From e3f1d980982b1c0da7853a960cbd3e9a3f434376 Mon Sep 17 00:00:00 2001
From: Matt Heimlich <m9105826>
Date: Wed, 28 Mar 2018 23:18:46 +0200
Subject: Cycles: take into account diffuse roughness for roughness baking.

Roughness baking previously defaulted to 1.0 for all diffuse materials,
now we also bake roughness values of Oren-Nayer and Principled Diffuse.

Differential Revision: https://developer.blender.org/D3115
---
 intern/cycles/kernel/closure/bsdf.h  | 28 +++++++++++++++++++++++++---
 intern/cycles/kernel/kernel_passes.h |  2 +-
 2 files changed, 26 insertions(+), 4 deletions(-)

(limited to 'intern/cycles/kernel')

diff --git a/intern/cycles/kernel/closure/bsdf.h b/intern/cycles/kernel/closure/bsdf.h
index e3beff6675a..d8ff69ca241 100644
--- a/intern/cycles/kernel/closure/bsdf.h
+++ b/intern/cycles/kernel/closure/bsdf.h
@@ -36,20 +36,42 @@ CCL_NAMESPACE_BEGIN
 
 /* Returns the square of the roughness of the closure if it has roughness,
  * 0 for singular closures and 1 otherwise. */
-ccl_device_inline float bsdf_get_roughness_squared(const ShaderClosure *sc)
+ccl_device_inline float bsdf_get_specular_roughness_squared(const ShaderClosure *sc)
 {
 	if(CLOSURE_IS_BSDF_SINGULAR(sc->type)) {
 		return 0.0f;
 	}
 
 	if(CLOSURE_IS_BSDF_MICROFACET(sc->type)) {
-		MicrofacetBsdf *bsdf = (MicrofacetBsdf*) sc;
+		MicrofacetBsdf *bsdf = (MicrofacetBsdf*)sc;
 		return bsdf->alpha_x*bsdf->alpha_y;
 	}
 
 	return 1.0f;
 }
 
+ccl_device_inline float bsdf_get_roughness_squared(const ShaderClosure *sc)
+{
+	/* This version includes diffuse, mainly for baking Principled BSDF
+	 * where specular and metallic zero otherwise does not bake the
+	 * specified roughness parameter. */
+	if(sc->type == CLOSURE_BSDF_OREN_NAYAR_ID) {
+		OrenNayarBsdf *bsdf = (OrenNayarBsdf*)sc;
+		return sqr(sqr(bsdf->roughness));
+	}
+
+	if(sc->type == CLOSURE_BSDF_PRINCIPLED_DIFFUSE_ID) {
+		PrincipledDiffuseBsdf *bsdf = (PrincipledDiffuseBsdf*)sc;
+		return sqr(sqr(bsdf->roughness));
+	}
+
+	if(CLOSURE_IS_BSDF_DIFFUSE(sc->type)) {
+		return 0.0f;
+	}
+
+	return bsdf_get_specular_roughness_squared(sc);
+}
+
 ccl_device_forceinline int bsdf_sample(KernelGlobals *kg,
                                        ShaderData *sd,
                                        const ShaderClosure *sc,
@@ -176,7 +198,7 @@ ccl_device_forceinline int bsdf_sample(KernelGlobals *kg,
 		float threshold_squared = kernel_data.background.transparent_roughness_squared_threshold;
 
 		if(threshold_squared >= 0.0f) {
-			if(bsdf_get_roughness_squared(sc) <= threshold_squared) {
+			if(bsdf_get_specular_roughness_squared(sc) <= threshold_squared) {
 				label |= LABEL_TRANSMIT_TRANSPARENT;
 			}
 		}
diff --git a/intern/cycles/kernel/kernel_passes.h b/intern/cycles/kernel/kernel_passes.h
index 1933d695f92..a42a8e9812f 100644
--- a/intern/cycles/kernel/kernel_passes.h
+++ b/intern/cycles/kernel/kernel_passes.h
@@ -140,7 +140,7 @@ ccl_device_inline void kernel_update_denoising_features(KernelGlobals *kg,
 		/* All closures contribute to the normal feature, but only diffuse-like ones to the albedo. */
 		normal += sc->N * sc->sample_weight;
 		sum_weight += sc->sample_weight;
-		if(bsdf_get_roughness_squared(sc) > sqr(0.075f)) {
+		if(bsdf_get_specular_roughness_squared(sc) > sqr(0.075f)) {
 			albedo += sc->weight;
 			sum_nonspecular_weight += sc->sample_weight;
 		}
-- 
cgit v1.2.3