3 files changed, 42 insertions, 8 deletions

diff --git a/intern/cycles/blender/addon/properties.py b/intern/cycles/blender/addon/properties.py
index ac0a1d7bdb7..b0e0baf4057 100644
--- a/intern/cycles/blender/addon/properties.py
+++ b/intern/cycles/blender/addon/properties.py
@@ -71,6 +71,7 @@ enum_curve_presets = (
     ('TRUE_NORMAL', "True Normal", "Use true normals with line segments(good for thin strands)"),
     ('ACCURATE_PRESET', "Accurate", "Use best line segment settings (suitable for glass materials)"),
     ('SMOOTH_CURVES', "Smooth Curves", "Use smooth cardinal curves (slowest)"),
+    ('SMOOTH_RIBBONS', "Ribbons", "Use smooth cardinal curves without thickness"),
     )
 
 enum_curve_primitives = (
@@ -745,11 +746,23 @@ class CyclesCurveRenderSettings(bpy.types.PropertyGroup):
                 min=0, max=100.0,
                 default=1.01,
                 )
+        cls.minimum_width = FloatProperty(
+                name="Minimal width",
+                description="Minimal pixel width for strands (0 - deactivated)",
+                min=0, max=100,
+                default=0.0,
+                )
+        cls.maximum_width = FloatProperty(
+                name="Maximal width",
+                description="Maximum extension that strand radius can be increased by",
+                min=0, max=100,
+                default=0.1,
+                )
         cls.subdivisions = IntProperty(
                 name="Subdivisions",
                 description="Number of subdivisions used in Cardinal curve intersection (power of 2)",
                 min=0, max=24,
-                default=3,
+                default=4,
                 )
 
     @classmethod
@@ -765,15 +778,21 @@ class CyclesCurveSettings(bpy.types.PropertyGroup):
                 description="Cycles hair settings",
                 type=cls,
                 )
+        cls.radius_scale = FloatProperty(
+                name="Radius Scaling",
+                description="Multiplier of width properties",
+                min=0.0, max=1000.0,
+                default=0.01,
+                )
         cls.root_width = FloatProperty(
-                name="Root Size Multiplier",
-                description="Multiplier of particle size for the strand's width at root",
+                name="Root Size",
+                description="Strand's width at root",
                 min=0.0, max=1000.0,
                 default=1.0,
                 )
         cls.tip_width = FloatProperty(
-                name="Tip Size Multiplier",
-                description="Multiplier of particle size for the strand's width at tip",
+                name="Tip Multiplier",
+                description="Strand's width at tip",
                 min=0.0, max=1000.0,
                 default=0.0,
                 )
diff --git a/intern/cycles/blender/addon/ui.py b/intern/cycles/blender/addon/ui.py
index 564a62f257d..92e9c622201 100644
--- a/intern/cycles/blender/addon/ui.py
+++ b/intern/cycles/blender/addon/ui.py
@@ -1079,6 +1079,10 @@ class CyclesRender_PT_CurveRendering(CyclesButtonsPanel, Panel):
 
             row = layout.row()
             row.prop(ccscene, "use_parents", text="Include parents")
+        
+        row = layout.row()
+        row.prop(ccscene, "minimum_width", text="Min Pixels")
+        row.prop(ccscene, "maximum_width", text="Max Ext.")
 
 
 class CyclesParticle_PT_CurveSettings(CyclesButtonsPanel, Panel):
@@ -1103,12 +1107,15 @@ class CyclesParticle_PT_CurveSettings(CyclesButtonsPanel, Panel):
 
         row = layout.row()
         row.prop(cpsys, "shape", text="Shape")
-        row.prop(cpsys, "use_closetip", text="Close tip")
 
-        layout.label(text="Width multiplier:")
+        layout.label(text="Thickness:")
         row = layout.row()
         row.prop(cpsys, "root_width", text="Root")
         row.prop(cpsys, "tip_width", text="Tip")
+        
+        row = layout.row()
+        row.prop(cpsys, "radius_scale", text="Scaling")
+        row.prop(cpsys, "use_closetip", text="Close tip")
 
 
 class CyclesScene_PT_simplify(CyclesButtonsPanel, Panel):
diff --git a/intern/cycles/blender/blender_curves.cpp b/intern/cycles/blender/blender_curves.cpp
index 768a5a6ee3a..4e0aad8ad14 100644
--- a/intern/cycles/blender/blender_curves.cpp
+++ b/intern/cycles/blender/blender_curves.cpp
@@ -195,7 +195,7 @@ bool ObtainCacheParticleData(Mesh *mesh, BL::Mesh *b_mesh, BL::Object *b_ob, Par
 				CData->psys_curvenum.push_back(totcurves);
 				CData->psys_shader.push_back(shader);
 
-				float radius = b_psys.settings().particle_size() * 0.5f;
+				float radius = get_float(cpsys, "radius_scale") * 0.5f;
 	
 				CData->psys_rootradius.push_back(radius * get_float(cpsys, "root_width"));
 				CData->psys_tipradius.push_back(radius * get_float(cpsys, "tip_width"));
@@ -884,6 +884,8 @@ void BlenderSync::sync_curve_settings()
 	CurveSystemManager prev_curve_system_manager = *curve_system_manager;
 
 	curve_system_manager->use_curves = get_boolean(csscene, "use_curves");
+	curve_system_manager->minimum_width = get_float(csscene, "minimum_width");
+	curve_system_manager->maximum_width = get_float(csscene, "maximum_width");
 
 	if(preset == CURVE_CUSTOM) {
 		/*custom properties*/
@@ -957,6 +959,12 @@ void BlenderSync::sync_curve_settings()
 				curve_system_manager->use_backfacing = true;
 				curve_system_manager->subdivisions = 4;
 				break;
+			case CURVE_SMOOTH_RIBBONS:
+				/*Cardinal ribbons preset*/
+				curve_system_manager->primitive = CURVE_RIBBONS;
+				curve_system_manager->use_backfacing = false;
+				curve_system_manager->subdivisions = 4;
+				break;
 		}
 		
 	}