Seperated out some functionality into 3 new functions.

EM_editselection_center
EM_editselection_normal
EM_editselection_plane
These functions are used by the manipulator to get data from an editselection. regardless of weather its a face/edge/vert.

1 files changed, 118 insertions, 0 deletions

diff --git a/source/blender/src/editmesh_lib.c b/source/blender/src/editmesh_lib.c
index bf64fdc34cc..974519a2844 100644
--- a/source/blender/src/editmesh_lib.c
+++ b/source/blender/src/editmesh_lib.c
@@ -136,6 +136,124 @@ static void EM_strip_selections(void)
 	}
 }
 
+/* generic way to get data from an EditSelection type 
+These functions were written to be used by the Modifier widget when in Rotate about active mode,
+but can be used anywhere.
+EM_editselection_center
+EM_editselection_normal
+EM_editselection_plane
+*/
+void EM_editselection_center(float *center, EditSelection *ese)
+{
+	if (ese->type==EDITVERT) {
+		EditVert *eve= ese->data;
+		VecCopyf(center, eve->co);
+	} else if (ese->type==EDITEDGE) {
+		EditEdge *eed= ese->data;
+		VecAddf(center, eed->v1->co, eed->v2->co);
+		VecMulf(center, 0.5);
+	} else if (ese->type==EDITFACE) {
+		EditFace *efa= ese->data;
+		VecCopyf(center, efa->cent);
+	}
+}
+
+void EM_editselection_normal(float *normal, EditSelection *ese)
+{
+	if (ese->type==EDITVERT) {
+		EditVert *eve= ese->data;
+		VecCopyf(normal, eve->no);
+	} else if (ese->type==EDITEDGE) {
+		EditEdge *eed= ese->data;
+		float plane[3]; /* need a plane to correct the normal */
+		float vec[3]; /* temp vec storage */
+		
+		VecAddf(normal, eed->v1->no, eed->v2->no);
+		VecSubf(plane, eed->v2->co, eed->v1->co);
+		
+		/* the 2 vertex normals will be close but not at rightangles to the edge
+		for rotate about edge we want them to be at right angles, so we need to
+		do some extra colculation to correct the vert normals,
+		we need the plane for this */
+		Crossf(vec, normal, plane);
+		Crossf(normal, plane, vec); 
+		Normalise(normal);
+		
+	} else if (ese->type==EDITFACE) {
+		EditFace *efa= ese->data;
+		VecCopyf(normal, efa->n);
+	}
+}
+
+/* Calculate a plane that is rightangles to the edge/vert/faces normal
+also make the plane run allong an axis that is related to the geometry,
+because this is used for the manipulators Y axis.*/
+void EM_editselection_plane(float *plane, EditSelection *ese)
+{
+	if (ese->type==EDITVERT) {
+		EditVert *eve= ese->data;
+		float vec[3]={0,0,0};
+		
+		if (ese->prev) { /*use previously selected data to make a usefull vertex plane */
+			EM_editselection_center(vec, ese->prev);
+			VecSubf(plane, eve->co, vec);
+		} else {
+			/* make a fake  plane thats at rightangles to the normal
+			we cant make a crossvec from a vec thats the same as the vec
+			unlikely but possible, so make sure if the normal is (0,0,1)
+			that vec isnt the same or in the same direction even.*/
+			if (eve->no[0]<0.5)			vec[0]=1;
+			else if (eve->no[1]<0.5)	vec[1]=1;
+			else						vec[2]=1;
+			Crossf(plane, eve->no, vec);
+		}
+	} else if (ese->type==EDITEDGE) {
+		EditEdge *eed= ese->data;
+
+		/*the plane is simple, it runs allong the edge
+		however selecting different edges can swap the direction of the y axis.
+		this makes it less likely for the y axis of the manipulator
+		(running along the edge).. to flip less often.
+		at least its more pradictable */
+		if (eed->v2->co[1] > eed->v1->co[1]) /*check which to do first */
+			VecSubf(plane, eed->v2->co, eed->v1->co);
+		else
+			VecSubf(plane, eed->v1->co, eed->v2->co);
+		
+	} else if (ese->type==EDITFACE) {
+		EditFace *efa= ese->data;
+		float vec[3];
+		if (efa->v4) { /*if its a quad- set the plane along the 2 longest edges.*/
+			float vecA[3], vecB[3];
+			VecSubf(vecA, efa->v4->co, efa->v3->co);
+			VecSubf(vecB, efa->v1->co, efa->v2->co);
+			VecAddf(plane, vecA, vecB);
+			
+			VecSubf(vecA, efa->v1->co, efa->v4->co);
+			VecSubf(vecB, efa->v2->co, efa->v3->co);
+			VecAddf(vec, vecA, vecB);						
+			/*use the biggest edge length*/
+			if (plane[0]*plane[0]+plane[1]*plane[1]+plane[2]*plane[2] < vec[0]*vec[0]+vec[1]*vec[1]+vec[2]*vec[2])
+				VecCopyf(plane, vec);
+		} else {
+			/*start with v1-2 */
+			VecSubf(plane, efa->v1->co, efa->v2->co);
+			
+			/*test the edge between v2-3, use if longer */
+			VecSubf(vec, efa->v2->co, efa->v3->co);
+			if (plane[0]*plane[0]+plane[1]*plane[1]+plane[2]*plane[2] < vec[0]*vec[0]+vec[1]*vec[1]+vec[2]*vec[2])
+				VecCopyf(plane, vec);
+			
+			/*test the edge between v1-3, use if longer */
+			VecSubf(vec, efa->v3->co, efa->v1->co);
+			if (plane[0]*plane[0]+plane[1]*plane[1]+plane[2]*plane[2] < vec[0]*vec[0]+vec[1]*vec[1]+vec[2]*vec[2])
+				VecCopyf(plane, vec);
+		}
+	}
+}
+
+
+
 void EM_select_face(EditFace *efa, int sel)
 {
 	if(sel) {