workaround to make lines stick to ground, avoid artifacts

vis3d/unity/Assets/_app/shaders/line.shader

@@ -40,6 +40,7 @@
       {
         v2f o;
         o.vertex = UnityObjectToClipPos(v.vertex);
+        o.vertex.z = 0; //HACK: Make lines stick to ground without weird artifacts.
         o.uv = TRANSFORM_TEX(v.uv, _MainTex);
         o.color = v.color;
         UNITY_TRANSFER_FOG(o,o.vertex);
@@ -54,7 +55,7 @@
       {
         // sample the texture
         //fixed4 col = tex2D(_MainTex, i.uv);
-        float t = _Time.b;
+        float t = _Time.r;
         t = t % 1.0;
         float x = i.color.r + t;
         x = x % 2 - 1; //[-1..1]
@@ -63,6 +64,9 @@
         float4 red = _Color;
         fixed4 col = red * clamp(f(x+t, 20), 0, 1);
 
+        //TEST
+        //col = _Color;
+
       // apply fog
       UNITY_APPLY_FOG(i.fogCoord, col);
       return col;