Merge remote-tracking branch 'origin/visual'

Deep fog noise scroll speed 0.045/0.03 → 0.06/0.045 to match D-059
15-20s breathing cycle spec. Clamp sample_visibility() UV coordinates
to [0,1] to prevent sticky gradient at map edges.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/scripts/protocol/protocol.gd

@@ -11,7 +11,7 @@ class_name Protocol
 
 ## Protocol version — must match server PROTOCOL_VERSION in bridge/types.rs.
 ## Reject snapshots where version != this value.
-const PROTOCOL_VERSION: int = 16
+const PROTOCOL_VERSION: int = 17
 
 
 # -- Decode: bytes from server → GDScript types --------------------------------

client/shaders/fog.gdshader

@@ -22,10 +22,35 @@ uniform float time;          // Seconds since start
 const vec3 UNEXPLORED_COLOR = vec3(0.071, 0.078, 0.102);  // #12141a
 const vec3 DARK_OVERLAY = vec3(0.02, 0.02, 0.05);
 
-// D-059 thresholds (after bilinear filtering)
+// D-059 thresholds
 // Forward tiles = 1.0, Peripheral = 0.706 (180/255), not-visible = 0.0
 const float CLEAR_THRESHOLD = 0.85;   // Above this: fully clear
-const float PERIPHERAL_LOW = 0.55;    // Below this: transition to deep/unexplored
+// Lowered from 0.55 to capture blur-extended gradient tiles in the peripheral
+// branch. The 7x7 Gaussian (sigma 2.0) produces values down to ~0.08 at
+// 3 tiles from the LOS boundary — together with bilinear interpolation this
+// yields the 6-8 sim tile soft edge specified by D-059/D-066.
+const float PERIPHERAL_LOW = 0.08;
+
+// D-059: Soft gradient via 7x7 Gaussian blur on visibility (sigma 2.0).
+// The visibility texture is 1 texel per sim tile with discrete values
+// (0 / 180 / 255). Bilinear filtering alone only smooths across ~1 tile.
+// This blur spreads the LOS boundary into a 3-4 tile radius gradient;
+// combined with smoothstep transitions, produces 6-8 tile soft edge.
+// 49 taps from a tiny (~128x128) fully-cached texture — well under 1ms.
+float sample_visibility(vec2 uv) {
+    vec2 t = 1.0 / map_size;
+    float sum = 0.0;
+    float weight = 0.0;
+    for (float dy = -3.0; dy <= 3.0; dy += 1.0) {
+        for (float dx = -3.0; dx <= 3.0; dx += 1.0) {
+            float w = exp(-(dx * dx + dy * dy) / 8.0);
+            vec2 sample_uv = clamp(uv + vec2(dx, dy) * t, vec2(0.0), vec2(1.0));
+            sum += texture(visibility_tex, sample_uv).r * w;
+            weight += w;
+        }
+    }
+    return sum / weight;
+}
 
 void fragment() {
     // Map UV (0-1 across ColorRect) to world pixels, then to tile coordinates
@@ -39,31 +64,41 @@ void fragment() {
     if (tex_uv.x < 0.0 || tex_uv.x > 1.0 || tex_uv.y < 0.0 || tex_uv.y > 1.0) {
         COLOR = vec4(UNEXPLORED_COLOR, 1.0);
     } else {
-        float vis = texture(visibility_tex, tex_uv).r;
+        float vis_raw = texture(visibility_tex, tex_uv).r;
+        float vis = sample_visibility(tex_uv);
         float explored = texture(exploration_tex, tex_uv).r;
 
+        // Don't bleed gradient into never-explored tiles — keep them Layer 5
+        if (explored < 0.01 && vis_raw < 0.01) {
+            vis = 0.0;
+        }
+
         if (vis > PERIPHERAL_LOW) {
             // In or near vision cone
             if (vis > CLEAR_THRESHOLD) {
                 // Layer 1: Clear — soft edge gradient
+                // Alpha matches Layer 2 at boundary (coverage=1.0 → 0.25) for continuity
                 float edge = smoothstep(CLEAR_THRESHOLD, 1.0, vis);
-                COLOR = vec4(0.0, 0.0, 0.0, 1.0 - edge);
+                COLOR = vec4(DARK_OVERLAY, 0.25 * (1.0 - edge));
             } else {
                 // Layer 2: Light fog (peripheral + forward edge)
                 // D-059: animated Perlin noise, 8-10s cycle
                 float noise_val = texture(noise_tex, tile * 0.03 + vec2(time * 0.11, time * 0.07)).r;
                 float coverage = smoothstep(PERIPHERAL_LOW, CLEAR_THRESHOLD, vis);
-                // Blend from heavy fog (alpha ~0.55) to lighter fog near clear edge
-                float alpha = mix(0.55, 0.25, coverage) + noise_val * 0.1;
+                // Blend from heavy fog (alpha ~0.38) to lighter fog near clear edge
+                // Taper noise to zero near the clear boundary — preserves breathing in deep
+                // peripheral but keeps the Layer 1/2 transition clean (no curly edge)
+                float noise_weight = 1.0 - smoothstep(0.5, 1.0, coverage);
+                float alpha = mix(0.38, 0.25, coverage) + noise_val * 0.05 * noise_weight;
                 COLOR = vec4(DARK_OVERLAY, alpha);
             }
         } else if (explored > 0.3) {
             // Layer 3: Deep fog (previously explored, no longer in LOS)
             // D-059: near-monochrome, ~10% zone temperature tint, 15-20s breathing cycle
             vec3 zone_tint = texture(zone_tint_tex, tex_uv).rgb;
-            float noise_val = texture(noise_tex, tile * 0.015 + vec2(time * 0.045, time * 0.03)).r;
+            float noise_val = texture(noise_tex, tile * 0.015 + vec2(time * 0.06, time * 0.045)).r;
             vec3 tint_color = mix(vec3(0.04), zone_tint, 0.1);
-            float alpha = mix(0.78, 0.90, noise_val);  // Fog breathes
+            float alpha = mix(0.62, 0.76, noise_val);  // Fog breathes
             COLOR = vec4(tint_color, alpha);
         } else {
             // Layer 5: Unexplored, no maps — information zero