2 New tools, 'Loop to region' and 'Region to loop'

-> Loop to Region
Examines the current set of selected edges and seperates them into groups
 of 'loops' that each bisect the mesh into two parts. Then for each loop it
selects the smaller 'half' of the mesh.

Example images:
http://www.umsl.edu/~gcbq44/looptoregion2a.jpg
http://www.umsl.edu/~gcbq44/looptoregion2b.jpg

This tool handles multiple loops fine as is shown by these images:
http://www.umsl.edu/~gcbq44/looptoregion1a.jpg
http://www.umsl.edu/~gcbq44/looptoregion1b.jpg

Furthermore it handles 'holes' just fine as well:
http://www.umsl.edu/~gcbq44/looptoregion3a.jpg
http://www.umsl.edu/~gcbq44/looptoregion3b.jpg

-> Region to Loop

This is the 'logical inverse' of loop to region.

Example:
http://www.umsl.edu/~gcbq44/regiontoloop1a.jpg
http://www.umsl.edu/~gcbq44/regiontoloop1b.jpg

Both features can be accessed by the 'Edge Menu' in EditMode (CTRL-E).

1 files changed, 184 insertions, 2 deletions

diff --git a/source/blender/src/editmesh_tools.c b/source/blender/src/editmesh_tools.c
index f5237abc59e..85823246194 100644
--- a/source/blender/src/editmesh_tools.c
+++ b/source/blender/src/editmesh_tools.c
@@ -6242,9 +6242,8 @@ void pathselect(void)
 			MEM_freeN(cost);
 			MEM_freeN(previous);
 			BLI_heap_free(heap, NULL);
-			
 			EM_select_flush();
-			
+			countall();
 		}
 	}
 	else{
@@ -6252,3 +6251,186 @@ void pathselect(void)
 		return;
 	}
 }
+
+void region_to_loop(void)
+{
+	EditEdge *eed;
+	EditFace *efa;
+	
+	if(G.totfacesel){
+		for(eed=G.editMesh->edges.first; eed; eed=eed->next) eed->f1 = 0;
+		
+		for(efa=G.editMesh->faces.first; efa; efa=efa->next){
+			if(efa->f&SELECT){
+				efa->e1->f1++;
+				efa->e2->f1++;
+				efa->e3->f1++;
+				if(efa->e4)
+					efa->e4->f1++;
+			}
+		}
+		
+		EM_clear_flag_all(SELECT);
+		
+		for(eed=G.editMesh->edges.first; eed; eed=eed->next){
+			if(eed->f1 == 1) EM_select_edge(eed, 1);
+		}
+		
+		G.scene->selectmode = SCE_SELECT_EDGE;
+		EM_selectmode_set();
+		countall();
+		BIF_undo_push("Face Region to Edge Loop");
+
+	}
+}
+
+static int validate_loop(Collection *edgecollection)
+{
+	EditEdge *eed;
+	EditFace *efa;
+	CollectedEdge *curredge;
+	
+	/*1st test*/
+	for(curredge = (CollectedEdge*)edgecollection->collectionbase.first; curredge; curredge=curredge->next){
+		curredge->eed->v1->f1 = 0;
+		curredge->eed->v2->f1 = 0;
+	}
+	for(curredge = (CollectedEdge*)edgecollection->collectionbase.first; curredge; curredge=curredge->next){
+		curredge->eed->v1->f1++;
+		curredge->eed->v2->f1++;
+	}
+	for(curredge = (CollectedEdge*)edgecollection->collectionbase.first; curredge; curredge=curredge->next){
+		if(curredge->eed->v1->f1 > 2) return(0); else
+		if(curredge->eed->v2->f1 > 2) return(0);
+	}
+	
+	/*2nd test*/
+	for(eed = G.editMesh->edges.first; eed; eed=eed->next) eed->f1 = 0;
+	for(efa=G.editMesh->faces.first; efa; efa=efa->next){
+		efa->e1->f1++;
+		efa->e2->f1++;
+		efa->e3->f1++;
+		if(efa->e4) efa->e4->f1++;
+	}
+	for(curredge = (CollectedEdge*)edgecollection->collectionbase.first; curredge; curredge=curredge->next){
+		if(curredge->eed->f1 > 2) return(0);
+	}
+	return(1);
+}
+
+static int loop_bisect(Collection *edgecollection){
+	
+	EditFace *efa, *sf1, *sf2;
+	EditEdge *eed, *sed;
+	CollectedEdge *curredge;
+	int totsf1, totsf2, unbalanced,balancededges;
+	
+	for(eed=G.editMesh->edges.first; eed; eed=eed->next) eed->f1 = eed->f2 = 0;
+	for(efa=G.editMesh->faces.first; efa; efa=efa->next) efa->f1 = 0;	
+	
+	for(curredge = (CollectedEdge*)edgecollection->collectionbase.first; curredge; curredge=curredge->next) curredge->eed->f1 = 1;
+	
+	sf1 = sf2 = NULL;
+	sed = ((CollectedEdge*)edgecollection->collectionbase.first)->eed;
+	
+	for(efa=G.editMesh->faces.first; efa; efa=efa->next){
+		if(sf2) break;
+		else if(sf1){
+			if(efa->e1 == sed || efa->e2 == sed || efa->e3 == sed || ( (efa->e4) ? efa->e4 == sed : 0) ) sf2 = efa;
+		}
+		else{
+			if(efa->e1 == sed || efa->e2 == sed || efa->e3 == sed || ( (efa->e4) ? efa->e4 == sed : 0) ) sf1 = efa;
+		}
+	}
+	
+	if(!(sf1->e1->f1)) sf1->e1->f2 = 1;
+	if(!(sf1->e2->f1)) sf1->e2->f2 = 1;
+	if(!(sf1->e3->f1)) sf1->e3->f2 = 1;
+	if(sf1->e4 && !(sf1->e4->f1)) sf1->e4->f2 = 1;
+	sf1->f1 = 1;
+	totsf1 = 1;
+	
+	if(!(sf2->e1->f1)) sf2->e1->f2 = 2;
+	if(!(sf2->e2->f1)) sf2->e2->f2 = 2;
+	if(!(sf2->e3->f1)) sf2->e3->f2 = 2;
+	if(sf2->e4 && !(sf2->e4->f1)) sf2->e4->f2 = 2;
+	sf2->f1 = 2;
+	totsf2 = 1;
+	
+	/*do sf1*/
+	unbalanced = 1;
+	while(unbalanced){
+		unbalanced = 0;
+		for(efa=G.editMesh->faces.first; efa; efa=efa->next){
+			balancededges = 0;
+			if(efa->f1 == 0){
+				if(efa->e1->f2 == 1 || efa->e2->f2 == 1 || efa->e3->f2 == 1 || ( (efa->e4) ? efa->e4->f2 == 1 : 0) ){
+					balancededges += efa->e1->f2 = (efa->e1->f1) ? 0 : 1;
+					balancededges += efa->e2->f2 = (efa->e2->f1) ? 0 : 1;
+					balancededges += efa->e3->f2 = (efa->e3->f1) ? 0 : 1;
+					if(efa->e4) balancededges += efa->e4->f2 = (efa->e4->f1) ? 0 : 1;
+					if(balancededges){
+						unbalanced = 1;
+						efa->f1 = 1;
+						totsf1++;
+					}
+				}
+			}
+		}
+	}
+	
+	/*do sf2*/
+	unbalanced = 1;
+	while(unbalanced){
+		unbalanced = 0;
+		for(efa=G.editMesh->faces.first; efa; efa=efa->next){
+			balancededges = 0;
+			if(efa->f1 == 0){
+				if(efa->e1->f2 == 2 || efa->e2->f2 == 2 || efa->e3->f2 == 2 || ( (efa->e4) ? efa->e4->f2 == 2 : 0) ){
+					balancededges += efa->e1->f2 = (efa->e1->f1) ? 0 : 2;
+					balancededges += efa->e2->f2 = (efa->e2->f1) ? 0 : 2;
+					balancededges += efa->e3->f2 = (efa->e3->f1) ? 0 : 2;
+					if(efa->e4) balancededges += efa->e4->f2 = (efa->e4->f1) ? 0 : 2;
+					if(balancededges){
+						unbalanced = 1;
+						efa->f1 = 2;
+						totsf2++;
+					}
+				}
+			}
+		}
+	}
+		
+	if(totsf1 < totsf2) return(1);
+	else return(2);
+}
+
+void loop_to_region(void)
+{
+	EditFace *efa;
+	ListBase allcollections={NULL,NULL};
+	Collection *edgecollection;
+	int testflag;
+	
+	build_edgecollection(&allcollections);
+	
+	for(edgecollection = (Collection *)allcollections.first; edgecollection; edgecollection=edgecollection->next){
+		if(validate_loop(edgecollection)){
+			testflag = loop_bisect(edgecollection);
+			for(efa=G.editMesh->faces.first; efa; efa=efa->next){
+				if(efa->f1 == testflag){
+					if(efa->f&SELECT) EM_select_face(efa, 0);
+					else EM_select_face(efa,1);
+				}
+			}
+		}
+	}
+	
+	for(efa=G.editMesh->faces.first; efa; efa=efa->next){ /*fix this*/
+		if(efa->f&SELECT) EM_select_face(efa,1);
+	}
+	
+	countall();
+	freecollections(&allcollections);
+	BIF_undo_push("Edge Loop to Face Region");
+}
\ No newline at end of file