Add "lock point where dragged" constraint, in either 2d or 3d.

And call the cubic things splines, not segments, since that's what
they are now.

[git-p4: depot-paths = "//depot/solvespace/": change = 2135]

constraint.cpp

@@ -36,6 +36,7 @@ char *Constraint::DescriptionString(void) {
         case EQUAL_RADIUS:      s = "eq-radius"; break;
         case EQUAL_ANGLE:       s = "eq-angle"; break;
         case EQUAL_LINE_ARC_LEN:s = "eq-line-len-arc-len"; break;
+        case WHERE_DRAGGED:     s = "lock-where-dragged"; break;
         case COMMENT:           s = "comment"; break;
         default:                s = "???"; break;
     }
@@ -646,6 +647,19 @@ void Constraint::MenuConstrain(int id) {
             AddConstraint(&c);
             break;
 
+        case GraphicsWindow::MNU_WHERE_DRAGGED:
+            if(gs.points == 1 && gs.n == 1) {
+                c.type = WHERE_DRAGGED;
+                c.ptA = gs.point[0];
+            } else {
+                Error("Bad selection for lock point where dragged constraint. "
+                      "This constraint can apply to:\n\n"
+                      "    * a point\n");
+                return;
+            }
+            AddConstraint(&c);
+            break;
+
         case GraphicsWindow::MNU_COMMENT:
             SS.GW.pending.operation = GraphicsWindow::MNU_COMMENT;
             SS.GW.pending.description = "click center of comment text";

constrainteq.cpp

@@ -690,6 +690,24 @@ void ConstraintBase::GenerateReal(IdList<Equation,hEquation> *l) {
             break;
         }
 
+        case WHERE_DRAGGED: {
+            EntityBase *ep = SK.GetEntity(ptA);
+            if(workplane.v == EntityBase::FREE_IN_3D.v) {
+                ExprVector ev = ep->PointGetExprs();
+                Vector v = ep->PointGetNum();
+
+                AddEq(l, ev.x->Minus(Expr::From(v.x)), 0);
+                AddEq(l, ev.y->Minus(Expr::From(v.y)), 1);
+                AddEq(l, ev.z->Minus(Expr::From(v.z)), 2);
+            } else {
+                Expr *u, *v;
+                ep->PointGetExprsInWorkplane(workplane, &u, &v);
+                AddEq(l, u->Minus(Expr::From(u->Eval())), 0);
+                AddEq(l, v->Minus(Expr::From(v->Eval())), 1);
+            }
+            break;
+        }
+
         case COMMENT:
             break;
 

describescreen.cpp

@@ -284,10 +284,13 @@ void TextWindow::DescribeSelection(void) {
             Printf(true,  "      distance = %Fi%s", SS.MmToString(d));
         }
     } else if(gs.n == 0 && gs.stylables > 0) {
-        Printf(true, "%FtSELECTED:%E comment text");
+        Printf(false, "%FtSELECTED:%E comment text");
+    } else if(gs.n == 0 && gs.constraints == 1) {
+        Printf(false, "%FtSELECTED:%E %s",
+            SK.GetConstraint(gs.constraint[0])->DescriptionString());
     } else {
         int n = SS.GW.selection.n;
-        Printf(true, "%FtSELECTED:%E %d item%s", n, n == 1 ? "" : "s");
+        Printf(false, "%FtSELECTED:%E %d item%s", n, n == 1 ? "" : "s");
     }
 
     if(shown.screen == SCREEN_STYLE_INFO && 

drawconstraint.cpp

@@ -601,6 +601,25 @@ void Constraint::DrawOrGetDistance(Vector *labelPos) {
             break;
         }
 
+        case WHERE_DRAGGED: {
+            Vector p = SK.GetEntity(ptA)->PointGetNum(),
+                   u = p.Plus(gu.WithMagnitude(8/SS.GW.scale)).Plus(
+                              gr.WithMagnitude(8/SS.GW.scale)),
+                   uu = u.Minus(gu.WithMagnitude(5/SS.GW.scale)),
+                   ur = u.Minus(gr.WithMagnitude(5/SS.GW.scale));
+            // Draw four little crop marks, uniformly spaced (by ninety
+            // degree rotations) around the point.
+            int i;
+            for(i = 0; i < 4; i++) {
+                LineDrawOrGetDistance(u, uu);
+                LineDrawOrGetDistance(u, ur);
+                u = u.RotatedAbout(p, gn, PI/2);
+                ur = ur.RotatedAbout(p, gn, PI/2);
+                uu = uu.RotatedAbout(p, gn, PI/2);
+            }
+            break;
+        }
+
         case SAME_ORIENTATION: {
             for(int i = 0; i < 2; i++) {
                 Entity *e = SK.GetEntity(i == 0 ? entityA : entityB);

graphicswin.cpp

@@ -92,7 +92,7 @@ const GraphicsWindow::MenuEntry GraphicsWindow::menu[] = {
 { 1, "&Rectangle\tR",                       MNU_RECTANGLE,      'R',    mReq  },
 { 1, "&Circle\tC",                          MNU_CIRCLE,         'C',    mReq  },
 { 1, "&Arc of a Circle\tA",                 MNU_ARC,            'A',    mReq  },
-{ 1, "&Bezier Cubic Segment\tB",            MNU_CUBIC,          'B',    mReq  },
+{ 1, "&Bezier Cubic Spline\tB",             MNU_CUBIC,          'B',    mReq  },
 { 1, NULL,                                  0,                          NULL  },
 { 1, "&Text in TrueType Font\tT",           MNU_TTF_TEXT,       'T',    mReq  },
 { 1, NULL,                                  0,                          NULL  },
@@ -116,6 +116,7 @@ const GraphicsWindow::MenuEntry GraphicsWindow::menu[] = {
 { 1, "Para&llel / Tangent\tL",              MNU_PARALLEL,       'L',    mCon  },
 { 1, "&Perpendicular\t[",                   MNU_PERPENDICULAR,  '[',    mCon  },
 { 1, "Same Orient&ation\tX",                MNU_ORIENTED_SAME,  'X',    mCon  },
+{ 1, "Lock Point Where &Dragged\t]",        MNU_WHERE_DRAGGED,  ']',    mCon  },
 { 1, NULL,                                  0,                          NULL  },
 { 1, "Comment\t;",                          MNU_COMMENT,        ';',    mCon  },
 

sketch.h

@@ -545,6 +545,7 @@ public:
     static const int ARC_LINE_TANGENT   = 123;
     static const int CUBIC_LINE_TANGENT = 124;
     static const int EQUAL_RADIUS       = 130;
+    static const int WHERE_DRAGGED      = 200;
 
     static const int COMMENT            = 1000;
 

toolbar.cpp

@@ -11,7 +11,7 @@ static const struct {
     { Icon_rectangle,       GraphicsWindow::MNU_RECTANGLE,      "Sketch rectangle"                                  },
     { Icon_circle,          GraphicsWindow::MNU_CIRCLE,         "Sketch circle"                                     },
     { Icon_arc,             GraphicsWindow::MNU_ARC,            "Sketch arc, or tangent arc at selected point"      },
-    { Icon_bezier,          GraphicsWindow::MNU_CUBIC,          "Sketch cubic Bezier section"                       },
+    { Icon_bezier,          GraphicsWindow::MNU_CUBIC,          "Sketch cubic Bezier spline"                        },
     { Icon_point,           GraphicsWindow::MNU_DATUM_POINT,    "Sketch datum point"                                },
     { Icon_construction,    GraphicsWindow::MNU_CONSTRUCTION,   "Toggle construction"                               },
     { Icon_trim,            GraphicsWindow::MNU_SPLIT_CURVES,   "Split lines / curves where they intersect"         },

ui.h

@@ -363,6 +363,7 @@ public:
         MNU_PARALLEL,
         MNU_PERPENDICULAR,
         MNU_ORIENTED_SAME,
+        MNU_WHERE_DRAGGED,
         MNU_COMMENT,
         // Analyze
         MNU_VOLUME,

wishlist.txt

@@ -1,7 +1,6 @@
 add checked/unchecked checkbox and radio button
 fix bug with rotation in plane where green line stays displayed
-lock point where dragged constraint
+expose transformed point stuff in library
-expose transformed point stuff in library, and email McNeel
 
 -----
 rounding, as a special group