Fix the depth prepass artefacts

client/client_recv.js

@@ -178,7 +178,7 @@ function handle_event(state, context, event, options = {}) {
             event.index = state.events.length;
             event.starting_index = state.starting_index;
 
-            if (event.points.length > 0) {
+            if (event.points.length > 1) {
                 state.starting_index += (event.points.length - 1) * 4;
             }
 

client/webgl_shaders.js

@@ -125,7 +125,7 @@ const sdf_vs_src = `#version 300 es
         vec2 screen02 = screen01 * 2.0;
 
         // Inflate quad by 1 pixel
-        float apron = 1.0;
+        float apron = 2.0;
         vec2 line_dir = normalize(a_line.zw - a_line.xy);
         vec2 up_dir = vec2(line_dir.y, -line_dir.x);
         vec2 pixel = vec2(2.0) / u_res * apron;