Merge pull request #1882 from secondlife/v-1847

secondlife/viewer#1847: Fix negative UV scale inverting normal texture lighting for PBR materials and PBR terrain

1 files changed, 4 insertions, 3 deletions

diff --git a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
index ae179d3f37..66adf50fa9 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/pbralphaV.glsl
@@ -69,7 +69,7 @@ flat out float vary_sign;
 out vec3 vary_normal;
 
 vec2 texture_transform(vec2 vertex_texcoord, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
-vec3 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
+vec4 tangent_space_transform(vec4 vertex_tangent, vec3 vertex_normal, vec4[2] khr_gltf_transform, mat4 sl_animation_transform);
 
 
 void main()
@@ -103,8 +103,9 @@ void main()
 
     n = normalize(n);
 
-    vary_tangent = normalize(tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0));
-    vary_sign = tangent.w;
+    vec4 transformed_tangent = tangent_space_transform(vec4(t, tangent.w), n, texture_normal_transform, texture_matrix0);
+    vary_tangent = normalize(transformed_tangent.xyz);
+    vary_sign = transformed_tangent.w;
     vary_normal = n;
 
     vertex_color = diffuse_color;