Camera tracking: added depth object to Follow Track constraint

If this object is defined, object with Follow Track constraint would be
projected into surface of this depth object.
If object is not set or there's no projection onto it, projection plane
calculated based on original object position would be used.

This allows to make cheap facial mocap.

1 files changed, 33 insertions, 5 deletions

diff --git a/source/blender/blenkernel/intern/constraint.c b/source/blender/blenkernel/intern/constraint.c
index 878db6b3ed1..77a4a6a429c 100644
--- a/source/blender/blenkernel/intern/constraint.c
+++ b/source/blender/blenkernel/intern/constraint.c
@@ -41,6 +41,7 @@
 #include "BLI_blenlib.h"
 #include "BLI_math.h"
 #include "BLI_editVert.h"
+#include "BLI_kdopbvh.h"
 #include "BLI_utildefines.h"
 
 #include "DNA_armature_types.h"
@@ -64,6 +65,7 @@
 #include "BKE_anim.h" /* for the curve calculation part */
 #include "BKE_armature.h"
 #include "BKE_blender.h"
+#include "BKE_bvhutils.h"
 #include "BKE_camera.h"
 #include "BKE_constraint.h"
 #include "BKE_displist.h"
@@ -3950,6 +3952,7 @@ static void followtrack_id_looper (bConstraint *con, ConstraintIDFunc func, void
 	
 	func(con, (ID**)&data->clip, userdata);
 	func(con, (ID**)&data->camera, userdata);
+	func(con, (ID**)&data->depth_ob, userdata);
 }
 
 static void followtrack_evaluate (bConstraint *con, bConstraintOb *cob, ListBase *UNUSED(targets))
@@ -3985,7 +3988,6 @@ static void followtrack_evaluate (bConstraint *con, bConstraintOb *cob, ListBase
 
 	if (data->flag & FOLLOWTRACK_USE_3D_POSITION) {
 		if (track->flag & TRACK_HAS_BUNDLE) {
-			MovieTracking *tracking= &clip->tracking;
 			float obmat[4][4], mat[4][4];
 
 			copy_m4_m4(obmat, cob->matrix);
@@ -4008,9 +4010,8 @@ static void followtrack_evaluate (bConstraint *con, bConstraintOb *cob, ListBase
 				translate_m4(cob->matrix, track->bundle_pos[0], track->bundle_pos[1], track->bundle_pos[2]);
 			}
 		}
-	} 
+	}
 	else {
-		MovieClipUser user;
 		MovieTrackingMarker *marker;
 		float vec[3], disp[3], axis[3], mat[4][4];
 		float aspect= (scene->r.xsch*scene->r.xasp) / (scene->r.ysch*scene->r.yasp);
@@ -4035,8 +4036,7 @@ static void followtrack_evaluate (bConstraint *con, bConstraintOb *cob, ListBase
 			CameraParams params;
 			float pos[2], rmat[4][4];
 
-			user.framenr= scene->r.cfra;
-			marker= BKE_tracking_get_marker(track, user.framenr);
+			marker= BKE_tracking_get_marker(track, scene->r.cfra);
 
 			add_v2_v2v2(pos, marker->pos, track->offset);
 
@@ -4078,6 +4078,34 @@ static void followtrack_evaluate (bConstraint *con, bConstraintOb *cob, ListBase
 
 				copy_v3_v3(cob->matrix[3], disp);
 			}
+
+			if(data->depth_ob && data->depth_ob->derivedFinal) {
+				Object *depth_ob= data->depth_ob;
+				BVHTreeFromMesh treeData= NULL_BVHTreeFromMesh;
+				BVHTreeRayHit hit;
+				float ray_start[3], ray_end[3], ray_nor[3], imat[4][4];
+				int result;
+
+				invert_m4_m4(imat, depth_ob->obmat);
+
+				mul_v3_m4v3(ray_start, imat, camob->obmat[3]);
+				mul_v3_m4v3(ray_end, imat, cob->matrix[3]);
+
+				sub_v3_v3v3(ray_nor, ray_end, ray_start);
+
+				bvhtree_from_mesh_faces(&treeData, depth_ob->derivedFinal, 0.0f, 4, 6);
+
+				hit.dist= FLT_MAX;
+				hit.index= -1;
+
+				result= BLI_bvhtree_ray_cast(treeData.tree, ray_start, ray_nor, 0.0f, &hit, treeData.raycast_callback, &treeData);
+
+				if(result != -1) {
+					mul_v3_m4v3(cob->matrix[3], depth_ob->obmat, hit.co);
+				}
+
+				free_bvhtree_from_mesh(&treeData);
+			}
 		}
 	}
 }