fix for crash when moving frames about in the node space, was possible to move a node into its own child frame (causing recursive parent loop).

also some minor code cleanup.

source/blender/blenkernel/BKE_node.h

@@ -359,6 +359,7 @@ void            nodeInternalRelink(struct bNodeTree *ntree, struct bNode *node);
 
 void            nodeToView(struct bNode *node, float x, float y, float *rx, float *ry);
 void            nodeFromView(struct bNode *node, float x, float y, float *rx, float *ry);
+int             nodeAttachNodeCheck(struct bNode *node, struct bNode *parent);
 void            nodeAttachNode(struct bNode *node, struct bNode *parent);
 void            nodeDetachNode(struct bNode *node);
 

source/blender/blenkernel/intern/node.c

@@ -592,9 +592,25 @@ void nodeFromView(bNode *node, float x, float y, float *rx, float *ry)
 	}
 }
 
+int nodeAttachNodeCheck(bNode *node, bNode *parent)
+{
+	bNode *parent_recurse;
+	for (parent_recurse = node; parent_recurse; parent_recurse = parent_recurse->parent) {
+		if (parent_recurse == parent) {
+			return TRUE;
+		}
+	}
+
+	return FALSE;
+}
+
 void nodeAttachNode(bNode *node, bNode *parent)
 {
 	float locx, locy;
+
+	BLI_assert(parent->type == NODE_FRAME);
+	BLI_assert(nodeAttachNodeCheck(parent, node) == FALSE);
+
 	nodeToView(node, 0.0f, 0.0f, &locx, &locy);
 	
 	node->parent = parent;
@@ -607,6 +623,9 @@ void nodeDetachNode(struct bNode *node)
 	float locx, locy;
 	
 	if (node->parent) {
+
+		BLI_assert(node->parent->type == NODE_FRAME);
+
 		/* transform to view space */
 		nodeToView(node, 0.0f, 0.0f, &locx, &locy);
 		node->locx = locx;

source/blender/editors/space_node/drawnode.c

@@ -996,9 +996,7 @@ static void node_draw_frame(const bContext *C, ARegion *ar, SpaceNode *snode, bN
 	float alpha;
 	
 	/* skip if out of view */
-	if (node->totr.xmax < ar->v2d.cur.xmin || node->totr.xmin > ar->v2d.cur.xmax ||
-	    node->totr.ymax < ar->v2d.cur.ymin || node->totr.ymin > ar->v2d.cur.ymax) {
-		
+	if (BLI_rctf_isect(&node->totr, &ar->v2d.cur, NULL) == FALSE) {
 		uiEndBlock(C, node->block);
 		node->block = NULL;
 		return;

source/blender/editors/space_node/node_draw.c

@@ -681,9 +681,7 @@ static void node_draw_basis(const bContext *C, ARegion *ar, SpaceNode *snode, bN
 		nodeShaderSynchronizeID(node, 0);
 	
 	/* skip if out of view */
-	if (node->totr.xmax < ar->v2d.cur.xmin || node->totr.xmin > ar->v2d.cur.xmax ||
-	    node->totr.ymax < ar->v2d.cur.ymin || node->totr.ymin > ar->v2d.cur.ymax)
-	{
+	if (BLI_rctf_isect(&node->totr, &ar->v2d.cur, NULL) == FALSE) {
 		uiEndBlock(C, node->block);
 		node->block = NULL;
 		return;

source/blender/editors/space_node/node_edit.c

@@ -762,7 +762,7 @@ static void edit_node_properties_get(wmOperator *op, bNodeTree *ntree, bNode **r
 /* ************************** Node generic ************** */
 
 /* is rct in visible part of node? */
-static bNode *visible_node(SpaceNode *snode, rctf *rct)
+static bNode *visible_node(SpaceNode *snode, const rctf *rct)
 {
 	bNode *node;
 	

source/blender/editors/space_node/node_relationships.c

@@ -1147,17 +1147,26 @@ static int node_attach_exec(bContext *C, wmOperator *UNUSED(op))
 		for (node = ntree->nodes.last; node; node = node->prev) {
 			if (node->flag & NODE_SELECT) {
 				if (node->parent == NULL) {
-					/* attach all unparented nodes */
-					nodeAttachNode(node, frame);
+					/* disallow moving a parent into its child */
+					if (nodeAttachNodeCheck(frame, node) == FALSE) {
+						/* attach all unparented nodes */
+						nodeAttachNode(node, frame);
+					}
 				}
 				else {
 					/* attach nodes which share parent with the frame */
-					for (parent = frame->parent; parent; parent = parent->parent)
-						if (parent == node->parent)
+					for (parent = frame->parent; parent; parent = parent->parent) {
+						if (parent == node->parent) {
 							break;
+						}
+					}
+
 					if (parent) {
-						nodeDetachNode(node);
-						nodeAttachNode(node, frame);
+						/* disallow moving a parent into its child */
+						if (nodeAttachNodeCheck(frame, node) == FALSE) {
+							nodeDetachNode(node);
+							nodeAttachNode(node, frame);
+						}
 					}
 				}
 			}

source/blender/editors/transform/transform.h

@@ -666,7 +666,7 @@ int initTransInfo(struct bContext *C, TransInfo *t, struct wmOperator *op, struc
 void postTrans (struct bContext *C, TransInfo *t);
 void resetTransRestrictions(TransInfo *t);
 
-void drawLine(TransInfo *t, float *center, float *dir, char axis, short options);
+void drawLine(TransInfo *t, const float center[3], const float dir[3], char axis, short options);
 
 void drawNonPropEdge(const struct bContext *C, TransInfo *t);
 

source/blender/editors/transform/transform_generics.c

@@ -923,7 +923,7 @@ void recalcData(TransInfo *t)
 	}
 }
 
-void drawLine(TransInfo *t, float *center, float *dir, char axis, short options)
+void drawLine(TransInfo *t, const float center[3], const float dir[3], char axis, short options)
 {
 	float v1[3], v2[3], v3[3];
 	unsigned char col[3], col2[3];
@@ -1017,15 +1017,10 @@ int initTransInfo(bContext *C, TransInfo *t, wmOperator *op, wmEvent *event)
 	t->total            = 0;
 	
 	t->val = 0.0f;
-	
-	t->vec[0]           =
-	    t->vec[1]       =
-	        t->vec[2]       = 0.0f;
 
-	t->center[0]        =
-	    t->center[1]    =
-	        t->center[2]    = 0.0f;
-	
+	zero_v3(t->vec);
+	zero_v3(t->center);
+
 	unit_m3(t->mat);
 	
 	/* if there's an event, we're modal */