Surface world: grass in daylight, forests, cliffs with cave mouths; free-game and editor option

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/render3d.rs

@@ -449,6 +449,10 @@ fn ambient_field(map: &Map) -> Vec<f32> {
             (false, Owner::Hero) => 0.6,
             _ => 0.0,
         };
+        // daylight above ground (cliffs and trees too)
+        if map.sky(i) {
+            f[i] = 1.6;
+        }
         if t.river() == Some(Kind::Lava) {
             f[i] = f[i].max(0.8); // lava lights up its surroundings
         }
@@ -672,7 +676,11 @@ fn build_chunk(map: &Map, amb: &[f32], glow: &[f32], cx: i32, cz: i32, atlas: &T
     for z in cz * CHUNK..((cz + 1) * CHUNK).min(mh() as i32) {
         for x in cx * CHUNK..((cx + 1) * CHUNK).min(mw() as i32) {
             let t = map.t[idx(x, z)];
-            let tex = Gfx::tile_tex(t.kind, t.owner, t.var, t.reinforced);
+            let mut tex = Gfx::tile_tex(t.kind, t.owner, t.var, t.reinforced);
+            // open land above ground is grass (until a master claims it)
+            if map.sky(idx(x, z)) && t.kind == Kind::Floor && t.owner == Owner::None {
+                tex = T_GRASS + (t.var as u32 & 3);
+            }
             let (ua, ub) = cell_uv(tex);
             let (xf, zf) = (x as f32, z as f32);
             if !map.shown(idx(x, z)) {
@@ -836,11 +844,13 @@ fn build_chunk(map: &Map, amb: &[f32], glow: &[f32], cx: i32, cz: i32, atlas: &T
                     c,
                     [Vec3::Y; 4],
                 );
-                // outlines: north and west edge, only between two open tiles (each edge once)
-                if !solid_at(map, x, z - 1) {
+                // outlines: north and west edge, only between two open tiles (each edge once);
+                // open land above ground has none
+                let outdoors = map.sky(idx(x, z)) && t.owner == Owner::None;
+                if !solid_at(map, x, z - 1) && !outdoors {
                     ln.strip(vec3(xf, 0.0, zf), vec3(xf + 1.0, 0.0, zf), Vec3::Y, OUTLINE_W, OUTLINE_C);
                 }
-                if !solid_at(map, x - 1, z) {
+                if !solid_at(map, x - 1, z) && !outdoors {
                     ln.strip(vec3(xf, 0.0, zf), vec3(xf, 0.0, zf + 1.0), Vec3::Y, OUTLINE_W, OUTLINE_C);
                 }
                 // room decor
@@ -871,7 +881,7 @@ fn build_chunk(map: &Map, amb: &[f32], glow: &[f32], cx: i32, cz: i32, atlas: &T
                     }
                 }
                 // wear and tear: grit and cracks on plain floors
-                if matches!(t.kind, Kind::Floor) {
+                if matches!(t.kind, Kind::Floor) && !outdoors {
                     let hsh = (x as u32).wrapping_mul(2654435761) ^ (z as u32).wrapping_mul(2246822519);
                     let hsh = (hsh ^ (hsh >> 15)).wrapping_mul(2246822519);
                     let decal = match hsh % 11 {
@@ -1083,7 +1093,7 @@ fn chunk_sig(map: &Map, cx: i32, cz: i32) -> u64 {
                         Kind::Drawbridge => t.res as u64,
                         _ => 0,
                     };
-                    let shown = map.shown(idx(x, z)) as u64;
+                    let shown = map.shown(idx(x, z)) as u64 | (map.sky(idx(x, z)) as u64) << 1;
                     (t.kind as u64) | (t.owner as u64) << 5 | (t.marked as u64) << 8 | (t.reinforced as u64) << 9 | shown << 10 | extra << 11
                 }
                 None => 0xff,
@@ -1462,7 +1472,9 @@ impl R3d {
         let amb = |x: f32, z: f32| {
             let (ix, iz) = (x as i32, z as i32);
             let own = g.map.get(ix, iz).map_or(false, |t| t.owner == Owner::Player);
-            if own {
+            if inb(ix, iz) && g.map.sky(idx(ix, iz)) {
+                0.95
+            } else if own {
                 0.75
             } else {
                 0.5