Cycles: spot lamp support.

4 files changed, 45 insertions, 15 deletions

diff --git a/intern/cycles/kernel/kernel_emission.h b/intern/cycles/kernel/kernel_emission.h
index 0ef1425e68a..881d25ad7ba 100644
--- a/intern/cycles/kernel/kernel_emission.h
+++ b/intern/cycles/kernel/kernel_emission.h
@@ -104,13 +104,8 @@ __device bool direct_emission(KernelGlobals *kg, ShaderData *sd, int lindex,
 		float mis_weight = power_heuristic(pdf, bsdf_pdf);
 		light_eval *= mis_weight;
 	}
-	/* todo: clean up these weights */
-	else if(ls.shader & SHADER_AREA_LIGHT)
-		light_eval *= 0.25f; /* area lamp */
-	else if(ls.t != FLT_MAX)
-		light_eval *= 0.25f*M_1_PI_F; /* point lamp */
 	
-	bsdf_eval_mul(eval, light_eval/pdf);
+	bsdf_eval_mul(eval, light_eval*(ls.eval_fac/pdf));
 
 	if(bsdf_eval_is_zero(eval))
 		return false;
diff --git a/intern/cycles/kernel/kernel_light.h b/intern/cycles/kernel/kernel_light.h
index e9e7fbd4ca1..76552400f9c 100644
--- a/intern/cycles/kernel/kernel_light.h
+++ b/intern/cycles/kernel/kernel_light.h
@@ -23,6 +23,7 @@ typedef struct LightSample {
 	float3 D;
 	float3 Ng;
 	float t;
+	float eval_fac;
 	int object;
 	int prim;
 	int shader;
@@ -189,6 +190,7 @@ __device void regular_light_sample(KernelGlobals *kg, int point,
 		ls->Ng = D;
 		ls->D = -D;
 		ls->t = FLT_MAX;
+		ls->eval_fac = 1.0f;
 	}
 #ifdef __BACKGROUND_MIS__
 	else if(type == LIGHT_BACKGROUND) {
@@ -199,6 +201,7 @@ __device void regular_light_sample(KernelGlobals *kg, int point,
 		ls->Ng = D;
 		ls->D = -D;
 		ls->t = FLT_MAX;
+		ls->eval_fac = 1.0f;
 	}
 #endif
 	else {
@@ -212,6 +215,36 @@ __device void regular_light_sample(KernelGlobals *kg, int point,
 				ls->P += sphere_light_sample(P, ls->P, size, randu, randv);
 
 			ls->Ng = normalize(P - ls->P);
+			ls->eval_fac = 0.25f*M_1_PI_F;
+		}
+		else if(type == LIGHT_SPOT) {
+			float4 data2 = kernel_tex_fetch(__light_data, point*LIGHT_SIZE + 2);
+			float size = data1.y;
+
+			/* spot light */
+			if(size > 0.0f)
+				ls->P += sphere_light_sample(P, ls->P, size, randu, randv);
+
+			float3 dir = make_float3(data1.z, data1.w, data2.x);
+			float3 I = normalize(P - ls->P);
+
+			float spot_angle = data2.y;
+			float spot_smooth = data2.z;
+
+			float eval_fac = fabsf(dot(dir, I));
+
+			if(eval_fac <= spot_angle) {
+				eval_fac = 0.0f;
+			}
+			else {
+				float t = eval_fac - spot_angle;
+
+				if(t < spot_smooth && spot_smooth != 0.0f)
+					eval_fac *= smoothstepf(t/spot_smooth);
+			}
+
+			ls->Ng = I;
+			ls->eval_fac = eval_fac*0.25f*M_1_PI_F;
 		}
 		else {
 			/* area light */
@@ -224,6 +257,7 @@ __device void regular_light_sample(KernelGlobals *kg, int point,
 
 			ls->P += area_light_sample(axisu, axisv, randu, randv);
 			ls->Ng = D;
+			ls->eval_fac = 0.25f;
 		}
 
 		ls->t = 0.0f;
@@ -262,6 +296,7 @@ __device void triangle_light_sample(KernelGlobals *kg, int prim, int object,
 	ls->prim = prim;
 	ls->t = 0.0f;
 	ls->type = LIGHT_AREA;
+	ls->eval_fac = 1.0f;
 
 #ifdef __INSTANCING__
 	/* instance transform */
diff --git a/intern/cycles/kernel/kernel_types.h b/intern/cycles/kernel/kernel_types.h
index a64c850d35a..d119057ac67 100644
--- a/intern/cycles/kernel/kernel_types.h
+++ b/intern/cycles/kernel/kernel_types.h
@@ -283,7 +283,8 @@ typedef enum LightType {
 	LIGHT_DISTANT,
 	LIGHT_BACKGROUND,
 	LIGHT_AREA,
-	LIGHT_AO
+	LIGHT_AO,
+	LIGHT_SPOT
 } LightType;
 
 /* Camera Type */
diff --git a/intern/cycles/kernel/svm/emissive.h b/intern/cycles/kernel/svm/emissive.h
index e3f99e9b729..0b0218674b8 100644
--- a/intern/cycles/kernel/svm/emissive.h
+++ b/intern/cycles/kernel/svm/emissive.h
@@ -34,14 +34,6 @@ CCL_NAMESPACE_BEGIN
 
 /* EMISSION CLOSURE */
 
-__device float3 emissive_eval(const float3 Ng, const float3 I)
-{
-	float cosNO = fabsf(dot(Ng, I));
-	float res = (cosNO > 0.0f)? 1.0f: 0.0f;
-	
-	return make_float3(res, res, res);
-}
-
 /// Return the probability distribution function in the direction I,
 /// given the parameters and the light's surface normal.  This MUST match
 /// the PDF computed by sample().
@@ -51,6 +43,13 @@ __device float emissive_pdf(const float3 Ng, const float3 I)
 	return (cosNO > 0.0f)? 1.0f: 0.0f;
 }
 
+__device float3 emissive_eval(const float3 Ng, const float3 I)
+{
+	float res = emissive_pdf(Ng, I);
+	
+	return make_float3(res, res, res);
+}
+
 __device float3 svm_emissive_eval(ShaderData *sd, ShaderClosure *sc)
 {
 	return emissive_eval(sd->Ng, sd->I);