Improve progression of the progress bar during cartogram creation

Author: mthh

dist_cartogram.py

@@ -606,9 +606,9 @@ def state_ok_button(self):
 
         self.dlg.button_box.button(QDialogButtonBox.Ok).setEnabled(result)
 
-    def startWorker(self, src_pts, img_pts, precision, max_extent, layers):
+    def startWorker(self, src_pts, img_pts, precision, max_extent, layers, total_features):
         worker = DistCartogramWorker(
-            src_pts, img_pts, precision, max_extent, layers, self.display, self.tr
+            src_pts, img_pts, precision, max_extent, layers, self.display, self.tr, total_features,
         )
         thread = QThread()
         worker.moveToThread(thread)
@@ -737,13 +737,7 @@ def run(self):
 
                 total_features = get_total_features(background_layers)
 
-                self.progressBar.setMaximum(
-                    int(
-                        15
-                        + total_features
-                        + (source_layer.featureCount() * precision) / 1.5
-                    )
-                )
+                self.progressBar.setMaximum(int(0.20 * total_features + total_features))
 
                 self.display = {
                     "source_grid": self.dlg.checkBoxSourceGrid.isChecked(),
@@ -772,7 +766,7 @@ def run(self):
                     deplacement_factor,
                     self.display["image_points"],
                 )
-                self.updateProgressBar(5)
+                self.updateProgressBar(int(0.05 * total_features))
                 if len(source_to_use) == 0 or len(image_to_use) == 0:
                     self.iface.messageBar().pushCritical(
                         self.tr("Error"),
@@ -800,6 +794,7 @@ def run(self):
                     precision,
                     max_extent,
                     background_layers,
+                    total_features,
                 )
 
             else:
@@ -820,13 +815,7 @@ def run(self):
 
                 total_features = get_total_features(background_layers)
 
-                self.progressBar.setMaximum(
-                    int(
-                        15
-                        + total_features
-                        + (precision * image_layer.featureCount()) / 1.5
-                    )
-                )
+                self.progressBar.setMaximum(int(0.20 * total_features + total_features))
 
                 if source_layer.featureCount() != image_layer.featureCount():
                     self.updateStatusMessage(
@@ -840,7 +829,7 @@ def run(self):
                     source_layer, image_layer, id_field_source, id_field_image
                 )
 
-                self.updateProgressBar(5)
+                self.updateProgressBar(int(0.05 * total_features))
 
                 extent = get_merged_extent(
                     background_layers + [source_layer, image_layer]
@@ -857,4 +846,5 @@ def run(self):
                     precision,
                     max_extent,
                     background_layers,
+                    total_features,
                 )

worker.py

@@ -45,7 +45,7 @@ class DistCartogramWorker(QObject):
     status = pyqtSignal(str)
 
     def __init__(
-        self, src_pts, image_pts, precision, extent, layers_to_transform, to_display, tr
+        self, src_pts, image_pts, precision, extent, layers_to_transform, to_display, tr, total_features,
     ):
         QObject.__init__(self)
 
@@ -56,6 +56,7 @@ def __init__(
         self.layers_to_transform = layers_to_transform
         self.to_display = to_display
         self.tr = tr
+        self.total_features = total_features
 
     def get_transformed_layers(self):
         transformed_layers = []
@@ -163,14 +164,18 @@ def _get_inter_nb_iter(coef_iter):
 
             self.status.emit(self.tr("Creation of interpolation grid..."))
             self.g = Grid(self.src_pts, self.precision, self.extent)
+
             self.status.emit(self.tr("Interpolation process..."))
-            self.progress.emit(((self.precision * len(self.image_pts)) / 3))
+            self.progress.emit(int(0.03 * self.total_features))
             self.g.interpolate(self.image_pts, _get_inter_nb_iter(4))
-            self.progress.emit(((self.precision * len(self.image_pts)) / 3))
+
+            self.progress.emit(int(0.07 * self.total_features))
             self.status.emit(self.tr("Transforming layers..."))
             transformed_layers = self.get_transformed_layers()
 
             self.status.emit(self.tr("Preparing results for displaying..."))
+            self.progress.emit(int(0.02 * self.total_features))
+
             if self.to_display["source_grid"]:
                 polys = self.g._get_grid_coords("source")
                 source_grid_layer = make_grid_layer(
@@ -179,7 +184,8 @@ def _get_inter_nb_iter(coef_iter):
             else:
                 source_grid_layer = None
 
-            self.progress.emit(5)
+            self.progress.emit(int(0.03 * self.total_features))
+
             if self.to_display["trans_grid"]:
                 polys = self.g._get_grid_coords("interp")
                 trans_grid_layer = make_grid_layer(