Fix T76417: Gpencil Join did not supported weight join

Now the operator keep the weights of all strokes when joining.

1 files changed, 21 insertions, 6 deletions

diff --git a/source/blender/editors/gpencil/gpencil_edit.c b/source/blender/editors/gpencil/gpencil_edit.c
index 4a4ade4e98f..6f109fe4fa4 100644
--- a/source/blender/editors/gpencil/gpencil_edit.c
+++ b/source/blender/editors/gpencil/gpencil_edit.c
@@ -3186,6 +3186,7 @@ static void gpencil_flip_stroke(bGPDstroke *gps)
 
 /* Helper: copy point between strokes */
 static void gpencil_stroke_copy_point(bGPDstroke *gps,
+                                      MDeformVert *dvert,
                                       bGPDspoint *point,
                                       int idx,
                                       const float delta[3],
@@ -3199,6 +3200,13 @@ static void gpencil_stroke_copy_point(bGPDstroke *gps,
   if (gps->dvert != NULL) {
     gps->dvert = MEM_reallocN(gps->dvert, sizeof(MDeformVert) * (gps->totpoints + 1));
   }
+  else {
+    /* If destination has weight add weight to origin. */
+    if (dvert != NULL) {
+      gps->dvert = MEM_callocN(sizeof(MDeformVert) * (gps->totpoints + 1), __func__);
+    }
+  }
+
   gps->totpoints++;
   newpoint = &gps->points[gps->totpoints - 1];
 
@@ -3212,11 +3220,16 @@ static void gpencil_stroke_copy_point(bGPDstroke *gps,
   copy_v4_v4(newpoint->vert_color, point->vert_color);
 
   if (gps->dvert != NULL) {
-    MDeformVert *dvert = &gps->dvert[idx];
     MDeformVert *newdvert = &gps->dvert[gps->totpoints - 1];
 
-    newdvert->totweight = dvert->totweight;
-    newdvert->dw = MEM_dupallocN(dvert->dw);
+    if (dvert != NULL) {
+      newdvert->totweight = dvert->totweight;
+      newdvert->dw = MEM_dupallocN(dvert->dw);
+    }
+    else {
+      newdvert->totweight = 0;
+      newdvert->dw = NULL;
+    }
   }
 }
 
@@ -3267,16 +3280,18 @@ static void gpencil_stroke_join_strokes(bGPDstroke *gps_a,
     /* 1st: add one tail point to start invisible area */
     point = gps_a->points[gps_a->totpoints - 1];
     deltatime = point.time;
-    gpencil_stroke_copy_point(gps_a, &point, gps_a->totpoints - 1, delta, 0.0f, 0.0f, 0.0f);
+
+    gpencil_stroke_copy_point(gps_a, NULL, &point, gps_a->totpoints - 1, delta, 0.0f, 0.0f, 0.0f);
 
     /* 2nd: add one head point to finish invisible area */
     point = gps_b->points[0];
-    gpencil_stroke_copy_point(gps_a, &point, 0, delta, 0.0f, 0.0f, deltatime);
+    gpencil_stroke_copy_point(gps_a, NULL, &point, 0, delta, 0.0f, 0.0f, deltatime);
   }
 
   /* 3rd: add all points */
   for (i = 0, pt = gps_b->points; i < gps_b->totpoints && pt; i++, pt++) {
-    gpencil_stroke_copy_point(gps_a, pt, i, delta, pt->pressure, pt->strength, deltatime);
+    MDeformVert *dvert = (gps_b->dvert) ? &gps_b->dvert[i] : NULL;
+    gpencil_stroke_copy_point(gps_a, dvert, pt, i, delta, pt->pressure, pt->strength, deltatime);
   }
 }