Added to the Parameter Editor mode new stroke geometry modifier `Blueprint'

that produces a blueprint using circular, elliptic, and square contour strokes.
Related changes and bug fixes were made as follows:

* The randomness in radius and center has been transformed into optional
parameters of the pyBluePrintCirclesShader and pyBluePrintEllipsesShader.
Also a new optional parameter to control the randomness of backbone
stretching has been added to the pyBluePrintSquaresShader.

* A bug in the pyBluePrintSquaresShader that invisible stroke vertices at
corners of rectangular contour strokes were not properly drawn.  The problem
was due to the changes of the / operator between Python 2.x to 3.x.  Even
when the two operands of the division operator are integers, Python 3.x
gives a floating-point number when the quotient is not an integer.  The fix
was just to replace the / operator by the // operator for integer division.

* An unpleasant discontinuity in circular and elliptical contour strokes
was fixed.

* The length parameter of the Backbone Stretcher geometry modifier has been
renamed to `backbone_length' in line with the parameter of the same name in
the pyBluePrintSquaresShader.

8 files changed, 181 insertions, 52 deletions

diff --git a/release/scripts/freestyle/style_modules/parameter_editor.py b/release/scripts/freestyle/style_modules/parameter_editor.py
index 5036fa78438..5531082e68b 100644
--- a/release/scripts/freestyle/style_modules/parameter_editor.py
+++ b/release/scripts/freestyle/style_modules/parameter_editor.py
@@ -973,7 +973,7 @@ def process(layer_name, lineset_name):
                 m.frequency, m.amplitude, m.octaves, m.angle, _seed.get(m.seed)))
         elif m.type == "BACKBONE_STRETCHER":
             shaders_list.append(BackboneStretcherShader(
-                m.amount))
+                m.backbone_length))
         elif m.type == "TIP_REMOVER":
             shaders_list.append(TipRemoverShader(
                 m.tip_length))
@@ -983,6 +983,16 @@ def process(layer_name, lineset_name):
         elif m.type == "GUIDING_LINES":
             shaders_list.append(GuidingLinesShader(
                 m.offset))
+        elif m.type == "BLUEPRINT":
+            if m.shape == "CIRCLES":
+                shaders_list.append(pyBluePrintCirclesShader(
+                    m.rounds, m.random_radius, m.random_center))
+            elif m.shape == "ELLIPSES":
+                shaders_list.append(pyBluePrintEllipsesShader(
+                    m.rounds, m.random_radius, m.random_center))
+            elif m.shape == "SQUARES":
+                shaders_list.append(pyBluePrintSquaresShader(
+                    m.rounds, m.backbone_length, m.random_backbone))
     color = linestyle.color
     shaders_list.append(ConstantColorShader(color.r, color.g, color.b, linestyle.alpha))
     shaders_list.append(ConstantThicknessShader(linestyle.thickness))
diff --git a/release/scripts/freestyle/style_modules/shaders.py b/release/scripts/freestyle/style_modules/shaders.py
index b8271820ce6..70941477a7b 100755
--- a/release/scripts/freestyle/style_modules/shaders.py
+++ b/release/scripts/freestyle/style_modules/shaders.py
@@ -959,15 +959,19 @@ class pyPerlinNoise2DShader(StrokeShader):
 		stroke.UpdateLength()
 
 class pyBluePrintCirclesShader(StrokeShader):
-	def __init__(self, turns = 1):
+	def __init__(self, turns = 1, random_radius = 3, random_center = 5):
 		StrokeShader.__init__(self)
 		self.__turns = turns
+		self.__random_center = random_center
+		self.__random_radius = random_radius
 	def getName(self):
 		return "pyBluePrintCirclesShader"
 	def shade(self, stroke):
-		p_min = Vector([10000, 10000])
-		p_max = Vector([0, 0])
 		it = stroke.strokeVerticesBegin()
+		if it.isEnd():
+			return
+		p_min = it.getObject().getPoint()
+		p_max = it.getObject().getPoint()
 		while it.isEnd() == 0:
 			p = it.getObject().getPoint()
 			if (p.x < p_min.x):
@@ -986,23 +990,30 @@ class pyBluePrintCirclesShader(StrokeShader):
 #		print("max  :", p_max.x, p_max.y) # DEBUG
 #		print("----------------------") # DEBUG
 #######################################################	
-		sv_nb = sv_nb / self.__turns
+		sv_nb = sv_nb // self.__turns
 		center = (p_min + p_max) / 2
 		radius = (center.x - p_min.x + center.y - p_min.y) / 2
 		p_new = Vector([0, 0])
 #######################################################
+		R = self.__random_radius
+		C = self.__random_center
+		i = 0
 		it = stroke.strokeVerticesBegin()
 		for j in range(self.__turns):
-			radius = radius + randint(-3, 3)
-			center.x = center.x + randint(-5, 5)
-			center.y = center.y + randint(-5, 5)
-			i = 0
+			prev_radius = radius
+			prev_center = center
+			radius = radius + randint(-R, R)
+			center = center + Vector([randint(-C, C), randint(-C, C)])
 			while i < sv_nb and it.isEnd() == 0:
-				p_new.x = center.x + radius * cos(2 * pi * float(i) / float(sv_nb - 1))
-				p_new.y = center.y + radius * sin(2 * pi * float(i) / float(sv_nb - 1))
+				t = float(i) / float(sv_nb - 1)
+				r = prev_radius + (radius - prev_radius) * t
+				c = prev_center + (center - prev_center) * t
+				p_new.x = c.x + r * cos(2 * pi * t)
+				p_new.y = c.y + r * sin(2 * pi * t)
 				it.getObject().setPoint(p_new)
 				i = i + 1
 				it.increment()
+			i = 1
 		verticesToRemove = []
 		while it.isEnd() == 0:
 			verticesToRemove.append(it.getObject())
@@ -1012,15 +1023,19 @@ class pyBluePrintCirclesShader(StrokeShader):
 		stroke.UpdateLength()
 
 class pyBluePrintEllipsesShader(StrokeShader):
-	def __init__(self, turns = 1):
+	def __init__(self, turns = 1, random_radius = 3, random_center = 5):
 		StrokeShader.__init__(self)
 		self.__turns = turns
+		self.__random_center = random_center
+		self.__random_radius = random_radius
 	def getName(self):
 		return "pyBluePrintEllipsesShader"
 	def shade(self, stroke):
-		p_min = Vector([10000, 10000])
-		p_max = Vector([0, 0])
 		it = stroke.strokeVerticesBegin()
+		if it.isEnd():
+			return
+		p_min = it.getObject().getPoint()
+		p_max = it.getObject().getPoint()
 		while it.isEnd() == 0:
 			p = it.getObject().getPoint()
 			if (p.x < p_min.x):
@@ -1034,25 +1049,30 @@ class pyBluePrintEllipsesShader(StrokeShader):
 			it.increment()
 		stroke.Resample(32 * self.__turns)
 		sv_nb = stroke.strokeVerticesSize()
-		sv_nb = sv_nb / self.__turns
+		sv_nb = sv_nb // self.__turns
 		center = (p_min + p_max) / 2
-		radius_x = center.x - p_min.x
-		radius_y = center.y - p_min.y
+		radius = center - p_min
 		p_new = Vector([0, 0])
 #######################################################
+		R = self.__random_radius
+		C = self.__random_center
+		i = 0
 		it = stroke.strokeVerticesBegin()
 		for j in range(self.__turns):
-			radius_x = radius_x + randint(-3, 3)
-			radius_y = radius_y + randint(-3, 3)
-			center.x = center.x + randint(-5, 5)
-			center.y = center.y + randint(-5, 5)
-			i = 0
+			prev_radius = radius
+			prev_center = center
+			radius = radius + Vector([randint(-R, R), randint(-R, R)])
+			center = center + Vector([randint(-C, C), randint(-C, C)])
 			while i < sv_nb and it.isEnd() == 0:
-				p_new.x = center.x + radius_x * cos(2 * pi * float(i) / float(sv_nb - 1))
-				p_new.y = center.y + radius_y * sin(2 * pi * float(i) / float(sv_nb - 1))
+				t = float(i) / float(sv_nb - 1)
+				r = prev_radius + (radius - prev_radius) * t
+				c = prev_center + (center - prev_center) * t
+				p_new.x = c.x + r.x * cos(2 * pi * t)
+				p_new.y = c.y + r.y * sin(2 * pi * t)
 				it.getObject().setPoint(p_new)
 				i = i + 1
 				it.increment()
+			i = 1
 		verticesToRemove = []
 		while it.isEnd() == 0:
 			verticesToRemove.append(it.getObject())
@@ -1063,18 +1083,21 @@ class pyBluePrintEllipsesShader(StrokeShader):
 
 
 class pyBluePrintSquaresShader(StrokeShader):
-	def __init__(self, turns = 1, bb_len = 10):
+	def __init__(self, turns = 1, bb_len = 10, bb_rand = 0):
 		StrokeShader.__init__(self)
 		self.__turns = turns
 		self.__bb_len = bb_len
+		self.__bb_rand = bb_rand
 
 	def getName(self):
 		return "pyBluePrintSquaresShader"
 
 	def shade(self, stroke):
-		p_min = Vector([10000, 10000])
-		p_max = Vector([0, 0])
 		it = stroke.strokeVerticesBegin()
+		if it.isEnd():
+			return
+		p_min = it.getObject().getPoint()
+		p_max = it.getObject().getPoint()
 		while it.isEnd() == 0:
 			p = it.getObject().getPoint()
 			if (p.x < p_min.x):
@@ -1089,23 +1112,37 @@ class pyBluePrintSquaresShader(StrokeShader):
 		stroke.Resample(32 * self.__turns)
 		sv_nb = stroke.strokeVerticesSize()
 #######################################################	
-		sv_nb = sv_nb / self.__turns
-		first = sv_nb / 4
+		sv_nb = sv_nb // self.__turns
+		first = sv_nb // 4
 		second = 2 * first
 		third = 3 * first
 		fourth = sv_nb
-		vec_first = Vector([p_max.x - p_min.x + 2 * self.__bb_len, 0])
-		vec_second = Vector([0, p_max.y - p_min.y + 2 * self.__bb_len])
-		vec_third = vec_first * -1
-		vec_fourth = vec_second * -1
 		p_first = Vector([p_min.x - self.__bb_len, p_min.y])
+		p_first_end = Vector([p_max.x + self.__bb_len, p_min.y])
 		p_second = Vector([p_max.x, p_min.y - self.__bb_len])
+		p_second_end = Vector([p_max.x, p_max.y + self.__bb_len])
 		p_third = Vector([p_max.x + self.__bb_len, p_max.y])
+		p_third_end = Vector([p_min.x - self.__bb_len, p_max.y])
 		p_fourth = Vector([p_min.x, p_max.y + self.__bb_len])
+		p_fourth_end = Vector([p_min.x, p_min.y - self.__bb_len])
 #######################################################
+		R = self.__bb_rand
+		r = self.__bb_rand // 2
 		it = stroke.strokeVerticesBegin()
 		visible = 1
 		for j in range(self.__turns):
+			p_first = p_first + Vector([randint(-R, R), randint(-r, r)])
+			p_first_end = p_first_end + Vector([randint(-R, R), randint(-r, r)])
+			p_second = p_second + Vector([randint(-r, r), randint(-R, R)])
+			p_second_end = p_second_end + Vector([randint(-r, r), randint(-R, R)])
+			p_third = p_third + Vector([randint(-R, R), randint(-r, r)])
+			p_third_end = p_third_end + Vector([randint(-R, R), randint(-r, r)])
+			p_fourth = p_fourth + Vector([randint(-r, r), randint(-R, R)])
+			p_fourth_end = p_fourth_end + Vector([randint(-r, r), randint(-R, R)])
+			vec_first = p_first_end - p_first
+			vec_second = p_second_end - p_second
+			vec_third = p_third_end - p_third
+			vec_fourth = p_fourth_end - p_fourth
 			i = 0
 			while i < sv_nb and it.isEnd() == 0:
 				if i < first:
@@ -1156,20 +1193,10 @@ class pyBluePrintDirectedSquaresShader(StrokeShader):
 	def shade(self, stroke):
 		stroke.Resample(32 * self.__turns)
 		p_mean = Vector([0, 0])
-		p_min = Vector([10000, 10000])
-		p_max = Vector([0, 0])
 		it = stroke.strokeVerticesBegin()
 		while it.isEnd() == 0:
 			p = it.getObject().getPoint()
 			p_mean = p_mean + p
-## 			if (p.x < p_min.x):
-## 				p_min.x = p.x
-## 			if (p.x > p_max.x):
-## 				p_max.x = p.x
-## 			if (p.y < p_min.y):
-## 				p_min.y = p.y
-## 			if (p.y > p_max.y):
-## 				p_max.y = p.y
 			it.increment()
 		sv_nb = stroke.strokeVerticesSize()
 		p_mean = p_mean / sv_nb
@@ -1202,8 +1229,8 @@ class pyBluePrintDirectedSquaresShader(StrokeShader):
 			e1 = Vector([cos(theta), sin(theta)]) * sqrt(lambda1) * self.__mult
 			e2 = Vector([cos(theta + pi / 2), sin(theta + pi / 2)]) * sqrt(lambda2) * self.__mult
 #######################################################	
-		sv_nb = sv_nb / self.__turns
-		first = sv_nb / 4
+		sv_nb = sv_nb // self.__turns
+		first = sv_nb // 4
 		second = 2 * first
 		third = 3 * first
 		fourth = sv_nb
diff --git a/release/scripts/startup/bl_ui/properties_render.py b/release/scripts/startup/bl_ui/properties_render.py
index 71f207f6e5a..c6002a53023 100644
--- a/release/scripts/startup/bl_ui/properties_render.py
+++ b/release/scripts/startup/bl_ui/properties_render.py
@@ -550,6 +550,17 @@ class RENDER_PT_freestyle_linestyle(RenderButtonsPanel, Panel):
             elif modifier.type == "GUIDING_LINES":
                 box.prop(modifier, "offset")
 
+            elif modifier.type == "BLUEPRINT":
+                row = box.row()
+                row.prop(modifier, "shape", expand=True)
+                box.prop(modifier, "rounds")
+                if modifier.shape in ["CIRCLES", "ELLIPSES"]:
+                    box.prop(modifier, "random_radius")
+                    box.prop(modifier, "random_center")
+                elif modifier.shape == "SQUARES":
+                    box.prop(modifier, "backbone_length")
+                    box.prop(modifier, "random_backbone")
+
     def draw(self, context):
         layout = self.layout
 
diff --git a/source/blender/blenkernel/intern/linestyle.c b/source/blender/blenkernel/intern/linestyle.c
index a8d8038e7f9..0c48590410e 100644
--- a/source/blender/blenkernel/intern/linestyle.c
+++ b/source/blender/blenkernel/intern/linestyle.c
@@ -63,7 +63,8 @@ static char *modifier_name[LS_MODIFIER_NUM] = {
 	"Tip Remover",
 	"Calligraphy",
 	"Polygonalization",
-	"Guiding Lines"};
+	"Guiding Lines",
+	"Blueprint"};
 
 static void default_linestyle_settings(FreestyleLineStyle *linestyle)
 {
@@ -398,6 +399,9 @@ int FRS_add_linestyle_geometry_modifier(FreestyleLineStyle *linestyle, int type)
 	case LS_MODIFIER_GUIDING_LINES:
 		size = sizeof(LineStyleGeometryModifier_GuidingLines);
 		break;
+	case LS_MODIFIER_BLUEPRINT:
+		size = sizeof(LineStyleGeometryModifier_Blueprint);
+		break;
 	default:
 		return -1; /* unknown modifier type */
 	}
@@ -435,7 +439,7 @@ int FRS_add_linestyle_geometry_modifier(FreestyleLineStyle *linestyle, int type)
 		((LineStyleGeometryModifier_PerlinNoise2D *)m)->angle = 45.0;
 		break;
 	case LS_MODIFIER_BACKBONE_STRETCHER:
-		((LineStyleGeometryModifier_BackboneStretcher *)m)->amount = 10.0;
+		((LineStyleGeometryModifier_BackboneStretcher *)m)->backbone_length = 10.0;
 		break;
 	case LS_MODIFIER_TIP_REMOVER:
 		((LineStyleGeometryModifier_TipRemover *)m)->tip_length = 10.0;
@@ -446,6 +450,14 @@ int FRS_add_linestyle_geometry_modifier(FreestyleLineStyle *linestyle, int type)
 	case LS_MODIFIER_GUIDING_LINES:
 		((LineStyleGeometryModifier_GuidingLines *)m)->offset = 0.0;
 		break;
+	case LS_MODIFIER_BLUEPRINT:
+		((LineStyleGeometryModifier_Blueprint *)m)->flags = LS_MODIFIER_BLUEPRINT_CIRCLES;
+		((LineStyleGeometryModifier_Blueprint *)m)->rounds = 1;
+		((LineStyleGeometryModifier_Blueprint *)m)->backbone_length = 10.f;
+		((LineStyleGeometryModifier_Blueprint *)m)->random_radius = 3;
+		((LineStyleGeometryModifier_Blueprint *)m)->random_center = 5;
+		((LineStyleGeometryModifier_Blueprint *)m)->random_backbone = 5;
+		break;
 	}
 	add_to_modifier_list(&linestyle->geometry_modifiers, m);
 	return 0;
@@ -474,6 +486,8 @@ void FRS_remove_linestyle_geometry_modifier(FreestyleLineStyle *linestyle, LineS
 		break;
 	case LS_MODIFIER_GUIDING_LINES:
 		break;
+	case LS_MODIFIER_BLUEPRINT:
+		break;
 	}
 	BLI_freelinkN(&linestyle->geometry_modifiers, m);
 }
diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index b37364e830b..3accc871548 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -2723,6 +2723,9 @@ static void write_linestyle_geometry_modifiers(WriteData *wd, ListBase *modifier
 		case LS_MODIFIER_GUIDING_LINES:
 			struct_name = "LineStyleGeometryModifier_GuidingLines";
 			break;
+		case LS_MODIFIER_BLUEPRINT:
+			struct_name = "LineStyleGeometryModifier_Blueprint";
+			break;
 		default:
 			struct_name = "LineStyleGeometryModifier"; // this should not happen
 		}
diff --git a/source/blender/makesdna/DNA_linestyle_types.h b/source/blender/makesdna/DNA_linestyle_types.h
index a34a4285e55..a73dd707caa 100644
--- a/source/blender/makesdna/DNA_linestyle_types.h
+++ b/source/blender/makesdna/DNA_linestyle_types.h
@@ -64,7 +64,8 @@ typedef struct LineStyleModifier {
 #define LS_MODIFIER_CALLIGRAPHY            13
 #define LS_MODIFIER_POLYGONIZATION         14
 #define LS_MODIFIER_GUIDING_LINES          15
-#define LS_MODIFIER_NUM                    16
+#define LS_MODIFIER_BLUEPRINT              16
+#define LS_MODIFIER_NUM                    17
 
 /* LineStyleModifier::flags */
 #define LS_MODIFIER_ENABLED     1
@@ -284,7 +285,7 @@ typedef struct LineStyleGeometryModifier_PerlinNoise2D {
 typedef struct LineStyleGeometryModifier_BackboneStretcher {
 	struct LineStyleModifier modifier;
 
-	float amount;
+	float backbone_length;
 	int pad;
 
 } LineStyleGeometryModifier_BackboneStretcher;
@@ -313,6 +314,23 @@ typedef struct LineStyleGeometryModifier_GuidingLines {
 
 } LineStyleGeometryModifier_GuidingLines;
 
+/* LineStyleGeometryModifier_BluePrintLines::shape */
+#define LS_MODIFIER_BLUEPRINT_CIRCLES   1
+#define LS_MODIFIER_BLUEPRINT_ELLIPSES  2
+#define LS_MODIFIER_BLUEPRINT_SQUARES   4
+
+typedef struct LineStyleGeometryModifier_Blueprint {
+	struct LineStyleModifier modifier;
+
+	int flags;
+	unsigned int rounds;
+	float backbone_length;
+	unsigned int random_radius;
+	unsigned int random_center;
+	unsigned int random_backbone;
+
+} LineStyleGeometryModifier_Blueprint;
+
 /* Calligraphic thickness modifier */
 
 typedef struct LineStyleThicknessModifier_Calligraphy {
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index 67d4b2deee1..1e0231fd4a6 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -299,6 +299,7 @@ extern StructRNA RNA_LineStyleColorModifier_Material;
 extern StructRNA RNA_LineStyleGeometryModifier;
 extern StructRNA RNA_LineStyleGeometryModifier_BackboneStretcher;
 extern StructRNA RNA_LineStyleGeometryModifier_BezierCurve;
+extern StructRNA RNA_LineStyleGeometryModifier_Blueprint;
 extern StructRNA RNA_LineStyleGeometryModifier_GuidingLines;
 extern StructRNA RNA_LineStyleGeometryModifier_PerlinNoise1D;
 extern StructRNA RNA_LineStyleGeometryModifier_PerlinNoise2D;
diff --git a/source/blender/makesrna/intern/rna_linestyle.c b/source/blender/makesrna/intern/rna_linestyle.c
index 6ae8bd2253e..58be8fc62c4 100644
--- a/source/blender/makesrna/intern/rna_linestyle.c
+++ b/source/blender/makesrna/intern/rna_linestyle.c
@@ -61,6 +61,7 @@ EnumPropertyItem linestyle_thickness_modifier_type_items[] ={
 EnumPropertyItem linestyle_geometry_modifier_type_items[] ={
 	{LS_MODIFIER_BACKBONE_STRETCHER, "BACKBONE_STRETCHER", ICON_MODIFIER, "Backbone Stretcher", ""},
 	{LS_MODIFIER_BEZIER_CURVE, "BEZIER_CURVE", ICON_MODIFIER, "Bezier Curve", ""},
+	{LS_MODIFIER_BLUEPRINT, "BLUEPRINT", ICON_MODIFIER, "Blueprint", ""},
 	{LS_MODIFIER_GUIDING_LINES, "GUIDING_LINES", ICON_MODIFIER, "Guiding Lines", ""},
 	{LS_MODIFIER_PERLIN_NOISE_1D, "PERLIN_NOISE_1D", ICON_MODIFIER, "Perlin Noise 1D", ""},
 	{LS_MODIFIER_PERLIN_NOISE_2D, "PERLIN_NOISE_2D", ICON_MODIFIER, "Perlin Noise 2D", ""},
@@ -154,6 +155,8 @@ static StructRNA *rna_LineStyle_geometry_modifier_refine(struct PointerRNA *ptr)
 			return &RNA_LineStyleGeometryModifier_Polygonalization;
 		case LS_MODIFIER_GUIDING_LINES:
 			return &RNA_LineStyleGeometryModifier_GuidingLines;
+		case LS_MODIFIER_BLUEPRINT:
+			return &RNA_LineStyleGeometryModifier_Blueprint;
 		default:
 			return &RNA_LineStyleGeometryModifier;
 	}
@@ -378,6 +381,12 @@ static void rna_def_linestyle_modifiers(BlenderRNA *brna)
 	StructRNA *srna;
 	PropertyRNA *prop;
 
+	static EnumPropertyItem blueprint_shape_items[] = {
+		{LS_MODIFIER_BLUEPRINT_CIRCLES, "CIRCLES", 0, "Circles", "Draw a blueprint using circular contour strokes"},
+		{LS_MODIFIER_BLUEPRINT_ELLIPSES, "ELLIPSES", 0, "Ellipses", "Draw a blueprint using elliptic contour strokes"},
+		{LS_MODIFIER_BLUEPRINT_SQUARES, "SQUARES", 0, "Squares", "Draw a blueprint using square contour strokes"},
+		{0, NULL, 0, NULL, NULL}};
+
 	srna= RNA_def_struct(brna, "LineStyleModifier", NULL);
 	RNA_def_struct_ui_text(srna, "Line Style Modifier", "Base type to define modifiers");
 
@@ -651,9 +660,9 @@ static void rna_def_linestyle_modifiers(BlenderRNA *brna)
 	RNA_def_struct_ui_text(srna, "Backbone Stretcher", "Stretch the beginning and the end of stroke backbone");
 	rna_def_geometry_modifier(srna);
 
-	prop= RNA_def_property(srna, "amount", PROP_FLOAT, PROP_NONE);
-	RNA_def_property_float_sdna(prop, NULL, "amount");
-	RNA_def_property_ui_text(prop, "Amount", "Amount of stretching");
+	prop= RNA_def_property(srna, "backbone_length", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_float_sdna(prop, NULL, "backbone_length");
+	RNA_def_property_ui_text(prop, "Backbone Length", "Amount of backbone stretching");
 	RNA_def_property_update(prop, NC_SCENE, NULL);
 
 	srna= RNA_def_struct(brna, "LineStyleGeometryModifier_TipRemover", "LineStyleGeometryModifier");
@@ -683,6 +692,42 @@ static void rna_def_linestyle_modifiers(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Offset", "Displacement that is applied to the main direction line along its normal");
 	RNA_def_property_update(prop, NC_SCENE, NULL);
 
+	srna= RNA_def_struct(brna, "LineStyleGeometryModifier_Blueprint", "LineStyleGeometryModifier");
+	RNA_def_struct_ui_text(srna, "Blueprint", "Produce a blueprint using circular, elliptic, and square contour strokes");
+	rna_def_geometry_modifier(srna);
+
+	prop= RNA_def_property(srna, "shape", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_bitflag_sdna(prop, NULL, "flags");
+	RNA_def_property_enum_items(prop, blueprint_shape_items);
+	RNA_def_property_ui_text(prop, "Shape", "Select the shape of blueprint contour strokes");
+	RNA_def_property_update(prop, NC_SCENE, NULL);
+
+	prop= RNA_def_property(srna, "rounds", PROP_INT, PROP_UNSIGNED);
+	RNA_def_property_int_sdna(prop, NULL, "rounds");
+	RNA_def_property_range(prop, 1, 1000);
+	RNA_def_property_ui_text(prop, "Rounds", "Number of rounds in contour strokes");
+	RNA_def_property_update(prop, NC_SCENE, NULL);
+
+	prop= RNA_def_property(srna, "backbone_length", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_float_sdna(prop, NULL, "backbone_length");
+	RNA_def_property_ui_text(prop, "Backbone Length", "Amount of backbone stretching");
+	RNA_def_property_update(prop, NC_SCENE, NULL);
+
+	prop= RNA_def_property(srna, "random_radius", PROP_INT, PROP_UNSIGNED);
+	RNA_def_property_int_sdna(prop, NULL, "random_radius");
+	RNA_def_property_ui_text(prop, "Random Radius", "Randomness of the radius");
+	RNA_def_property_update(prop, NC_SCENE, NULL);
+
+	prop= RNA_def_property(srna, "random_center", PROP_INT, PROP_UNSIGNED);
+	RNA_def_property_int_sdna(prop, NULL, "random_center");
+	RNA_def_property_ui_text(prop, "Random Center", "Randomness of the center");
+	RNA_def_property_update(prop, NC_SCENE, NULL);
+
+	prop= RNA_def_property(srna, "random_backbone", PROP_INT, PROP_UNSIGNED);
+	RNA_def_property_int_sdna(prop, NULL, "random_backbone");
+	RNA_def_property_ui_text(prop, "Random Backbone", "Randomness of the backbone stretching");
+	RNA_def_property_update(prop, NC_SCENE, NULL);
+
 }
 
 static void rna_def_linestyle(BlenderRNA *brna)