Fix T52007: Cancel bezier curve transform fails
authorCampbell Barton <ideasman42@gmail.com>
Mon, 10 Jul 2017 03:38:28 +0000 (13:38 +1000)
committerCampbell Barton <ideasman42@gmail.com>
Mon, 10 Jul 2017 03:38:28 +0000 (13:38 +1000)
Auto & aligned handles wouldn't restore to their correct locations.

Note that a more direct fix for the bug is possible
(storing the handle locations to restore on cancel).

But that still gives some odd behavior, see code-comments for details.

source/blender/editors/transform/transform_conversions.c

index b7a42121e927bc3c0ed5e4179a1322c8781cfd75..c15d11cdb6ee0baa3578a43957e4a34c7c778c3a 100644 (file)
@@ -1525,6 +1525,48 @@ static TransDataCurveHandleFlags *initTransDataCurveHandles(TransData *td, struc
        return hdata;
 }
 
+/**
+ * For the purpose of transform code we need to behave as if handles are selected,
+ * even when they aren't (see special case below).
+ */
+static int bezt_select_to_transform_triple_flag(
+        const BezTriple *bezt, const bool hide_handles)
+{
+       int flag = 0;
+
+       if (hide_handles) {
+               if (bezt->f2 & SELECT) {
+                       flag = (1 << 0) | (1 << 1) | (1 << 2);
+               }
+       }
+       else {
+               flag = (
+                       ((bezt->f1 & SELECT) ? (1 << 0) : 0) |
+                       ((bezt->f2 & SELECT) ? (1 << 1) : 0) |
+                       ((bezt->f3 & SELECT) ? (1 << 2) : 0)
+               );
+       }
+
+       /* Special case for auto & aligned handles:
+        * When a center point is being moved without the handles,
+        * leaving the handles stationary makes no sense and only causes strange behavior,
+        * where one handle is arbitrarily anchored, the other one is aligned and lengthened
+        * based on where the center point is moved. Also a bug when cancelling, see: T52007.
+        *
+        * A more 'correct' solution could be to store handle locations in 'TransDataCurveHandleFlags'.
+        * However that doesn't resolve odd behavior, so best transform the handles in this case.
+        */
+       if ((flag != ((1 << 0) | (1 << 1) | (1 << 2))) && (flag & (1 << 1))) {
+               if (ELEM(bezt->h1, HD_AUTO, HD_ALIGN) &&
+                   ELEM(bezt->h2, HD_AUTO, HD_ALIGN))
+               {
+                       flag = (1 << 0) | (1 << 1) | (1 << 2);
+               }
+       }
+
+       return flag;
+}
+
 static void createTransCurveVerts(TransInfo *t)
 {
        Curve *cu = t->obedit->data;
@@ -1542,22 +1584,22 @@ static void createTransCurveVerts(TransInfo *t)
        /* to be sure */
        if (cu->editnurb == NULL) return;
 
+#define SEL_F1 (1 << 0)
+#define SEL_F2 (1 << 1)
+#define SEL_F3 (1 << 2)
+
        /* count total of vertices, check identical as in 2nd loop for making transdata! */
        nurbs = BKE_curve_editNurbs_get(cu);
        for (nu = nurbs->first; nu; nu = nu->next) {
                if (nu->type == CU_BEZIER) {
                        for (a = 0, bezt = nu->bezt; a < nu->pntsu; a++, bezt++) {
                                if (bezt->hide == 0) {
-                                       if (hide_handles) {
-                                               if (bezt->f2 & SELECT) countsel += 3;
-                                               if (is_prop_edit) count += 3;
-                                       }
-                                       else {
-                                               if (bezt->f1 & SELECT) countsel++;
-                                               if (bezt->f2 & SELECT) countsel++;
-                                               if (bezt->f3 & SELECT) countsel++;
-                                               if (is_prop_edit) count += 3;
-                                       }
+                                       const int bezt_tx = bezt_select_to_transform_triple_flag(bezt, hide_handles);
+                                       if (bezt_tx & SEL_F1) { countsel++; }
+                                       if (bezt_tx & SEL_F2) { countsel++; }
+                                       if (bezt_tx & SEL_F3) { countsel++; }
+                                       if (is_prop_edit) count += 3;
+
                                }
                        }
                }
@@ -1608,10 +1650,10 @@ static void createTransCurveVerts(TransInfo *t)
                                                }
                                        }
 
-                                       if (is_prop_edit ||
-                                           ((bezt->f2 & SELECT) && hide_handles) ||
-                                           ((bezt->f1 & SELECT) && hide_handles == 0))
-                                       {
+                                       /* Elements that will be transform (not always a match to selection). */
+                                       const int bezt_tx = bezt_select_to_transform_triple_flag(bezt, hide_handles);
+
+                                       if (is_prop_edit || bezt_tx & SEL_F1) {
                                                copy_v3_v3(td->iloc, bezt->vec[0]);
                                                td->loc = bezt->vec[0];
                                                copy_v3_v3(td->center, bezt->vec[(hide_handles ||
@@ -1642,7 +1684,7 @@ static void createTransCurveVerts(TransInfo *t)
                                        }
 
                                        /* This is the Curve Point, the other two are handles */
-                                       if (is_prop_edit || (bezt->f2 & SELECT)) {
+                                       if (is_prop_edit || bezt_tx & SEL_F2) {
                                                copy_v3_v3(td->iloc, bezt->vec[1]);
                                                td->loc = bezt->vec[1];
                                                copy_v3_v3(td->center, td->loc);
@@ -1668,7 +1710,7 @@ static void createTransCurveVerts(TransInfo *t)
                                                        copy_m3_m3(td->axismtx, axismtx);
                                                }
 
-                                               if ((bezt->f1 & SELECT) == 0 && (bezt->f3 & SELECT) == 0)
+                                               if ((bezt_tx & SEL_F1) == 0 && (bezt_tx & SEL_F3) == 0)
                                                        /* If the middle is selected but the sides arnt, this is needed */
                                                        if (hdata == NULL) { /* if the handle was not saved by the previous handle */
                                                                hdata = initTransDataCurveHandles(td, bezt);
@@ -1678,10 +1720,7 @@ static void createTransCurveVerts(TransInfo *t)
                                                count++;
                                                tail++;
                                        }
-                                       if (is_prop_edit ||
-                                           ((bezt->f2 & SELECT) && hide_handles) ||
-                                           ((bezt->f3 & SELECT) && hide_handles == 0))
-                                       {
+                                       if (is_prop_edit || bezt_tx & SEL_F3) {
                                                copy_v3_v3(td->iloc, bezt->vec[2]);
                                                td->loc = bezt->vec[2];
                                                copy_v3_v3(td->center, bezt->vec[(hide_handles ||
@@ -1769,6 +1808,10 @@ static void createTransCurveVerts(TransInfo *t)
                                calc_distanceCurveVerts(head, tail - 1);
                }
        }
+
+#undef SEL_F1
+#undef SEL_F2
+#undef SEL_F3
 }
 
 /* ********************* lattice *************** */