PDT: Modify Fillet functionality

This enables two non-connected edges to be filleted. The Process starts with an
intersection of the two edges, then fillets the corner according to input values
in the UI. This option is selected by setting the Int/Fillet checkbox.

The command Line version now takes the `fi...` format to intersect first. e.g.

`fi1.1,6,0.05` performs an intersected fillet of 1.6 units radius, 6 segments,
concave profile.

6 files changed, 100 insertions, 25 deletions

diff --git a/precision_drawing_tools/__init__.py b/precision_drawing_tools/__init__.py
index e99e7735..926dcc30 100644
--- a/precision_drawing_tools/__init__.py
+++ b/precision_drawing_tools/__init__.py
@@ -83,6 +83,7 @@ from .pdt_msg_strings import (
     PDT_DES_FILLETRAD,
     PDT_DES_FILLETSEG,
     PDT_DES_FILLETVERTS,
+    PDT_DES_FILLINT,
     PDT_DES_FLIPANG,
     PDT_DES_FLIPPER,
     PDT_DES_LIBCOLS,
@@ -419,6 +420,11 @@ class PDTSceneProperties(PropertyGroup):
         default=True,
         description=PDT_DES_FILLETVERTS,
     )
+    fillet_int : BoolProperty(
+        name="Intersect",
+        default=False,
+        description=PDT_DES_FILLINT,
+    )
 
 
 class PDTPreferences(AddonPreferences):
diff --git a/precision_drawing_tools/pdt_command.py b/precision_drawing_tools/pdt_command.py
index b293dc0d..4206b199 100644
--- a/precision_drawing_tools/pdt_command.py
+++ b/precision_drawing_tools/pdt_command.py
@@ -30,6 +30,7 @@ from .pdt_functions import (
     debug,
     disAng,
     getPercent,
+    intersection,
     objCheck,
     oops,
     updateSel,
@@ -86,6 +87,7 @@ def pdt_help(self, context):
     label(text="- Fillet Options:")
     label(text="v: Fillet Vertices")
     label(text="e: Fillet Edges")
+    label(text="i: Fillet & Intersect 2 Disconnected Edges")
     label(text="- Math Options:")
     label(text="x, y, z: Send result to X, Y and Z input fields in PDT Design")
     label(text="d, a, p: Send result to Distance, Angle or Percent input field in PDT Design")
@@ -226,9 +228,9 @@ def command_run(self, context):
         elif mode == "o":
             pg.mathsout = num
         return
-    # "x"/"y"/"z" modes are only legal for Math Operation
+    # "o"/"x"/"y"/"z" modes are only legal for Math Operation
     else:
-        if mode in {"x", "y", "z"}:
+        if mode in {"o", "x", "y", "z"}:
             pg.error = PDT_ERR_BADCOORDL
             context.window_manager.popup_menu(oops, title="Error", icon="ERROR")
             return
@@ -855,7 +857,7 @@ def command_run(self, context):
     # ---------------
     # Fillet Geometry
     elif oper == "F":
-        if mode not in {"v", "e"}:
+        if mode not in {"v", "e", "i"}:
             pg.error = f"'{mode}' {PDT_ERR_NON_VALID} '{oper}'"
             context.window_manager.popup_menu(oops, title="Error", icon="ERROR")
             return
@@ -871,7 +873,7 @@ def command_run(self, context):
             pg.error = PDT_ERR_BAD3VALS
             context.window_manager.popup_menu(oops, title="Error", icon="ERROR")
             return
-        if mode == "v":
+        if mode in {"i", "v"}:
             vert_bool = True
         elif mode == "e":
             vert_bool = False
@@ -889,6 +891,32 @@ def command_run(self, context):
         _profile = float(vals[2])
         if _profile < 0.0 or _profile > 1.0:
             _profile = 0.5  # This is a circular profile
+        if mode == "i":
+            # Fillet & Intersect Two Edges
+            edges = [e for e in bm.edges if e.select]
+            if len(edges) == 2 and len(verts) == 4:
+                va = edges[0].verts[0]
+                vo = edges[0].verts[1]
+                vl = edges[1].verts[0]
+                vf = edges[1].verts[1]
+                vector_delta, done = intersection(va.co, vo.co, vl.co, vf.co, plane)
+                if not done:
+                    errmsg = f"{PDT_ERR_INT_LINES} {plane}  {PDT_LAB_PLANE}"
+                    self.report({"ERROR"}, errmsg)
+                    return {"FINISHED"}
+                if (va.co - vector_delta).length < (vo.co - vector_delta).length:
+                    va.co = vector_delta
+                    vo.select_set(False)
+                else:
+                    vo.co = vector_delta
+                    va.select_set(False)
+                if (vl.co - vector_delta).length < (vf.co - vector_delta).length:
+                    vl.co = vector_delta
+                    vf.select_set(False)
+                else:
+                    vf.co = vector_delta
+                    vl.select_set(False)
+                bmesh.ops.remove_doubles(bm, verts=bm.verts, dist=0.0001)
         bpy.ops.mesh.bevel(
             offset_type="OFFSET",
             offset=_offset,
diff --git a/precision_drawing_tools/pdt_design.py b/precision_drawing_tools/pdt_design.py
index a20ebdd4..2d69877b 100644
--- a/precision_drawing_tools/pdt_design.py
+++ b/precision_drawing_tools/pdt_design.py
@@ -56,6 +56,7 @@ from .pdt_msg_strings import (
     PDT_ERR_SEL_2_OBJS,
     PDT_ERR_SEL_2_VERTIO,
     PDT_ERR_SEL_2_VERTS,
+    PDT_ERR_SEL_2_EDGES,
     PDT_ERR_SEL_3_OBJS,
     PDT_ERR_SEL_3_VERTIO,
     PDT_ERR_SEL_3_VERTS,
@@ -837,13 +838,9 @@ class PDT_OT_PlacementInt(Operator):
             elif len(edges) == 2:
                 ext_a = pg.extend
                 va = edges[0].verts[0]
-                actV = va.co
                 vo = edges[0].verts[1]
-                othV = vo.co
                 vl = edges[1].verts[0]
-                lstV = vl.co
                 vf = edges[1].verts[1]
-                fstV = vf.co
             else:
                 errmsg = (
                     PDT_ERR_SEL_4_VERTS
@@ -854,7 +851,7 @@ class PDT_OT_PlacementInt(Operator):
                 )
                 self.report({"ERROR"}, errmsg)
                 return {"FINISHED"}
-            vector_delta, done = intersection(actV, othV, lstV, fstV, plane)
+            vector_delta, done = intersection(va.co, vo.co, vl.co, vf.co, plane)
             if not done:
                 errmsg = f"{PDT_ERR_INT_LINES} {plane}  {PDT_LAB_PLANE}"
                 self.report({"ERROR"}, errmsg)
@@ -880,7 +877,7 @@ class PDT_OT_PlacementInt(Operator):
                 nVert = None
                 proc = False
 
-                if (actV - vector_delta).length < (othV - vector_delta).length:
+                if (va.co - vector_delta).length < (vo.co - vector_delta).length:
                     if oper == "MV":
                         va.co = vector_delta
                         proc = True
@@ -895,7 +892,7 @@ class PDT_OT_PlacementInt(Operator):
                         nVert = bm.verts.new(vector_delta)
                         bm.edges.new([vo, nVert])
 
-                if (lstV - vector_delta).length < (fstV - vector_delta).length:
+                if (vl.co - vector_delta).length < (vf.co - vector_delta).length:
                     if oper == "MV" and ext_a:
                         vl.co = vector_delta
                     elif oper == "EV" and ext_a:
@@ -1186,22 +1183,63 @@ class PDT_OT_Fillet(Operator):
 
         scene = context.scene
         pg = scene.pdt_pg
+        plane = pg.plane
         obj = context.view_layer.objects.active
         bm = bmesh.from_edit_mesh(obj.data)
         verts = [v for v in bm.verts if v.select]
-        if len(verts) == 0:
-            errmsg = PDT_ERR_SEL_1_VERT
-            self.report({"ERROR"}, errmsg)
-            return {"FINISHED"}
+        if pg.fillet_int:
+            # Fillet & Intersect Two Edges
+            edges = [e for e in bm.edges if e.select]
+            if len(edges) == 2 and len(verts) == 4:
+                va = edges[0].verts[0]
+                vo = edges[0].verts[1]
+                vl = edges[1].verts[0]
+                vf = edges[1].verts[1]
+                vector_delta, done = intersection(va.co, vo.co, vl.co, vf.co, plane)
+                if not done:
+                    errmsg = f"{PDT_ERR_INT_LINES} {plane}  {PDT_LAB_PLANE}"
+                    self.report({"ERROR"}, errmsg)
+                    return {"FINISHED"}
+                if (va.co - vector_delta).length < (vo.co - vector_delta).length:
+                    va.co = vector_delta
+                    vo.select_set(False)
+                else:
+                    vo.co = vector_delta
+                    va.select_set(False)
+                if (vl.co - vector_delta).length < (vf.co - vector_delta).length:
+                    vl.co = vector_delta
+                    vf.select_set(False)
+                else:
+                    vf.co = vector_delta
+                    vl.select_set(False)
+                bmesh.ops.remove_doubles(bm, verts=bm.verts, dist=0.0001)
+                bpy.ops.mesh.bevel(
+                    offset_type="OFFSET",
+                    offset=pg.fillet_radius,
+                    segments=pg.fillet_segments,
+                    profile=pg.fillet_profile,
+                    vertex_only=True,
+                )
+                return {"FINISHED"}
+            else:
+                errmsg = f"{PDT_ERR_SEL_2_EDGES} {len(edges)})"
+                self.report({"ERROR"}, errmsg)
+                return {"FINISHED"}
         else:
-            bpy.ops.mesh.bevel(
-                offset_type="OFFSET",
-                offset=pg.fillet_radius,
-                segments=pg.fillet_segments,
-                profile=pg.fillet_profile,
-                vertex_only=pg.fillet_vertices_only,
-            )
-            return {"FINISHED"}
+            if len(verts) == 0:
+                errmsg = PDT_ERR_SEL_1_VERT
+                self.report({"ERROR"}, errmsg)
+                return {"FINISHED"}
+            else:
+                # Intersct Edges
+                bpy.ops.mesh.bevel(
+                    offset_type="OFFSET",
+                    offset=pg.fillet_radius,
+                    segments=pg.fillet_segments,
+                    profile=pg.fillet_profile,
+                    vertex_only=pg.fillet_vertices_only,
+                )
+                return {"FINISHED"}
 
 
 class PDT_OT_Angle2(Operator):
diff --git a/precision_drawing_tools/pdt_functions.py b/precision_drawing_tools/pdt_functions.py
index f766cf31..01e595ff 100644
--- a/precision_drawing_tools/pdt_functions.py
+++ b/precision_drawing_tools/pdt_functions.py
@@ -500,7 +500,7 @@ def objCheck(obj, scene, oper):
             else:
                 return bm, True
         if len(bm.select_history) >= 1:
-            if _oper not in {"D", "E", "G", "N", "S"}:
+            if _oper not in {"D", "E", "F", "G", "N", "S"}:
                 actV = checkSelection(1, bm, obj)
             else:
                 verts = [v for v in bm.verts if v.select]
diff --git a/precision_drawing_tools/pdt_menus.py b/precision_drawing_tools/pdt_menus.py
index a3b03a40..139fb3a4 100644
--- a/precision_drawing_tools/pdt_menus.py
+++ b/precision_drawing_tools/pdt_menus.py
@@ -188,6 +188,7 @@ class PDT_PT_PanelDesign(Panel):
         row.prop(pdt_pg, "fillet_vertices_only", text=PDT_LAB_USEVERTS)
         row = box.row()
         row.operator("pdt.fillet", text=f"{PDT_LAB_FILLET}")
+        row.prop(pdt_pg, "fillet_int", text="Int/Fillet")
 
 
 class PDT_PT_PanelPivotPoint(Panel):
diff --git a/precision_drawing_tools/pdt_msg_strings.py b/precision_drawing_tools/pdt_msg_strings.py
index 72f55924..703a0b7b 100644
--- a/precision_drawing_tools/pdt_msg_strings.py
+++ b/precision_drawing_tools/pdt_msg_strings.py
@@ -84,6 +84,7 @@ PDT_ERR_SEL_1_VERT    = "Select at least 1 Vertex (Currently selected:"
 PDT_ERR_SEL_2_VERTI   = "Select at least 2 Vertices Individually (Currently selected:"
 PDT_ERR_SEL_2_VERTIO  = "Select Exactly 2 Vertices Individually (Currently selected:"
 PDT_ERR_SEL_2_VERTS   = "Select Exactly 2 Vertices (Currently selected:"
+PDT_ERR_SEL_2_EDGES   = "Select Only 2 Non-Intersecting Edges (Currently selected:"
 PDT_ERR_SEL_3_VERTS   = "Select Exactly 3 Vertices (Currently selected:"
 PDT_ERR_SEL_3_VERTIO  = "Select Exactly 3 Vertices Individually (Currently selected:"
 PDT_ERR_SEL_2_V_1_E   = "Select 2 Vertices Individually, or 1 Edge (Currently selected:"
@@ -113,7 +114,7 @@ PDT_ERR_SCALEZERO     = "Scale Distance is 0"
 
 PDT_ERR_CHARS_NUM     = "Bad Command Format, not enough Characters"
 PDT_ERR_BADFLETTER    = "Bad Operator (1st Letter); C D E F G N M P S V or ? only"
-PDT_ERR_BADSLETTER    = "Bad Mode (2nd Letter); A D I or P only (+ X Y & Z for Maths) (+ V & G for Fillet)"
+PDT_ERR_BADSLETTER    = "Bad Mode (2nd Letter); A D I or P only (+ X Y & Z for Maths) (+ I V & G for Fillet)"
 PDT_ERR_BADMATHS      = "Not a Valid Mathematical Expression!"
 PDT_ERR_BADCOORDL     = "X Y & Z Not permitted in anything other than Maths Operations"
 PDT_ERR_BAD1VALS      = "Bad Command - 1 Value needed"
@@ -170,3 +171,4 @@ PDT_DES_FILLETRAD     = "Fillet Radius"
 PDT_DES_FILLETSEG     = "Number of Fillet Segments"
 PDT_DES_FILLETPROF    = "Fillet Profile"
 PDT_DES_FILLETVERTS   = "Use Vertices, or Edges, Set to False for Extruded Geometry"
+PDT_DES_FILLINT       = "Intersect & Fillet Two Selected Edges"