assert( depthMinIndex >= 0 );
// figure out the world space location of the closest hit
MDagPath camera;
view.getCamera( camera );
MFnCamera fnCamera( camera.node() );
float near = fnCamera.nearClippingPlane();
float far = fnCamera.farClippingPlane();
float z = -1;
if( fnCamera.isOrtho() )
{
z = Imath::lerp( near, far, depthMin );
}
else
{
// perspective camera - depth isn't linear so linearise to get z
float a = far / ( far - near );
float b = far * near / ( near - far );
z = b / ( depthMin - a );
}
MPoint localRayOrigin;
MVector localRayDirection;
selectInfo.getLocalRay( localRayOrigin, localRayDirection );
MMatrix localToCamera = selectInfo.selectPath().inclusiveMatrix() * camera.inclusiveMatrix().inverse();
MPoint cameraRayOrigin = localRayOrigin * localToCamera;
MVector cameraRayDirection = localRayDirection * localToCamera;
MPoint cameraIntersectionPoint = cameraRayOrigin + cameraRayDirection * ( -( z - near ) / cameraRayDirection.z );
MPoint worldIntersectionPoint = cameraIntersectionPoint * camera.inclusiveMatrix();
// turn the processed hits into appropriate changes to the current selection
if( selectInfo.displayStatus() == M3dView::kHilite )
{
// selecting components
MFnSingleIndexedComponent fnComponent;
MObject component = fnComponent.create( MFn::kMeshPolygonComponent, &s ); assert( s );
if( selectInfo.singleSelection() )
{
fnComponent.addElement( componentIndices[depthMinIndex] );
}
else
{
fnComponent.addElements( componentIndices );
}
MSelectionList items;
items.add( selectInfo.multiPath(), component );
selectInfo.addSelection(
items, worldIntersectionPoint,
selectionList, worldSpaceSelectPts,
MSelectionMask::kSelectMeshFaces,
true
);
}
else
{
// selecting objects
MSelectionList item;
item.add( selectInfo.selectPath() );
selectInfo.addSelection(
item, worldIntersectionPoint,
selectionList, worldSpaceSelectPts,
MSelectionMask::kSelectMeshes,
false
);
}
return true;
}
bool apiSimpleShapeUI::selectVertices( MSelectInfo &selectInfo,
MSelectionList &selectionList,
MPointArray &worldSpaceSelectPts ) const
//
// Description:
//
// Vertex selection.
//
// Arguments:
//
// selectInfo - the selection state information
// selectionList - the list of selected items to add to
// worldSpaceSelectPts -
//
{
bool selected = false;
M3dView view = selectInfo.view();
MPoint xformedPoint;
MPoint currentPoint;
MPoint selectionPoint;
double z,previousZ = 0.0;
int closestPointVertexIndex = -1;
const MDagPath & path = selectInfo.multiPath();
// Create a component that will store the selected vertices
//
MFnSingleIndexedComponent fnComponent;
MObject surfaceComponent = fnComponent.create( MFn::kMeshVertComponent );
int vertexIndex;
// if the user did a single mouse click and we find > 1 selection
// we will use the alignmentMatrix to find out which is the closest
//
MMatrix alignmentMatrix;
MPoint singlePoint;
bool singleSelection = selectInfo.singleSelection();
if( singleSelection ) {
alignmentMatrix = selectInfo.getAlignmentMatrix();
}
// Get the geometry information
//
apiSimpleShape* shape = (apiSimpleShape*) surfaceShape();
MVectorArray* geomPtr = shape->getControlPoints();
MVectorArray& geom = *geomPtr;
// Loop through all vertices of the mesh and
// see if they lie withing the selection area
//
int numVertices = geom.length();
for ( vertexIndex=0; vertexIndex<numVertices; vertexIndex++ )
{
const MVector& point = geom[ vertexIndex ];
// Sets OpenGL's render mode to select and stores
// selected items in a pick buffer
//
view.beginSelect();
glBegin( GL_POINTS );
glVertex3f( (float)point[0],
(float)point[1],
(float)point[2] );
glEnd();
if ( view.endSelect() > 0 ) // Hit count > 0
{
selected = true;
if ( singleSelection ) {
xformedPoint = currentPoint;
xformedPoint.homogenize();
xformedPoint*= alignmentMatrix;
z = xformedPoint.z;
if ( closestPointVertexIndex < 0 || z > previousZ ) {
closestPointVertexIndex = vertexIndex;
singlePoint = currentPoint;
previousZ = z;
}
} else {
// multiple selection, store all elements
//
fnComponent.addElement( vertexIndex );
}
}
}
// If single selection, insert the closest point into the array
//
if ( selected && selectInfo.singleSelection() ) {
fnComponent.addElement(closestPointVertexIndex);
// need to get world space position for this vertex
//
selectionPoint = singlePoint;
selectionPoint *= path.inclusiveMatrix();
}
// Add the selected component to the selection list
//
if ( selected ) {
MSelectionList selectionItem;
selectionItem.add( path, surfaceComponent );
MSelectionMask mask( MSelectionMask::kSelectComponentsMask );
selectInfo.addSelection(
selectionItem, selectionPoint,
selectionList, worldSpaceSelectPts,
mask, true );
}
return selected;
}
bool SceneShapeUI::select( MSelectInfo &selectInfo, MSelectionList &selectionList, MPointArray &worldSpaceSelectPts ) const
{
MStatus s;
// early out if we're not selectable. we always allow components to be selected if we're highlighted,
// but we don't allow ourselves to be selected as a whole unless meshes are in the selection mask.
// it's not ideal that we act like a mesh, but it's at least consistent with the drawing mask we use.
if( selectInfo.displayStatus() != M3dView::kHilite )
{
MSelectionMask meshMask( MSelectionMask::kSelectMeshes );
// Apparently selectInfo.selectable() still returns true when meshes are not
// displayed by the M3dView, so we are also testing the objectDisplay status.
// This was last confirmed in Maya 2014, and is presumably a Maya bug.
if( !selectInfo.selectable( meshMask ) || !selectInfo.objectDisplayStatus( M3dView::kDisplayMeshes ) )
{
return false;
}
}
// early out if we have no scene to draw
SceneShape *sceneShape = static_cast<SceneShape *>( surfaceShape() );
if( !sceneShape->getSceneInterface() )
{
return false;
}
IECoreGL::ConstScenePtr scene = sceneShape->glScene();
if( !scene )
{
return false;
}
// we want to perform the selection using an IECoreGL::Selector, so we
// can avoid the performance penalty associated with using GL_SELECT mode.
// that means we don't really want to call view.beginSelect(), but we have to
// call it just to get the projection matrix for our own selection, because as far
// as I can tell, there is no other way of getting it reliably.
M3dView view = selectInfo.view();
view.beginSelect();
Imath::M44d projectionMatrix;
glGetDoublev( GL_PROJECTION_MATRIX, projectionMatrix.getValue() );
view.endSelect();
view.beginGL();
glMatrixMode( GL_PROJECTION );
glLoadMatrixd( projectionMatrix.getValue() );
IECoreGL::Selector::Mode selectionMode = IECoreGL::Selector::IDRender;
if( selectInfo.displayStatus() == M3dView::kHilite && !selectInfo.singleSelection() )
{
selectionMode = IECoreGL::Selector::OcclusionQuery;
}
std::vector<IECoreGL::HitRecord> hits;
{
IECoreGL::Selector selector( Imath::Box2f( Imath::V2f( 0 ), Imath::V2f( 1 ) ), selectionMode, hits );
IECoreGL::State::bindBaseState();
selector.baseState()->bind();
scene->render( selector.baseState() );
if( selectInfo.displayStatus() != M3dView::kHilite )
{
// We're not in component selection mode. We'd like to be able to select the scene shape
// using the bounding box so we draw it too but only if it is visible
MPlug pDrawBound( sceneShape->thisMObject(), SceneShape::aDrawRootBound );
bool drawBound;
pDrawBound.getValue( drawBound );
if( drawBound )
{
IECoreGL::BoxPrimitive::renderWireframe( IECore::convert<Imath::Box3f>( sceneShape->boundingBox() ) );
}
}
}
view.endGL();
if( hits.empty() )
{
return false;
}
// iterate over the hits, converting them into components and also finding
// the closest one.
MIntArray componentIndices;
float depthMin = std::numeric_limits<float>::max();
int depthMinIndex = -1;
for( unsigned int i=0, e = hits.size(); i < e; i++ )
{
if( hits[i].depthMin < depthMin )
{
depthMin = hits[i].depthMin;
depthMinIndex = componentIndices.length();
}
int index = sceneShape->selectionIndex( IECoreGL::NameStateComponent::nameFromGLName( hits[i].name ) );
componentIndices.append( index );
}
assert( depthMinIndex >= 0 );
// figure out the world space location of the closest hit
MDagPath camera;
view.getCamera( camera );
MPoint worldIntersectionPoint;
selectionRayToWorldSpacePoint( camera, selectInfo, depthMin, worldIntersectionPoint );
// turn the processed hits into appropriate changes to the current selection
if( selectInfo.displayStatus() == M3dView::kHilite )
{
// selecting components
MFnSingleIndexedComponent fnComponent;
MObject component = fnComponent.create( MFn::kMeshPolygonComponent, &s ); assert( s );
if( selectInfo.singleSelection() )
{
fnComponent.addElement( componentIndices[depthMinIndex] );
}
else
{
fnComponent.addElements( componentIndices );
}
MSelectionList items;
items.add( selectInfo.multiPath(), component );
MDagPath path = selectInfo.multiPath();
selectInfo.addSelection(
items, worldIntersectionPoint,
selectionList, worldSpaceSelectPts,
MSelectionMask::kSelectMeshFaces,
true
);
}
else
{
// Check if we should be able to select that object
MPlug pObjectOnly( sceneShape->thisMObject(), SceneShape::aObjectOnly );
bool objectOnly;
pObjectOnly.getValue( objectOnly );
if( objectOnly && !sceneShape->getSceneInterface()->hasObject() )
{
return true;
}
// selecting objects
MSelectionList item;
item.add( selectInfo.selectPath() );
selectInfo.addSelection(
item, worldIntersectionPoint,
selectionList, worldSpaceSelectPts,
MSelectionMask::kSelectMeshes,
false
);
}
return true;
}
bool SceneShapeUI::snap( MSelectInfo &snapInfo ) const
{
MStatus s;
if( snapInfo.displayStatus() != M3dView::kHilite )
{
MSelectionMask meshMask( MSelectionMask::kSelectMeshes );
if( !snapInfo.selectable( meshMask ) )
{
return false;
}
}
// early out if we have no scene to draw
SceneShape *sceneShape = static_cast<SceneShape *>( surfaceShape() );
const IECore::SceneInterface *sceneInterface = sceneShape->getSceneInterface().get();
if( !sceneInterface )
{
return false;
}
IECoreGL::ConstScenePtr scene = sceneShape->glScene();
if( !scene )
{
return false;
}
// Get the viewport that the snapping operation is taking place in.
M3dView view = snapInfo.view();
// Use an IECoreGL::Selector to find the point in world space that we wish to snap to.
// We do this by first getting the origin of the selection ray and transforming it into
// NDC space using the OpenGL projection and transformation matrices. Once we have the
// point in NDC we can use it to define the viewport that the IECoreGL::Selector will use.
MPoint localRayOrigin;
MVector localRayDirection;
snapInfo.getLocalRay( localRayOrigin, localRayDirection );
Imath::V3d org( localRayOrigin[0], localRayOrigin[1], localRayOrigin[2] );
MDagPath camera;
view.getCamera( camera );
MMatrix localToCamera = snapInfo.selectPath().inclusiveMatrix() * camera.inclusiveMatrix().inverse();
view.beginSelect();
Imath::M44d projectionMatrix;
glGetDoublev( GL_PROJECTION_MATRIX, projectionMatrix.getValue() );
view.endSelect();
double v[4][4];
localToCamera.get( v );
Imath::M44d cam( v );
Imath::V3d ndcPt3d = ( (org * cam ) * projectionMatrix + Imath::V3d( 1. ) ) * Imath::V3d( .5 );
Imath::V2d ndcPt( std::max( std::min( ndcPt3d[0], 1. ), 0. ), 1. - std::max( std::min( ndcPt3d[1], 1. ), 0. ) );
view.beginGL();
glMatrixMode( GL_PROJECTION );
glLoadMatrixd( projectionMatrix.getValue() );
float radius = .001; // The radius of the selection area in NDC.
double aspect = double( view.portWidth() ) / view.portHeight();
Imath::V2f selectionWH( radius, radius * aspect );
std::vector<IECoreGL::HitRecord> hits;
{
IECoreGL::Selector selector( Imath::Box2f( ndcPt - selectionWH, ndcPt + selectionWH ), IECoreGL::Selector::IDRender, hits );
IECoreGL::State::bindBaseState();
selector.baseState()->bind();
scene->render( selector.baseState() );
}
view.endGL();
if( hits.empty() )
{
return false;
}
// Get the closest mesh hit.
float depthMin = std::numeric_limits<float>::max();
int depthMinIndex = -1;
for( unsigned int i=0, e = hits.size(); i < e; i++ )
{
if( hits[i].depthMin < depthMin )
{
depthMin = hits[i].depthMin;
depthMinIndex = i;
}
}
// Get the absolute path of the hit object.
IECore::SceneInterface::Path objPath;
std::string objPathStr;
sceneInterface->path( objPath );
IECore::SceneInterface::pathToString( objPath, objPathStr );
objPathStr += IECoreGL::NameStateComponent::nameFromGLName( hits[depthMinIndex].name );
IECore::SceneInterface::stringToPath( objPathStr, objPath );
// Validate the hit selection.
IECore::ConstSceneInterfacePtr childInterface;
try
{
childInterface = sceneInterface->scene( objPath );
}
catch(...)
{
return false;
}
if( !childInterface )
{
return false;
}
if( !childInterface->hasObject() )
{
return false;
}
// Get the mesh primitive so that we can query it's vertices.
double time = sceneShape->time();
IECore::ConstObjectPtr object = childInterface->readObject( time );
IECore::ConstMeshPrimitivePtr meshPtr = IECore::runTimeCast<const IECore::MeshPrimitive>( object.get() );
if ( !meshPtr )
{
return false;
}
// Calculate the snap point in object space.
MPoint worldIntersectionPoint;
selectionRayToWorldSpacePoint( camera, snapInfo, depthMin, worldIntersectionPoint );
Imath::V3f pt( worldIntersectionPoint[0], worldIntersectionPoint[1], worldIntersectionPoint[2] );
Imath::M44f objToWorld( worldTransform( childInterface.get(), time ) );
pt = pt * objToWorld.inverse();
// Get the list of vertices in the mesh.
IECore::V3fVectorData::ConstPtr pointData( meshPtr->variableData<IECore::V3fVectorData>( "P", IECore::PrimitiveVariable::Vertex ) );
const std::vector<Imath::V3f> &vertices( pointData->readable() );
// Find the vertex that is closest to the snap point.
Imath::V3d closestVertex;
float closestDistance = std::numeric_limits<float>::max();
for( std::vector<Imath::V3f>::const_iterator it( vertices.begin() ); it != vertices.end(); ++it )
{
Imath::V3d vert( *it );
float d( ( pt - vert ).length() ); // Calculate the distance between the vertex and the snap point.
if( d < closestDistance )
{
closestDistance = d;
closestVertex = vert;
}
}
// Snap to the vertex.
closestVertex *= objToWorld;
snapInfo.setSnapPoint( MPoint( closestVertex[0], closestVertex[1], closestVertex[2] ) );
return true;
}