Cycles Hair: Introduction of Cardinal Spline Curve Segments and minor fixes.

The curve segment primitive has been added. This includes an intersection function and changes to the BVH.

A few small errors in the line segment intersection routine are also fixed.

3 files changed, 23 insertions, 8 deletions

diff --git a/intern/cycles/blender/addon/properties.py b/intern/cycles/blender/addon/properties.py
index 8b90b0bd4ff..9dfacf19c81 100644
--- a/intern/cycles/blender/addon/properties.py
+++ b/intern/cycles/blender/addon/properties.py
@@ -74,13 +74,14 @@ enum_curve_presets = (
 enum_curve_primitives = (
     ('TRIANGLES', "Triangles", "Create triangle geometry around strands"),
     ('LINE_SEGMENTS', "Line Segments", "Use line segment primitives"),
-    ('CURVE_SEGMENTS', "?Curve Segments?", "Use curve segment primitives (not implemented)"),
+    ('CURVE_SEGMENTS', "Curve Segments", "Use segmented cardinal curve primitives"),
+    ('CURVE_RIBBONS', "Curve Ribbons", "Use smooth cardinal curve ribbon primitives"),
     )
 
 enum_triangle_curves = (
-    ('CAMERA', "Planes", "Create individual triangles forming planes that face camera"),
-    ('RIBBONS', "Ribbons", "Create individual triangles forming ribbon"),
-    ('TESSELLATED', "Tessellated", "Create mesh surrounding each strand"),
+    ('CAMERA_TRIANGLES', "Planes", "Create individual triangles forming planes that face camera"),
+    ('RIBBON_TRIANGLES', "Ribbons", "Create individual triangles forming ribbon"),
+    ('TESSELLATED_TRIANGLES', "Tessellated", "Create mesh surrounding each strand"),
     )
 
 enum_line_curves = (
@@ -643,7 +644,7 @@ class CyclesCurveRenderSettings(bpy.types.PropertyGroup):
                 name="Mesh Geometry",
                 description="Method for creating triangle geometry",
                 items=enum_triangle_curves,
-                default='CAMERA',
+                default='CAMERA_TRIANGLES',
                 )
         cls.line_method = EnumProperty(
                 name="Intersection Method",
@@ -730,6 +731,12 @@ class CyclesCurveRenderSettings(bpy.types.PropertyGroup):
                 min=0, max=100.0,
                 default=1.01,
                 )
+        cls.subdivisions = IntProperty(
+                name="Subdivisions",
+                description="Number of subdivisions used in Cardinal curve intersection (power of 2)",
+                min=0, max=24,
+                default=3,
+                )
 
     @classmethod
     def unregister(cls):
diff --git a/intern/cycles/blender/addon/ui.py b/intern/cycles/blender/addon/ui.py
index a24da593b43..9767bd70f46 100644
--- a/intern/cycles/blender/addon/ui.py
+++ b/intern/cycles/blender/addon/ui.py
@@ -976,7 +976,7 @@ class CyclesRender_PT_CurveRendering(CyclesButtonsPanel, Panel):
         
             if cscene.primitive == 'TRIANGLES':
                 layout.prop(cscene, "triangle_method", text="Method")
-                if cscene.triangle_method == 'TESSELLATED':
+                if cscene.triangle_method == 'TESSELLATED_TRIANGLES':
                     layout.prop(cscene, "resolution", text="Resolution")
                 layout.prop(cscene, "use_smooth", text="Smooth")
             elif cscene.primitive == 'LINE_SEGMENTS':
@@ -997,6 +997,13 @@ class CyclesRender_PT_CurveRendering(CyclesButtonsPanel, Panel):
                 row = layout.row()
                 row.prop(cscene, "segments", text="Segments")
                 row.prop(cscene, "normalmix", text="Ray Mix")
+            elif cscene.primitive == 'CURVE_SEGMENTS' or cscene.primitive == 'CURVE_RIBBONS':
+                layout.prop(cscene, "subdivisions", text="Curve subdivisions")
+                layout.prop(cscene, "use_backfacing", text="Check back-faces")
+                
+                layout.prop(cscene, "interpolation", text="Interpolation")
+                row = layout.row()
+                row.prop(cscene, "segments", text="Segments")
             
             row = layout.row()
             row.prop(cscene, "use_cache", text="Export cache with children")
diff --git a/intern/cycles/blender/blender_curves.cpp b/intern/cycles/blender/blender_curves.cpp
index 41e1249dae7..f8795ec0a94 100644
--- a/intern/cycles/blender/blender_curves.cpp
+++ b/intern/cycles/blender/blender_curves.cpp
@@ -929,6 +929,7 @@ void BlenderSync::sync_curve_settings()
 		curve_system_manager->resolution = get_int(csscene, "resolution");
 		curve_system_manager->segments = get_int(csscene, "segments");
 		curve_system_manager->use_smooth = get_boolean(csscene, "use_smooth");
+		curve_system_manager->subdivisions = get_int(csscene, "subdivisions");
 
 		curve_system_manager->normalmix = get_float(csscene, "normalmix");
 		curve_system_manager->encasing_ratio = get_float(csscene, "encasing_ratio");
@@ -1055,11 +1056,11 @@ void BlenderSync::sync_curves(Mesh *mesh, BL::Mesh b_mesh, BL::Object b_ob, bool
 
 	if(primitive == CURVE_TRIANGLES){
 		int vert_num = mesh->triangles.size() * 3;
-		if(triangle_method == CURVE_CAMERA) {
+		if(triangle_method == CURVE_CAMERA_TRIANGLES) {
 			ExportCurveTrianglePlanes(mesh, &CData, interpolation, use_smooth, segments, RotCam);
 			ExportCurveTriangleUVs(mesh, &CData, interpolation, use_smooth, segments, vert_num, 1);
 		}
-		else if(triangle_method == CURVE_RIBBONS) {
+		else if(triangle_method == CURVE_RIBBON_TRIANGLES) {
 			ExportCurveTriangleRibbons(mesh, &CData, interpolation, use_smooth, segments);
 			ExportCurveTriangleUVs(mesh, &CData, interpolation, use_smooth, segments, vert_num, 1);
 		}