volume render tweaks

src/mol-gl/shader/direct-volume.frag

@@ -144,6 +144,6 @@ void main () {
     gl_FragColor = raymarch(startLoc, step, normalize(cameraPos));
     if (length(gl_FragColor.rgb) < 0.00001) discard;
     #if defined(dRenderMode_volume)
-        gl_FragColor.a = uAlpha;
+        gl_FragColor.a *= uAlpha;
     #endif
 }

src/mol-math/geometry/gaussian-density/gpu.ts

@@ -226,7 +226,6 @@ async function prepareGaussianDensityData(ctx: RuntimeContext, position: Positio
         }
     }
 
-
     const pad = maxRadius * 2 + resolution
     const expandedBox = Box3D.expand(Box3D.empty(), box, Vec3.create(pad, pad, pad));
     const extent = Vec3.sub(Vec3.zero(), expandedBox.max, expandedBox.min)