=== Transform Snap ===

Draw a circle around the snapping point for visual aid.

Different snapping target method, switchable in the 3d view header menu in the Transform menu.

* Closest: Snaps the closest vertex to the point
* Median: Snaps the median of the selection to the point
* Center: Snaps the transform center to the point (this is different from median because you can use Cursor/Boundbox as center)

Fix a bug with constraints/snap handling.

8 files changed, 201 insertions, 57 deletions

diff --git a/source/blender/include/BIF_transform.h b/source/blender/include/BIF_transform.h
index ecc4ec248ad..e67789e9b23 100755
--- a/source/blender/include/BIF_transform.h
+++ b/source/blender/include/BIF_transform.h
@@ -76,6 +76,7 @@ void BIF_setLocalAxisConstraint(char axis, char *text);
 void BIF_setLocalLockConstraint(char axis, char *text);
 void BIF_drawConstraint(void);
 void BIF_drawPropCircle(void);
+void BIF_drawSnap(void);
 void BIF_getPropCenter(float *center);
 
 void BIF_TransformSetUndo(char *str);
diff --git a/source/blender/include/transform.h b/source/blender/include/transform.h
index 7f12f765bbf..0a6a19a674d 100755
--- a/source/blender/include/transform.h
+++ b/source/blender/include/transform.h
@@ -251,6 +251,13 @@ typedef struct TransInfo {
 #define TD_VERSE_VERT		64
 #endif
 
+/* transsnap->status */
+#define SNAP_ON			0x1
+#define TARGET_INIT		0x2
+#define POINT_INIT		0x4
+
+
+
 void checkFirstTime(void);
 
 void setTransformViewMatrices(TransInfo *t);
diff --git a/source/blender/makesdna/DNA_view3d_types.h b/source/blender/makesdna/DNA_view3d_types.h
index c174c975252..27ccc318067 100644
--- a/source/blender/makesdna/DNA_view3d_types.h
+++ b/source/blender/makesdna/DNA_view3d_types.h
@@ -167,6 +167,11 @@ typedef struct View3D {
 #define V3D_OPP_DIRECTION_NAME	1
 #define V3D_FLYMODE				2
 #define V3D_TRANSFORM_SNAP		4
+#define V3D_SNAP_TARGET			(8|16)
+#define V3D_SNAP_TARGET_CLOSEST	0
+#define V3D_SNAP_TARGET_CENTER	8
+#define V3D_SNAP_TARGET_MEDIAN	16
+
 
 /* View3D->around */
 #define V3D_CENTRE		 0
diff --git a/source/blender/src/drawview.c b/source/blender/src/drawview.c
index 2ff4399dadd..d22408f02e3 100644
--- a/source/blender/src/drawview.c
+++ b/source/blender/src/drawview.c
@@ -2900,6 +2900,7 @@ void drawview3dspace(ScrArea *sa, void *spacedata)
 	if(G.moving) {
 		BIF_drawConstraint();
 		if(G.obedit) BIF_drawPropCircle();	// only editmode has proportional edit
+		BIF_drawSnap();
 	}
 
 	if(G.scene->radio) RAD_drawall(v3d->drawtype>=OB_SOLID);
diff --git a/source/blender/src/header_view3d.c b/source/blender/src/header_view3d.c
index e91929fa5f9..759a0085598 100644
--- a/source/blender/src/header_view3d.c
+++ b/source/blender/src/header_view3d.c
@@ -1696,6 +1696,21 @@ static void do_view3d_transformmenu(void *arg, int event)
 		initTransform(TFM_CURVE_SHRINKFATTEN, CTX_NONE);
 		Transform();
 		break;
+	case 15:
+		G.vd->flag2 ^= V3D_TRANSFORM_SNAP;
+		break;
+	case 16:
+		G.vd->flag2 &= ~V3D_SNAP_TARGET;
+		G.vd->flag2 |= V3D_SNAP_TARGET_CLOSEST;
+		break;
+	case 17:
+		G.vd->flag2 &= ~V3D_SNAP_TARGET;
+		G.vd->flag2 |= V3D_SNAP_TARGET_CENTER;
+		break;
+	case 18:
+		G.vd->flag2 &= ~V3D_SNAP_TARGET;
+		G.vd->flag2 |= V3D_SNAP_TARGET_MEDIAN;
+		break;
 	}
 	allqueue(REDRAWVIEW3D, 0);
 }
@@ -1747,6 +1762,35 @@ static uiBlock *view3d_transformmenu(void *arg_unused)
 		uiDefIconTextBut(block, BUTM, 1, ICON_BLANK1, "Center Cursor",          0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 12, "");
 	}
 	
+	if (G.obedit != NULL && G.obedit->type==OB_MESH)
+	{
+		uiDefBut(block, SEPR, 0, "",                    0, yco-=6, menuwidth, 6, NULL, 0.0, 0.0, 0, 0, "");
+	
+		if (G.vd->flag2 & V3D_TRANSFORM_SNAP)
+			uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_HLT, "Snap",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 15, "");
+		else
+			uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Snap",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 15, "");
+			
+		switch(G.vd->flag2 & V3D_SNAP_TARGET)
+		{
+			case V3D_SNAP_TARGET_CLOSEST:
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_HLT, "Snap Closest",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 16, "");
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Snap Center",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 17, "");
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Snap Median",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 18, "");
+				break;
+			case V3D_SNAP_TARGET_CENTER:
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Snap Closest",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 16, "");
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_HLT, "Snap Center",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 17, "");
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Snap Median",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 18, "");
+				break;
+			case V3D_SNAP_TARGET_MEDIAN:
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Snap Closest",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 16, "");
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Snap Center",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 17, "");
+				uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_HLT, "Snap Median",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 18, "");
+				break;
+		}
+	}
+
 	uiBlockSetDirection(block, UI_RIGHT);
 	uiTextBoundsBlock(block, 60);
 	return block;
@@ -2262,9 +2306,6 @@ static void do_view3d_edit_objectmenu(void *arg, int event)
 		if(session) b_verse_push_object(session, ob);
 		break;
 #endif
-	case 17: /* Transform snap to grid */
-		G.vd->flag2 ^= V3D_TRANSFORM_SNAP;
-		break;
 	}
 	allqueue(REDRAWVIEW3D, 0);
 }
@@ -2289,11 +2330,6 @@ static uiBlock *view3d_edit_objectmenu(void *arg_unused)
 		}
 	}
 #endif
-
-	if (G.vd->flag2 & V3D_TRANSFORM_SNAP)
-		uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_HLT, "Transform Snap",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 17, "");
-	else
-		uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Transform Snap",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 17, "");
 	
 
 	uiDefIconTextBut(block, BUTM, 1, ICON_MENU_PANEL, "Transform Properties|N",		0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 0, 15, "");
@@ -2831,9 +2867,6 @@ static void do_view3d_edit_meshmenu(void *arg, int event)
 		if(session) b_verse_push_object(session, G.obedit);
 		break;
 #endif
-	case 17: /* Transform snap to grid */
-		G.vd->flag2 ^= V3D_TRANSFORM_SNAP;
-		break;
 	}
 	allqueue(REDRAWVIEW3D, 0);
 }
@@ -2861,11 +2894,6 @@ static uiBlock *view3d_edit_meshmenu(void *arg_unused)
 	
 	uiDefBut(block, SEPR, 0, "",				0, yco-=6, menuwidth, 6, NULL, 0.0, 0.0, 0, 0, "");
 	
-	if (G.vd->flag2 & V3D_TRANSFORM_SNAP)
-		uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_HLT, "Transform Snap",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 17, "");
-	else
-		uiDefIconTextBut(block, BUTM, 1, ICON_CHECKBOX_DEHLT, "Transform Snap",			0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 17, "");
-
 	uiDefIconTextBut(block, BUTM, 1, ICON_MENU_PANEL, "Transform Properties...|N",		0, yco-=20, menuwidth, 19, NULL, 0.0, 0.0, 1, 2, "");
 	uiDefIconTextBlockBut(block, view3d_transformmenu, NULL, ICON_RIGHTARROW_THIN, "Transform", 0, yco-=20, 120, 19, "");
 	uiDefIconTextBlockBut(block, view3d_edit_mirrormenu, NULL, ICON_RIGHTARROW_THIN, "Mirror", 0, yco-=20, 120, 19, "");
diff --git a/source/blender/src/transform.c b/source/blender/src/transform.c
index 59564ec83dd..7e406e9c61c 100755
--- a/source/blender/src/transform.c
+++ b/source/blender/src/transform.c
@@ -98,6 +98,14 @@
 TransInfo Trans = {TFM_INIT, 0};	// enforce init on first usage
 
 /******************************** Helper functions ************************************/
+
+/* GLOBAL Wrapper Fonctions */
+
+void BIF_drawSnap()
+{
+	drawSnapping(&Trans);
+}
+
 /* ************************** Dashed help line **************************** */
 
 
@@ -2158,9 +2166,9 @@ int Translation(TransInfo *t, short mval[2])
 
 	if (t->con.mode & CON_APPLY) {
 		float pvec[3] = {0.0f, 0.0f, 0.0f};
+		applySnapping(t, t->vec);
 		t->con.applyVec(t, NULL, t->vec, tvec, pvec);
 		VECCOPY(t->vec, tvec);
-		applySnapping(t, t->vec);
 		headerTranslation(t, pvec, str);
 	}
 	else {
diff --git a/source/blender/src/transform_constraints.c b/source/blender/src/transform_constraints.c
index be7a0bd2636..f67b3acff3a 100755
--- a/source/blender/src/transform_constraints.c
+++ b/source/blender/src/transform_constraints.c
@@ -241,24 +241,29 @@ static void applyAxisConstraintVec(TransInfo *t, TransData *td, float in[3], flo
 	VECCOPY(out, in);
 	if (!td && t->con.mode & CON_APPLY) {
 		Mat3MulVecfl(t->con.pmtx, out);
-		if (getConstraintSpaceDimension(t) == 2) {
-			if (out[0] != 0.0f || out[1] != 0.0f || out[2] != 0.0f) {
-				planeProjection(t, in, out);
-			}
-		}
-		else if (getConstraintSpaceDimension(t) == 1) {
-			float c[3];
-
-			if (t->con.mode & CON_AXIS0) {
-				VECCOPY(c, t->con.mtx[0]);
-			}
-			else if (t->con.mode & CON_AXIS1) {
-				VECCOPY(c, t->con.mtx[1]);
+		
+		// With snap, a projection is alright, no need to correct for view alignment
+		if ((t->tsnap.status & SNAP_ON) == 0)
+			{
+			if (getConstraintSpaceDimension(t) == 2) {
+				if (out[0] != 0.0f || out[1] != 0.0f || out[2] != 0.0f) {
+					planeProjection(t, in, out);
+				}
 			}
-			else if (t->con.mode & CON_AXIS2) {
-				VECCOPY(c, t->con.mtx[2]);
+			else if (getConstraintSpaceDimension(t) == 1) {
+				float c[3];
+	
+				if (t->con.mode & CON_AXIS0) {
+					VECCOPY(c, t->con.mtx[0]);
+				}
+				else if (t->con.mode & CON_AXIS1) {
+					VECCOPY(c, t->con.mtx[1]);
+				}
+				else if (t->con.mode & CON_AXIS2) {
+					VECCOPY(c, t->con.mtx[2]);
+				}
+				axisProjection(t, c, in, out);
 			}
-			axisProjection(t, c, in, out);
 		}
 		postConstraintChecks(t, out, pvec);
 	}
diff --git a/source/blender/src/transform_snap.c b/source/blender/src/transform_snap.c
index ba2c3b7c316..cdd4fb793ba 100644
--- a/source/blender/src/transform_snap.c
+++ b/source/blender/src/transform_snap.c
@@ -37,6 +37,7 @@
 #include "PIL_time.h"
 
 #include "DNA_object_types.h"
+#include "DNA_scene_types.h"
 #include "DNA_space_types.h"
 #include "DNA_userdef_types.h"
 #include "DNA_view3d_types.h"
@@ -58,10 +59,7 @@
 
 #include "transform.h"
 #include "mydevice.h"		/* for KEY defines	*/
-
-#define SNAP_ON			0x1
-#define TARGET_INIT		0x2
-#define POINT_INIT		0x4
+#include "blendef.h" /* for selection modes */
 
 /********************* PROTOTYPES ***********************/
 
@@ -81,8 +79,23 @@ void TargetSnapClosest(TransInfo *t);
 
 void drawSnapping(TransInfo *t)
 {
-	if (t->tsnap.status & SNAP_ON) {
-		// Do something nice
+	if ((t->tsnap.status & (SNAP_ON|POINT_INIT|TARGET_INIT)) == (SNAP_ON|POINT_INIT|TARGET_INIT)) {
+		float unitmat[4][4];
+		char col[4];
+		
+		BIF_GetThemeColor3ubv(TH_TRANSFORM, col);
+		glColor4ub(col[0], col[1], col[2], 128);
+		
+		glPushMatrix();
+		
+		glTranslatef(t->tsnap.snapPoint[0], t->tsnap.snapPoint[1], t->tsnap.snapPoint[2]);
+		
+		/* sets view screen aligned */
+		glRotatef( -360.0f*saacos(G.vd->viewquat[0])/(float)M_PI, G.vd->viewquat[1], G.vd->viewquat[2], G.vd->viewquat[3]);
+
+		Mat4One(unitmat);
+		drawcircball(GL_LINE_LOOP, unitmat[3], 0.1f, unitmat);
+		glPopMatrix();
 	}
 }
 
@@ -152,7 +165,6 @@ void setSnappingCallback(TransInfo *t)
 	case TFM_TRANSLATION:
 		t->tsnap.applySnap = ApplySnapTranslation;
 		t->tsnap.calcSnap = CalcSnapGeometry;
-		t->tsnap.targetSnap = TargetSnapClosest;
 		break;
 	case TFM_ROTATION:
 		t->tsnap.applySnap = NULL;
@@ -164,6 +176,20 @@ void setSnappingCallback(TransInfo *t)
 		t->tsnap.applySnap = NULL;
 		break;
 	}
+	
+	switch(G.vd->flag2 & V3D_SNAP_TARGET)
+	{
+		case V3D_SNAP_TARGET_CLOSEST:
+			t->tsnap.targetSnap = TargetSnapClosest;
+			break;
+		case V3D_SNAP_TARGET_CENTER:
+			t->tsnap.targetSnap = TargetSnapCenter;
+			break;
+		case V3D_SNAP_TARGET_MEDIAN:
+			t->tsnap.targetSnap = TargetSnapMedian;
+			break;
+	}
+
 }
 
 /********************** APPLY **************************/
@@ -171,11 +197,12 @@ void setSnappingCallback(TransInfo *t)
 void ApplySnapTranslation(TransInfo *t, float vec[3])
 {
 	VecSubf(vec, t->tsnap.snapPoint, t->tsnap.snapTarget);
-	
+/*	
 	if (t->con.mode & CON_APPLY)
 	{
 		Mat3MulVecfl(t->con.pmtx, vec);
 	}
+*/
 }
 
 void ApplySnapRotation(TransInfo *t, float vec[3])
@@ -194,24 +221,52 @@ void CalcSnapGeometry(TransInfo *t, float *vec)
 {
 	if (G.obedit != NULL && G.obedit->type==OB_MESH)
 	{
-		EditVert *nearest=NULL;
-		int dist = 50; // Use a user defined value here
-		
-		// use findnearestverts in vert mode, others in other modes
-		nearest = findnearestvert(&dist, 0);
-		
-		if (nearest != NULL)
+		/*if (G.scene->selectmode & B_SEL_VERT)*/
 		{
-			VECCOPY(t->tsnap.snapPoint, nearest->co);
+			EditVert *nearest=NULL;
+			int dist = 50; // Use a user defined value here
 			
-			Mat4MulVecfl(G.obedit->obmat, t->tsnap.snapPoint);
+			// use findnearestverts in vert mode, others in other modes
+			nearest = findnearestvert(&dist, 0);
 			
-			t->tsnap.status |=  POINT_INIT;
+			if (nearest != NULL)
+			{
+				VECCOPY(t->tsnap.snapPoint, nearest->co);
+				
+				Mat4MulVecfl(G.obedit->obmat, t->tsnap.snapPoint);
+				
+				t->tsnap.status |=  POINT_INIT;
+			}
+			else
+			{
+				t->tsnap.status &= ~POINT_INIT;
+			}
 		}
-		else
+		/*
+		if (G.scene->selectmode & B_SEL_EDGE)
 		{
-			t->tsnap.status &= ~POINT_INIT;
+			EditEdge *nearest=NULL;
+			int dist = 50; // Use a user defined value here
+			
+			// use findnearestverts in vert mode, others in other modes
+			nearest = findnearestedge(&dist);
+			
+			if (nearest != NULL)
+			{
+				VecAddf(t->tsnap.snapPoint, nearest->v1->co, nearest->v2->co);
+				
+				VecMulf(t->tsnap.snapPoint, 0.5f); 
+				
+				Mat4MulVecfl(G.obedit->obmat, t->tsnap.snapPoint);
+				
+				t->tsnap.status |=  POINT_INIT;
+			}
+			else
+			{
+				t->tsnap.status &= ~POINT_INIT;
+			}
 		}
+		*/
 	}
 }
 
@@ -219,15 +274,49 @@ void CalcSnapGeometry(TransInfo *t, float *vec)
 
 void TargetSnapCenter(TransInfo *t)
 {
-	VECCOPY(t->tsnap.snapTarget, t->center);	
-	if(t->flag & (T_EDIT|T_POSE)) {
-		Object *ob= G.obedit?G.obedit:t->poseobj;
-		Mat4MulVecfl(ob->obmat, t->tsnap.snapTarget);
+	// Only need to calculate once
+	if ((t->tsnap.status & TARGET_INIT) == 0)
+	{
+		VECCOPY(t->tsnap.snapTarget, t->center);	
+		if(t->flag & (T_EDIT|T_POSE)) {
+			Object *ob= G.obedit?G.obedit:t->poseobj;
+			Mat4MulVecfl(ob->obmat, t->tsnap.snapTarget);
+		}
+		
+		t->tsnap.status |= TARGET_INIT;		
+	}
+}
+
+void TargetSnapMedian(TransInfo *t)
+{
+	// Only need to calculate once
+	if ((t->tsnap.status & TARGET_INIT) == 0)
+	{
+		TransData *td = NULL;
+
+		t->tsnap.snapTarget[0] = 0;
+		t->tsnap.snapTarget[1] = 0;
+		t->tsnap.snapTarget[2] = 0;
+		
+		for (td = t->data; td != NULL && td->flag & TD_SELECTED ; td++)
+		{
+			VecAddf(t->tsnap.snapTarget, t->tsnap.snapTarget, td->iloc);
+		}
+		
+		VecMulf(t->tsnap.snapTarget, 1.0 / t->total);
+		
+		if(t->flag & (T_EDIT|T_POSE)) {
+			Object *ob= G.obedit?G.obedit:t->poseobj;
+			Mat4MulVecfl(ob->obmat, t->tsnap.snapTarget);
+		}
+		
+		t->tsnap.status |= TARGET_INIT;		
 	}
 }
 
 void TargetSnapClosest(TransInfo *t)
 {
+	// Only valid if a snap point has been selected
 	if (t->tsnap.status & POINT_INIT)
 	{
 		TransData *closest = NULL, *td = NULL;