New feature

Patch [#33445] - Experimental Cycles Hair Rendering (CPU only)

This patch allows hair data to be exported to cycles and introduces a new line segment primitive to render with.

The UI appears under the particle tab and there is a new hair info node available.

It is only available under the experimental feature set and for cpu rendering.

12 files changed, 599 insertions, 20 deletions

diff --git a/intern/cycles/render/CMakeLists.txt b/intern/cycles/render/CMakeLists.txt
index 7907061c19c..d67a686d1e8 100644
--- a/intern/cycles/render/CMakeLists.txt
+++ b/intern/cycles/render/CMakeLists.txt
@@ -31,6 +31,7 @@ set(SRC
 	object.cpp
 	osl.cpp
 	particles.cpp
+	curves.cpp
 	scene.cpp
 	session.cpp
 	shader.cpp
@@ -56,6 +57,7 @@ set(SRC_HEADERS
 	object.h
 	osl.h
 	particles.h
+	curves.h
 	scene.h
 	session.h
 	shader.h
diff --git a/intern/cycles/render/curves.cpp b/intern/cycles/render/curves.cpp
new file mode 100644
index 00000000000..3299503b4ab
--- /dev/null
+++ b/intern/cycles/render/curves.cpp
@@ -0,0 +1,160 @@
+/*
+ * Copyright 2011, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "device.h"
+#include "curves.h"
+#include "mesh.h"
+#include "object.h"
+#include "scene.h"
+
+#include "util_foreach.h"
+#include "util_map.h"
+#include "util_progress.h"
+#include "util_vector.h"
+
+CCL_NAMESPACE_BEGIN
+
+/* Hair System Manager */
+
+CurveSystemManager::CurveSystemManager()
+{
+	primitive = CURVE_LINE_SEGMENTS;
+	line_method = CURVE_CORRECTED;
+	interpolation = CURVE_CARDINAL;
+	triangle_method = CURVE_CAMERA;
+	resolution = 3;
+	segments = 1;
+
+	normalmix = 1.0f;
+	encasing_ratio = 1.01f;
+
+	use_curves = true;
+	use_smooth = true;
+	use_cache = true;
+	use_parents = false;
+	use_encasing = true;
+	use_backfacing = false;
+	use_joined = false;
+	use_tangent_normal = false;
+	use_tangent_normal_geometry = false;
+	use_tangent_normal_correction = false;
+
+	need_update = true;
+	need_mesh_update = false;
+}
+
+CurveSystemManager::~CurveSystemManager()
+{
+}
+
+void CurveSystemManager::device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
+{
+	if(!need_update)
+		return;
+
+	device_free(device, dscene);
+
+	progress.set_status("Updating Hair settings", "Copying Hair settings to device");
+
+	KernelCurves *kcurve= &dscene->data.curve_kernel_data;
+
+	kcurve->curveflags = 0;
+
+	if(primitive == CURVE_SEGMENTS)
+		kcurve->curveflags |= CURVE_KN_INTERPOLATE;
+
+	if(line_method == CURVE_ACCURATE)
+		kcurve->curveflags |= CURVE_KN_ACCURATE;
+	if(line_method == CURVE_CORRECTED)
+		kcurve->curveflags |= CURVE_KN_INTERSECTCORRECTION;
+	if(line_method == CURVE_POSTCORRECTED)
+		kcurve->curveflags |= CURVE_KN_POSTINTERSECTCORRECTION;
+
+	if(use_tangent_normal)
+		kcurve->curveflags |= CURVE_KN_TANGENTGNORMAL;
+	if(use_tangent_normal_correction)
+		kcurve->curveflags |= CURVE_KN_NORMALCORRECTION;
+	if(use_tangent_normal_geometry)
+		kcurve->curveflags |= CURVE_KN_TRUETANGENTGNORMAL;
+	if(use_joined)
+		kcurve->curveflags |= CURVE_KN_CURVEDATA;
+	if(use_backfacing)
+		kcurve->curveflags |= CURVE_KN_BACKFACING;
+	if(use_encasing)
+		kcurve->curveflags |= CURVE_KN_ENCLOSEFILTER;
+
+	kcurve->normalmix = normalmix;
+	kcurve->encasing_ratio = encasing_ratio;
+
+	if(progress.get_cancel()) return;
+
+	need_update = false;
+}
+
+void CurveSystemManager::device_free(Device *device, DeviceScene *dscene)
+{
+
+}
+
+bool CurveSystemManager::modified(const CurveSystemManager& CurveSystemManager)
+{
+	return !(line_method == CurveSystemManager.line_method &&
+		interpolation == CurveSystemManager.interpolation &&
+		primitive == CurveSystemManager.primitive &&
+		use_encasing == CurveSystemManager.use_encasing &&
+		use_tangent_normal == CurveSystemManager.use_tangent_normal &&
+		use_tangent_normal_correction == CurveSystemManager.use_tangent_normal_correction &&
+		use_tangent_normal_geometry == CurveSystemManager.use_tangent_normal_geometry &&
+		encasing_ratio == CurveSystemManager.encasing_ratio &&
+		use_backfacing == CurveSystemManager.use_backfacing &&
+		normalmix == CurveSystemManager.normalmix &&
+		use_cache == CurveSystemManager.use_cache &&
+		use_smooth == CurveSystemManager.use_smooth &&
+		triangle_method == CurveSystemManager.triangle_method &&
+		resolution == CurveSystemManager.resolution &&
+		use_curves == CurveSystemManager.use_curves &&
+		use_joined == CurveSystemManager.use_joined &&
+		segments == CurveSystemManager.segments &&
+		use_parents == CurveSystemManager.use_parents);
+}
+
+bool CurveSystemManager::modified_mesh(const CurveSystemManager& CurveSystemManager)
+{
+	return !(primitive == CurveSystemManager.primitive &&
+		interpolation == CurveSystemManager.interpolation &&
+		use_parents == CurveSystemManager.use_parents &&
+		use_smooth == CurveSystemManager.use_smooth &&
+		triangle_method == CurveSystemManager.triangle_method &&
+		resolution == CurveSystemManager.resolution &&
+		use_curves == CurveSystemManager.use_curves &&
+		use_joined == CurveSystemManager.use_joined &&
+		segments == CurveSystemManager.segments &&
+		use_cache == CurveSystemManager.use_cache);
+}
+
+void CurveSystemManager::tag_update(Scene *scene)
+{
+	need_update = true;
+}
+
+void CurveSystemManager::tag_update_mesh()
+{
+	need_mesh_update = true;
+}
+CCL_NAMESPACE_END
+
diff --git a/intern/cycles/render/curves.h b/intern/cycles/render/curves.h
new file mode 100644
index 00000000000..581b3010d77
--- /dev/null
+++ b/intern/cycles/render/curves.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright 2011, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __CURVES_H__
+#define __CURVES_H__
+
+#include "util_types.h"
+#include "util_vector.h"
+
+CCL_NAMESPACE_BEGIN
+
+class Device;
+class DeviceScene;
+class Progress;
+class Scene;
+
+typedef enum curve_presets {
+	CURVE_CUSTOM,
+	CURVE_TANGENT_SHADING,
+	CURVE_TRUE_NORMAL,
+	CURVE_ACCURATE_PRESET
+} curve_presets;
+
+typedef enum curve_primitives {
+	CURVE_TRIANGLES,
+	CURVE_LINE_SEGMENTS,
+	CURVE_SEGMENTS
+} curve_primitives;
+
+typedef enum curve_triangles {
+	CURVE_CAMERA,
+	CURVE_RIBBONS,
+	CURVE_TESSELATED
+} curve_triangles;
+
+typedef enum curve_lines {
+	CURVE_ACCURATE,
+	CURVE_CORRECTED,
+	CURVE_POSTCORRECTED,
+	CURVE_UNCORRECTED
+} curve_lines;
+
+typedef enum curve_interpolation {
+	CURVE_LINEAR,
+	CURVE_CARDINAL,
+	CURVE_BSPLINE
+} curve_interpolation;
+
+class ParticleCurveData {
+
+public:
+
+	ParticleCurveData();
+	~ParticleCurveData();
+
+	vector<int> psys_firstcurve;
+	vector<int> psys_curvenum;
+	vector<int> psys_shader;
+
+	vector<float> psys_rootradius;
+	vector<float> psys_tipradius;
+	vector<float> psys_shape;
+	vector<bool> psys_closetip;
+
+	vector<int> curve_firstkey;
+	vector<int> curve_keynum;
+	vector<float> curve_length;
+	vector<float> curve_u;
+	vector<float> curve_v;
+
+	vector<float3> curvekey_co;
+	vector<float> curvekey_time;
+};
+
+/* HairSystem Manager */
+
+class CurveSystemManager {
+public:
+
+	int primitive;
+	int line_method;
+	int interpolation;
+	int triangle_method;
+	int resolution;
+	int segments;
+
+	float normalmix;
+	float encasing_ratio;
+
+	bool use_curves;
+	bool use_smooth;
+	bool use_cache;
+	bool use_parents;
+	bool use_encasing;
+	bool use_backfacing;
+	bool use_tangent_normal;
+	bool use_tangent_normal_correction;
+	bool use_tangent_normal_geometry;
+	bool use_joined;
+
+	bool need_update;
+	bool need_mesh_update;
+
+	CurveSystemManager();
+	~CurveSystemManager();
+
+	void device_update(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress);
+	void device_free(Device *device, DeviceScene *dscene);
+	bool modified(const CurveSystemManager& CurveSystemManager);
+	bool modified_mesh(const CurveSystemManager& CurveSystemManager);
+
+	void tag_update(Scene *scene);
+	void tag_update_mesh();
+};
+
+CCL_NAMESPACE_END
+
+#endif /* __CURVES_H__ */
+
diff --git a/intern/cycles/render/light.cpp b/intern/cycles/render/light.cpp
index 4173da453fd..66e528c7230 100644
--- a/intern/cycles/render/light.cpp
+++ b/intern/cycles/render/light.cpp
@@ -142,6 +142,7 @@ void LightManager::device_update_distribution(Device *device, DeviceScene *dscen
 	/* count */
 	size_t num_lights = scene->lights.size();
 	size_t num_triangles = 0;
+	size_t num_curve_segs = 0;
 
 	foreach(Object *object, scene->objects) {
 		Mesh *mesh = object->mesh;
@@ -169,10 +170,18 @@ void LightManager::device_update_distribution(Device *device, DeviceScene *dscen
 				if(shader->sample_as_light && shader->has_surface_emission)
 					num_triangles++;
 			}
+
+			/* disabled for strands*/
+			/*for(size_t i = 0; i < mesh->curve_segs.size(); i++) {
+			*	Shader *shader = scene->shaders[mesh->curve_segs[i].curveshader];
+			*
+			*	if(shader->sample_as_light && shader->has_surface_emission)
+			*		num_curve_segs++;
+			}*/
 		}
 	}
 
-	size_t num_distribution = num_triangles;
+	size_t num_distribution = num_triangles + num_curve_segs;
 	num_distribution += num_lights;
 
 	/* emission area */
@@ -234,6 +243,32 @@ void LightManager::device_update_distribution(Device *device, DeviceScene *dscen
 					totarea += triangle_area(p1, p2, p3);
 				}
 			}
+
+			/*sample as light disabled for strands*/
+			/*for(size_t i = 0; i < mesh->curve_segs.size(); i++) {
+			*	Shader *shader = scene->shaders[mesh->curve_segs[i].curveshader];
+			*
+			*	if(shader->sample_as_light && shader->has_surface_emission) {
+			*		distribution[offset].x = totarea;
+			*		distribution[offset].y = __int_as_float(i + mesh->curveseg_offset);
+			*		distribution[offset].z = 0.0f;
+			*		distribution[offset].w = __int_as_float(object_id);
+			*		offset++;
+			*
+			*		Mesh::CurveSeg s = mesh->curve_segs[i];
+			*		float3 p1 = mesh->curve_keys[s.v[0]].loc;
+			*		float r1 = mesh->curve_keys[s.v[0]].radius;
+			*		float3 p2 = mesh->curve_keys[s.v[1]].loc;
+			*		float r2 = mesh->curve_keys[s.v[1]].radius;
+			*
+			*		if(!transform_applied) {
+			*			p1 = transform_point(&tfm, p1);
+			*			p2 = transform_point(&tfm, p2);
+			*		}
+			*
+			*		totarea += M_PI_F * (r1 + r2) * len(p1 - p2);
+			*	}
+			}*/
 		}
 
 		if(progress.get_cancel()) return;
diff --git a/intern/cycles/render/mesh.cpp b/intern/cycles/render/mesh.cpp
index bc782a78c60..a2d545d51c0 100644
--- a/intern/cycles/render/mesh.cpp
+++ b/intern/cycles/render/mesh.cpp
@@ -51,6 +51,9 @@ Mesh::Mesh()
 	tri_offset = 0;
 	vert_offset = 0;
 
+	curveseg_offset = 0;
+	curvekey_offset = 0;
+
 	attributes.mesh = this;
 }
 
@@ -66,6 +69,7 @@ void Mesh::reserve(int numverts, int numtris)
 	triangles.resize(numtris);
 	shader.resize(numtris);
 	smooth.resize(numtris);
+	/*currently no need in hair segment resize and curve data needs including*/
 	attributes.reserve(numverts, numtris);
 }
 
@@ -77,6 +81,11 @@ void Mesh::clear()
 	shader.clear();
 	smooth.clear();
 
+	curve_keys.clear();
+	curve_keysCD.clear();
+	curve_segs.clear();
+	curve_attrib.clear();
+
 	attributes.clear();
 	used_shaders.clear();
 
@@ -96,14 +105,48 @@ void Mesh::add_triangle(int v0, int v1, int v2, int shader_, bool smooth_)
 	smooth.push_back(smooth_);
 }
 
+void Mesh::add_curvekey(float3 loc, float radius, float time)
+{
+	CurveKey ck;
+	ck.loc = loc;
+	ck.radius = radius;
+	ck.time = time;
+
+	curve_keys.push_back(ck);
+}
+
+void Mesh::add_curve(int v0, int v1, int shader, int curveid)
+{
+	CurveSeg s;
+	s.v[0] = v0;
+	s.v[1] = v1;
+	s.curveshader = shader;
+	s.curve = curveid;
+
+	curve_segs.push_back(s);
+}
+
+void Mesh::add_curveattrib(float u, float v)
+{
+	Curve_Attribute s;
+	s.uv[0] = u;
+	s.uv[1] = v;
+
+	curve_attrib.push_back(s);
+}
+
 void Mesh::compute_bounds()
 {
 	BoundBox bnds = BoundBox::empty;
 	size_t verts_size = verts.size();
+	size_t curve_keys_size = curve_keys.size();
 
 	for(size_t i = 0; i < verts_size; i++)
 		bnds.grow(verts[i]);
 
+	for(size_t i = 0; i < curve_keys_size; i++)
+		bnds.grow(curve_keys[i].loc, curve_keys[i].radius);
+
 	/* happens mostly on empty meshes */
 	if(!bnds.valid())
 		bnds.grow(make_float3(0.0f, 0.0f, 0.0f));
@@ -243,6 +286,45 @@ void Mesh::pack_verts(float4 *tri_verts, float4 *tri_vindex, size_t vert_offset)
 	}
 }
 
+void Mesh::pack_curves(Scene *scene, float4 *curve_key_co, float4 *curve_seg_keys, size_t curvekey_offset)
+{
+	size_t curve_keys_size = curve_keys.size();
+	CurveKey *keys_ptr = NULL;
+
+	if(curve_keys_size) {
+
+		keys_ptr = &curve_keys[0];
+
+		for(size_t i = 0; i < curve_keys_size; i++) {
+			float3 p = keys_ptr[i].loc;
+			curve_key_co[i] = make_float4(p.x, p.y, p.z, keys_ptr[i].radius);
+		}
+	}
+
+	size_t curve_seg_num = curve_segs.size();
+
+	if(curve_seg_num) {
+		CurveSeg *curve_ptr = &curve_segs[0];
+
+		int shader_id = 0;
+		
+		for(size_t i = 0; i < curve_seg_num; i++) {
+			CurveSeg s = curve_ptr[i];
+			shader_id = scene->shader_manager->get_shader_id(s.curveshader, this, false);
+
+			float3 p1 = keys_ptr[s.v[0]].loc;
+			float3 p2 = keys_ptr[s.v[1]].loc;
+			float length = len(p2 - p1);
+
+			curve_seg_keys[i] = make_float4(
+				__int_as_float(s.v[0] + curvekey_offset),
+				__int_as_float(s.v[1] + curvekey_offset),
+				__int_as_float(shader_id),
+				length);
+		}
+	}
+}
+
 void Mesh::compute_bvh(SceneParams *params, Progress *progress, int n, int total)
 {
 	if(progress->get_cancel())
@@ -573,39 +655,62 @@ void MeshManager::device_update_mesh(Device *device, DeviceScene *dscene, Scene
 	size_t vert_size = 0;
 	size_t tri_size = 0;
 
+	size_t CurveKey_size = 0;
+	size_t curve_seg_keys = 0;
+
 	foreach(Mesh *mesh, scene->meshes) {
 		mesh->vert_offset = vert_size;
 		mesh->tri_offset = tri_size;
 
+		mesh->curvekey_offset = CurveKey_size;
+		mesh->curveseg_offset = curve_seg_keys;
+
 		vert_size += mesh->verts.size();
 		tri_size += mesh->triangles.size();
+
+		CurveKey_size += mesh->curve_keys.size();
+		curve_seg_keys += mesh->curve_segs.size();
 	}
 
-	if(tri_size == 0)
-		return;
+	if(tri_size != 0) {
+		/* normals */
+		progress.set_status("Updating Mesh", "Computing normals");
 
-	/* normals */
-	progress.set_status("Updating Mesh", "Computing normals");
+		float4 *normal = dscene->tri_normal.resize(tri_size);
+		float4 *vnormal = dscene->tri_vnormal.resize(vert_size);
+		float4 *tri_verts = dscene->tri_verts.resize(vert_size);
+		float4 *tri_vindex = dscene->tri_vindex.resize(tri_size);
 
-	float4 *normal = dscene->tri_normal.resize(tri_size);
-	float4 *vnormal = dscene->tri_vnormal.resize(vert_size);
-	float4 *tri_verts = dscene->tri_verts.resize(vert_size);
-	float4 *tri_vindex = dscene->tri_vindex.resize(tri_size);
+		foreach(Mesh *mesh, scene->meshes) {
+			mesh->pack_normals(scene, &normal[mesh->tri_offset], &vnormal[mesh->vert_offset]);
+			mesh->pack_verts(&tri_verts[mesh->vert_offset], &tri_vindex[mesh->tri_offset], mesh->vert_offset);
 
-	foreach(Mesh *mesh, scene->meshes) {
-		mesh->pack_normals(scene, &normal[mesh->tri_offset], &vnormal[mesh->vert_offset]);
-		mesh->pack_verts(&tri_verts[mesh->vert_offset], &tri_vindex[mesh->tri_offset], mesh->vert_offset);
+			if(progress.get_cancel()) return;
+		}
 
-		if(progress.get_cancel()) return;
+		/* vertex coordinates */
+		progress.set_status("Updating Mesh", "Copying Mesh to device");
+
+		device->tex_alloc("__tri_normal", dscene->tri_normal);
+		device->tex_alloc("__tri_vnormal", dscene->tri_vnormal);
+		device->tex_alloc("__tri_verts", dscene->tri_verts);
+		device->tex_alloc("__tri_vindex", dscene->tri_vindex);
 	}
 
-	/* vertex coordinates */
-	progress.set_status("Updating Mesh", "Copying Mesh to device");
+	if(curve_seg_keys != 0) {
+		progress.set_status("Updating Mesh", "Copying Strands to device");
+
+		float4 *cur_keys = dscene->cur_keys.resize(CurveKey_size);
+		float4 *cur_segs = dscene->cur_segs.resize(curve_seg_keys);
 
-	device->tex_alloc("__tri_normal", dscene->tri_normal);
-	device->tex_alloc("__tri_vnormal", dscene->tri_vnormal);
-	device->tex_alloc("__tri_verts", dscene->tri_verts);
-	device->tex_alloc("__tri_vindex", dscene->tri_vindex);
+		foreach(Mesh *mesh, scene->meshes) {
+			mesh->pack_curves(scene, &cur_keys[mesh->curvekey_offset], &cur_segs[mesh->curveseg_offset], mesh->curvekey_offset);
+			if(progress.get_cancel()) return;
+		}
+
+		device->tex_alloc("__cur_keys", dscene->cur_keys);
+		device->tex_alloc("__cur_segs", dscene->cur_segs);
+	}
 }
 
 void MeshManager::device_update_bvh(Device *device, DeviceScene *dscene, Scene *scene, Progress& progress)
@@ -642,6 +747,10 @@ void MeshManager::device_update_bvh(Device *device, DeviceScene *dscene, Scene *
 		dscene->tri_woop.reference(&pack.tri_woop[0], pack.tri_woop.size());
 		device->tex_alloc("__tri_woop", dscene->tri_woop);
 	}
+	if(pack.prim_type.size()) {
+		dscene->prim_type.reference((uint*)&pack.prim_type[0], pack.prim_type.size());
+		device->tex_alloc("__prim_type", dscene->prim_type);
+	}
 	if(pack.prim_visibility.size()) {
 		dscene->prim_visibility.reference((uint*)&pack.prim_visibility[0], pack.prim_visibility.size());
 		device->tex_alloc("__prim_visibility", dscene->prim_visibility);
@@ -751,6 +860,7 @@ void MeshManager::device_free(Device *device, DeviceScene *dscene)
 	device->tex_free(dscene->bvh_nodes);
 	device->tex_free(dscene->object_node);
 	device->tex_free(dscene->tri_woop);
+	device->tex_free(dscene->prim_type);
 	device->tex_free(dscene->prim_visibility);
 	device->tex_free(dscene->prim_index);
 	device->tex_free(dscene->prim_object);
@@ -758,6 +868,8 @@ void MeshManager::device_free(Device *device, DeviceScene *dscene)
 	device->tex_free(dscene->tri_vnormal);
 	device->tex_free(dscene->tri_vindex);
 	device->tex_free(dscene->tri_verts);
+	device->tex_free(dscene->cur_segs);
+	device->tex_free(dscene->cur_keys);
 	device->tex_free(dscene->attributes_map);
 	device->tex_free(dscene->attributes_float);
 	device->tex_free(dscene->attributes_float3);
@@ -765,6 +877,7 @@ void MeshManager::device_free(Device *device, DeviceScene *dscene)
 	dscene->bvh_nodes.clear();
 	dscene->object_node.clear();
 	dscene->tri_woop.clear();
+	dscene->prim_type.clear();
 	dscene->prim_visibility.clear();
 	dscene->prim_index.clear();
 	dscene->prim_object.clear();
@@ -772,6 +885,8 @@ void MeshManager::device_free(Device *device, DeviceScene *dscene)
 	dscene->tri_vnormal.clear();
 	dscene->tri_vindex.clear();
 	dscene->tri_verts.clear();
+	dscene->cur_segs.clear();
+	dscene->cur_keys.clear();
 	dscene->attributes_map.clear();
 	dscene->attributes_float.clear();
 	dscene->attributes_float3.clear();
diff --git a/intern/cycles/render/mesh.h b/intern/cycles/render/mesh.h
index 637143f5adf..24d3f02e082 100644
--- a/intern/cycles/render/mesh.h
+++ b/intern/cycles/render/mesh.h
@@ -50,6 +50,28 @@ public:
 		int v[3];
 	};
 
+	/* Mesh Strand Data*/
+	struct CurveSeg {
+		int v[2];
+		uint curveshader;
+		int curve;
+	};
+
+	struct Curve_Attribute {
+		float uv[2];
+	};
+
+	struct CurveKey {
+		float3 loc;
+		float radius;
+		float time;
+	};
+
+	/*curve data for hair - currently only contains key tangent instead*/
+	struct CurveData {
+		float3 tg;
+	};
+
 	/* Displacement */
 	enum DisplacementMethod {
 		DISPLACE_BUMP,
@@ -65,6 +87,11 @@ public:
 	vector<uint> shader;
 	vector<bool> smooth;
 
+	vector<CurveKey> curve_keys;
+	vector<CurveData> curve_keysCD;
+	vector<CurveSeg> curve_segs;
+	vector<Curve_Attribute> curve_attrib;
+
 	vector<uint> used_shaders;
 	AttributeSet attributes;
 
@@ -82,6 +109,9 @@ public:
 	size_t tri_offset;
 	size_t vert_offset;
 
+	size_t curveseg_offset;
+	size_t curvekey_offset;
+
 	/* Functions */
 	Mesh();
 	~Mesh();
@@ -89,6 +119,9 @@ public:
 	void reserve(int numverts, int numfaces);
 	void clear();
 	void add_triangle(int v0, int v1, int v2, int shader, bool smooth);
+	void add_curvekey(float3 loc, float radius, float time);
+	void add_curve(int v0, int v1, int shader, int curveid);
+	void add_curveattrib(float u, float v);
 
 	void compute_bounds();
 	void add_face_normals();
@@ -96,6 +129,7 @@ public:
 
 	void pack_normals(Scene *scene, float4 *normal, float4 *vnormal);
 	void pack_verts(float4 *tri_verts, float4 *tri_vindex, size_t vert_offset);
+	void pack_curves(Scene *scene, float4 *curve_key_co, float4 *curve_seg_keys, size_t curvekey_offset);
 	void compute_bvh(SceneParams *params, Progress *progress, int n, int total);
 
 	bool need_attribute(Scene *scene, AttributeStandard std);
diff --git a/intern/cycles/render/nodes.cpp b/intern/cycles/render/nodes.cpp
index aef28449e44..23d6432616c 100644
--- a/intern/cycles/render/nodes.cpp
+++ b/intern/cycles/render/nodes.cpp
@@ -2240,6 +2240,52 @@ void ParticleInfoNode::compile(OSLCompiler& compiler)
 	compiler.add(this, "node_particle_info");
 }
 
+/* Hair Info */
+
+HairInfoNode::HairInfoNode()
+: ShaderNode("hair_info")
+{
+	add_output("Is Strand", SHADER_SOCKET_FLOAT);
+	add_output("Intercept", SHADER_SOCKET_FLOAT);
+	add_output("Thickness", SHADER_SOCKET_FLOAT);
+	add_output("Tangent Normal", SHADER_SOCKET_NORMAL);
+}
+
+void HairInfoNode::compile(SVMCompiler& compiler)
+{
+	ShaderOutput *out;
+	
+	out = output("Is Strand");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_HAIR_INFO, NODE_INFO_CURVE_IS_STRAND, out->stack_offset);
+	}
+
+	out = output("Intercept");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_HAIR_INFO, NODE_INFO_CURVE_INTERCEPT, out->stack_offset);
+	}
+
+	out = output("Thickness");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_HAIR_INFO, NODE_INFO_CURVE_THICKNESS, out->stack_offset);
+	}
+
+	out = output("Tangent Normal");
+	if(!out->links.empty()) {
+		compiler.stack_assign(out);
+		compiler.add_node(NODE_HAIR_INFO, NODE_INFO_CURVE_TANGENT_NORMAL, out->stack_offset);
+	}
+
+}
+
+void HairInfoNode::compile(OSLCompiler& compiler)
+{
+	compiler.add(this, "NODE_HAIR_INFO");
+}
+
 /* Value */
 
 ValueNode::ValueNode()
diff --git a/intern/cycles/render/nodes.h b/intern/cycles/render/nodes.h
index 8012a99ff05..ee7afccb0e1 100644
--- a/intern/cycles/render/nodes.h
+++ b/intern/cycles/render/nodes.h
@@ -331,6 +331,11 @@ public:
 	void attributes(AttributeRequestSet *attributes);
 };
 
+class HairInfoNode : public ShaderNode {
+public:
+	SHADER_NODE_CLASS(HairInfoNode)
+};
+
 class ValueNode : public ShaderNode {
 public:
 	SHADER_NODE_CLASS(ValueNode)
diff --git a/intern/cycles/render/object.cpp b/intern/cycles/render/object.cpp
index 5df8e8c1368..588b4d50e1b 100644
--- a/intern/cycles/render/object.cpp
+++ b/intern/cycles/render/object.cpp
@@ -19,6 +19,7 @@
 #include "device.h"
 #include "light.h"
 #include "mesh.h"
+#include "curves.h"
 #include "object.h"
 #include "scene.h"
 
@@ -45,6 +46,7 @@ Object::Object()
 	motion.post = transform_identity();
 	use_motion = false;
 	use_holdout = false;
+	curverender = false;
 }
 
 Object::~Object()
@@ -86,6 +88,13 @@ void Object::apply_transform()
 	for(size_t i = 0; i < mesh->verts.size(); i++)
 		mesh->verts[i] = transform_point(&tfm, mesh->verts[i]);
 
+	for(size_t i = 0; i < mesh->curve_keys.size(); i++)
+		mesh->curve_keys[i].loc = transform_point(&tfm, mesh->curve_keys[i].loc);
+
+	for(size_t i = 0; i < mesh->curve_keysCD.size(); i++)
+		mesh->curve_keysCD[i].tg = transform_direction(&tfm, mesh->curve_keysCD[i].tg);
+
+
 	Attribute *attr_fN = mesh->attributes.find(ATTR_STD_FACE_NORMAL);
 	Attribute *attr_vN = mesh->attributes.find(ATTR_STD_VERTEX_NORMAL);
 
@@ -133,6 +142,7 @@ void Object::tag_update(Scene *scene)
 		}
 	}
 
+	scene->curve_system_manager->need_update = true;
 	scene->mesh_manager->need_update = true;
 	scene->object_manager->need_update = true;
 }
@@ -189,6 +199,16 @@ void ObjectManager::device_update_transforms(Device *device, DeviceScene *dscene
 					surface_area += triangle_area(p1, p2, p3);
 				}
 
+				foreach(Mesh::CurveSeg& t, mesh->curve_segs) {
+					float3 p1 = mesh->curve_keys[t.v[0]].loc;
+					float r1 = mesh->curve_keys[t.v[0]].radius;
+					float3 p2 = mesh->curve_keys[t.v[1]].loc;
+					float r2 = mesh->curve_keys[t.v[1]].radius;
+
+					/* currently ignores segment overlaps*/
+					surface_area += M_PI_F *(r1 + r2) * len(p1 - p2);
+				}
+
 				surface_area_map[mesh] = surface_area;
 			}
 			else
@@ -204,6 +224,16 @@ void ObjectManager::device_update_transforms(Device *device, DeviceScene *dscene
 
 				surface_area += triangle_area(p1, p2, p3);
 			}
+
+			foreach(Mesh::CurveSeg& t, mesh->curve_segs) {
+				float3 p1 = mesh->curve_keys[t.v[0]].loc;
+				float r1 = mesh->curve_keys[t.v[0]].radius;
+				float3 p2 = mesh->curve_keys[t.v[1]].loc;
+				float r2 = mesh->curve_keys[t.v[1]].radius;
+
+				/* currently ignores segment overlaps*/
+				surface_area += M_PI_F *(r1 + r2) * len(p1 - p2);
+			}
 		}
 
 		/* pack in texture */
@@ -355,6 +385,7 @@ void ObjectManager::apply_static_transforms(Scene *scene, uint *object_flag, Pro
 void ObjectManager::tag_update(Scene *scene)
 {
 	need_update = true;
+	scene->curve_system_manager->need_update = true;
 	scene->mesh_manager->need_update = true;
 	scene->light_manager->need_update = true;
 }
diff --git a/intern/cycles/render/object.h b/intern/cycles/render/object.h
index 9c9b11bc29c..9ba500ca4d6 100644
--- a/intern/cycles/render/object.h
+++ b/intern/cycles/render/object.h
@@ -48,6 +48,7 @@ public:
 	MotionTransform motion;
 	bool use_motion;
 	bool use_holdout;
+	bool curverender;
 
 	float3 dupli_generated;
 	float2 dupli_uv;
diff --git a/intern/cycles/render/scene.cpp b/intern/cycles/render/scene.cpp
index 8085cfdd3e6..093bfecf88e 100644
--- a/intern/cycles/render/scene.cpp
+++ b/intern/cycles/render/scene.cpp
@@ -29,6 +29,7 @@
 #include "mesh.h"
 #include "object.h"
 #include "particles.h"
+#include "curves.h"
 #include "scene.h"
 #include "svm.h"
 #include "osl.h"
@@ -54,6 +55,7 @@ Scene::Scene(const SceneParams& params_, const DeviceInfo& device_info_)
 	integrator = new Integrator();
 	image_manager = new ImageManager();
 	particle_system_manager = new ParticleSystemManager();
+	curve_system_manager = new CurveSystemManager();
 
 	/* OSL only works on the CPU */
 	if(device_info_.type == DEVICE_CPU)
@@ -96,6 +98,7 @@ void Scene::free_memory(bool final)
 		light_manager->device_free(device, &dscene);
 
 		particle_system_manager->device_free(device, &dscene);
+		curve_system_manager->device_free(device, &dscene);
 
 		if(!params.persistent_images || final)
 			image_manager->device_free(device, &dscene);
@@ -112,6 +115,7 @@ void Scene::free_memory(bool final)
 		delete shader_manager;
 		delete light_manager;
 		delete particle_system_manager;
+		delete curve_system_manager;
 		delete image_manager;
 	}
 	else {
@@ -165,6 +169,11 @@ void Scene::device_update(Device *device_, Progress& progress)
 
 	if(progress.get_cancel()) return;
 
+	progress.set_status("Updating Hair Systems");
+	curve_system_manager->device_update(device, &dscene, this, progress);
+
+	if(progress.get_cancel()) return;
+
 	progress.set_status("Updating Meshes");
 	mesh_manager->device_update(device, &dscene, this, progress);
 
@@ -242,7 +251,8 @@ bool Scene::need_reset()
 		|| filter->need_update
 		|| integrator->need_update
 		|| shader_manager->need_update
-		|| particle_system_manager->need_update);
+		|| particle_system_manager->need_update
+		|| curve_system_manager->need_update);
 }
 
 void Scene::reset()
diff --git a/intern/cycles/render/scene.h b/intern/cycles/render/scene.h
index ebe932e40e7..8b121d3b2fb 100644
--- a/intern/cycles/render/scene.h
+++ b/intern/cycles/render/scene.h
@@ -50,6 +50,7 @@ class Object;
 class ObjectManager;
 class ParticleSystemManager;
 class ParticleSystem;
+class CurveSystemManager;
 class Shader;
 class ShaderManager;
 class Progress;
@@ -62,6 +63,7 @@ public:
 	device_vector<float4> bvh_nodes;
 	device_vector<uint> object_node;
 	device_vector<float4> tri_woop;
+	device_vector<uint> prim_type;
 	device_vector<uint> prim_visibility;
 	device_vector<uint> prim_index;
 	device_vector<uint> prim_object;
@@ -72,6 +74,9 @@ public:
 	device_vector<float4> tri_vindex;
 	device_vector<float4> tri_verts;
 
+	device_vector<float4> cur_segs;
+	device_vector<float4> cur_keys;
+
 	/* objects */
 	device_vector<float4> objects;
 	device_vector<float4> objects_vector;
@@ -170,6 +175,7 @@ public:
 	MeshManager *mesh_manager;
 	ObjectManager *object_manager;
 	ParticleSystemManager *particle_system_manager;
+	CurveSystemManager *curve_system_manager;
 
 	/* default shaders */
 	int default_surface;