Cycles:

* Sun, area and point lights with size now supported
* Cast shadow option to disable shadow casting for lamps
* Emission strength of materials tweaked such that setting strength to 1.0
  basically makes the material "shadeless" in that the value of the color
  input will be the resulting color in the image.

4 files changed, 13 insertions, 16 deletions

diff --git a/intern/cycles/kernel/kernel_emission.h b/intern/cycles/kernel/kernel_emission.h
index 13c48464088..22970f66669 100644
--- a/intern/cycles/kernel/kernel_emission.h
+++ b/intern/cycles/kernel/kernel_emission.h
@@ -88,14 +88,11 @@ __device bool direct_emission(KernelGlobals *kg, ShaderData *sd, int lindex,
 		float mis_weight = power_heuristic(pdf, bsdf_pdf);
 		*eval *= mis_weight;
 	}
-	else if(!(ls.shader & SHADER_AREA_LIGHT)) {
-		/* ensure point light works in Watts, this should be handled
-		 * elsewhere but for now together with the diffuse emission
-		 * closure it works out to the right value */
-		*eval *= 0.25f;
-
-		/* XXX verify with other light types */
-	}
+	/* todo: clean up these weights */
+	else if(ls.shader & SHADER_AREA_LIGHT)
+		*eval *= 0.25f; /* area lamp */
+	else if(ls.t != FLT_MAX)
+		*eval *= 0.25f*M_1_PI_F; /* point lamp */
 
 	if(ls.shader & SHADER_CAST_SHADOW) {
 		/* setup ray */
diff --git a/intern/cycles/kernel/kernel_light.h b/intern/cycles/kernel/kernel_light.h
index 68d08a2655f..d5d47b28d59 100644
--- a/intern/cycles/kernel/kernel_light.h
+++ b/intern/cycles/kernel/kernel_light.h
@@ -75,8 +75,8 @@ __device void regular_light_sample(KernelGlobals *kg, int point,
 			D = distant_light_sample(D, size, randu, randv);
 
 		ls->P = D;
-		ls->Ng = -D;
-		ls->D = D;
+		ls->Ng = D;
+		ls->D = -D;
 		ls->t = FLT_MAX;
 	}
 	else {
@@ -120,9 +120,9 @@ __device float regular_light_pdf(KernelGlobals *kg,
 	if(t == FLT_MAX)
 		return pdf;
 
-	float cos_pi = fabsf(dot(Ng, I));
+	float cos_pi = dot(Ng, I);
 
-	if(cos_pi == 0.0f)
+	if(cos_pi <= 0.0f)
 		return 0.0f;
 
 	return t*t*pdf/cos_pi;
diff --git a/intern/cycles/kernel/osl/emissive.cpp b/intern/cycles/kernel/osl/emissive.cpp
index 28d3c73e59b..2d2d6e1fdde 100644
--- a/intern/cycles/kernel/osl/emissive.cpp
+++ b/intern/cycles/kernel/osl/emissive.cpp
@@ -64,7 +64,7 @@ public:
     Color3 eval (const Vec3 &Ng, const Vec3 &omega_out) const
     {
         float cosNO = fabsf(Ng.dot(omega_out));
-        float res = cosNO > 0 ? 1.0f / float(M_PI) : 0.0f;
+        float res = cosNO > 0 ? 1.0f: 0.0f;
         return Color3(res, res, res);
     }
 
@@ -91,7 +91,7 @@ public:
                const Vec3 &omega_out) const
     {
         float cosNO = Ng.dot(omega_out);
-        return cosNO > 0 ? 1.0f / float(M_PI) : 0.0f;
+        return cosNO > 0 ? 1.0f: 0.0f;
     }
 };
 
diff --git a/intern/cycles/kernel/svm/emissive.h b/intern/cycles/kernel/svm/emissive.h
index 8bd31751fb3..e3f99e9b729 100644
--- a/intern/cycles/kernel/svm/emissive.h
+++ b/intern/cycles/kernel/svm/emissive.h
@@ -37,7 +37,7 @@ CCL_NAMESPACE_BEGIN
 __device float3 emissive_eval(const float3 Ng, const float3 I)
 {
 	float cosNO = fabsf(dot(Ng, I));
-	float res = (cosNO > 0.0f)? M_1_PI_F: 0.0f;
+	float res = (cosNO > 0.0f)? 1.0f: 0.0f;
 	
 	return make_float3(res, res, res);
 }
@@ -48,7 +48,7 @@ __device float3 emissive_eval(const float3 Ng, const float3 I)
 __device float emissive_pdf(const float3 Ng, const float3 I)
 {
 	float cosNO = fabsf(dot(Ng, I));
-	return (cosNO > 0.0f)? M_1_PI_F: 0.0f;
+	return (cosNO > 0.0f)? 1.0f: 0.0f;
 }
 
 __device float3 svm_emissive_eval(ShaderData *sd, ShaderClosure *sc)