diff --git a/src/mol-gl/shader/chunks/wboit-write.glsl.ts b/src/mol-gl/shader/chunks/wboit-write.glsl.ts
index 103eac3d73e4d2866148e04912d1f18628b9f0c6..b2d85796e940c4dd83421adf176d69175601172f 100644
--- a/src/mol-gl/shader/chunks/wboit-write.glsl.ts
+++ b/src/mol-gl/shader/chunks/wboit-write.glsl.ts
@@ -13,7 +13,7 @@ export const wboit_write = `
         }
     } else if (uRenderWboit) {
         // the 'fragmentDepth > 0.99' check is to handle precision issues with packed depth
-        if (preFogAlpha != 1.0 && (!interior || uDoubleSided) && (fragmentDepth < getDepth(gl_FragCoord.xy / uDrawingBufferSize) || fragmentDepth > 0.99)) {
+        if (preFogAlpha != 1.0 && (fragmentDepth < getDepth(gl_FragCoord.xy / uDrawingBufferSize) || fragmentDepth > 0.99)) {
             float alpha = gl_FragColor.a;
             float wboitWeight = alpha * clamp(pow(1.0 - fragmentDepth, 2.0), 0.01, 1.0);
             gl_FragColor = vec4(gl_FragColor.rgb * alpha * wboitWeight, alpha);
diff --git a/src/mol-gl/shader/direct-volume.frag.ts b/src/mol-gl/shader/direct-volume.frag.ts
index b067d6b5e5c706d600f9abbc641ece0754aef3af..02c5ba5a670f3003add96b6032b1cef58b7305e1 100644
--- a/src/mol-gl/shader/direct-volume.frag.ts
+++ b/src/mol-gl/shader/direct-volume.frag.ts
@@ -72,12 +72,7 @@ uniform float uPickingAlphaThreshold;
 uniform bool uTransparentBackground;
 uniform float uXrayEdgeFalloff;
 
-uniform float uInteriorDarkening;
-uniform bool uInteriorColorFlag;
-uniform vec3 uInteriorColor;
-
 uniform bool uRenderWboit;
-uniform bool uDoubleSided;
 
 uniform float uNear;
 uniform float uFar;
@@ -357,7 +352,6 @@ void main() {
 
     float fragmentDepth = calcDepth((uModelView * vec4(start, 1.0)).xyz);
     float preFogAlpha = clamp(preFogAlphaBlended, 0.0, 1.0);
-    bool interior = false;
     #include wboit_write
 }
 `;
\ No newline at end of file
diff --git a/src/mol-gl/shader/image.frag.ts b/src/mol-gl/shader/image.frag.ts
index faab82f86d927c386c2152b1540489c9b24ceeb7..354eb8f8e6a4ec6813b3e5aa1761240f983ccaa6 100644
--- a/src/mol-gl/shader/image.frag.ts
+++ b/src/mol-gl/shader/image.frag.ts
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2020-2021 mol* contributors, licensed under MIT, See LICENSE file for more info.
+ * Copyright (c) 2020-2022 mol* contributors, licensed under MIT, See LICENSE file for more info.
  *
  * @author Alexander Rose <alexander.rose@weirdbyte.de>
  */
@@ -99,7 +99,6 @@ void main() {
     if (imageData.a > 0.9) imageData.a = 1.0;
 
     float fragmentDepth = gl_FragCoord.z;
-    bool interior = false;
 
     #if defined(dRenderVariant_pick)
         if (imageData.a < 0.3)
diff --git a/src/mol-gl/shader/lines.frag.ts b/src/mol-gl/shader/lines.frag.ts
index 1340a5efa621680908e3f9f2587f7f5703427c4a..975509af9269cccf9dd259a535ba4bdfbf37f509 100644
--- a/src/mol-gl/shader/lines.frag.ts
+++ b/src/mol-gl/shader/lines.frag.ts
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2018-2021 mol* contributors, licensed under MIT, See LICENSE file for more info.
+ * Copyright (c) 2018-2022 mol* contributors, licensed under MIT, See LICENSE file for more info.
  *
  * @author Alexander Rose <alexander.rose@weirdbyte.de>
  */
@@ -16,7 +16,6 @@ precision highp int;
 void main(){
     #include clip_pixel
 
-    bool interior = false;
     float fragmentDepth = gl_FragCoord.z;
     #include assign_material_color
 
diff --git a/src/mol-gl/shader/points.frag.ts b/src/mol-gl/shader/points.frag.ts
index 0d52802e2b016c3dcdec83863ab2ce6180eb0448..7d413e57608c19208522df1b3f1261ddfc6fa6da 100644
--- a/src/mol-gl/shader/points.frag.ts
+++ b/src/mol-gl/shader/points.frag.ts
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2018-2021 mol* contributors, licensed under MIT, See LICENSE file for more info.
+ * Copyright (c) 2018-2022 mol* contributors, licensed under MIT, See LICENSE file for more info.
  *
  * @author Alexander Rose <alexander.rose@weirdbyte.de>
  */
@@ -20,7 +20,6 @@ void main(){
     #include clip_pixel
 
     float fragmentDepth = gl_FragCoord.z;
-    bool interior = false;
     #include assign_material_color
 
     #if defined(dPointStyle_circle)
diff --git a/src/mol-gl/shader/text.frag.ts b/src/mol-gl/shader/text.frag.ts
index 390886e55eeed3945290e86b1732727ab04cb960..fd1f1b3b95bfbafb27cd90ab354714e350a0eac7 100644
--- a/src/mol-gl/shader/text.frag.ts
+++ b/src/mol-gl/shader/text.frag.ts
@@ -1,5 +1,5 @@
 /**
- * Copyright (c) 2019-2021 mol* contributors, licensed under MIT, See LICENSE file for more info.
+ * Copyright (c) 2019-2022 mol* contributors, licensed under MIT, See LICENSE file for more info.
  *
  * @author Alexander Rose <alexander.rose@weirdbyte.de>
  */
@@ -33,7 +33,6 @@ void main(){
     #include clip_pixel
 
     float fragmentDepth = gl_FragCoord.z;
-    bool interior = false;
     #include assign_material_color
 
     if (vTexCoord.x > 1.0) {