Refract the shard with the ice again and make it bigger

It is sampled at the refracted position like every other sheet, so the
cracks cut across it and bend its silhouette; SHARD 0.70 -> 0.95.

9_ice_over_obj.frag

@@ -87,9 +87,7 @@ void main() {
     float depth = solid ? OBJECT_DEPTH
                         : texture2D(u_scene, atlasUV(hit.xy + par, layer)).a * 2.6;
     float path = (hit.z - (FRONT - depth)) / -inside.z;                     // ice crossed to reach this sheet
-    // The shard keeps its shape: it is sampled without the refraction offset, so it
-    // stays one solid piece instead of being cut up by the crack steps.
-    vec2 at = solid ? hit.xy + par * 0.5 : (hit + inside * path).xy + par;
+    vec2 at = (hit + inside * path).xy + par;
     vec3 plasma;
     plasma.r = texture2D(u_scene, atlasUV(at + shearR * path, layer)).r;
     plasma.g = texture2D(u_scene, atlasUV(at, layer)).g;