diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 789cb0d..e0c593c 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,16 +4,13 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="8f0bafd6-58a0-4b20-aa2b-ddc3ba278873" name="Changes" comment="- Render improvements, camera plane, update">
+    <list default="true" id="8f0bafd6-58a0-4b20-aa2b-ddc3ba278873" name="Changes" comment="- added contrain context menu&#10;- improved line pickability.">
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/gui.ui" beforeDir="false" afterPath="$PROJECT_DIR$/gui.ui" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/gui_ui.py" beforeDir="false" afterPath="$PROJECT_DIR$/gui_ui.py" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/src/fluency/geometry_occ/kernel.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/fluency/geometry_occ/kernel.py" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/fluency/models/data_model.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/fluency/models/data_model.py" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/fluency/rendering/mitsuba_backend.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/fluency/rendering/mitsuba_backend.py" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/fluency/rendering/occ_renderer.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/fluency/rendering/occ_renderer.py" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/fluency/ui/dialogs.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/fluency/ui/dialogs.py" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/src/fluency/ui/main_window.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/fluency/ui/main_window.py" afterDir="false" />
-      <change beforePath="$PROJECT_DIR$/src/fluency/ui/render_window.py" beforeDir="false" afterPath="$PROJECT_DIR$/src/fluency/ui/render_window.py" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -72,6 +69,7 @@
     "Python.side_fluency.executor": "Run",
     "Python.simple_mesh.executor": "Run",
     "Python.sketch.executor": "Run",
+    "Python.surface_modifier.executor": "Run",
     "Python.vtk_widget.executor": "Run",
     "Python.vulkan.executor": "Run",
     "RunOnceActivity.OpenProjectViewOnStart": "true",
@@ -80,7 +78,7 @@
     "RunOnceActivity.git.unshallow": "true",
     "RunOnceActivity.typescript.service.memoryLimit.init": "true",
     "codeWithMe.voiceChat.enabledByDefault": "false",
-    "git-widget-placeholder": "feature/occ-migration",
+    "git-widget-placeholder": "feature/surface-modifier-pyramid-patterns",
     "last_opened_file_path": "/Volumes/Data_drive/Programming/fluency",
     "node.js.detected.package.eslint": "true",
     "node.js.selected.package.eslint": "(autodetect)",
@@ -442,7 +440,31 @@
       <option name="project" value="LOCAL" />
       <updated>1783976498520</updated>
     </task>
-    <option name="localTasksCounter" value="41" />
+    <task id="LOCAL-00041" summary="Improved render previews">
+      <option name="closed" value="true" />
+      <created>1784408804224</created>
+      <option name="number" value="00041" />
+      <option name="presentableId" value="LOCAL-00041" />
+      <option name="project" value="LOCAL" />
+      <updated>1784408804224</updated>
+    </task>
+    <task id="LOCAL-00042" summary="- added contrain context menu&#10;- improved line pickability.">
+      <option name="closed" value="true" />
+      <created>1784452692776</created>
+      <option name="number" value="00042" />
+      <option name="presentableId" value="LOCAL-00042" />
+      <option name="project" value="LOCAL" />
+      <updated>1784452692776</updated>
+    </task>
+    <task id="LOCAL-00043" summary="- added contrain context menu&#10;- improved line pickability.">
+      <option name="closed" value="true" />
+      <created>1784470032428</created>
+      <option name="number" value="00043" />
+      <option name="presentableId" value="LOCAL-00043" />
+      <option name="project" value="LOCAL" />
+      <updated>1784470032428</updated>
+    </task>
+    <option name="localTasksCounter" value="44" />
     <servers />
   </component>
   <component name="TypeScriptGeneratedFilesManager">
@@ -463,8 +485,6 @@
     <ignored-roots>
       <path value="$PROJECT_DIR$/pythonProject" />
     </ignored-roots>
-    <MESSAGE value="- Sketch projection partly works again :)" />
-    <MESSAGE value="- Added new componnt controls" />
     <MESSAGE value="- changing compos for sketches works" />
     <MESSAGE value="- changing compos including sketches and bodies" />
     <MESSAGE value="- Drawing bodys depending on the selected compo&#10;- Cut working&#10;- Edit sketch working" />
@@ -488,6 +508,8 @@
     <MESSAGE value="-  added renderer" />
     <MESSAGE value="-  added renderer&#10;- Added undo" />
     <MESSAGE value="- Render improvements, camera plane, update" />
-    <option name="LAST_COMMIT_MESSAGE" value="- Render improvements, camera plane, update" />
+    <MESSAGE value="Improved render previews" />
+    <MESSAGE value="- added contrain context menu&#10;- improved line pickability." />
+    <option name="LAST_COMMIT_MESSAGE" value="- added contrain context menu&#10;- improved line pickability." />
   </component>
 </project>
\ No newline at end of file
diff --git a/gui.ui b/gui.ui
index d8f251f..f408b20 100644
--- a/gui.ui
+++ b/gui.ui
@@ -501,6 +501,16 @@
          </property>
         </widget>
        </item>
+       <item row="3" column="0">
+        <widget class="QPushButton" name="pb_surface_mod">
+         <property name="toolTip">
+          <string>Apply surface modifier (pyramid pattern for grips)</string>
+         </property>
+         <property name="text">
+          <string>SrfMod</string>
+         </property>
+        </widget>
+       </item>
       </layout>
      </widget>
     </item>
@@ -1098,32 +1108,6 @@
       </widget>
      </widget>
     </item>
-    <item row="0" column="3" rowspan="5">
-     <widget class="QGroupBox" name="gl_box">
-      <property name="sizePolicy">
-       <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
-        <horstretch>0</horstretch>
-        <verstretch>4</verstretch>
-       </sizepolicy>
-      </property>
-      <property name="font">
-       <font>
-        <pointsize>12</pointsize>
-       </font>
-      </property>
-      <property name="title">
-       <string>Model Viewer</string>
-      </property>
-      <layout class="QHBoxLayout" name="horizontalLayout_4">
-       <property name="spacing">
-        <number>-1</number>
-       </property>
-       <property name="leftMargin">
-        <number>12</number>
-       </property>
-      </layout>
-     </widget>
-    </item>
     <item row="4" column="4">
      <widget class="QGroupBox" name="groupBox_12">
       <property name="sizePolicy">
@@ -1312,6 +1296,32 @@
       </layout>
      </widget>
     </item>
+    <item row="0" column="2" rowspan="5">
+     <widget class="QGroupBox" name="gl_box">
+      <property name="sizePolicy">
+       <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+        <horstretch>0</horstretch>
+        <verstretch>4</verstretch>
+       </sizepolicy>
+      </property>
+      <property name="font">
+       <font>
+        <pointsize>12</pointsize>
+       </font>
+      </property>
+      <property name="title">
+       <string>Model Viewer</string>
+      </property>
+      <layout class="QHBoxLayout" name="horizontalLayout_4">
+       <property name="spacing">
+        <number>-1</number>
+       </property>
+       <property name="leftMargin">
+        <number>12</number>
+       </property>
+      </layout>
+     </widget>
+    </item>
    </layout>
   </widget>
   <widget class="QMenuBar" name="menubar">
diff --git a/gui_ui.py b/gui_ui.py
index aec3c76..88fc783 100644
--- a/gui_ui.py
+++ b/gui_ui.py
@@ -289,6 +289,11 @@ class Ui_fluencyCAD(object):
 
         self.gridLayout_3.addWidget(self.pb_moveop, 1, 1, 1, 1)
 
+        self.pb_surface_mod = QPushButton(self.groupBox)
+        self.pb_surface_mod.setObjectName(u"pb_surface_mod")
+
+        self.gridLayout_3.addWidget(self.pb_surface_mod, 3, 0, 1, 1)
+
 
         self.gridLayout.addWidget(self.groupBox, 0, 4, 1, 1)
 
@@ -601,25 +606,6 @@ class Ui_fluencyCAD(object):
 
         self.gridLayout.addWidget(self.InputTab, 0, 1, 5, 1)
 
-        self.gl_box = QGroupBox(self.centralwidget)
-        self.gl_box.setObjectName(u"gl_box")
-        sizePolicy5 = QSizePolicy(QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Expanding)
-        sizePolicy5.setHorizontalStretch(0)
-        sizePolicy5.setVerticalStretch(4)
-        sizePolicy5.setHeightForWidth(self.gl_box.sizePolicy().hasHeightForWidth())
-        self.gl_box.setSizePolicy(sizePolicy5)
-        font = QFont()
-        font.setPointSize(12)
-        self.gl_box.setFont(font)
-        self.horizontalLayout_4 = QHBoxLayout(self.gl_box)
-#ifndef Q_OS_MAC
-        self.horizontalLayout_4.setSpacing(-1)
-#endif
-        self.horizontalLayout_4.setObjectName(u"horizontalLayout_4")
-        self.horizontalLayout_4.setContentsMargins(12, -1, -1, -1)
-
-        self.gridLayout.addWidget(self.gl_box, 0, 3, 5, 1)
-
         self.groupBox_12 = QGroupBox(self.centralwidget)
         self.groupBox_12.setObjectName(u"groupBox_12")
         sizePolicy2.setHeightForWidth(self.groupBox_12.sizePolicy().hasHeightForWidth())
@@ -706,6 +692,25 @@ class Ui_fluencyCAD(object):
 
         self.gridLayout.addWidget(self.groupBox_10, 3, 4, 1, 1)
 
+        self.gl_box = QGroupBox(self.centralwidget)
+        self.gl_box.setObjectName(u"gl_box")
+        sizePolicy5 = QSizePolicy(QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Expanding)
+        sizePolicy5.setHorizontalStretch(0)
+        sizePolicy5.setVerticalStretch(4)
+        sizePolicy5.setHeightForWidth(self.gl_box.sizePolicy().hasHeightForWidth())
+        self.gl_box.setSizePolicy(sizePolicy5)
+        font = QFont()
+        font.setPointSize(12)
+        self.gl_box.setFont(font)
+        self.horizontalLayout_4 = QHBoxLayout(self.gl_box)
+#ifndef Q_OS_MAC
+        self.horizontalLayout_4.setSpacing(-1)
+#endif
+        self.horizontalLayout_4.setObjectName(u"horizontalLayout_4")
+        self.horizontalLayout_4.setContentsMargins(12, -1, -1, -1)
+
+        self.gridLayout.addWidget(self.gl_box, 0, 2, 5, 1)
+
         fluencyCAD.setCentralWidget(self.centralwidget)
         self.menubar = QMenuBar(fluencyCAD)
         self.menubar.setObjectName(u"menubar")
@@ -863,6 +868,10 @@ class Ui_fluencyCAD(object):
         self.pb_cutop.setText(QCoreApplication.translate("fluencyCAD", u"Cut", None))
         self.pb_combop.setText(QCoreApplication.translate("fluencyCAD", u"Comb", None))
         self.pb_moveop.setText(QCoreApplication.translate("fluencyCAD", u"Mve", None))
+#if QT_CONFIG(tooltip)
+        self.pb_surface_mod.setToolTip(QCoreApplication.translate("fluencyCAD", u"Apply surface modifier (pyramid pattern for grips)", None))
+#endif // QT_CONFIG(tooltip)
+        self.pb_surface_mod.setText(QCoreApplication.translate("fluencyCAD", u"SrfMod", None))
         self.compo_box.setTitle(QCoreApplication.translate("fluencyCAD", u"Components", None))
         self.compo_tool_box.setTitle(QCoreApplication.translate("fluencyCAD", u"Component Tools", None))
         self.pb_new_compo.setText(QCoreApplication.translate("fluencyCAD", u"New", None))
@@ -902,7 +911,6 @@ class Ui_fluencyCAD(object):
         self.pb_apply_code.setText(QCoreApplication.translate("fluencyCAD", u"Apply Code", None))
         self.pushButton.setText(QCoreApplication.translate("fluencyCAD", u"Delete Code", None))
         self.InputTab.setTabText(self.InputTab.indexOf(self.code_tab), QCoreApplication.translate("fluencyCAD", u"Code", None))
-        self.gl_box.setTitle(QCoreApplication.translate("fluencyCAD", u"Model Viewer", None))
         self.groupBox_12.setTitle(QCoreApplication.translate("fluencyCAD", u"Component Connections", None))
         self.groupBox_13.setTitle(QCoreApplication.translate("fluencyCAD", u"Tools", None))
         self.pb_del_connection.setText(QCoreApplication.translate("fluencyCAD", u"Del", None))
@@ -913,6 +921,7 @@ class Ui_fluencyCAD(object):
         self.pb_del_body.setText(QCoreApplication.translate("fluencyCAD", u"Del", None))
         self.pb_update_body.setText(QCoreApplication.translate("fluencyCAD", u"Upd", None))
         self.pb_edt_sktch_3.setText(QCoreApplication.translate("fluencyCAD", u"Nothing", None))
+        self.gl_box.setTitle(QCoreApplication.translate("fluencyCAD", u"Model Viewer", None))
         self.menuFile.setTitle(QCoreApplication.translate("fluencyCAD", u"File", None))
         self.menuSettings.setTitle(QCoreApplication.translate("fluencyCAD", u"Settings", None))
     # retranslateUi
diff --git a/src/fluency/geometry_occ/kernel.py b/src/fluency/geometry_occ/kernel.py
index 74e42fa..e2fd4cc 100644
--- a/src/fluency/geometry_occ/kernel.py
+++ b/src/fluency/geometry_occ/kernel.py
@@ -780,3 +780,67 @@ class OCGeometryKernel(GeometryKernel):
 
         cg = props.CentreOfMass()
         return Point3D(cg.X(), cg.Y(), cg.Z())
+
+    def apply_surface_modifier(
+        self,
+        body_geometry: GeometryObject,
+        modifier_type: str = 'pyramid',
+        height: float = 2.0,
+        radius: float = 3.0,
+        spacing: float = 8.0,
+        num_rings: int = 3,
+    ) -> Optional[GeometryObject]:
+        """Apply a surface modifier to a body geometry.
+
+        Args:
+            body_geometry: The OCCGeometryObject to modify
+            modifier_type: Type of modifier ('pyramid', 'bump')
+            height: Height/depth of the pattern features
+            radius: Base radius of pattern features
+            spacing: Distance between pattern features
+            num_rings: Number of concentric rings
+
+        Returns:
+            Modified geometry, or None on failure
+        """
+        from fluency.geometry_occ.surface_modifier import SurfaceModifier
+
+        shape = self._get_shape(body_geometry)
+        if shape is None:
+            logger.error("No geometry found in body")
+            return None
+
+        modifier = SurfaceModifier()
+
+        try:
+            if modifier_type == 'pyramid':
+                result_shape = modifier.apply_pyramid_pattern(
+                    shape,
+                    pyramid_height=height,
+                    base_radius=radius,
+                    spacing=spacing,
+                    num_rings=num_rings,
+                    direction=(0, 0, 1),
+                )
+            elif modifier_type == 'bump':
+                result_shape = modifier.apply_bump_pattern(
+                    shape,
+                    bump_height=height,
+                    bump_radius=radius,
+                    spacing=spacing,
+                    num_rings=num_rings,
+                )
+            else:
+                logger.error(f"Unknown modifier type: {modifier_type}")
+                return None
+
+            if result_shape is None:
+                logger.error("Surface modifier application failed")
+                return None
+
+            # Return the modified shape wrapped in OCCGeometryObject
+            return OCCGeometryObject(result_shape)
+
+        except Exception as e:
+            logger.error(f"Error applying surface modifier: {e}", exc_info=True)
+            return None
diff --git a/src/fluency/ui/dialogs.py b/src/fluency/ui/dialogs.py
index e76f4b9..73810a8 100644
--- a/src/fluency/ui/dialogs.py
+++ b/src/fluency/ui/dialogs.py
@@ -4,16 +4,12 @@ from __future__ import annotations
 
 import logging
 import math
-from typing import Any, Dict, List, Optional, Tuple
+from typing import Tuple
 
-from PySide6.QtCore import Qt, QPoint, QPointF
-from PySide6.QtGui import QColor, QFont, QKeySequence
 from PySide6.QtWidgets import (
     QButtonGroup,
     QCheckBox,
-    QComboBox,
     QDialog,
-    QDialogButtonBox,
     QDoubleSpinBox,
     QFormLayout,
     QFrame,
@@ -24,7 +20,6 @@ from PySide6.QtWidgets import (
     QPushButton,
     QRadioButton,
     QVBoxLayout,
-    QWidget,
 )
 
 logger = logging.getLogger(__name__)
@@ -265,6 +260,95 @@ class OffsetDialog(QDialog):
         return (self.distance_input.value(), self.inward_checkbox.isChecked())
 
 
+class SurfaceModifierDialog(QDialog):
+    """Dialog for surface modifier settings."""
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        self.setWindowTitle("Surface Modifier")
+        self.setMinimumWidth(400)
+
+        layout = QVBoxLayout(self)
+
+        # Pattern type selection
+        pattern_layout = QGridLayout()
+        
+        self._pattern_group = QButtonGroup(self)
+        patterns = [
+            ("Pyramid Pattern", "pyramid"),
+            ("Bump Pattern", "bump"),
+        ]
+        for idx, (label, pattern_type) in enumerate(patterns):
+            btn = QRadioButton(label)
+            btn.setChecked(idx == 0)
+            self._pattern_group.addButton(btn, idx)
+            btn.pattern_type = pattern_type
+            pattern_layout.addWidget(btn, 0, idx)
+        layout.addLayout(pattern_layout)
+
+        # Parameters for pyramid/bump patterns
+        param_layout = QFormLayout()
+        
+        self.height_input = QDoubleSpinBox()
+        self.height_input.setDecimals(2)
+        self.height_input.setRange(0.1, 50.0)
+        self.height_input.setValue(2.0)
+        self.height_input.setSuffix(" mm")
+        param_layout.addRow("Height:", self.height_input)
+        
+        self.radius_input = QDoubleSpinBox()
+        self.radius_input.setDecimals(2)
+        self.radius_input.setRange(0.5, 20.0)
+        self.radius_input.setValue(3.0)
+        self.radius_input.setSuffix(" mm")
+        param_layout.addRow("Base Radius:", self.radius_input)
+        
+        self.spacing_input = QDoubleSpinBox()
+        self.spacing_input.setDecimals(1)
+        self.spacing_input.setRange(1.0, 50.0)
+        self.spacing_input.setValue(8.0)
+        self.spacing_input.setSuffix(" mm")
+        param_layout.addRow("Spacing:", self.spacing_input)
+        
+        layout.addLayout(param_layout)
+
+        # Number of rings
+        self.rings_input = QSpinBox()
+        self.rings_input.setMinimum(1)
+        self.rings_input.setMaximum(20)
+        self.rings_input.setValue(3)
+        param_layout.addRow("Number of Rings:", self.rings_input)
+
+        line = QFrame()
+        line.setFrameShape(QFrame.HLine)
+        layout.addWidget(line)
+
+        button_layout = QHBoxLayout()
+        ok_button = QPushButton("Apply")
+        ok_button.clicked.connect(self.accept)
+        cancel_button = QPushButton("Cancel")
+        cancel_button.clicked.connect(self.reject)
+        button_layout.addWidget(ok_button)
+        button_layout.addWidget(cancel_button)
+        layout.addLayout(button_layout)
+
+    def get_values(self) -> dict:
+        """Return the modifier settings."""
+        pattern_type = None
+        for btn in self._pattern_group.buttons():
+            if btn.isChecked():
+                pattern_type = getattr(btn, 'pattern_type', None)
+                break
+        
+        return {
+            'type': pattern_type or 'pyramid',
+            'height': self.height_input.value(),
+            'radius': self.radius_input.value(),
+            'spacing': self.spacing_input.value(),
+            'num_rings': self.rings_input.value(),
+        }
+
+
 class WorkplaneOrientationDialog(QDialog):
     """Modal dialog to choose the orientation of a new workplane.
 
@@ -404,7 +488,6 @@ class WorkplaneOrientationDialog(QDialog):
     def _on_ok(self):
         """Compute the final orientation and accept."""
         import numpy as np
-        import math
 
         if self._custom_radio.isChecked():
             # Custom: start from XY normal and rotate by the two angles.
@@ -454,7 +537,6 @@ class WorkplaneOrientationDialog(QDialog):
         whether called before or after ``_on_ok``.
         """
         import numpy as np
-        import math
 
         if self._custom_radio.isChecked():
             ax = math.radians(self._angle_x.value())
diff --git a/src/fluency/ui/main_window.py b/src/fluency/ui/main_window.py
index 52cc57c..26d18ba 100644
--- a/src/fluency/ui/main_window.py
+++ b/src/fluency/ui/main_window.py
@@ -717,6 +717,8 @@ class MainWindow(QMainWindow):
         self._btn_move = ui.pb_moveop
         self._btn_revolve = ui.pb_revop
         self._btn_array = ui.pb_arrayop
+        # ── Surface Modifier ──
+        self._btn_surface_mod = ui.pb_surface_mod
         # ── Export ──
         self._btn_export_stl = ui.pushButton_2
         self._btn_export_step = ui.pb_export_step
@@ -772,14 +774,14 @@ class MainWindow(QMainWindow):
         if panel == "viewer":
             # Viewer 2/3, sketch 1/3 — more room for 3D work, sketch stays visible.
             self._grid.setColumnStretch(1, 1)
-            self._grid.setColumnStretch(2, 2)
+            self._grid.setColumnStretch(3, 2)
         elif panel == "sketch":
             # Sketch 2/3, viewer 1/3 — comfortable sketching, 3D stays visible.
             self._grid.setColumnStretch(1, 2)
-            self._grid.setColumnStretch(2, 1)
+            self._grid.setColumnStretch(3, 1)
         else:  # equal
             self._grid.setColumnStretch(1, 1)
-            self._grid.setColumnStretch(2, 1)
+            self._grid.setColumnStretch(3, 1)
         logger.info(f"Panel focus -> {self._panel_focus}")
 
     def keyPressEvent(self, event):
@@ -832,6 +834,7 @@ class MainWindow(QMainWindow):
         self._btn_cut.clicked.connect(self._boolean_cut)
         self._btn_combine.clicked.connect(self._boolean_union)
         self._btn_revolve.clicked.connect(self._revolve_sketch)
+        self._btn_surface_mod.clicked.connect(self._open_surface_modifier_dialog)
 
         self._btn_add_sketch.clicked.connect(self._add_sketch_to_component)
         self._btn_edit_sketch.clicked.connect(self._edit_sketch)
@@ -3994,6 +3997,56 @@ class MainWindow(QMainWindow):
             logger.exception(f"Boolean union failed: {e}")
             QMessageBox.critical(self, "Error", f"Boolean union failed: {e}")
 
+    def _open_surface_modifier_dialog(self):
+        """Open the surface modifier dialog and apply to selected body."""
+        if not self._current_component or not self._selected_body:
+            QMessageBox.warning(self, "No Selection", "Please select a body first")
+            return
+
+        # Create and show the dialog
+        dialog = SurfaceModifierDialog(self)
+        accepted = dialog.exec()
+
+        if not accepted:
+            logger.info("Surface modifier dialog cancelled")
+            return
+
+        # Get the settings from the dialog
+        settings = dialog.get_values()
+        logger.info(f"Surface modifier settings: {settings}")
+
+        try:
+            # Apply the surface modifier to the selected body
+            result_geom = self._kernel.apply_surface_modifier(
+                self._selected_body.geometry,
+                **settings
+            )
+
+            if result_geom is not None:
+                # Update the body geometry
+                self._selected_body.geometry = result_geom
+                self._mark_dirty()
+
+                logger.debug("Adding shape to OCC viewer")
+                shape = self._kernel._get_shape(result_geom)
+                self._selected_body.render_object = self._viewer_3d.show_shape(
+                    shape, self._selected_body.color, self._selected_body.name
+                )
+                logger.info(f"Render object: {self._selected_body.render_object}")
+
+                self._refresh_lists()
+                self._update_component_thumbnail(self._get_active_component_index())
+                self._viewer_3d.fit_camera()
+                logger.info("Surface modifier applied successfully")
+            else:
+                QMessageBox.warning(
+                    self, "Error", "Failed to apply surface modifier"
+                )
+
+        except Exception as e:
+            logger.exception(f"Surface modifier failed: {e}")
+            QMessageBox.critical(self, "Error", f"Surface modifier failed: {e}")
+
     def _delete_body(self):
         selected = self._body_list.currentItem()
         if not selected or not self._current_component: