Occlusion Query based selection.

This patch creates an interface for selection mechanisms in opengl. This
makes it possible to switch between occlusion query based or select
rendermode based selection transparently.

This is really useful on graphics drivers that do not accelerate the
select rendermode path (some ATI cards are notorious for this, and the
new path is used by default there), since occlusion queries are always
hardware accelerated due to their use in games.

The option can be found under system - selection. Auto just enables
occlusion queries for ATI users while the rest of the options enforce
one of the two methods always.

There is just one known change, previous code enforced nearest bone to
always get selected, even when mouse selecting near the same position, I
couldn't replicate the behaviour though.

patch by me with edits and review by Campbell.

Thanks!

4 files changed, 162 insertions, 133 deletions

diff --git a/source/blender/editors/space_view3d/drawarmature.c b/source/blender/editors/space_view3d/drawarmature.c
index 34634fc1807..4a6215df7f3 100644
--- a/source/blender/editors/space_view3d/drawarmature.c
+++ b/source/blender/editors/space_view3d/drawarmature.c
@@ -67,6 +67,7 @@
 
 #include "view3d_intern.h"
 
+#include "GPU_select.h"
 
 /* *************** Armature Drawing - Coloring API ***************************** */
 
@@ -551,7 +552,7 @@ static void draw_bone_points(const short dt, int armflag, unsigned int boneflag,
 	/*	Draw root point if we are not connected */
 	if ((boneflag & BONE_CONNECTED) == 0) {
 		if (id != -1)
-			glLoadName(id | BONESEL_ROOT);
+			GPU_select_load_id(id | BONESEL_ROOT);
 		
 		if (dt <= OB_WIRE) {
 			if (armflag & ARM_EDITMODE) {
@@ -574,7 +575,7 @@ static void draw_bone_points(const short dt, int armflag, unsigned int boneflag,
 	
 	/*	Draw tip point */
 	if (id != -1)
-		glLoadName(id | BONESEL_TIP);
+		GPU_select_load_id(id | BONESEL_TIP);
 	
 	if (dt <= OB_WIRE) {
 		if (armflag & ARM_EDITMODE) {
@@ -787,7 +788,7 @@ static void draw_sphere_bone_wire(float smat[4][4], float imat[4][4],
 	/*	Draw root point if we are not connected */
 	if ((boneflag & BONE_CONNECTED) == 0) {
 		if (id != -1)
-			glLoadName(id | BONESEL_ROOT);
+			GPU_select_load_id(id | BONESEL_ROOT);
 		
 		drawcircball(GL_LINE_LOOP, headvec, head, imat);
 	}
@@ -799,7 +800,7 @@ static void draw_sphere_bone_wire(float smat[4][4], float imat[4][4],
 	}
 	
 	if (id != -1)
-		glLoadName(id | BONESEL_TIP);
+		GPU_select_load_id(id | BONESEL_TIP);
 	
 	drawcircball(GL_LINE_LOOP, tailvec, tail, imat);
 	
@@ -830,7 +831,7 @@ static void draw_sphere_bone_wire(float smat[4][4], float imat[4][4],
 		cross_v3_v3v3(norvect, vec, imat[2]);
 		
 		if (id != -1)
-			glLoadName(id | BONESEL_BONE);
+			GPU_select_load_id(id | BONESEL_BONE);
 		
 		glBegin(GL_LINES);
 
@@ -907,7 +908,7 @@ static void draw_sphere_bone(const short dt, int armflag, int boneflag, short co
 	/*	Draw root point if we are not connected */
 	if ((boneflag & BONE_CONNECTED) == 0) {
 		if (id != -1)
-			glLoadName(id | BONESEL_ROOT);
+			GPU_select_load_id(id | BONESEL_ROOT);
 		gluSphere(qobj, head, 16, 10);
 	}
 	
@@ -918,7 +919,7 @@ static void draw_sphere_bone(const short dt, int armflag, int boneflag, short co
 	}
 
 	if (id != -1)
-		glLoadName(id | BONESEL_TIP);
+		GPU_select_load_id(id | BONESEL_TIP);
 	
 	glTranslatef(0.0f, 0.0f, length);
 	gluSphere(qobj, tail, 16, 10);
@@ -939,7 +940,7 @@ static void draw_sphere_bone(const short dt, int armflag, int boneflag, short co
 	
 	if (length > (head + tail)) {
 		if (id != -1)
-			glLoadName(id | BONESEL_BONE);
+			GPU_select_load_id(id | BONESEL_BONE);
 		
 		glEnable(GL_POLYGON_OFFSET_FILL);
 		glPolygonOffset(-1.0f, -1.0f);
@@ -1009,7 +1010,7 @@ static void draw_line_bone(int armflag, int boneflag, short constflag, unsigned
 		/*	Draw root point if we are not connected */
 		if ((boneflag & BONE_CONNECTED) == 0) {
 			if (G.f & G_PICKSEL) {  /* no bitmap in selection mode, crashes 3d cards... */
-				glLoadName(id | BONESEL_ROOT);
+				GPU_select_load_id(id | BONESEL_ROOT);
 				glBegin(GL_POINTS);
 				glVertex3f(0.0f, 0.0f, 0.0f);
 				glEnd();
@@ -1021,7 +1022,7 @@ static void draw_line_bone(int armflag, int boneflag, short constflag, unsigned
 		}
 		
 		if (id != -1)
-			glLoadName((GLuint) id | BONESEL_BONE);
+			GPU_select_load_id((GLuint) id | BONESEL_BONE);
 		
 		glBegin(GL_LINES);
 		glVertex3f(0.0f, 0.0f, 0.0f);
@@ -1031,7 +1032,7 @@ static void draw_line_bone(int armflag, int boneflag, short constflag, unsigned
 		/* tip */
 		if (G.f & G_PICKSEL) {
 			/* no bitmap in selection mode, crashes 3d cards... */
-			glLoadName(id | BONESEL_TIP);
+			GPU_select_load_id(id | BONESEL_TIP);
 			glBegin(GL_POINTS);
 			glVertex3f(0.0f, 1.0f, 0.0f);
 			glEnd();
@@ -1043,7 +1044,7 @@ static void draw_line_bone(int armflag, int boneflag, short constflag, unsigned
 		
 		/* further we send no names */
 		if (id != -1)
-			glLoadName(id & 0xFFFF);  /* object tag, for bordersel optim */
+			GPU_select_load_id(id & 0xFFFF);  /* object tag, for bordersel optim */
 		
 		if (armflag & ARM_POSEMODE)
 			set_pchan_glColor(PCHAN_COLOR_LINEBONE, boneflag, constflag);
@@ -1161,7 +1162,7 @@ static void draw_b_bone(const short dt, int armflag, int boneflag, short constfl
 	}
 	
 	if (id != -1) {
-		glLoadName((GLuint) id | BONESEL_BONE);
+		GPU_select_load_id((GLuint) id | BONESEL_BONE);
 	}
 	
 	/* set up solid drawing */
@@ -1266,13 +1267,13 @@ static void draw_wire_bone(const short dt, int armflag, int boneflag, short cons
 	/* this chunk not in object mode */
 	if (armflag & (ARM_EDITMODE | ARM_POSEMODE)) {
 		if (id != -1)
-			glLoadName((GLuint) id | BONESEL_BONE);
+			GPU_select_load_id((GLuint) id | BONESEL_BONE);
 		
 		draw_wire_bone_segments(pchan, bbones, length, segments);
 		
 		/* further we send no names */
 		if (id != -1)
-			glLoadName(id & 0xFFFF);    /* object tag, for bordersel optim */
+			GPU_select_load_id(id & 0xFFFF);    /* object tag, for bordersel optim */
 	}
 	
 	/* colors for modes */
@@ -1315,7 +1316,7 @@ static void draw_bone(const short dt, int armflag, int boneflag, short constflag
 	
 	/* now draw the bone itself */
 	if (id != -1) {
-		glLoadName((GLuint) id | BONESEL_BONE);
+		GPU_select_load_id((GLuint) id | BONESEL_BONE);
 	}
 	
 	/* wire? */
@@ -1370,7 +1371,7 @@ static void draw_custom_bone(Scene *scene, View3D *v3d, RegionView3D *rv3d, Obje
 	}
 	
 	if (id != -1) {
-		glLoadName((GLuint) id | BONESEL_BONE);
+		GPU_select_load_id((GLuint) id | BONESEL_BONE);
 	}
 	
 	draw_object_instance(scene, v3d, rv3d, ob, dt, armflag & ARM_POSEMODE);
@@ -1812,12 +1813,12 @@ static void draw_pose_bones(Scene *scene, View3D *v3d, ARegion *ar, Base *base,
 				index += 0x10000;  /* pose bones count in higher 2 bytes only */
 		}
 		
-		/* very very confusing... but in object mode, solid draw, we cannot do glLoadName yet,
+		/* very very confusing... but in object mode, solid draw, we cannot do GPU_select_load_id yet,
 		 * stick bones and/or wire custom-shapes are drawn in next loop 
 		 */
 		if (ELEM(arm->drawtype, ARM_LINE, ARM_WIRE) == 0 && (draw_wire == false) && index != -1) {
 			/* object tag, for bordersel optim */
-			glLoadName(index & 0xFFFF);
+			GPU_select_load_id(index & 0xFFFF);
 			index = -1;
 		}
 	}
@@ -1883,7 +1884,7 @@ static void draw_pose_bones(Scene *scene, View3D *v3d, ARegion *ar, Base *base,
 		/* stick or wire bones have not been drawn yet so don't clear object selection in this case */
 		if (ELEM(arm->drawtype, ARM_LINE, ARM_WIRE) == 0 && draw_wire && index != -1) {
 			/* object tag, for bordersel optim */
-			glLoadName(index & 0xFFFF);
+			GPU_select_load_id(index & 0xFFFF);
 			index = -1;
 		}
 	}
@@ -1926,7 +1927,7 @@ static void draw_pose_bones(Scene *scene, View3D *v3d, ARegion *ar, Base *base,
 						 */
 						if ((do_dashed & 2) && ((bone->flag & BONE_CONNECTED) == 0)) {
 							if (arm->flag & ARM_POSEMODE) {
-								glLoadName(index & 0xFFFF);  /* object tag, for bordersel optim */
+								GPU_select_load_id(index & 0xFFFF);  /* object tag, for bordersel optim */
 								UI_ThemeColor(TH_WIRE);
 							}
 							setlinestyle(3);
@@ -1946,7 +1947,7 @@ static void draw_pose_bones(Scene *scene, View3D *v3d, ARegion *ar, Base *base,
 									if (constflag & PCHAN_HAS_TARGET) glColor3ub(200, 120, 0);
 									else glColor3ub(200, 200, 50);  /* add theme! */
 
-									glLoadName(index & 0xFFFF);
+									GPU_select_load_id(index & 0xFFFF);
 									pchan_draw_IK_root_lines(pchan, !(do_dashed & 2));
 								}
 							}
@@ -1954,7 +1955,7 @@ static void draw_pose_bones(Scene *scene, View3D *v3d, ARegion *ar, Base *base,
 								if (bone->flag & BONE_SELECTED) {
 									glColor3ub(150, 200, 50);  /* add theme! */
 									
-									glLoadName(index & 0xFFFF);
+									GPU_select_load_id(index & 0xFFFF);
 									pchan_draw_IK_root_lines(pchan, !(do_dashed & 2));
 								}
 							}
@@ -2174,7 +2175,7 @@ static void draw_ebones(View3D *v3d, ARegion *ar, Object *ob, const short dt)
 	
 	/* if wire over solid, set offset */
 	index = -1;
-	glLoadName(-1);
+	GPU_select_load_id(-1);
 	if (ELEM(arm->drawtype, ARM_LINE, ARM_WIRE)) {
 		if (G.f & G_PICKSEL)
 			index = 0;
@@ -2223,7 +2224,7 @@ static void draw_ebones(View3D *v3d, ARegion *ar, Object *ob, const short dt)
 				/* offset to parent */
 				if (eBone->parent) {
 					UI_ThemeColor(TH_WIRE_EDIT);
-					glLoadName(-1);  /* -1 here is OK! */
+					GPU_select_load_id(-1);  /* -1 here is OK! */
 					setlinestyle(3);
 					
 					glBegin(GL_LINES);
@@ -2240,7 +2241,7 @@ static void draw_ebones(View3D *v3d, ARegion *ar, Object *ob, const short dt)
 	
 	/* restore */
 	if (index != -1) {
-		glLoadName(-1);
+		GPU_select_load_id(-1);
 	}
 
 	if (ELEM(arm->drawtype, ARM_LINE, ARM_WIRE)) {
diff --git a/source/blender/editors/space_view3d/drawobject.c b/source/blender/editors/space_view3d/drawobject.c
index 82fef4a85e8..8d39632e210 100644
--- a/source/blender/editors/space_view3d/drawobject.c
+++ b/source/blender/editors/space_view3d/drawobject.c
@@ -86,6 +86,7 @@
 
 #include "GPU_draw.h"
 #include "GPU_extensions.h"
+#include "GPU_select.h"
 
 #include "ED_mesh.h"
 #include "ED_particle.h"
@@ -1586,7 +1587,7 @@ static void draw_viewport_object_reconstruction(Scene *scene, Base *base, View3D
 			continue;
 
 		if (dflag & DRAW_PICKING)
-			glLoadName(base->selcol + (tracknr << 16));
+			GPU_select_load_id(base->selcol + (tracknr << 16));
 
 		glPushMatrix();
 		glTranslatef(track->bundle_pos[0], track->bundle_pos[1], track->bundle_pos[2]);
@@ -1737,7 +1738,7 @@ static void draw_viewport_reconstruction(Scene *scene, Base *base, View3D *v3d,
 	}
 
 	if (dflag & DRAW_PICKING)
-		glLoadName(base->selcol);
+		GPU_select_load_id(base->selcol);
 }
 
 /* flag similar to draw_object() */
@@ -6479,7 +6480,7 @@ static bool drawmball(Scene *scene, View3D *v3d, RegionView3D *rv3d, Base *base,
 			
 			if (G.f & G_PICKSEL) {
 				ml->selcol1 = code;
-				glLoadName(code++);
+				GPU_select_load_id(code++);
 			}
 		}
 		drawcircball(GL_LINE_LOOP, &(ml->x), ml->rad, imat);
@@ -6493,7 +6494,7 @@ static bool drawmball(Scene *scene, View3D *v3d, RegionView3D *rv3d, Base *base,
 			
 			if (G.f & G_PICKSEL) {
 				ml->selcol2 = code;
-				glLoadName(code++);
+				GPU_select_load_id(code++);
 			}
 			drawcircball(GL_LINE_LOOP, &(ml->x), ml->rad * atanf(ml->s) / (float)M_PI_2, imat);
 		}
diff --git a/source/blender/editors/space_view3d/view3d_select.c b/source/blender/editors/space_view3d/view3d_select.c
index f61f58c12db..46ea52054c5 100644
--- a/source/blender/editors/space_view3d/view3d_select.c
+++ b/source/blender/editors/space_view3d/view3d_select.c
@@ -1194,15 +1194,32 @@ static short selectbuffer_ret_hits_5(unsigned int *buffer, const short hits15, c
 
 /* we want a select buffer with bones, if there are... */
 /* so check three selection levels and compare */
-static short mixed_bones_object_selectbuffer(ViewContext *vc, unsigned int *buffer, const int mval[2])
+static short mixed_bones_object_selectbuffer(ViewContext *vc, unsigned int *buffer, const int mval[2], bool *p_do_nearest, bool enumerate)
 {
 	rcti rect;
 	int offs;
 	short hits15, hits9 = 0, hits5 = 0;
 	bool has_bones15 = false, has_bones9 = false, has_bones5 = false;
-	
+	static int last_mval[2] = {-100, -100};
+	bool do_nearest = false;
+	View3D *v3d = vc->v3d;
+
+	/* define if we use solid nearest select or not */
+	if (v3d->drawtype > OB_WIRE) {
+		do_nearest = true;
+		if (len_manhattan_v2v2_int(mval, last_mval) < 3) {
+			do_nearest = false;
+		}
+	}
+	copy_v2_v2_int(last_mval, mval);
+
+	if (p_do_nearest)
+		*p_do_nearest = do_nearest;
+
+	do_nearest = do_nearest && !enumerate;
+
 	BLI_rcti_init(&rect, mval[0] - 14, mval[0] + 14, mval[1] - 14, mval[1] + 14);
-	hits15 = view3d_opengl_select(vc, buffer, MAXPICKBUF, &rect);
+	hits15 = view3d_opengl_select(vc, buffer, MAXPICKBUF, &rect, do_nearest);
 	if (hits15 == 1) {
 		return selectbuffer_ret_hits_15(buffer, hits15);
 	}
@@ -1211,7 +1228,7 @@ static short mixed_bones_object_selectbuffer(ViewContext *vc, unsigned int *buff
 
 		offs = 4 * hits15;
 		BLI_rcti_init(&rect, mval[0] - 9, mval[0] + 9, mval[1] - 9, mval[1] + 9);
-		hits9 = view3d_opengl_select(vc, buffer + offs, MAXPICKBUF - offs, &rect);
+		hits9 = view3d_opengl_select(vc, buffer + offs, MAXPICKBUF - offs, &rect, do_nearest);
 		if (hits9 == 1) {
 			return selectbuffer_ret_hits_9(buffer, hits15, hits9);
 		}
@@ -1220,7 +1237,7 @@ static short mixed_bones_object_selectbuffer(ViewContext *vc, unsigned int *buff
 
 			offs += 4 * hits9;
 			BLI_rcti_init(&rect, mval[0] - 5, mval[0] + 5, mval[1] - 5, mval[1] + 5);
-			hits5 = view3d_opengl_select(vc, buffer + offs, MAXPICKBUF - offs, &rect);
+			hits5 = view3d_opengl_select(vc, buffer + offs, MAXPICKBUF - offs, &rect, do_nearest);
 			if (hits5 == 1) {
 				return selectbuffer_ret_hits_5(buffer, hits15, hits9, hits5);
 			}
@@ -1242,25 +1259,13 @@ static short mixed_bones_object_selectbuffer(ViewContext *vc, unsigned int *buff
 }
 
 /* returns basact */
-static Base *mouse_select_eval_buffer(ViewContext *vc, unsigned int *buffer, int hits, const int mval[2],
-                                      Base *startbase, bool has_bones)
+static Base *mouse_select_eval_buffer(ViewContext *vc, unsigned int *buffer, int hits,
+                                      Base *startbase, bool has_bones, bool do_nearest)
 {
 	Scene *scene = vc->scene;
 	View3D *v3d = vc->v3d;
 	Base *base, *basact = NULL;
-	static int lastmval[2] = {-100, -100};
 	int a;
-	bool do_nearest = false;
-	
-	/* define if we use solid nearest select or not */
-	if (v3d->drawtype > OB_WIRE) {
-		do_nearest = true;
-		if (ABS(mval[0] - lastmval[0]) < 3 && ABS(mval[1] - lastmval[1]) < 3) {
-			if (!has_bones) /* hrms, if theres bones we always do nearest */
-				do_nearest = false;
-		}
-	}
-	lastmval[0] = mval[0]; lastmval[1] = mval[1];
 	
 	if (do_nearest) {
 		unsigned int min = 0xFFFFFFFF;
@@ -1343,16 +1348,17 @@ Base *ED_view3d_give_base_under_cursor(bContext *C, const int mval[2])
 	Base *basact = NULL;
 	unsigned int buffer[4 * MAXPICKBUF];
 	int hits;
+	bool do_nearest;
 	
 	/* setup view context for argument to callbacks */
 	view3d_operator_needs_opengl(C);
 	view3d_set_viewcontext(C, &vc);
 	
-	hits = mixed_bones_object_selectbuffer(&vc, buffer, mval);
+	hits = mixed_bones_object_selectbuffer(&vc, buffer, mval, &do_nearest, false);
 	
 	if (hits > 0) {
 		const bool has_bones = selectbuffer_has_bones(buffer, hits);
-		basact = mouse_select_eval_buffer(&vc, buffer, hits, mval, vc.scene->base.first, has_bones);
+		basact = mouse_select_eval_buffer(&vc, buffer, hits, vc.scene->base.first, has_bones, do_nearest);
 	}
 	
 	return basact;
@@ -1439,10 +1445,11 @@ static bool mouse_select(bContext *C, const int mval[2],
 	}
 	else {
 		unsigned int buffer[4 * MAXPICKBUF];
+		bool do_nearest;
 
 		/* if objects have posemode set, the bones are in the same selection buffer */
 		
-		hits = mixed_bones_object_selectbuffer(&vc, buffer, mval);
+		hits = mixed_bones_object_selectbuffer(&vc, buffer, mval, &do_nearest, enumerate);
 		
 		if (hits > 0) {
 			/* note: bundles are handling in the same way as bones */
@@ -1453,7 +1460,7 @@ static bool mouse_select(bContext *C, const int mval[2],
 				basact = object_mouse_select_menu(C, &vc, buffer, hits, mval, toggle);
 			}
 			else {
-				basact = mouse_select_eval_buffer(&vc, buffer, hits, mval, startbase, has_bones);
+				basact = mouse_select_eval_buffer(&vc, buffer, hits, startbase, has_bones, do_nearest);
 			}
 			
 			if (has_bones && basact) {
@@ -1511,7 +1518,7 @@ static bool mouse_select(bContext *C, const int mval[2],
 						if (!changed) {
 							/* fallback to regular object selection if no new bundles were selected,
 							 * allows to select object parented to reconstruction object */
-							basact = mouse_select_eval_buffer(&vc, buffer, hits, mval, startbase, 0);
+							basact = mouse_select_eval_buffer(&vc, buffer, hits, startbase, 0, do_nearest);
 						}
 					}
 				}
@@ -1873,7 +1880,7 @@ static int do_meta_box_select(ViewContext *vc, rcti *rect, bool select, bool ext
 	unsigned int buffer[4 * MAXPICKBUF];
 	short hits;
 
-	hits = view3d_opengl_select(vc, buffer, MAXPICKBUF, rect);
+	hits = view3d_opengl_select(vc, buffer, MAXPICKBUF, rect, false);
 
 	if (extend == false && select)
 		BKE_mball_deselect_all(mb);
@@ -1907,7 +1914,7 @@ static int do_armature_box_select(ViewContext *vc, rcti *rect, bool select, bool
 	unsigned int buffer[4 * MAXPICKBUF];
 	short hits;
 
-	hits = view3d_opengl_select(vc, buffer, MAXPICKBUF, rect);
+	hits = view3d_opengl_select(vc, buffer, MAXPICKBUF, rect, false);
 	
 	/* clear flag we use to detect point was affected */
 	for (ebone = arm->edbo->first; ebone; ebone = ebone->next)
@@ -2001,7 +2008,7 @@ static int do_object_pose_box_select(bContext *C, ViewContext *vc, rcti *rect, b
 
 	/* selection buffer now has bones potentially too, so we add MAXPICKBUF */
 	vbuffer = MEM_mallocN(4 * (totobj + MAXPICKBUF) * sizeof(unsigned int), "selection buffer");
-	hits = view3d_opengl_select(vc, vbuffer, 4 * (totobj + MAXPICKBUF), rect);
+	hits = view3d_opengl_select(vc, vbuffer, 4 * (totobj + MAXPICKBUF), rect, false);
 	/*
 	 * LOGIC NOTES (theeth):
 	 * The buffer and ListBase have the same relative order, which makes the selection
diff --git a/source/blender/editors/space_view3d/view3d_view.c b/source/blender/editors/space_view3d/view3d_view.c
index 716f4b10fae..e51cf371a64 100644
--- a/source/blender/editors/space_view3d/view3d_view.c
+++ b/source/blender/editors/space_view3d/view3d_view.c
@@ -56,6 +56,7 @@
 #include "BIF_glutil.h"
 
 #include "GPU_draw.h"
+#include "GPU_select.h"
 
 #include "WM_api.h"
 #include "WM_types.h"
@@ -955,6 +956,78 @@ void view3d_viewmatrix_set(Scene *scene, View3D *v3d, RegionView3D *rv3d)
 	}
 }
 
+static void view3d_select_loop(ViewContext *vc, Scene *scene, View3D *v3d, ARegion *ar, bool use_obedit_skip)
+{
+	short code = 1;
+	char dt;
+	short dtx;
+
+	if (vc->obedit && vc->obedit->type == OB_MBALL) {
+		draw_object(scene, ar, v3d, BASACT, DRAW_PICKING | DRAW_CONSTCOLOR);
+	}
+	else if ((vc->obedit && vc->obedit->type == OB_ARMATURE)) {
+		/* if not drawing sketch, draw bones */
+		if (!BDR_drawSketchNames(vc)) {
+			draw_object(scene, ar, v3d, BASACT, DRAW_PICKING | DRAW_CONSTCOLOR);
+		}
+	}
+	else {
+		Base *base;
+
+		v3d->xray = true;  /* otherwise it postpones drawing */
+		for (base = scene->base.first; base; base = base->next) {
+			if (base->lay & v3d->lay) {
+
+				if ((base->object->restrictflag & OB_RESTRICT_SELECT) ||
+				    (use_obedit_skip && (scene->obedit->data == base->object->data)))
+				{
+					base->selcol = 0;
+				}
+				else {
+					base->selcol = code;
+
+					if (GPU_select_load_id(code)) {
+						draw_object(scene, ar, v3d, base, DRAW_PICKING | DRAW_CONSTCOLOR);
+
+						/* we draw duplicators for selection too */
+						if ((base->object->transflag & OB_DUPLI)) {
+							ListBase *lb;
+							DupliObject *dob;
+							Base tbase;
+
+							tbase.flag = OB_FROMDUPLI;
+							lb = object_duplilist(G.main->eval_ctx, scene, base->object);
+
+							for (dob = lb->first; dob; dob = dob->next) {
+								float omat[4][4];
+
+								tbase.object = dob->ob;
+								copy_m4_m4(omat, dob->ob->obmat);
+								copy_m4_m4(dob->ob->obmat, dob->mat);
+
+								/* extra service: draw the duplicator in drawtype of parent */
+								/* MIN2 for the drawtype to allow bounding box objects in groups for lods */
+								dt = tbase.object->dt;   tbase.object->dt = MIN2(tbase.object->dt, base->object->dt);
+								dtx = tbase.object->dtx; tbase.object->dtx = base->object->dtx;
+
+								draw_object(scene, ar, v3d, &tbase, DRAW_PICKING | DRAW_CONSTCOLOR);
+
+								tbase.object->dt = dt;
+								tbase.object->dtx = dtx;
+
+								copy_m4_m4(dob->ob->obmat, omat);
+							}
+							free_object_duplilist(lb);
+						}
+					}
+					code++;
+				}
+			}
+		}
+		v3d->xray = false;  /* restore */
+	}
+}
+
 /**
  * \warning be sure to account for a negative return value
  * This is an error, "Too many objects in select buffer"
@@ -962,17 +1035,16 @@ void view3d_viewmatrix_set(Scene *scene, View3D *v3d, RegionView3D *rv3d)
  *
  * \note (vc->obedit == NULL) can be set to explicitly skip edit-object selection.
  */
-short view3d_opengl_select(ViewContext *vc, unsigned int *buffer, unsigned int bufsize, const rcti *input)
+short view3d_opengl_select(ViewContext *vc, unsigned int *buffer, unsigned int bufsize, const rcti *input, bool do_nearest)
 {
 	Scene *scene = vc->scene;
 	View3D *v3d = vc->v3d;
 	ARegion *ar = vc->ar;
-	rctf rect;
-	short code, hits;
-	char dt;
-	short dtx;
+	rctf rect, selrect;
+	short hits;
 	const bool use_obedit_skip = (scene->obedit != NULL) && (vc->obedit == NULL);
-	
+	const bool do_passes = do_nearest && GPU_select_query_check_active();
+
 	G.f |= G_PICKSEL;
 	
 	/* case not a border select */
@@ -985,6 +1057,8 @@ short view3d_opengl_select(ViewContext *vc, unsigned int *buffer, unsigned int b
 	else {
 		BLI_rctf_rcti_copy(&rect, input);
 	}
+
+	selrect = rect;
 	
 	view3d_winmatrix_set(ar, v3d, &rect);
 	mul_m4_m4m4(vc->rv3d->persmat, vc->rv3d->winmat, vc->rv3d->viewmat);
@@ -997,78 +1071,24 @@ short view3d_opengl_select(ViewContext *vc, unsigned int *buffer, unsigned int b
 	if (vc->rv3d->rflag & RV3D_CLIPPING)
 		ED_view3d_clipping_set(vc->rv3d);
 	
-	glSelectBuffer(bufsize, (GLuint *)buffer);
-	glRenderMode(GL_SELECT);
-	glInitNames();  /* these two calls whatfor? It doesnt work otherwise */
-	glPushName(-1);
-	code = 1;
+	if (do_passes)
+		GPU_select_begin(buffer, bufsize, &selrect, GPU_SELECT_NEAREST_FIRST_PASS, 0);
+	else
+		GPU_select_begin(buffer, bufsize, &selrect, GPU_SELECT_ALL, 0);
+
+	view3d_select_loop(vc, scene, v3d, ar, use_obedit_skip);
+
+	hits = GPU_select_end();
 	
-	if (vc->obedit && vc->obedit->type == OB_MBALL) {
-		draw_object(scene, ar, v3d, BASACT, DRAW_PICKING | DRAW_CONSTCOLOR);
-	}
-	else if ((vc->obedit && vc->obedit->type == OB_ARMATURE)) {
-		/* if not drawing sketch, draw bones */
-		if (!BDR_drawSketchNames(vc)) {
-			draw_object(scene, ar, v3d, BASACT, DRAW_PICKING | DRAW_CONSTCOLOR);
-		}
-	}
-	else {
-		Base *base;
-		
-		v3d->xray = true;  /* otherwise it postpones drawing */
-		for (base = scene->base.first; base; base = base->next) {
-			if (base->lay & v3d->lay) {
-				
-				if ((base->object->restrictflag & OB_RESTRICT_SELECT) ||
-				    (use_obedit_skip && (scene->obedit->data == base->object->data)))
-				{
-					base->selcol = 0;
-				}
-				else {
-					base->selcol = code;
-					glLoadName(code);
-					draw_object(scene, ar, v3d, base, DRAW_PICKING | DRAW_CONSTCOLOR);
-					
-					/* we draw duplicators for selection too */
-					if ((base->object->transflag & OB_DUPLI)) {
-						ListBase *lb;
-						DupliObject *dob;
-						Base tbase;
-						
-						tbase.flag = OB_FROMDUPLI;
-						lb = object_duplilist(G.main->eval_ctx, scene, base->object);
-						
-						for (dob = lb->first; dob; dob = dob->next) {
-							float omat[4][4];
-							
-							tbase.object = dob->ob;
-							copy_m4_m4(omat, dob->ob->obmat);
-							copy_m4_m4(dob->ob->obmat, dob->mat);
-							
-							/* extra service: draw the duplicator in drawtype of parent */
-							/* MIN2 for the drawtype to allow bounding box objects in groups for lods */
-							dt = tbase.object->dt;   tbase.object->dt = MIN2(tbase.object->dt, base->object->dt);
-							dtx = tbase.object->dtx; tbase.object->dtx = base->object->dtx;
-
-							draw_object(scene, ar, v3d, &tbase, DRAW_PICKING | DRAW_CONSTCOLOR);
-							
-							tbase.object->dt = dt;
-							tbase.object->dtx = dtx;
-
-							copy_m4_m4(dob->ob->obmat, omat);
-						}
-						free_object_duplilist(lb);
-					}
-					code++;
-				}
-			}
-		}
-		v3d->xray = false;  /* restore */
+	/* second pass, to get the closest object to camera */
+	if (do_passes) {
+		GPU_select_begin(buffer, bufsize, &selrect, GPU_SELECT_NEAREST_SECOND_PASS, hits);
+
+		view3d_select_loop(vc, scene, v3d, ar, use_obedit_skip);
+
+		GPU_select_end();
 	}
-	
-	glPopName();    /* see above (pushname) */
-	hits = glRenderMode(GL_RENDER);
-	
+
 	G.f &= ~G_PICKSEL;
 	view3d_winmatrix_set(ar, v3d, NULL);
 	mul_m4_m4m4(vc->rv3d->persmat, vc->rv3d->winmat, vc->rv3d->viewmat);