Refactoring the way to set the colormap for the vector decorators.

- option to select either uniform color, magnitude color, X, Y or Z
  component color.
- computation of the range with respect to the previous choice

src/dtkVisualization/dtkVisualizationDecoratorVectorGlyphs.cpp

@@ -21,6 +21,7 @@
 #include <vtkDataArray.h>
 #include <vtkGlyph3D.h>
 #include <vtkLookupTable.h>
+#include <vtkMaskPoints.h>
 #include <vtkPointData.h>
 #include <vtkPolyDataMapper.h>
 #include <vtkRenderer.h>
@@ -39,10 +40,12 @@ public:
 public:
     vtkSmartPointer<vtkArrowSource> source_arrow;
     vtkSmartPointer<vtkCellCenters> cell_centers;
+    vtkSmartPointer<vtkMaskPoints> mask_points;
     vtkSmartPointer<vtkGlyph3D> glyphs;
 
 public:
     QCheckBox *show_actor_cb = nullptr;
+    QSpinBox *glyphs_stride_sb = nullptr;
     QDoubleSpinBox *glyphs_scale_factor_sb = nullptr;
 };
 
@@ -56,7 +59,12 @@ dtkVisualizationDecoratorVectorGlyphs::dtkVisualizationDecoratorVectorGlyphs(voi
 
     d->cell_centers = vtkSmartPointer<vtkCellCenters>::New();
 
+    d->mask_points = vtkSmartPointer<vtkMaskPoints>::New();
+    d->mask_points->RandomModeOff();
+    d->mask_points->SetOnRatio(2); // 1 => all points are taken then no masking
+
     d->glyphs = vtkSmartPointer<vtkGlyph3D>::New();
+    d->glyphs->SetInputConnection(d->mask_points->GetOutputPort());
     d->glyphs->SetSourceConnection(d->source_arrow->GetOutputPort());
     d->glyphs->SetVectorModeToUseVector();
     d->glyphs->SetScaleModeToScaleByVector();
@@ -74,11 +82,16 @@ dtkVisualizationDecoratorVectorGlyphs::dtkVisualizationDecoratorVectorGlyphs(voi
     // Inspectors creation
 
     d->show_actor_cb = new QCheckBox;
+    d->glyphs_stride_sb = new QSpinBox;
     d->glyphs_scale_factor_sb = new QDoubleSpinBox;
 
     //////////
     // Inspectors setup
 
+    d->glyphs_stride_sb->setValue(2);
+    d->glyphs_stride_sb->setMaximum(9999999);
+    d->glyphs_stride_sb->setKeyboardTracking(false);
+
     d->glyphs_scale_factor_sb->setValue(0.1);
     d->glyphs_scale_factor_sb->setDecimals(5);
     d->glyphs_scale_factor_sb->setMaximum(1000);
@@ -93,6 +106,13 @@ dtkVisualizationDecoratorVectorGlyphs::dtkVisualizationDecoratorVectorGlyphs(voi
             this->draw();
         });
 
+    connect(d->glyphs_stride_sb, QOverload<int>::of(&QSpinBox::valueChanged), [=] (int value) {
+            this->blockSignals(true);
+            d->mask_points->SetOnRatio(value);
+            this->blockSignals(false);
+            this->draw();
+        });
+
     connect(d->glyphs_scale_factor_sb, QOverload<double>::of(&QDoubleSpinBox::valueChanged), [=] (double value) {
             this->blockSignals(true);
             d->glyphs->SetScaleFactor(value);
@@ -102,9 +122,11 @@ dtkVisualizationDecoratorVectorGlyphs::dtkVisualizationDecoratorVectorGlyphs(voi
 
     this->setObjectName("Vector Glyphs");
     d->show_actor_cb->setObjectName("Display");
+    d->glyphs_stride_sb->setObjectName("Every Nth point");
     d->glyphs_scale_factor_sb->setObjectName("Scale Factor");
 
-    d_func()->inspectors << d->show_actor_cb << d->glyphs_scale_factor_sb;
+    d_func()->inspectors << d->show_actor_cb << d_func()->field_components
+                        << d->glyphs_stride_sb << d->glyphs_scale_factor_sb;
 }
 
 dtkVisualizationDecoratorVectorGlyphs::~dtkVisualizationDecoratorVectorGlyphs(void)
@@ -227,12 +249,15 @@ bool dtkVisualizationDecoratorVectorGlyphs::setCurrentFieldName(const QString& f
     using Support = dtkVisualizationDecoratorWithClut::Support;
     int support = d_func()->supports[field_name];
     if(support == Support::Point) {
-        d->glyphs->SetInputData(d_func()->dataset);
+        d->mask_points->SetInputData(d_func()->dataset);
+        d->mask_points->SetInputArrayToProcess(0, 0, 0, vtkDataObject::FIELD_ASSOCIATION_POINTS, qPrintable(field_name));
         d->glyphs->SetInputArrayToProcess(0, 0, 0, vtkDataObject::FIELD_ASSOCIATION_POINTS, qPrintable(field_name));
     } else if(support == Support::Cell) {
-        d->glyphs->SetInputConnection(d->cell_centers->GetOutputPort());
+        d->mask_points->SetInputConnection(d->cell_centers->GetOutputPort());
+        d->mask_points->SetInputArrayToProcess(0, 0, 0, vtkDataObject::FIELD_ASSOCIATION_CELLS, qPrintable(field_name));
         d->glyphs->SetInputArrayToProcess(0, 0, 0, vtkDataObject::FIELD_ASSOCIATION_CELLS, qPrintable(field_name));
     }
+    d->mask_points->Modified();
     d->glyphs->Modified();
 
     return dtkVisualizationDecoratorWithClut::setCurrentFieldName(field_name);
@@ -242,17 +267,15 @@ void dtkVisualizationDecoratorVectorGlyphs::setColorMap(const QMap<double, QColo
 {
     dtkVisualizationDecoratorWithClut::setColorMap(new_colormap);
 
-    d_func()->color_function->SetVectorModeToMagnitude(); // Replace d->glyphs->SetColorModeToUseVector()
     d->mapper->SetLookupTable(d_func()->color_function);
 
     // The output polydata from the glyph filter hardcodes the name of the array containing vector magnitude
     // To avoid the same hardcode, one uses GetPointData()->GetScalars()->GetName() instead.
-    if (d->glyphs->GetOutput()->GetPointData()->GetScalars()) {
-        d->mapper->SelectColorArray(d->glyphs->GetOutput()->GetPointData()->GetScalars()->GetName());
+    if (d->glyphs->GetOutput()->GetPointData()->GetVectors()) {
+        d->mapper->SelectColorArray(d->glyphs->GetOutput()->GetPointData()->GetVectors()->GetName());
     } else {
         d->mapper->SelectColorArray(qPrintable(d_func()->current_field_name));
     }
-
     auto&& range = d_func()->ranges[d_func()->current_field_name];
     d->mapper->SetScalarRange(range[0], range[1]);
     d->mapper->Modified();

src/dtkVisualization/dtkVisualizationDecoratorVectorStreamTracer.cpp

@@ -337,9 +337,11 @@ dtkVisualizationDecoratorVectorStreamTracer::dtkVisualizationDecoratorVectorStre
     d->sp_radius->setObjectName("Tube Radius");
     d->sp_resolution->setObjectName("Resolution");
 
-    d_func()->inspectors << d->cb_source_type << d->cb_integrator_direction << d->cb_integrator_type << d->sp_integrator_max_steps
-                         << d->sp_integrator_max_lengths << d->sp_radius << d->sp_resolution
-                         << d->show_actor_cb << d->show_source_actor_cb;
+    d_func()->inspectors << d->show_actor_cb << d->show_source_actor_cb
+                         << d_func()->field_components
+                         << d->cb_source_type << d->cb_integrator_direction << d->cb_integrator_type << d->sp_integrator_max_steps
+                         << d->sp_integrator_max_lengths << d->sp_radius << d->sp_resolution;
+
 }
 
 dtkVisualizationDecoratorVectorStreamTracer::~dtkVisualizationDecoratorVectorStreamTracer(void)
@@ -529,7 +531,6 @@ void dtkVisualizationDecoratorVectorStreamTracer::setColorMap(const QMap<double,
 {
     dtkVisualizationDecoratorWithClut::setColorMap(new_colormap);
 
-    d_func()->color_function->SetVectorModeToMagnitude();
     d->mapper->SetLookupTable(d_func()->color_function);
     d->mapper->SelectColorArray(qPrintable(d_func()->current_field_name));
     auto&& range = d_func()->ranges[d_func()->current_field_name];

src/dtkVisualization/dtkVisualizationDecoratorWithClut.cpp

@@ -51,12 +51,21 @@ dtkVisualizationDecoratorWithClutPrivate::dtkVisualizationDecoratorWithClutPriva
     //////////
     // Inspectors creation
 
-    this->fields_box  = new QComboBox;
+    this->fields_box = new QComboBox;
+
+    this->field_components = new QComboBox;
+    this->field_components->addItem("None");
+    this->field_components->addItem("Magnitude");
+    this->field_components->addItem("X");
+    this->field_components->addItem("Y");
+    this->field_components->addItem("Z");
+    this->field_components->setCurrentIndex(0);
+
     this->fixed_range = new QCheckBox;
-    this->min_range   = new QLineEdit;
-    this->max_range   = new QLineEdit;
+    this->min_range = new QLineEdit;
+    this->max_range = new QLineEdit;
 
-    this->colormap_editor    = new dtkVisualizationWidgetsColorMapEditor;
+    this->colormap_editor = new dtkVisualizationWidgetsColorMapEditor;
 
     this->show_scalar_bar = new QCheckBox;
 
@@ -82,12 +91,12 @@ dtkVisualizationDecoratorWithClutPrivate::dtkVisualizationDecoratorWithClutPriva
     this->show_scalar_bar->setChecked(false);
 
     this->fields_box->setObjectName("Field");
+    this->field_components->setObjectName("Coloring");
     range_widget->setObjectName("");
     this->colormap_editor->setObjectName("Color Map");
     this->show_scalar_bar->setObjectName("Scalar Bar");
 
     this->inspectors << this->fields_box << this->colormap_editor << range_widget << this->show_scalar_bar;
-
 }
 
 void dtkVisualizationDecoratorWithClutPrivate::clear(void)
@@ -152,9 +161,25 @@ void dtkVisualizationDecoratorWithClutPrivate::retrieveVectorData(vtkDataSetAttr
             this->kinds[field_name] = Kind::Vector;
 
             auto&& range = this->ranges[field_name];
-            field_data->GetArray(i)->GetRange(range.data(), -1);
+            range[0] = range[1] = 0;
             this->color_transfer_functions[field_name] = this->default_color_map;
 
+            // auto&& range_magn = this->ranges[field_name + QString("__Magnitude")];
+            // field_data->GetArray(i)->GetRange(range_magn.data(), -1);
+            // this->color_transfer_functions[field_name + QString("__Magnitude")] = this->default_color_map;
+
+            // auto&& range_x = this->ranges[field_name + QString("__X")];
+            // field_data->GetArray(i)->GetRange(range_x.data(), 0);
+            // this->color_transfer_functions[field_name + QString("__X")] = this->default_color_map;
+
+            // auto&& range_y = this->ranges[field_name + QString("__Y")];
+            // field_data->GetArray(i)->GetRange(range_y.data(), 1);
+            // this->color_transfer_functions[field_name + QString("__Y")] = this->default_color_map;
+
+            // auto&& range_z = this->ranges[field_name + QString("__Z")];
+            // field_data->GetArray(i)->GetRange(range_z.data(), 2);
+            // this->color_transfer_functions[field_name + QString("__Z")] = this->default_color_map;
+
             auto opacity_function = vtkSmartPointer<vtkPiecewiseFunction>::New();
             opacity_function->RemoveAllPoints();
             opacity_function->AddPoint(0,   0.);
@@ -220,6 +245,106 @@ void dtkVisualizationDecoratorWithClutPrivate::sortEligibleFields(void)
     }
 }
 
+void dtkVisualizationDecoratorWithClutPrivate::updateRange(void)
+{
+    auto&& range = this->ranges[this->current_field_name];
+
+    if (!this->fixed_range->isChecked()) {
+        // The following trick gives directly the right index value
+        // to extract in the GetRange method for the vector case.
+        int component_id = this->field_components->currentIndex() - 2;
+
+        using Kind = dtkVisualizationDecoratorWithClutPrivate::Kind;
+        using Support = dtkVisualizationDecoratorWithClutPrivate::Support;
+
+        switch (this->kinds[this->current_field_name]) {
+        case Kind::Scalar:
+            switch (this->supports[this->current_field_name]) {
+            case Support::Point:
+                this->dataset->GetPointData()->GetArray(qPrintable(this->current_field_name))->Modified();
+                this->dataset->GetPointData()->GetArray(qPrintable(this->current_field_name))->GetRange(range.data(), -1);
+                break;
+            case Support::Cell:
+                this->dataset->GetCellData()->GetArray(qPrintable(this->current_field_name))->Modified();
+                this->dataset->GetCellData()->GetArray(qPrintable(this->current_field_name))->GetRange(range.data(), -1);
+                break;
+            default:
+                break;
+            }
+            break;
+
+        case Kind::Vector:
+            if (component_id > -2) {
+
+                switch (this->supports[this->current_field_name]) {
+                case Support::Point:
+                    this->dataset->GetPointData()->GetArray(qPrintable(this->current_field_name))->Modified();
+                    this->dataset->GetPointData()->GetArray(qPrintable(this->current_field_name))->GetRange(range.data(), component_id);
+                    break;
+                case Support::Cell:
+                    this->dataset->GetCellData()->GetArray(qPrintable(this->current_field_name))->Modified();
+                    this->dataset->GetCellData()->GetArray(qPrintable(this->current_field_name))->GetRange(range.data(), component_id);
+                    break;
+                default:
+                    break;
+                }
+            } else {
+                range[0] = range[1] = 0;
+            }
+            break;
+        default:
+            break;
+        }
+    }
+
+    this->min_range->blockSignals(true);
+    this->min_range->setText(QString::number(range[0]));
+    this->min_range->blockSignals(false);
+
+    this->max_range->blockSignals(true);
+    this->max_range->setText(QString::number(range[1]));
+    this->max_range->blockSignals(false);
+}
+
+void dtkVisualizationDecoratorWithClutPrivate::updateColorTransferFunction(void)
+{
+    using Kind = dtkVisualizationDecoratorWithClutPrivate::Kind;
+    // The following trick gives directly the right index value
+    // to extract in the GetRange method for the vector case.
+    int component_id = this->field_components->currentIndex() - 2;
+
+    switch (this->kinds[this->current_field_name]) {
+    case Kind::Vector:
+        switch(component_id) {
+        case -1:
+            this->color_function->SetVectorModeToMagnitude();
+            break;
+        case 0:
+            this->color_function->SetVectorModeToComponent();
+            this->color_function->SetVectorComponent(0);
+            break;
+        case 1:
+            this->color_function->SetVectorModeToComponent();
+            this->color_function->SetVectorComponent(1);
+            break;
+        case 2:
+            this->color_function->SetVectorModeToComponent();
+            this->color_function->SetVectorComponent(2);
+            break;
+        default:
+            this->color_function->SetVectorModeToMagnitude();
+            break;
+        }
+        break;
+    default:
+        break;
+    }
+
+    this->colormap_editor->blockSignals(true);
+    this->colormap_editor->setValue(this->color_transfer_functions[this->current_field_name]);
+    this->colormap_editor->blockSignals(false);
+}
+
 // ///////////////////////////////////////////////////////////////////
 // dtkVisualizationDecoratorWithClut implementation
 // ///////////////////////////////////////////////////////////////////
@@ -234,6 +359,9 @@ dtkVisualizationDecoratorWithClut::dtkVisualizationDecoratorWithClut(void): dtkV
             this->saveSettings("field_name", field_name);
             this->touch();
         });
+    connect(d->field_components, QOverload<int>::of(&QComboBox::currentIndexChanged), [=] (int component_id) {
+            this->touch();
+        });
 
     connect(d->min_range, &QLineEdit::editingFinished, [=] () {
             d->fixed_range->blockSignals(true);
@@ -326,33 +454,9 @@ void dtkVisualizationDecoratorWithClut::touch(void)
     }
 
     // Update range
-    auto&& range = d->ranges[d->current_field_name];
-    if(!d->fixed_range->isChecked()) {
-        using Support = dtkVisualizationDecoratorWithClutPrivate::Support;
-        switch (d->supports[d->current_field_name]) {
-        case Support::Point:
-            d->dataset->GetPointData()->GetArray(qPrintable(d->current_field_name))->Modified();
-            d->dataset->GetPointData()->GetArray(qPrintable(d->current_field_name))->GetRange(range.data(), -1);
-            break;
-        case Support::Cell:
-            d->dataset->GetCellData()->GetArray(qPrintable(d->current_field_name))->Modified();
-            d->dataset->GetCellData()->GetArray(qPrintable(d->current_field_name))->GetRange(range.data(), -1);
-            break;
-        default:
-            return;
-        }
-    }
-    d->min_range->blockSignals(true);
-    d->min_range->setText(QString::number(range[0]));
-    d->min_range->blockSignals(false);
-
-    d->max_range->blockSignals(true);
-    d->max_range->setText(QString::number(range[1]));
-    d->max_range->blockSignals(false);
+    d->updateRange();
 
-    d->colormap_editor->blockSignals(true);
-    d->colormap_editor->setValue(d->color_transfer_functions[d->current_field_name]);
-    d->colormap_editor->blockSignals(false);
+    d->updateColorTransferFunction();
     this->setColorMap(d->colormap_editor->value());
 }
 

src/dtkVisualization/dtkVisualizationDecoratorWithClut_p.h

@@ -35,6 +35,7 @@ class vtkDataSetAttributes;
 class vtkPiecewiseFunction;
 class vtkPiecewiseFunction;
 class vtkScalarBarActor;
+class vtkTransform;
 
 class DTKVISUALIZATION_EXPORT dtkVisualizationDecoratorWithClutPrivate
 {
@@ -63,6 +64,7 @@ public:
     QList<QWidget *> inspectors;
 
     QComboBox *fields_box  = nullptr;
+    QComboBox *field_components = nullptr;
     QCheckBox *fixed_range = nullptr;
     QLineEdit *min_range   = nullptr;
     QLineEdit *max_range   = nullptr;
@@ -101,6 +103,8 @@ public:
     void retrieveVectorPoints(vtkDataSet *);
     void retrieveVectorCells(vtkDataSet *);
     void sortEligibleFields(void);
+    void updateRange(void);
+    void updateColorTransferFunction(void);
 
 private:
     void retrieveScalarData(vtkDataSetAttributes *, Support support);