fix yining masking term

keptsecret · keptsecret · commit 6e84d79a6bce · 2026-04-29T14:53:33.000+07:00
diff --git a/include/nbl/builtin/hlsl/bxdf/ndf/microfacet_normal_shadowing.hlsl b/include/nbl/builtin/hlsl/bxdf/ndf/microfacet_normal_shadowing.hlsl
@@ -64,7 +64,7 @@ struct ShadowingMethod<T, PNS_YINING>
     static scalar_type G1(const scalar_type clampedNdotL, const scalar_type NdotNp, const scalar_type clampedNpdotL, const scalar_type clampedNtdotL)
     {
         const scalar_type g = hlsl::min(scalar_type(1.0),
-            clampedNpdotL / (clampedNdotL * NdotNp)
+            clampedNdotL / (clampedNpdotL * NdotNp)
         );
         const scalar_type g2 = g * g;
         return -g2 * g + g2 + g;
@@ -80,6 +80,8 @@ struct ShadowingMethod<T, PNS_YINING>
     {
         const scalar_type sinThetaNp = hlsl::sqrt(hlsl::max(1.0 - NdotNp * NdotNp, 0.0));
         const scalar_type ap = clampedNpdotV * NdotNp;
+        if (ap < numeric_limits<scalar_type>::min)
+            return scalar_type(0.0);
         const scalar_type at = clampedNtdotV * sinThetaNp;
         return ap / (ap + at);
     }

Original file line number	Diff line number	Diff line change
`@@ -64,7 +64,7 @@ struct ShadowingMethod<T, PNS_YINING>`
`64`	`64`	`static scalar_type G1(const scalar_type clampedNdotL, const scalar_type NdotNp, const scalar_type clampedNpdotL, const scalar_type clampedNtdotL)`
`65`	`65`	`{`
`66`	`66`	`const scalar_type g = hlsl::min(scalar_type(1.0),`
`67`		`- clampedNpdotL / (clampedNdotL * NdotNp)`
	`67`	`+ clampedNdotL / (clampedNpdotL * NdotNp)`
`68`	`68`	`);`
`69`	`69`	`const scalar_type g2 = g * g;`
`70`	`70`	`return -g2 * g + g2 + g;`
`@@ -80,6 +80,8 @@ struct ShadowingMethod<T, PNS_YINING>`
`80`	`80`	`{`
`81`	`81`	`const scalar_type sinThetaNp = hlsl::sqrt(hlsl::max(1.0 - NdotNp * NdotNp, 0.0));`
`82`	`82`	`const scalar_type ap = clampedNpdotV * NdotNp;`
	`83`	`+ if (ap < numeric_limits<scalar_type>::min)`
	`84`	`+ return scalar_type(0.0);`
`83`	`85`	`const scalar_type at = clampedNtdotV * sinThetaNp;`
`84`	`86`	`return ap / (ap + at);`
`85`	`87`	`}`