Some small modifications.

Absorption and Dispersion parameters now only visible when 'Ray Transp'
enabled. WardIso specular amount scale to match Blender output.
Updated halo spotlight 'samples' to use new yafray syntax.

Quick addition for access to another yafray feature:
When using HDR backgrounds for lighting ('SkyDome' of 'Full' GI methods),
it is currently not always possible to get smooth lighting results.
Especially HDR images with small lightsource can be very noisy,
because currently yafray still relies on brute force random sampling.
As a temporary simple solution (better options will be available in the
'next generation' yafray), yafray can do some processing on the
image to smooth out all (or most) noise.
Besides smooth lighting, this also has
the advantage that AA will have less work to do,
GI quality can be set to the lowest level and still get reasonably
good results. Disadvantage however is that shadow definition is lost.
To switch on this option, set the world image texture filter parameter
to any value greater than 1.0
When 'filter' is 1.0 or less, normal hdr sampling is done as before.

So, current fastest possible render settings for IBL:
set texture image filter parameter of the background image to any value
greater than 1.0, set GI to 'SkyDome' type, enable 'Cache',
(possibly enable 'NoBump' when scene uses lots of bumpmapping),
set 'Quality' menu to 'Use Blender AO settings',
make sure AO is enabled in blender World buttons and set there the number
of AO samples to 1.
Should at least be good enough for previews.

4 files changed, 43 insertions, 19 deletions

diff --git a/source/blender/src/buttons_shading.c b/source/blender/src/buttons_shading.c
index 29c79ec0d30..f5d0d64d0e5 100644
--- a/source/blender/src/buttons_shading.c
+++ b/source/blender/src/buttons_shading.c
@@ -2922,22 +2922,26 @@ static void material_panel_tramir_yafray(Material *ma)
 
 	/* ior has extended range up to 30, for use with total fresnel reflection */
 	uiDefButF(block, NUMSLI, B_MATPRV, "IOR ", 10,115,150,20, &(ma->ang), 1.0, 30.0, 100, 2, "Sets the angular index of refraction for raytrace");
-	if(ma->mode & MA_RAYTRANSP)
+
+	// parameters only used in ray_transp mode
+	if(ma->mode & MA_RAYTRANSP) {
+		// Filter
 		uiDefButF(block, NUM, B_MATPRV, "Filt:", 160,115,150,20, &(ma->filter), 0.0, 1.0, 10, 0, "Amount of filtering for transparent raytrace");
 
-	/* absorption color */
-	uiDefBut(block, LABEL, 0, "Absorption Color", 10, 98, 150, 18, 0, 0.0, 0.0, 0, 0, "");
-	uiDefButF(block, COL, B_MATPRV_DRAW, "", 10, 38, 30, 58, &ma->YF_ar, 0, 0, 0, B_MATCOL, "transmit absorption color, white is no absorption");
-	uiDefButF(block, NUMSLI, B_MATPRV, "aR ", 40, 78, 120, 18, &ma->YF_ar, 1e-7f, 1.0, B_MATCOL, 0, "");
-	uiDefButF(block, NUMSLI, B_MATPRV, "aG ", 40, 58, 120, 18, &ma->YF_ag, 1e-7f, 1.0, B_MATCOL, 0, "");
-	uiDefButF(block, NUMSLI, B_MATPRV, "aB ", 40, 38, 120, 18, &ma->YF_ab, 1e-7f, 1.0, B_MATCOL, 0, "");
-	uiDefButF(block, NUM, B_MATPRV, "Ds", 10, 18, 150, 18, &ma->YF_dscale, 1e-7f, 100.0, 10.0, 0, "absorption distance scale, 1 is one blender (world) unit of distance");
-
-	/* disperions parameters */
-	uiDefBut(block, LABEL, 0, "Dispersion", 160, 98, 150, 18, 0, 0.0, 0.0, 0, 0, "");
-	uiDefButF(block, NUM, B_MATPRV, "Pwr ", 160, 78, 150, 18, &ma->YF_dpwr, 0.0, 1.0, 0.25, 0, "Dispersion power, the higher, the more dispersion, 0 is no dispersion");
-	uiDefButI(block, NUM, B_MATPRV, "Samples ", 160, 58, 150, 18, &ma->YF_dsmp, 1.0, 100.0, 0, 0, "Dispersion samples, minimum at least 10, unless using jitter ");
-	uiDefButI(block, TOG|BIT|0, B_MATPRV, "Jitter", 160, 38, 150, 18, &ma->YF_djit, 0.0, 1.0, 0, 0, "Enable jittering of wavelenghts, adds noise");
+		/* absorption color */
+		uiDefBut(block, LABEL, 0, "Absorption Color", 10, 98, 150, 18, 0, 0.0, 0.0, 0, 0, "");
+		uiDefButF(block, COL, B_MATPRV_DRAW, "", 10, 38, 30, 58, &ma->YF_ar, 0, 0, 0, B_MATCOL, "transmit absorption color, white is no absorption");
+		uiDefButF(block, NUMSLI, B_MATPRV, "aR ", 40, 78, 120, 18, &ma->YF_ar, 1e-7f, 1.0, B_MATCOL, 0, "");
+		uiDefButF(block, NUMSLI, B_MATPRV, "aG ", 40, 58, 120, 18, &ma->YF_ag, 1e-7f, 1.0, B_MATCOL, 0, "");
+		uiDefButF(block, NUMSLI, B_MATPRV, "aB ", 40, 38, 120, 18, &ma->YF_ab, 1e-7f, 1.0, B_MATCOL, 0, "");
+		uiDefButF(block, NUM, B_MATPRV, "Ds", 10, 18, 150, 18, &ma->YF_dscale, 1e-7f, 100.0, 10.0, 0, "absorption distance scale, 1 is one blender (world) unit of distance");
+
+		/* disperions parameters */
+		uiDefBut(block, LABEL, 0, "Dispersion", 160, 98, 150, 18, 0, 0.0, 0.0, 0, 0, "");
+		uiDefButF(block, NUM, B_MATPRV, "Pwr ", 160, 78, 150, 18, &ma->YF_dpwr, 0.0, 1.0, 0.25, 0, "Dispersion power, the higher, the more dispersion, 0 is no dispersion");
+		uiDefButI(block, NUM, B_MATPRV, "Samples ", 160, 58, 150, 18, &ma->YF_dsmp, 1.0, 100.0, 0, 0, "Dispersion samples, minimum at least 10, unless using jitter ");
+		uiDefButI(block, TOG|BIT|0, B_MATPRV, "Jitter", 160, 38, 150, 18, &ma->YF_djit, 0.0, 1.0, 0, 0, "Enable jittering of wavelenghts, adds noise");
+	}
 
 }
 
diff --git a/source/blender/yafray/intern/export_File.cpp b/source/blender/yafray/intern/export_File.cpp
index d35903ba91d..43128b35933 100755
--- a/source/blender/yafray/intern/export_File.cpp
+++ b/source/blender/yafray/intern/export_File.cpp
@@ -667,7 +667,14 @@ void yafrayFileRender_t::writeShader(const string &shader_name, Material* matr,
 	ostr << "<shader type=\"blendershader\" name=\"" << shader_name << "\" >\n";
 	ostr << "\t<attributes>\n";
 	ostr << "\t\t<color r=\"" << matr->r << "\" g=\"" << matr->g << "\" b=\"" << matr->b << "\" />\n";
-	ostr << "\t\t<specular_color r=\"" << matr->specr << "\" g=\"" << matr->specg << "\" b=\"" << matr->specb << "\" />\n";
+	float sr=matr->specr, sg=matr->specg, sb=matr->specb;
+	if (matr->spec_shader==MA_SPEC_WARDISO) {
+		// ........
+		sr /= M_PI;
+		sg /= M_PI;
+		sb /= M_PI;
+	}
+	ostr << "\t\t<specular_color r=\"" << sr << "\" g=\"" << sg << "\" b=\"" << sb << "\" />\n";
 	ostr << "\t\t<mirror_color r=\"" << matr->mirr << "\" g=\"" << matr->mirg << "\" b=\"" << matr->mirb << "\" />\n";
 	ostr << "\t\t<diffuse_reflect value=\"" << matr->ref << "\" />\n";
 	ostr << "\t\t<specular_amount value=\"" << matr->spec << "\" />\n";
@@ -1615,7 +1622,9 @@ void yafrayFileRender_t::writeLamps()
 				ostr << "\n\thalo=\"on\" " << "res=\"" << lamp->YF_bufsize << "\"\n";
 				int hsmp = ((12-lamp->shadhalostep)*16)/12;
 				hsmp = (hsmp+1)*16;	// makes range (16, 272) for halostep(12, 0), good enough?
-				ostr << "\tsamples=\"" << hsmp <<  "\" shadow_samples=\"" << (lamp->samp*lamp->samp) << "\"\n";
+				// halo 'samples' now 'stepsize'
+				// convert from old integer samples value to some reasonable stepsize
+				ostr << "\tstepsize=\"" << (1.0/sqrt((float)hsmp)) <<  "\" shadow_samples=\"" << (lamp->samp*lamp->samp) << "\"\n";
 				ostr << "\thalo_blur=\"0\" shadow_blur=\"" << (lamp->soft*0.01f) << "\"\n";
 				ostr << "\tfog_density=\"" << (lamp->haint*0.2f) << "\"";
 			}
@@ -1886,6 +1895,7 @@ bool yafrayFileRender_t::writeWorld()
 				ostr << " mapping=\"tube\" >\n";
 			ostr << "\t<filename value=\"" << wt_path << "\" />\n";
 			ostr << "\t<interpolate value=\"" << ((wtex->tex->imaflag & TEX_INTERPOL) ? "bilinear" : "none") << "\" />\n";
+			if (wtex->tex->filtersize>1.f) ostr << "\t<prefilter value=\"on\" />\n";
 			ostr << "</background>\n\n";
 			xmlfile << ostr.str();
 			return true;
diff --git a/source/blender/yafray/intern/export_Plugin.cpp b/source/blender/yafray/intern/export_Plugin.cpp
index 0dad8f9de36..27333c89b89 100644
--- a/source/blender/yafray/intern/export_Plugin.cpp
+++ b/source/blender/yafray/intern/export_Plugin.cpp
@@ -653,7 +653,14 @@ void yafrayPluginRender_t::writeShader(const string &shader_name, Material* matr
 	params["type"] = yafray::parameter_t("blendershader");
 	params["name"] = yafray::parameter_t(shader_name);
 	params["color"] = yafray::parameter_t(yafray::color_t(matr->r, matr->g, matr->b));
-	params["specular_color"] = yafray::parameter_t(yafray::color_t(matr->specr, matr->specg, matr->specb));
+	float sr=matr->specr, sg=matr->specg, sb=matr->specb;
+	if (matr->spec_shader==MA_SPEC_WARDISO) {
+		// ........
+		sr /= M_PI;
+		sg /= M_PI;
+		sb /= M_PI;
+	}
+	params["specular_color"] = yafray::parameter_t(yafray::color_t(sr, sg, sb));
 	params["mirror_color"] = yafray::parameter_t(yafray::color_t(matr->mirr, matr->mirg, matr->mirb));
 	params["diffuse_reflect"] = yafray::parameter_t(matr->ref);
 	params["specular_amount"] = yafray::parameter_t(matr->spec);
@@ -1593,7 +1600,9 @@ void yafrayPluginRender_t::writeLamps()
 				params["res"] = yafray::parameter_t(lamp->YF_bufsize);
 				int hsmp = ((12-lamp->shadhalostep)*16)/12;
 				hsmp = (hsmp+1)*16;	// makes range (16, 272) for halostep(12, 0), good enough?
-				params["samples"] = yafray::parameter_t(hsmp);
+				// halo 'samples' now 'stepsize'
+				// convert from old integer samples value to some reasonable stepsize
+				params["stepsize"] = yafray::parameter_t(1.0/sqrt((float)hsmp));
 				params["shadow_samples"] = yafray::parameter_t(lamp->samp*lamp->samp);
 				params["halo_blur"] = yafray::parameter_t(0.0);
 				params["shadow_blur"] = yafray::parameter_t(lamp->soft*0.01f);
@@ -1879,6 +1888,7 @@ bool yafrayPluginRender_t::writeWorld()
 				params["mapping"] = yafray::parameter_t("tube");
 			params["filename"] = yafray::parameter_t(wt_path);
 			params["interpolate"] = yafray::parameter_t((wtex->tex->imaflag & TEX_INTERPOL) ? "bilinear" : "none");
+			if (wtex->tex->filtersize>1.f) params["prefilter"] = yafray::parameter_t("on");
 			yafrayGate->addBackground(params);
 			return true;
 		}
diff --git a/source/blender/yafray/intern/export_Plugin.h b/source/blender/yafray/intern/export_Plugin.h
index c1d6a7fbd2e..2ec79ba1625 100644
--- a/source/blender/yafray/intern/export_Plugin.h
+++ b/source/blender/yafray/intern/export_Plugin.h
@@ -35,7 +35,7 @@ class yafrayPluginRender_t : public yafrayRender_t
 		virtual void writeTextures();
 		virtual void writeShader(const std::string &shader_name, Material* matr, const std::string &facetexname="");
 		virtual void writeMaterialsAndModulators();
-		virtual void writeObject(Object* obj, 
+		virtual void writeObject(Object* obj,
 				const std::vector<VlakRen*> &VLR_list, const float obmat[4][4]);
 		virtual void writeAllObjects();
 		virtual void writeAreaLamp(LampRen* lamp, int num, float iview[4][4]);