fix wrong get refraction eta in iridescent transmission

keptsecret · keptsecret · commit 76ed66ca21da · 2025-12-05T16:34:58.000+07:00
diff --git a/include/nbl/builtin/hlsl/bxdf/fresnel.hlsl b/include/nbl/builtin/hlsl/bxdf/fresnel.hlsl
@@ -752,7 +752,7 @@ struct Iridescent<T, true, Colorspace NBL_PARTIAL_REQ_BOT(concepts::FloatingPoin
                                                             base_type::eta12, base_type::eta23, getEtak23(), clampedCosTheta);
     }
 
-    scalar_type getRefractionOrientedEta() NBL_CONST_MEMBER_FUNC { return base_type::ior1[0] / base_type::ior3[0]; }
+    scalar_type getRefractionOrientedEta() NBL_CONST_MEMBER_FUNC { return base_type::ior3[0] / base_type::ior1[0]; }
     OrientedEtaRcps<eta_type> getOrientedEtaRcps() NBL_CONST_MEMBER_FUNC
     {
         OrientedEtaRcps<eta_type> rcpEta;

Original file line number	Diff line number	Diff line change
`@@ -752,7 +752,7 @@ struct Iridescent<T, true, Colorspace NBL_PARTIAL_REQ_BOT(concepts::FloatingPoin`
`752`	`752`	`base_type::eta12, base_type::eta23, getEtak23(), clampedCosTheta);`
`753`	`753`	`}`
`754`	`754`
`755`		`- scalar_type getRefractionOrientedEta() NBL_CONST_MEMBER_FUNC { return base_type::ior1[0] / base_type::ior3[0]; }`
	`755`	`+ scalar_type getRefractionOrientedEta() NBL_CONST_MEMBER_FUNC { return base_type::ior3[0] / base_type::ior1[0]; }`
`756`	`756`	`OrientedEtaRcps<eta_type> getOrientedEtaRcps() NBL_CONST_MEMBER_FUNC`
`757`	`757`	`{`
`758`	`758`	`OrientedEtaRcps<eta_type> rcpEta;`