Cycles:

* Revert r57203 (len() renaming)
There seems to be a problem with nVidia OpenCL after this and I haven't figured out the real cause yet. 
Better to selectively enable native length() later, after figuring out what's wrong. 

This fixes [#35612].

22 files changed, 75 insertions, 74 deletions

diff --git a/intern/cycles/blender/blender_curves.cpp b/intern/cycles/blender/blender_curves.cpp
index 7426471d95a..56d78fb5c26 100644
--- a/intern/cycles/blender/blender_curves.cpp
+++ b/intern/cycles/blender/blender_curves.cpp
@@ -224,7 +224,7 @@ bool ObtainCacheParticleData(Mesh *mesh, BL::Mesh *b_mesh, BL::Object *b_ob, Par
 						float3 cKey = make_float3(nco[0],nco[1],nco[2]);
 						cKey = transform_point(&itfm, cKey);
 						if(step_no > 0)
-							curve_length += length(cKey - pcKey);
+							curve_length += len(cKey - pcKey);
 						CData->curvekey_co.push_back(cKey);
 						CData->curvekey_time.push_back(curve_length);
 						pcKey = cKey;
@@ -473,7 +473,7 @@ void ExportCurveTriangleRibbons(Mesh *mesh, ParticleCurveData *CData, int interp
 		for( int curve = CData->psys_firstcurve[sys]; curve < CData->psys_firstcurve[sys] + CData->psys_curvenum[sys] ; curve++) {
 
 			float3 firstxbasis = cross(make_float3(1.0f,0.0f,0.0f),CData->curvekey_co[CData->curve_firstkey[curve]+1] - CData->curvekey_co[CData->curve_firstkey[curve]]);
-			if(length_squared(firstxbasis)!= 0.0f)
+			if(len_squared(firstxbasis)!= 0.0f)
 				firstxbasis = normalize(firstxbasis);
 			else
 				firstxbasis = normalize(cross(make_float3(0.0f,1.0f,0.0f),CData->curvekey_co[CData->curve_firstkey[curve]+1] - CData->curvekey_co[CData->curve_firstkey[curve]]));
@@ -499,7 +499,7 @@ void ExportCurveTriangleRibbons(Mesh *mesh, ParticleCurveData *CData, int interp
 
 				xbasis = cross(v1,v2);
 
-				if(length_squared(xbasis) >= 0.05f * length_squared(v1) * length_squared(v2)) {
+				if(len_squared(xbasis) >= 0.05f * len_squared(v1) * len_squared(v2)) {
 					firstxbasis = normalize(xbasis);
 					break;
 				}
@@ -528,7 +528,7 @@ void ExportCurveTriangleRibbons(Mesh *mesh, ParticleCurveData *CData, int interp
 
 				xbasis = cross(v1,v2);
 
-				if(length_squared(xbasis) >= 0.05f * length_squared(v1) * length_squared(v2)) {
+				if(len_squared(xbasis) >= 0.05f * len_squared(v1) * len_squared(v2)) {
 					xbasis = normalize(xbasis);
 					firstxbasis = xbasis;
 				}
@@ -586,7 +586,7 @@ void ExportCurveTriangleGeometry(Mesh *mesh, ParticleCurveData *CData, int inter
 		for( int curve = CData->psys_firstcurve[sys]; curve < CData->psys_firstcurve[sys] + CData->psys_curvenum[sys] ; curve++) {
 
 			float3 firstxbasis = cross(make_float3(1.0f,0.0f,0.0f),CData->curvekey_co[CData->curve_firstkey[curve]+1] - CData->curvekey_co[CData->curve_firstkey[curve]]);
-			if(length_squared(firstxbasis)!= 0.0f)
+			if(len_squared(firstxbasis)!= 0.0f)
 				firstxbasis = normalize(firstxbasis);
 			else
 				firstxbasis = normalize(cross(make_float3(0.0f,1.0f,0.0f),CData->curvekey_co[CData->curve_firstkey[curve]+1] - CData->curvekey_co[CData->curve_firstkey[curve]]));
@@ -613,7 +613,7 @@ void ExportCurveTriangleGeometry(Mesh *mesh, ParticleCurveData *CData, int inter
 
 				xbasis = cross(v1,v2);
 
-				if(length_squared(xbasis) >= 0.05f * length_squared(v1) * length_squared(v2)) {
+				if(len_squared(xbasis) >= 0.05f * len_squared(v1) * len_squared(v2)) {
 					firstxbasis = normalize(xbasis);
 					break;
 				}
@@ -643,7 +643,7 @@ void ExportCurveTriangleGeometry(Mesh *mesh, ParticleCurveData *CData, int inter
 
 				xbasis = cross(v1,v2);
 
-				if(length_squared(xbasis) >= 0.05f * length_squared(v1) * length_squared(v2)) {
+				if(len_squared(xbasis) >= 0.05f * len_squared(v1) * len_squared(v2)) {
 					xbasis = normalize(xbasis);
 					firstxbasis = xbasis;
 				}
diff --git a/intern/cycles/blender/blender_mesh.cpp b/intern/cycles/blender/blender_mesh.cpp
index 28d89e6fdc3..d628fa04f92 100644
--- a/intern/cycles/blender/blender_mesh.cpp
+++ b/intern/cycles/blender/blender_mesh.cpp
@@ -237,8 +237,8 @@ static void create_mesh(Scene *scene, Mesh *mesh, BL::Mesh b_mesh, const vector<
 		bool smooth = f->use_smooth();
 
 		if(n == 4) {
-			if(length_squared(cross(mesh->verts[vi[1]] - mesh->verts[vi[0]], mesh->verts[vi[2]] - mesh->verts[vi[0]])) == 0.0f ||
-				length_squared(cross(mesh->verts[vi[2]] - mesh->verts[vi[0]], mesh->verts[vi[3]] - mesh->verts[vi[0]])) == 0.0f) {
+			if(len_squared(cross(mesh->verts[vi[1]] - mesh->verts[vi[0]], mesh->verts[vi[2]] - mesh->verts[vi[0]])) == 0.0f ||
+				len_squared(cross(mesh->verts[vi[2]] - mesh->verts[vi[0]], mesh->verts[vi[3]] - mesh->verts[vi[0]])) == 0.0f) {
 				mesh->add_triangle(vi[0], vi[1], vi[3], shader, smooth);
 				mesh->add_triangle(vi[2], vi[3], vi[1], shader, smooth);
 			}
diff --git a/intern/cycles/bvh/bvh.cpp b/intern/cycles/bvh/bvh.cpp
index 983d6fbce3e..82a444bda76 100644
--- a/intern/cycles/bvh/bvh.cpp
+++ b/intern/cycles/bvh/bvh.cpp
@@ -287,7 +287,7 @@ void BVH::pack_curve_segment(int idx, float4 woop[3])
 	float3 v1 = mesh->curve_keys[k1].co;
 
 	float3 d0 = v1 - v0;
-	float l =  length(d0);
+	float l =  len(d0);
 	
 	/*Plan
 	*Transform tfm = make_transform(
diff --git a/intern/cycles/kernel/kernel_bvh.h b/intern/cycles/kernel/kernel_bvh.h
index 1b02e486b40..aff9d586e7a 100644
--- a/intern/cycles/kernel/kernel_bvh.h
+++ b/intern/cycles/kernel/kernel_bvh.h
@@ -64,7 +64,7 @@ __device_inline void bvh_instance_push(KernelGlobals *kg, int object, const Ray
 	float3 dir = transform_direction(&tfm, ray->D);
 
 	float len;
-	dir = normalize_length(dir, &len);
+	dir = normalize_len(dir, &len);
 
 	*idir = bvh_inverse_direction(dir);
 
@@ -76,7 +76,7 @@ __device_inline void bvh_instance_pop(KernelGlobals *kg, int object, const Ray *
 {
 	if(*t != FLT_MAX) {
 		Transform tfm = object_fetch_transform(kg, object, OBJECT_TRANSFORM);
-		*t *= length(transform_direction(&tfm, 1.0f/(*idir)));
+		*t *= len(transform_direction(&tfm, 1.0f/(*idir)));
 	}
 
 	*P = ray->P;
@@ -94,7 +94,7 @@ __device_inline void bvh_instance_motion_push(KernelGlobals *kg, int object, con
 	float3 dir = transform_direction(&itfm, ray->D);
 
 	float len;
-	dir = normalize_length(dir, &len);
+	dir = normalize_len(dir, &len);
 
 	*idir = bvh_inverse_direction(dir);
 
@@ -105,7 +105,7 @@ __device_inline void bvh_instance_motion_push(KernelGlobals *kg, int object, con
 __device_inline void bvh_instance_motion_pop(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *idir, float *t, Transform *tfm, const float tmax)
 {
 	if(*t != FLT_MAX)
-		*t *= length(transform_direction(tfm, 1.0f/(*idir)));
+		*t *= len(transform_direction(tfm, 1.0f/(*idir)));
 
 	*P = ray->P;
 	*idir = bvh_inverse_direction(ray->D);
@@ -489,14 +489,14 @@ __device_inline void bvh_cardinal_curve_intersect(KernelGlobals *kg, Intersectio
 				t = p_curr.z;
 			}
 			else {
-				float l = length(p_en - p_st);
+				float l = len(p_en - p_st);
 				/*minimum width extension*/
 				float or1 = r1;
 				float or2 = r2;
 				if(difl != 0.0f) {
-					mw_extension = min(length(p_st - P) * difl, extmax);
+					mw_extension = min(len(p_st - P) * difl, extmax);
 					or1 = r1 < mw_extension ? mw_extension : r1;
-					mw_extension = min(length(p_en - P) * difl, extmax);
+					mw_extension = min(len(p_en - P) * difl, extmax);
 					or2 = r2 < mw_extension ? mw_extension : r2;
 				}
 				/* --- */
@@ -611,9 +611,9 @@ __device_inline void bvh_curve_intersect(KernelGlobals *kg, Intersection *isect,
 	float r1 = or1;
 	float r2 = or2;
 	if(difl != 0.0f) {
-		float pixelsize = min(length(p1 - P) * difl, extmax);
+		float pixelsize = min(len(p1 - P) * difl, extmax);
 		r1 = or1 < pixelsize ? pixelsize : or1;
-		pixelsize = min(length(p2 - P) * difl, extmax);
+		pixelsize = min(len(p2 - P) * difl, extmax);
 		r2 = or2 < pixelsize ? pixelsize : or2;
 	}
 	/* --- */
@@ -621,14 +621,14 @@ __device_inline void bvh_curve_intersect(KernelGlobals *kg, Intersection *isect,
 	float mr = max(r1,r2);
 	float3 dif = P - p1;
 	float3 dir = 1.0f/idir;
-	float l = length(p2 - p1);
+	float l = len(p2 - p1);
 
 	float sp_r = mr + 0.5f * l;
 	float3 sphere_dif = P - ((p1 + p2) * 0.5f);
 	float sphere_b = dot(dir,sphere_dif);
 	sphere_dif = sphere_dif - sphere_b * dir;
 	sphere_b = dot(dir,sphere_dif);
-	float sdisc = sphere_b * sphere_b - length_squared(sphere_dif) + sp_r * sp_r;
+	float sdisc = sphere_b * sphere_b - len_squared(sphere_dif) + sp_r * sp_r;
 	if(sdisc < 0.0f)
 		return;
 
@@ -652,8 +652,8 @@ __device_inline void bvh_curve_intersect(KernelGlobals *kg, Intersection *isect,
 	/* test minimum separation*/
 	float3 cprod = cross(tg, dir);
 	float3 cprod2 = cross(tg, dif);
-	float cprodsq = length_squared(cprod);
-	float cprod2sq = length_squared(cprod2);
+	float cprodsq = len_squared(cprod);
+	float cprod2sq = len_squared(cprod2);
 	float distscaled = dot(cprod,dif);
 
 	if(cprodsq == 0)
@@ -1010,7 +1010,7 @@ __device_inline float3 bvh_triangle_refine(KernelGlobals *kg, ShaderData *sd, co
 
 		P = transform_point(&tfm, P);
 		D = transform_direction(&tfm, D*t);
-		D = normalize_length(D, &t);
+		D = normalize_len(D, &t);
 	}
 
 	P = P + D*t;
@@ -1080,7 +1080,7 @@ __device_inline float3 bvh_curve_refine(KernelGlobals *kg, ShaderData *sd, const
 
 		P = transform_point(&tfm, P);
 		D = transform_direction(&tfm, D*t);
-		D = normalize_length(D, &t);
+		D = normalize_len(D, &t);
 	}
 
 	int prim = kernel_tex_fetch(__prim_index, isect->prim);
@@ -1092,7 +1092,7 @@ __device_inline float3 bvh_curve_refine(KernelGlobals *kg, ShaderData *sd, const
 	float4 P1 = kernel_tex_fetch(__curve_keys, k0);
 	float4 P2 = kernel_tex_fetch(__curve_keys, k1);
 	float l = 1.0f;
-	float3 tg = normalize_length(float4_to_float3(P2 - P1),&l);
+	float3 tg = normalize_len(float4_to_float3(P2 - P1),&l);
 	float r1 = P1.w;
 	float r2 = P2.w;
 	float gd = ((r2 - r1)/l);
diff --git a/intern/cycles/kernel/kernel_camera.h b/intern/cycles/kernel/kernel_camera.h
index 33456886990..a23586a53a4 100644
--- a/intern/cycles/kernel/kernel_camera.h
+++ b/intern/cycles/kernel/kernel_camera.h
@@ -255,7 +255,7 @@ __device_inline float camera_distance(KernelGlobals *kg, float3 P)
 		return fabsf(dot((P - camP), camD));
 	}
 	else
-		return length(P - camP);
+		return len(P - camP);
 }
 
 CCL_NAMESPACE_END
diff --git a/intern/cycles/kernel/kernel_curve.h b/intern/cycles/kernel/kernel_curve.h
index f1b9682f04f..e065717888c 100644
--- a/intern/cycles/kernel/kernel_curve.h
+++ b/intern/cycles/kernel/kernel_curve.h
@@ -122,7 +122,7 @@ __device float3 curve_tangent_normal(KernelGlobals *kg, ShaderData *sd)
 	if(sd->segment != ~0) {
 		float normalmix = kernel_data.curve_kernel_data.normalmix;
 
-		tgN = -(-sd->I - sd->dPdu * (dot(sd->dPdu,-sd->I) * normalmix / length_squared(sd->dPdu)));
+		tgN = -(-sd->I - sd->dPdu * (dot(sd->dPdu,-sd->I) * normalmix / len_squared(sd->dPdu)));
 		tgN = normalize(tgN);
 
 		/* need to find suitable scaled gd for corrected normal */
diff --git a/intern/cycles/kernel/kernel_emission.h b/intern/cycles/kernel/kernel_emission.h
index 42e5f3961cd..74f768c899c 100644
--- a/intern/cycles/kernel/kernel_emission.h
+++ b/intern/cycles/kernel/kernel_emission.h
@@ -133,7 +133,7 @@ __device_noinline bool direct_emission(KernelGlobals *kg, ShaderData *sd, int li
 		else {
 			/* other lights, avoid self-intersection */
 			ray->D = ray_offset(ls.P, ls.Ng) - ray->P;
-			ray->D = normalize_length(ray->D, &ray->t);
+			ray->D = normalize_len(ray->D, &ray->t);
 		}
 
 		ray->dP = sd->dP;
diff --git a/intern/cycles/kernel/kernel_light.h b/intern/cycles/kernel/kernel_light.h
index f5899b90b26..d4d78e413d2 100644
--- a/intern/cycles/kernel/kernel_light.h
+++ b/intern/cycles/kernel/kernel_light.h
@@ -263,7 +263,7 @@ __device void lamp_light_sample(KernelGlobals *kg, int lamp,
 				/* sphere light */
 				ls->P += sphere_light_sample(P, ls->P, radius, randu, randv);
 
-			ls->D = normalize_length(ls->P - P, &ls->t);
+			ls->D = normalize_len(ls->P - P, &ls->t);
 			ls->Ng = -ls->D;
 
 			float invarea = data1.z;
@@ -287,7 +287,7 @@ __device void lamp_light_sample(KernelGlobals *kg, int lamp,
 
 			ls->P += area_light_sample(axisu, axisv, randu, randv);
 			ls->Ng = D;
-			ls->D = normalize_length(ls->P - P, &ls->t);
+			ls->D = normalize_len(ls->P - P, &ls->t);
 
 			float invarea = data2.x;
 
@@ -487,7 +487,7 @@ __device void curve_segment_light_sample(KernelGlobals *kg, int prim, int object
 	float4 P1 = kernel_tex_fetch(__curve_keys, k0);
 	float4 P2 = kernel_tex_fetch(__curve_keys, k1);
 
-	float l = length(float4_to_float3(P2) - float4_to_float3(P1));
+	float l = len(float4_to_float3(P2) - float4_to_float3(P1));
 
 	float r1 = P1.w;
 	float r2 = P2.w;
@@ -569,7 +569,7 @@ __device void light_sample(KernelGlobals *kg, float randt, float randu, float ra
 			triangle_light_sample(kg, prim, object, randu, randv, time, ls);
 
 		/* compute incoming direction, distance and pdf */
-		ls->D = normalize_length(ls->P - P, &ls->t);
+		ls->D = normalize_len(ls->P - P, &ls->t);
 		ls->pdf = triangle_light_pdf(kg, ls->Ng, -ls->D, ls->t);
 	}
 	else {
diff --git a/intern/cycles/kernel/kernel_path.h b/intern/cycles/kernel/kernel_path.h
index 5d02f059ec8..d2de9ba2b44 100644
--- a/intern/cycles/kernel/kernel_path.h
+++ b/intern/cycles/kernel/kernel_path.h
@@ -222,7 +222,7 @@ __device_inline bool shadow_blocked(KernelGlobals *kg, PathState *state, Ray *ra
 
 				ray->P = ray_offset(sd.P, -sd.Ng);
 				if(ray->t != FLT_MAX)
-					ray->D = normalize_length(Pend - ray->P, &ray->t);
+					ray->D = normalize_len(Pend - ray->P, &ray->t);
 
 				bounce++;
 			}
@@ -266,7 +266,7 @@ __device float4 kernel_path_progressive(KernelGlobals *kg, RNG *rng, int sample,
 			if((kernel_data.cam.resolution == 1) && (state.flag & PATH_RAY_CAMERA)) {	
 				float3 pixdiff = ray.dD.dx + ray.dD.dy;
 				/*pixdiff = pixdiff - dot(pixdiff, ray.D)*ray.D;*/
-				difl = kernel_data.curve_kernel_data.minimum_width * length(pixdiff) * 0.5f;
+				difl = kernel_data.curve_kernel_data.minimum_width * len(pixdiff) * 0.5f;
 			}
 
 			extmax = kernel_data.curve_kernel_data.maximum_width;
@@ -957,7 +957,7 @@ __device float4 kernel_path_non_progressive(KernelGlobals *kg, RNG *rng, int sam
 			if((kernel_data.cam.resolution == 1) && (state.flag & PATH_RAY_CAMERA)) {	
 				float3 pixdiff = ray.dD.dx + ray.dD.dy;
 				/*pixdiff = pixdiff - dot(pixdiff, ray.D)*ray.D;*/
-				difl = kernel_data.curve_kernel_data.minimum_width * length(pixdiff) * 0.5f;
+				difl = kernel_data.curve_kernel_data.minimum_width * len(pixdiff) * 0.5f;
 			}
 
 			extmax = kernel_data.curve_kernel_data.maximum_width;
diff --git a/intern/cycles/kernel/kernel_subsurface.h b/intern/cycles/kernel/kernel_subsurface.h
index f3b7c014d99..f7bccf71976 100644
--- a/intern/cycles/kernel/kernel_subsurface.h
+++ b/intern/cycles/kernel/kernel_subsurface.h
@@ -201,7 +201,7 @@ __device void subsurface_scatter_step(KernelGlobals *kg, ShaderData *sd, int sta
 		/* create ray */
 		Ray ray;
 		ray.P = p1;
-		ray.D = normalize_length(p2 - p1, &ray.t);
+		ray.D = normalize_len(p2 - p1, &ray.t);
 		ray.dP = sd->dP;
 		ray.dD = differential3_zero();
 		ray.time = sd->time;
diff --git a/intern/cycles/kernel/svm/svm_camera.h b/intern/cycles/kernel/svm/svm_camera.h
index 972d14d00e2..f13cefb7764 100644
--- a/intern/cycles/kernel/svm/svm_camera.h
+++ b/intern/cycles/kernel/svm/svm_camera.h
@@ -27,7 +27,7 @@ __device void svm_node_camera(KernelGlobals *kg, ShaderData *sd, float *stack, u
 	Transform tfm = kernel_data.cam.worldtocamera;
 	vector = transform_point(&tfm, sd->P);
 	zdepth = vector.z;
-	distance = length(vector);
+	distance = len(vector);
 
 	if (stack_valid(out_vector))
 		stack_store_float3(stack, out_vector, normalize(vector));
diff --git a/intern/cycles/kernel/svm/svm_math.h b/intern/cycles/kernel/svm/svm_math.h
index 93d432e5954..dbf477a0a96 100644
--- a/intern/cycles/kernel/svm/svm_math.h
+++ b/intern/cycles/kernel/svm/svm_math.h
@@ -82,7 +82,7 @@ __device void svm_vector_math(float *Fac, float3 *Vector, NodeVectorMath type, f
 		*Fac = average_fac(*Vector);
 	}
 	else if(type == NODE_VECTOR_MATH_AVERAGE) {
-		*Fac = length(Vector1 + Vector2);
+		*Fac = len(Vector1 + Vector2);
 		*Vector = normalize(Vector1 + Vector2);
 	}
 	else if(type == NODE_VECTOR_MATH_DOT_PRODUCT) {
@@ -91,11 +91,11 @@ __device void svm_vector_math(float *Fac, float3 *Vector, NodeVectorMath type, f
 	}
 	else if(type == NODE_VECTOR_MATH_CROSS_PRODUCT) {
 		float3 c = cross(Vector1, Vector2);
-		*Fac = length(c);
+		*Fac = len(c);
 		*Vector = normalize(c);
 	}
 	else if(type == NODE_VECTOR_MATH_NORMALIZE) {
-		*Fac = length(Vector1);
+		*Fac = len(Vector1);
 		*Vector = normalize(Vector1);
 	}
 	else {
diff --git a/intern/cycles/kernel/svm/svm_texture.h b/intern/cycles/kernel/svm/svm_texture.h
index 67e08bad7f8..a4f6691435c 100644
--- a/intern/cycles/kernel/svm/svm_texture.h
+++ b/intern/cycles/kernel/svm/svm_texture.h
@@ -25,7 +25,7 @@ __device float voronoi_distance(NodeDistanceMetric distance_metric, float3 d, fl
 	if(distance_metric == NODE_VORONOI_DISTANCE_SQUARED)
 		return dot(d, d);
 	if(distance_metric == NODE_VORONOI_ACTUAL_DISTANCE)
-		return length(d);
+		return len(d);
 	if(distance_metric == NODE_VORONOI_MANHATTAN)
 		return fabsf(d.x) + fabsf(d.y) + fabsf(d.z);
 	if(distance_metric == NODE_VORONOI_CHEBYCHEV)
diff --git a/intern/cycles/kernel/svm/svm_wave.h b/intern/cycles/kernel/svm/svm_wave.h
index e37b0788361..d2d808e4063 100644
--- a/intern/cycles/kernel/svm/svm_wave.h
+++ b/intern/cycles/kernel/svm/svm_wave.h
@@ -29,7 +29,7 @@ __device_noinline float svm_wave(NodeWaveType type, float3 p, float scale, float
 	if(type == NODE_WAVE_BANDS)
 		n = (p.x + p.y + p.z) * 10.0f;
 	else /* if(type == NODE_WAVE_RINGS) */
-		n = length(p) * 20.0f;
+		n = len(p) * 20.0f;
 	
 	if(distortion != 0.0f)
 		n += distortion * noise_turbulence(p*dscale, NODE_NOISE_PERLIN, detail, 0);
diff --git a/intern/cycles/kernel/svm/svm_wireframe.h b/intern/cycles/kernel/svm/svm_wireframe.h
index 24b29058440..9ecb81847d7 100644
--- a/intern/cycles/kernel/svm/svm_wireframe.h
+++ b/intern/cycles/kernel/svm/svm_wireframe.h
@@ -66,8 +66,8 @@ __device void svm_node_wireframe(KernelGlobals *kg, ShaderData *sd, float *stack
 		if(pixel_size) {
 			// Project the derivatives of P to the viewing plane defined
 			// by I so we have a measure of how big is a pixel at this point
-			float pixelwidth_x = length(sd->dP.dx - dot(sd->dP.dx, sd->I) * sd->I);
-			float pixelwidth_y = length(sd->dP.dy - dot(sd->dP.dy, sd->I) * sd->I);
+			float pixelwidth_x = len(sd->dP.dx - dot(sd->dP.dx, sd->I) * sd->I);
+			float pixelwidth_y = len(sd->dP.dy - dot(sd->dP.dy, sd->I) * sd->I);
 			// Take the average of both axis' length
 			pixelwidth = (pixelwidth_x + pixelwidth_y) * 0.5f;
 		}
diff --git a/intern/cycles/render/light.cpp b/intern/cycles/render/light.cpp
index f29061299b5..1d2acf79b6c 100644
--- a/intern/cycles/render/light.cpp
+++ b/intern/cycles/render/light.cpp
@@ -276,7 +276,7 @@ void LightManager::device_update_distribution(Device *device, DeviceScene *dscen
 							p2 = transform_point(&tfm, p2);
 						}
 				
-						totarea += M_PI_F * (r1 + r2) * length(p1 - p2);
+						totarea += M_PI_F * (r1 + r2) * len(p1 - p2);
 					}
 				}
 
@@ -547,7 +547,7 @@ void LightManager::device_update_points(Device *device, DeviceScene *dscene, Sce
 		else if(light->type == LIGHT_AREA) {
 			float3 axisu = light->axisu*(light->sizeu*light->size);
 			float3 axisv = light->axisv*(light->sizev*light->size);
-			float area = length(axisu)*length(axisv);
+			float area = len(axisu)*len(axisv);
 			float invarea = (area > 0.0f)? 1.0f/area: 1.0f;
 
 			if(light->use_mis && area > 0.0f)
diff --git a/intern/cycles/render/mesh.cpp b/intern/cycles/render/mesh.cpp
index 8ec2514bbfe..4a2a64bb0f3 100644
--- a/intern/cycles/render/mesh.cpp
+++ b/intern/cycles/render/mesh.cpp
@@ -187,7 +187,7 @@ void Mesh::add_face_normals()
 			float3 v2 = verts_ptr[t.v[2]];
 
 			float3 norm = cross(v1 - v0, v2 - v0);
-			float normlen = length(norm);
+			float normlen = len(norm);
 			if(normlen == 0.0f)
 				fN[i] = make_float3(0.0f, 0.0f, 0.0f);
 			else
diff --git a/intern/cycles/render/object.cpp b/intern/cycles/render/object.cpp
index cd266367b6f..1a2780995e3 100644
--- a/intern/cycles/render/object.cpp
+++ b/intern/cycles/render/object.cpp
@@ -200,7 +200,7 @@ void ObjectManager::device_update_transforms(Device *device, DeviceScene *dscene
 						float r2 = mesh->curve_keys[first_key + i + 1].radius;
 
 						/* currently ignores segment overlaps*/
-						surface_area += M_PI_F *(r1 + r2) * length(p1 - p2);
+						surface_area += M_PI_F *(r1 + r2) * len(p1 - p2);
 					}
 				}
 
@@ -233,7 +233,7 @@ void ObjectManager::device_update_transforms(Device *device, DeviceScene *dscene
 					p2 = transform_point(&tfm, p2);
 
 					/* currently ignores segment overlaps*/
-					surface_area += M_PI_F *(r1 + r2) * length(p1 - p2);
+					surface_area += M_PI_F *(r1 + r2) * len(p1 - p2);
 				}
 			}
 		}
diff --git a/intern/cycles/subd/subd_dice.cpp b/intern/cycles/subd/subd_dice.cpp
index 0174c139b01..48e6808bc38 100644
--- a/intern/cycles/subd/subd_dice.cpp
+++ b/intern/cycles/subd/subd_dice.cpp
@@ -98,8 +98,8 @@ void EdgeDice::stitch_triangles(vector<int>& outer, vector<int>& inner)
 		}
 		else {
 			/* length of diagonals */
-			float len1 = length(mesh_P[inner[i]] - mesh_P[outer[j+1]]);
-			float len2 = length(mesh_P[outer[j]] - mesh_P[inner[i+1]]);
+			float len1 = len(mesh_P[inner[i]] - mesh_P[outer[j+1]]);
+			float len2 = len(mesh_P[outer[j]] - mesh_P[inner[i+1]]);
 
 			/* use smallest diagonal */
 			if(len1 < len2)
diff --git a/intern/cycles/subd/subd_split.cpp b/intern/cycles/subd/subd_split.cpp
index cca64822647..074c82a2348 100644
--- a/intern/cycles/subd/subd_split.cpp
+++ b/intern/cycles/subd/subd_split.cpp
@@ -74,7 +74,7 @@ int DiagSplit::T(Patch *patch, float2 Pstart, float2 Pend)
 		float3 P = project(patch, Pstart + t*(Pend - Pstart));
 
 		if(i > 0) {
-			float L = length(P - Plast);
+			float L = len(P - Plast);
 			Lsum += L;
 			Lmax = max(L, Lmax);
 		}
diff --git a/intern/cycles/util/util_math.h b/intern/cycles/util/util_math.h
index b7133582696..6fe1b2bcf54 100644
--- a/intern/cycles/util/util_math.h
+++ b/intern/cycles/util/util_math.h
@@ -296,19 +296,19 @@ __device_inline bool operator==(const int2 a, const int2 b)
 	return (a.x == b.x && a.y == b.y);
 }
 
-__device_inline float length(const float2 a)
+__device_inline float len(const float2 a)
 {
 	return sqrtf(dot(a, a));
 }
 
 __device_inline float2 normalize(const float2 a)
 {
-	return a/length(a);
+	return a/len(a);
 }
 
-__device_inline float2 normalize_length(const float2 a, float *t)
+__device_inline float2 normalize_len(const float2 a, float *t)
 {
-	*t = length(a);
+	*t = len(a);
 	return a/(*t);
 }
 
@@ -454,13 +454,14 @@ __device_inline float3 cross(const float3 a, const float3 b)
 	return r;
 }
 
-__device_inline float length(const float3 a)
+#endif
+
+__device_inline float len(const float3 a)
 {
 	return sqrtf(dot(a, a));
 }
-#endif
 
-__device_inline float length_squared(const float3 a)
+__device_inline float len_squared(const float3 a)
 {
 	return dot(a, a);
 }
@@ -469,14 +470,14 @@ __device_inline float length_squared(const float3 a)
 
 __device_inline float3 normalize(const float3 a)
 {
-	return a/length(a);
+	return a/len(a);
 }
 
 #endif
 
-__device_inline float3 normalize_length(const float3 a, float *t)
+__device_inline float3 normalize_len(const float3 a, float *t)
 {
-	*t = length(a);
+	*t = len(a);
 	return a/(*t);
 }
 
@@ -786,14 +787,14 @@ __device_inline float dot(const float4& a, const float4& b)
 	return reduce_add(a * b);
 }
 
-__device_inline float length(const float4 a)
+__device_inline float len(const float4 a)
 {
 	return sqrtf(dot(a, a));
 }
 
 __device_inline float4 normalize(const float4 a)
 {
-	return a/length(a);
+	return a/len(a);
 }
 
 __device_inline float4 min(float4 a, float4 b)
@@ -1049,7 +1050,7 @@ template<class A, class B> A lerp(const A& a, const A& b, const B& t)
 
 __device_inline float triangle_area(const float3 v1, const float3 v2, const float3 v3)
 {
-	return length(cross(v3 - v2, v1 - v2))*0.5f;
+	return len(cross(v3 - v2, v1 - v2))*0.5f;
 }
 
 #endif
@@ -1211,7 +1212,7 @@ __device bool ray_aligned_disk_intersect(
 {
 	/* aligned disk normal */
 	float disk_t;
-	float3 disk_N = normalize_length(ray_P - disk_P, &disk_t);
+	float3 disk_N = normalize_len(ray_P - disk_P, &disk_t);
 	float div = dot(ray_D, disk_N);
 
 	if(div == 0.0f)
@@ -1224,7 +1225,7 @@ __device bool ray_aligned_disk_intersect(
 	
 	/* test if within radius */
 	float3 P = ray_P + ray_D*t;
-	if(length_squared(P - disk_P) > disk_radius*disk_radius)
+	if(len_squared(P - disk_P) > disk_radius*disk_radius)
 		return false;
 
 	*isect_P = P;
diff --git a/intern/cycles/util/util_transform.h b/intern/cycles/util/util_transform.h
index 53e32fcce96..66801e90b56 100644
--- a/intern/cycles/util/util_transform.h
+++ b/intern/cycles/util/util_transform.h
@@ -268,12 +268,12 @@ __device_inline bool transform_uniform_scale(const Transform& tfm, float& scale)
 	Transform ttfm = transform_transpose(tfm);
 	float eps = 1e-6f; 
 	
-	float sx = length_squared(float4_to_float3(tfm.x));
-	float sy = length_squared(float4_to_float3(tfm.y));
-	float sz = length_squared(float4_to_float3(tfm.z));
-	float stx = length_squared(float4_to_float3(ttfm.x));
-	float sty = length_squared(float4_to_float3(ttfm.y));
-	float stz = length_squared(float4_to_float3(ttfm.z));
+	float sx = len_squared(float4_to_float3(tfm.x));
+	float sy = len_squared(float4_to_float3(tfm.y));
+	float sz = len_squared(float4_to_float3(tfm.z));
+	float stx = len_squared(float4_to_float3(ttfm.x));
+	float sty = len_squared(float4_to_float3(ttfm.y));
+	float stz = len_squared(float4_to_float3(ttfm.z));
 
 	if(fabsf(sx - sy) < eps && fabsf(sx - sz) < eps &&
 	   fabsf(sx - stx) < eps && fabsf(sx - sty) < eps &&