show snow on grass

core/daynight/weather_overlay.gdshader

@@ -17,6 +17,8 @@ global uniform float global_snow_cap_flatness_end  = 0.96;
 global uniform float global_snow_cap_noise_scale   = 0.22;
 global uniform float global_snow_cap_noise_strength = 0.18;
 const float SNOW_VISUAL_RESPONSE = 0.55;
+const float FULL_SNOW_VISUAL_START = 0.82;
+const float FULL_SNOW_VISUAL_END = 0.98;
 uniform bool snow_noise_enabled = true;
 uniform float snow_noise_scale : hint_range(0.01, 1.0) = 0.15;
 uniform float snow_edge_softness : hint_range(0.01, 0.5) = 0.2;
@@ -156,6 +158,8 @@ void fragment() {
     float snow_factor = max(snow_edge * snow_coverage, flat_accumulation);
     float snow_opacity = clamp(snow_factor, 0.0, 1.0);
     snow_opacity = max(snow_opacity, flat_accumulation * mix(0.45, 0.9, snow_noise_mask));
+    float full_snow_opacity = snow_edge * smoothstep(FULL_SNOW_VISUAL_START, FULL_SNOW_VISUAL_END, snow_progress);
+    snow_opacity = max(snow_opacity, full_snow_opacity);
 
     float shade = mix(-snow_color_variation, snow_color_variation, noise_val);
     vec3 snow_albedo = clamp(global_snow_color.rgb + vec3(shade), 0.0, 1.0);