add new snow shader

core/daynight/environment_management.tscn

@@ -258,7 +258,7 @@ draw_pass_1 = SubResource("QuadMesh_ruhh7")
 [node name="Particles_Rain" type="GPUParticles3D" parent="." unique_id=1543042897]
 transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 30, 0)
 cast_shadow = 0
-extra_cull_margin = 10.0
+extra_cull_margin = 16384.0
 emitting = false
 amount = 5000
 lifetime = 1.5

core/daynight/snow.gdshader

@@ -8,6 +8,12 @@ global uniform float global_snow_melt_speed        = 0.1;
 global uniform float global_snow_threshold         = 0.5;
 global uniform vec4  global_snow_color             = vec4(0.92, 0.96, 1.0, 1.0);
 
+uniform sampler2D noise_texture : filter_linear_mipmap, repeat_enable;
+uniform float noise_scale : hint_range(0.01, 1.0) = 0.15;
+uniform float noise_edge_softness : hint_range(0.01, 0.5) = 0.2;
+uniform float roughness_variation : hint_range(0.0, 0.3) = 0.15;
+uniform float color_variation : hint_range(0.0, 0.15) = 0.05;
+
 void fragment() {
     float snow_amount = 0.0;
     if (global_snow_start_time >= 0.0) {
@@ -19,12 +25,27 @@ void fragment() {
         snow_amount = snow_amount * (1.0 - melt);
     }
 
+    vec3 world_pos = (INV_VIEW_MATRIX * vec4(VERTEX, 1.0)).xyz;
     vec3 world_normal = (INV_VIEW_MATRIX * vec4(NORMAL, 0.0)).xyz;
-    float facing_up   = clamp(world_normal.y, 0.0, 1.0);
-    float snow_factor = smoothstep(global_snow_threshold, 1.0, facing_up) * snow_amount;
+    float facing_up = clamp(world_normal.y, 0.0, 1.0);
 
-    ALBEDO    = global_snow_color.rgb;
-    ROUGHNESS = 0.15;
+    float noise_val = texture(noise_texture, world_pos.xz * noise_scale).r;
+
+    float edge = smoothstep(
+        global_snow_threshold - noise_edge_softness,
+        global_snow_threshold + noise_edge_softness,
+        facing_up + (noise_val - 0.5) * 0.4
+    );
+    float coverage = smoothstep(0.0, 0.6, noise_val + snow_amount - 0.4);
+    float snow_factor = edge * coverage * snow_amount;
+
+    float shade = mix(-color_variation, color_variation, noise_val);
+    vec3 snow_albedo = clamp(global_snow_color.rgb + vec3(shade), 0.0, 1.0);
+
+    float snow_roughness = mix(0.15 - roughness_variation, 0.15 + roughness_variation, noise_val);
+
+    ALBEDO    = snow_albedo;
+    ROUGHNESS = snow_roughness;
     METALLIC  = 0.0;
     ALPHA     = snow_factor;
 }

core/daynight/snow_overlay.tres

@@ -5,3 +5,7 @@
 [resource]
 render_priority = 0
 shader = ExtResource("1_vwtmf")
+shader_parameter/noise_scale = 0.15
+shader_parameter/noise_edge_softness = 0.2
+shader_parameter/roughness_variation = 0.15
+shader_parameter/color_variation = 0.05