Index: source/blender/editors/sculpt_paint/paint_intern.h
===================================================================
--- source/blender/editors/sculpt_paint/paint_intern.h	(revision 52534)
+++ source/blender/editors/sculpt_paint/paint_intern.h	(working copy)
@@ -61,8 +61,6 @@
                                      StrokeUpdateStep update_step, StrokeDone done, int event_type);
 void paint_stroke_data_free(struct wmOperator *op);
 
-int paint_space_stroke_enabled(struct Brush *br);
-
 struct wmKeyMap *paint_stroke_modal_keymap(struct wmKeyConfig *keyconf);
 int paint_stroke_modal(struct bContext *C, struct wmOperator *op, struct wmEvent *event);
 int paint_stroke_exec(struct bContext *C, struct wmOperator *op);
Index: source/blender/editors/sculpt_paint/paint_stroke.c
===================================================================
--- source/blender/editors/sculpt_paint/paint_stroke.c	(revision 52534)
+++ source/blender/editors/sculpt_paint/paint_stroke.c	(working copy)
@@ -67,6 +67,9 @@
 } PaintSample;
 
 typedef struct PaintStroke {
+	int one_time_init;
+	int smooth_init;
+
 	void *mode_data;
 	void *smooth_stroke_cursor;
 	wmTimer *timer;
@@ -97,25 +100,72 @@
 	StrokeDone done;
 } PaintStroke;
 
+
+/* Stroke Predicates
+ *****************************************************************************/
+
+static int is_airbrush(const PaintStroke *stroke)
+{
+	return stroke->brush->flag & BRUSH_AIRBRUSH;
+}
+
+static int is_grab_tool(const PaintStroke *stroke)
+{
+	return
+	        ELEM4(stroke->brush->sculpt_tool,
+	              SCULPT_TOOL_GRAB,
+	              SCULPT_TOOL_THUMB,
+	              SCULPT_TOOL_ROTATE,
+	              SCULPT_TOOL_SNAKE_HOOK);
+}
+
+static int is_anchor(const PaintStroke *stroke)
+{
+	return stroke->brush->flag & BRUSH_ANCHORED;
+}
+
+static int is_drag(const PaintStroke *stroke)
+{
+	return stroke->brush->flag & BRUSH_RESTORE_MESH;
+}
+
+static int is_smooth_stroke(const PaintStroke *stroke)
+{
+	return
+	        (stroke->brush->flag & BRUSH_SMOOTH_STROKE) &&
+	        !is_grab_tool(stroke) &&
+	        !is_anchor(stroke) &&
+	        !is_drag(stroke);
+}
+
+static int is_space(const PaintStroke *stroke)
+{
+	return
+	        (stroke->brush->flag & BRUSH_SPACE) &&
+	        !is_grab_tool(stroke) &&
+	        !is_anchor(stroke) &&
+	        !is_drag(stroke);
+}
+
+
 /*** Cursor ***/
-static void paint_draw_smooth_stroke(bContext *C, int x, int y, void *customdata) 
+static void paint_draw_smooth_stroke(bContext *C, int x, int y, void *customdata)
 {
-	Paint *paint = paint_get_active_from_context(C);
-	Brush *brush = paint_brush(paint);
+	Brush *brush = paint_brush(paint_get_active(CTX_data_scene(C)));
 	PaintStroke *stroke = customdata;
+	if (stroke && brush && is_smooth_stroke(stroke)) {
+		ARegion *ar = CTX_wm_region(C);
+		glColor4ubv(paint_get_active(CTX_data_scene(C))->paint_cursor_col);
+		glEnable(GL_LINE_SMOOTH);
+		glEnable(GL_BLEND);
 
-	glColor4ubv(paint->paint_cursor_col);
-	glEnable(GL_LINE_SMOOTH);
-	glEnable(GL_BLEND);
+		sdrawline(x, y,
+		          (int)stroke->last_mouse_position[0] - ar->winrct.xmin,
+		          (int)stroke->last_mouse_position[1] - ar->winrct.ymin);
 
-	if (stroke && brush && (brush->flag & BRUSH_SMOOTH_STROKE)) {
-		ARegion *ar = CTX_wm_region(C);
-		sdrawline(x, y, (int)stroke->last_mouse_position[0] - ar->winrct.xmin,
-		          (int)stroke->last_mouse_position[1] - ar->winrct.ymin);
+		glDisable(GL_BLEND);
+		glDisable(GL_LINE_SMOOTH);
 	}
-
-	glDisable(GL_BLEND);
-	glDisable(GL_LINE_SMOOTH);
 }
 
 /* if this is a tablet event, return tablet pressure and set *pen_flip
@@ -188,41 +238,54 @@
 	RNA_boolean_set(&itemptr, "pen_flip", pen_flip);
 	RNA_float_set(&itemptr, "pressure", pressure);
 
+	stroke->update_step(C, stroke, &itemptr);
+
 	copy_v2_v2(stroke->last_mouse_position, mouse_out);
+}
 
-	stroke->update_step(C, stroke, &itemptr);
+static void smooth(float a[2], float b[2], float v, float u)
+{
+	a[0]= v * a[0] + u * b[0];
+	a[1]= v * a[1] + u * b[1];
 }
 
 /* Returns zero if no sculpt changes should be made, non-zero otherwise */
-static int paint_smooth_stroke(PaintStroke *stroke, float output[2],
-                               const PaintSample *sample)
+static int smooth_stroke(PaintStroke *stroke, float output[2],
+                         const PaintSample *sample)
 {
 	output[0] = sample->mouse[0];
 	output[1] = sample->mouse[1];
 
-	if ((stroke->brush->flag & BRUSH_SMOOTH_STROKE) &&  
-	    !ELEM4(stroke->brush->sculpt_tool,
-	           SCULPT_TOOL_GRAB,
-	           SCULPT_TOOL_THUMB,
-	           SCULPT_TOOL_ROTATE,
-	           SCULPT_TOOL_SNAKE_HOOK) &&
-	    !(stroke->brush->flag & BRUSH_ANCHORED) &&
-	    !(stroke->brush->flag & BRUSH_RESTORE_MESH))
-	{
-		float u = stroke->brush->smooth_stroke_factor, v = 1.0f - u;
-		float dx = stroke->last_mouse_position[0] - sample->mouse[0];
-		float dy = stroke->last_mouse_position[1] - sample->mouse[1];
-
-		/* If the mouse is moving within the radius of the last move,
-		 * don't update the mouse position. This allows sharp turns. */
-		if (dx * dx + dy * dy < stroke->brush->smooth_stroke_radius * stroke->brush->smooth_stroke_radius)
+	if (is_smooth_stroke(stroke)) {
+		if (!(stroke->smooth_init)) {
+			copy_v2_v2(stroke->last_mouse_position, output);
 			return 0;
+		}
+		else {
+			float u = stroke->brush->smooth_stroke_factor;
+			float v = 1.0f - u;
+			float dx = stroke->last_mouse_position[0] - sample->mouse[0];
+			float dy = stroke->last_mouse_position[1] - sample->mouse[1];
 
-		output[0] = sample->mouse[0] * v + stroke->last_mouse_position[0] * u;
-		output[1] = sample->mouse[1] * v + stroke->last_mouse_position[1] * u;
+			float dist_sq = dx*dx + dy*dy;
+			float radius_sq = stroke->brush->smooth_stroke_radius * stroke->brush->smooth_stroke_radius;
+
+			/* If the mouse is moving within the radius of the last move,
+			 * don't update the mouse position. This allows sharp turns. */
+
+			if (dist_sq < radius_sq) {
+				return 0;
+			}
+			else {
+				smooth(output, stroke->last_mouse_position, v, u);
+
+				return 1;
+			}
+		}
 	}
-
-	return 1;
+	else {
+		return 1;
+	}
 }
 
 /* For brushes with stroke spacing enabled, moves mouse in steps
@@ -232,40 +295,46 @@
 	PaintStroke *stroke = op->customdata;
 	int cnt = 0;
 
-	if (paint_space_stroke_enabled(stroke->brush)) {
-		float mouse[2];
-		float vec[2];
-		float length, scale;
+	float mouse[2];
+	float vec[2];
+	float length, scale;
 
-		copy_v2_v2(mouse, stroke->last_mouse_position);
-		sub_v2_v2v2(vec, final_mouse, mouse);
+	copy_v2_v2(mouse, stroke->last_mouse_position);
+	sub_v2_v2v2(vec, final_mouse, mouse);
 
-		length = len_v2(vec);
+	length = len_v2(vec);
 
-		if (length > FLT_EPSILON) {
-			const Scene *scene = CTX_data_scene(C);
-			int steps;
-			int i;
-			float pressure = 1.0f;
+	if (length > FLT_EPSILON) {
+		const Scene *scene = CTX_data_scene(C);
+		int steps;
+		int i;
+		float pressure;
 
-			/* XXX mysterious :) what has 'use size' do with this here... if you don't check for it, pressure fails */
-			if (BKE_brush_use_size_pressure(scene, stroke->brush))
-				pressure = event_tablet_data(event, NULL);
-			
-			if (pressure > FLT_EPSILON) {
-				/* brushes can have a minimum size of 1.0 but with pressure it can be smaller then a pixel
-				 * causing very high step sizes, hanging blender [#32381] */
-				const float size_clamp = max_ff(1.0f, BKE_brush_size_get(scene, stroke->brush) * pressure);
-				scale = (size_clamp * stroke->brush->spacing / 50.0f) / length;
-				if (scale > FLT_EPSILON) {
-					mul_v2_fl(vec, scale);
+		if (BKE_brush_use_size_pressure(scene, stroke->brush)) {
+			pressure = event_tablet_data(event, NULL);
+		}
+		else {
+			pressure = 1;
+		}
 
-					steps = (int)(1.0f / scale);
+		if (pressure > FLT_EPSILON) {
+			/* brushes can have a minimum size of 1.0 but with pressure it
+			 * can be smaller then a pixel causing very high number of steps and
+			 * hanging blender [#32381] */
+			const float size_clamp = max_ff(
+			      1.0f,
+			      BKE_brush_size_get(scene, stroke->brush) * pressure);
 
-					for (i = 0; i < steps; ++i, ++cnt) {
-						add_v2_v2(mouse, vec);
-						paint_brush_stroke_add_step(C, op, event, mouse);
-					}
+			scale = (size_clamp * stroke->brush->spacing / 50.0f) / length;
+
+			if (scale > FLT_EPSILON) {
+				mul_v2_fl(vec, scale);
+
+				steps = (int)(1.0f / scale);
+
+				for (i = 0; i < steps; ++i, ++cnt) {
+					add_v2_v2(mouse, vec);
+					paint_brush_stroke_add_step(C, op, event, mouse);
 				}
 			}
 		}
@@ -303,6 +372,35 @@
 	op->customdata = NULL;
 }
 
+static void one_time_init(
+        const struct bContext *C,
+        struct PointerRNA *UNUSED(ptr),
+        struct PaintStroke *stroke,
+        struct wmEvent *UNUSED(evt))
+{
+	if (!(stroke->one_time_init)) {
+		if (is_smooth_stroke(stroke)) {
+			stroke->smooth_stroke_cursor =
+			        WM_paint_cursor_activate(
+			            CTX_wm_manager(C),
+			            paint_poll,
+			            paint_draw_smooth_stroke,
+			            stroke);
+		}
+
+		if (is_airbrush(stroke)) {
+			stroke->timer =
+			        WM_event_add_timer(
+			            CTX_wm_manager(C),
+			            CTX_wm_window(C),
+			            TIMER,
+			            stroke->brush->rate);
+		}
+
+		stroke->one_time_init= 1;
+	}
+}
+
 static void stroke_done(struct bContext *C, struct wmOperator *op)
 {
 	struct PaintStroke *stroke = op->customdata;
@@ -323,14 +421,6 @@
 	paint_stroke_data_free(op);
 }
 
-/* Returns zero if the stroke dots should not be spaced, non-zero otherwise */
-int paint_space_stroke_enabled(Brush *br)
-{
-	return (br->flag & BRUSH_SPACE) &&
-	       !(br->flag & BRUSH_ANCHORED) &&
-	       !ELEM4(br->sculpt_tool, SCULPT_TOOL_GRAB, SCULPT_TOOL_THUMB, SCULPT_TOOL_ROTATE, SCULPT_TOOL_SNAKE_HOOK);
-}
-
 #define PAINT_STROKE_MODAL_CANCEL 1
 
 /* called in paint_ops.c, on each regeneration of keymaps  */
@@ -401,7 +491,10 @@
 	PaintStroke *stroke = op->customdata;
 	PaintSample sample_average;
 	float mouse[2];
-	int first = 0;
+	int airbrush; /* using either a timer or mouse events but not both */
+	int event_ok; /* is event type matched to the airbrush mode */
+	int input_ok; /* the conditions required by the input mode have been met */
+	int first_event; /* true only during first event */
 
 	paint_stroke_add_sample(p, stroke, event->x, event->y);
 	paint_stroke_sample_average(stroke, &sample_average);
@@ -410,25 +503,42 @@
 	 * this isn't perfect... even when an extra MOUSEMOVE is spoofed, the stroke discards it
 	 * since the 2D deltas are zero -- code in this file needs to be updated to use the
 	 * post-NDOF_MOTION MOUSEMOVE */
-	if (event->type == NDOF_MOTION)
+	if (event->type == NDOF_MOTION) {
 		return OPERATOR_PASS_THROUGH;
+	}
 
-	if (!stroke->stroke_started) {
-		copy_v2_v2(stroke->last_mouse_position, sample_average.mouse);
-		stroke->stroke_started = stroke->test_start(C, op, sample_average.mouse);
 
-		if (stroke->stroke_started) {
-			stroke->smooth_stroke_cursor =
-			    WM_paint_cursor_activate(CTX_wm_manager(C), paint_poll, paint_draw_smooth_stroke, stroke);
+	/* Initialize */
+	one_time_init(C, op->ptr, stroke, event);
+	airbrush = is_airbrush(stroke);
 
-			if (stroke->brush->flag & BRUSH_AIRBRUSH)
-				stroke->timer = WM_event_add_timer(CTX_wm_manager(C), CTX_wm_window(C), TIMER, stroke->brush->rate);
-		}
+	first_event = (event->type == stroke->event_type && event->val == KM_PRESS);
 
-		first = 1;
-		//ED_region_tag_redraw(ar);
+	if (first_event) {
+		event_ok = 1;
 	}
+	else if (airbrush) {
+		event_ok = (event->type == TIMER && event->customdata == stroke->timer);
+	}
+	else {
+		event_ok = ELEM(event->type, MOUSEMOVE, INBETWEEN_MOUSEMOVE);
+	}
 
+	if (event_ok) {
+		input_ok = smooth_stroke(stroke, mouse, &sample_average);
+	}
+	else {
+		/* input cannot be ok if the event was not. */
+		input_ok = 0;
+	}
+
+	if (input_ok && !stroke->stroke_started) {
+		copy_v2_v2(stroke->last_mouse_position, mouse);
+
+		stroke->stroke_started = stroke->test_start(C, op, mouse);
+	}
+
+
 	/* Cancel */
 	if (event->type == EVT_MODAL_MAP && event->val == PAINT_STROKE_MODAL_CANCEL) {
 		if (op->type->cancel)
@@ -437,42 +547,26 @@
 			return paint_stroke_cancel(C, op);
 	}
 
+
+	/* Finish */
 	if (event->type == stroke->event_type && event->val == KM_RELEASE) {
 		stroke_done(C, op);
 		return OPERATOR_FINISHED;
 	}
-	else if ((first) ||
-	         (ELEM(event->type, MOUSEMOVE, INBETWEEN_MOUSEMOVE)) ||
-	         (event->type == TIMER && (event->customdata == stroke->timer)) )
-	{
-		if (stroke->stroke_started) {
-			if (paint_smooth_stroke(stroke, mouse, &sample_average)) {
-				if (paint_space_stroke_enabled(stroke->brush)) {
-					if (!paint_space_stroke(C, op, event, mouse)) {
-						//ED_region_tag_redraw(ar);
-					}
-				}
-				else {
-					paint_brush_stroke_add_step(C, op, event, mouse);
-				}
-			}
-			else {
-				; //ED_region_tag_redraw(ar);
-			}
+
+
+	/* Steps */
+	if (input_ok && stroke->stroke_started) {
+		if (!first_event && is_space(stroke)) {
+			paint_space_stroke(C, op, event, mouse);
 		}
+		else {
+			paint_brush_stroke_add_step(C, op, event, mouse);
+		}
 	}
 
-	/* we want the stroke to have the first daub at the start location
-	 * instead of waiting till we have moved the space distance */
-	if (first &&
-	    stroke->stroke_started &&
-	    paint_space_stroke_enabled(stroke->brush) &&
-	    !(stroke->brush->flag & BRUSH_ANCHORED) &&
-	    !(stroke->brush->flag & BRUSH_SMOOTH_STROKE))
-	{
-		paint_brush_stroke_add_step(C, op, event, mouse);
-	}
-	
+	WM_tag_redraw_overlay(CTX_wm_window(C), stroke->vc.ar);
+
 	return OPERATOR_RUNNING_MODAL;
 }
 
Index: source/blender/editors/sculpt_paint/sculpt.c
===================================================================
--- source/blender/editors/sculpt_paint/sculpt.c	(revision 52534)
+++ source/blender/editors/sculpt_paint/sculpt.c	(working copy)
@@ -3558,8 +3558,18 @@
 	 *      brush coord/pressure/etc.
 	 *      It's more an events design issue, which doesn't split coordinate/pressure/angle
 	 *      changing events. We should avoid this after events system re-design */
-	if (paint_space_stroke_enabled(brush) || cache->first_time)
+
+	/* I'm going to re-evaluate this situation soon -- jwilkins */
+	if (cache->first_time ||
+	    ((brush->flag & BRUSH_SPACE) &&
+	     !ELEM4(brush->sculpt_tool,
+	            SCULPT_TOOL_GRAB,
+	            SCULPT_TOOL_THUMB,
+	            SCULPT_TOOL_ROTATE,
+	            SCULPT_TOOL_SNAKE_HOOK)))
+	{
 		cache->pressure = RNA_float_get(ptr, "pressure");
+	}
 
 	/* Truly temporary data that isn't stored in properties */
 
Index: source/blender/windowmanager/intern/wm_draw.c
===================================================================
--- source/blender/windowmanager/intern/wm_draw.c	(revision 52534)
+++ source/blender/windowmanager/intern/wm_draw.c	(working copy)
@@ -734,7 +790,7 @@
 		return win->drawmethod;
 }
 
-void wm_tag_redraw_overlay(wmWindow *win, ARegion *ar)
+void WM_tag_redraw_overlay(wmWindow *win, ARegion *ar)
 {
 	/* for draw triple gestures, paint cursors don't need region redraw */
 	if (ar && win) {
Index: source/blender/windowmanager/intern/wm_gesture.c
===================================================================
--- source/blender/windowmanager/intern/wm_gesture.c	(revision 52534)
+++ source/blender/windowmanager/intern/wm_gesture.c	(working copy)
@@ -359,5 +359,5 @@
 	if (screen)
 		screen->do_draw_gesture = TRUE;
 
-	wm_tag_redraw_overlay(win, ar);
+	WM_tag_redraw_overlay(win, ar);
 }
Index: source/blender/windowmanager/WM_api.h
===================================================================
--- source/blender/windowmanager/WM_api.h	(revision 52534)
+++ source/blender/windowmanager/WM_api.h	(working copy)
@@ -375,8 +375,11 @@
 			/* Draw (for screenshot) */
 void		WM_redraw_windows(struct bContext *C);
 
-void        WM_main_playanim(int argc, const char **argv);
+void		WM_main_playanim(int argc, const char **argv);
 
+			/* ask for just the overlay to be redrawn */
+void		WM_tag_redraw_overlay(struct wmWindow *win, struct ARegion *ar);
+
 /* debugging only, convenience function to write on crash */
 int write_crash_blend(void);
 
@@ -385,4 +388,3 @@
 #endif
 
 #endif /* __WM_API_H__ */
-
Index: source/blender/windowmanager/wm_draw.h
===================================================================
--- source/blender/windowmanager/wm_draw.h	(revision 52534)
+++ source/blender/windowmanager/wm_draw.h	(working copy)
@@ -41,7 +41,5 @@
 void		wm_draw_window_clear	(struct wmWindow *win);
 void		wm_draw_region_clear	(struct wmWindow *win, struct ARegion *ar);
 
-void		wm_tag_redraw_overlay	(struct wmWindow *win, struct ARegion *ar);
-
 #endif /* __WM_DRAW_H__ */