[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [11357] trunk/blender/source/blender/src/ transform_conversions.c: Bugfixes for Transform (related to Constraints):

[Joshua Leung]

Revision: 11357
          http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=11357
Author:   aligorith
Date:     2007-07-24 13:39:40 +0200 (Tue, 24 Jul 2007)

Log Message:
-----------
Bugfixes for Transform (related to Constraints):
* Reverting a previous commit where I wrongly assumed that the code was not doing things the right way. This makes a few cases work better normally again.
* Object-level Transforms should now perform normally again. Now, transforms are only get inverse-corrected for constraints if certain constraints are the first 'active' constraint. 
* PoseBone-level Transforms still need to be fixed, although I might have done a few tweaks here.

Modified Paths:
--------------
    trunk/blender/source/blender/src/transform_conversions.c

Modified: trunk/blender/source/blender/src/transform_conversions.c
===================================================================
--- trunk/blender/source/blender/src/transform_conversions.c	2007-07-24 10:24:25 UTC (rev 11356)
+++ trunk/blender/source/blender/src/transform_conversions.c	2007-07-24 11:39:40 UTC (rev 11357)
@@ -2040,6 +2040,36 @@
 
 /* *************************** Object Transform data ******************* */
 
+/* Little helper function for ObjectToTransData used to give certain
+ * constraints (ChildOf, FollowPath, and others that may be added)
+ * inverse corrections for transform, so that they aren't in CrazySpace.
+ * These particular constraints benefit from this, but others don't, hence
+ * this semi-hack ;-)    - Aligorith
+ */
+static short ob_constraints_needinv(Object *ob)
+{
+	bConstraint *con;
+	
+	/* loop through constraints, checking if there's one of the mentioned 
+	 * constraints needing special crazyspace corrections
+	 */
+	if (ob && ob->constraints.first) {
+		for (con= ob->constraints.first; con; con=con->next) {
+			/* only consider constraint if it is enabled, and has influence on result */
+			if ((con->flag & CONSTRAINT_DISABLE)==0 && (con->enforce!=0.0)) {
+				/* (affirmative) returns for specific constraints here... */
+				if (con->type == CONSTRAINT_TYPE_CHILDOF) return 1;
+				if (con->type == CONSTRAINT_TYPE_FOLLOWPATH) return 1;
+				if (con->type == CONSTRAINT_TYPE_CLAMPTO) return 1;
+			}
+		}
+	}
+	
+	/* no appropriate candidates found */
+	return 0;
+}
+
+/* transcribe given object into TransData for Transforming */
 static void ObjectToTransData(TransData *td, Object *ob) 
 {
 	float obmtx[3][3];
@@ -2065,19 +2095,22 @@
 
 	VECCOPY(td->center, ob->obmat[3]);
 
-	if (ob->parent || ob->constraints.first)
-	{
+	/* is there a need to set the global<->data space conversion matrices? */
+	if (ob->parent || ob_constraints_needinv(ob)) {
 		float totmat[3][3], obinv[3][3];
 		
-		/* get the effect of parenting, and/or constraints */
+		/* Get the effect of parenting, and/or certain constraints.
+		 * NOTE: some Constraints, and also Tracking should never get this
+		 *		done, as it doesn't work well.
+		 */
 		object_to_mat3(ob, obmtx);
 		Mat3CpyMat4(totmat, ob->obmat);
-		Mat3Inv(obinv, obmtx);
-		Mat3MulMat3(td->smtx, totmat, obinv);
+		Mat3Inv(obinv, totmat);
+		Mat3MulMat3(td->smtx, obmtx, obinv);
 		Mat3Inv(td->mtx, td->smtx);
 	}
-	else
-	{
+	else {
+		/* no conversion to/from dataspace */
 		Mat3One(td->smtx);
 		Mat3One(td->mtx);
 	}