Environment Map Analysis: the model's faces as a mirror reflecting a studio (sky, horizon band, floor with light streaks, two light panels); toggles like the other surface analyses

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AS5Tn3xieewUSg3uxrMVdL

crates/ui-egui/src/gpu.rs

@@ -257,6 +257,21 @@ fn analysis(i: TOut) -> vec4<f32> {
         let c = select(0.08, 0.95, s > 0.0);
         return out_color(vec4<f32>(vec3<f32>(c), 1.0));
     }
+    if (u.ana.x > 3.5) {
+        // A studio around the model: sky above, a dark floor below, a bright horizon band and
+        // two soft light panels, seen in a mirror.
+        let r = reflect(-v, n);
+        var c = mix(vec3<f32>(0.32, 0.34, 0.38), vec3<f32>(0.80, 0.86, 0.95), smoothstep(-0.05, 0.6, r.z));
+        c = c + vec3<f32>(0.6) * exp(-abs(r.z) * 40.0);
+        let side = atan2(r.y, r.x);
+        c = c + vec3<f32>(0.9) * smoothstep(0.92, 0.98, cos(side * 2.0)) * smoothstep(0.1, 0.3, r.z) * smoothstep(0.8, 0.6, r.z);
+        if (r.z < -0.02) {
+            // The floor: lighter toward the horizon, with light-panel streaks along it.
+            c = mix(vec3<f32>(0.55, 0.56, 0.60), vec3<f32>(0.20, 0.20, 0.22), clamp(-r.z * 1.6, 0.0, 1.0));
+            c = c + vec3<f32>(0.35) * smoothstep(0.95, 0.99, cos(side * 3.0));
+        }
+        return out_color(vec4<f32>(min(c, vec3<f32>(1.0)), 1.0));
+    }
     if (u.ana.x < 2.5) {
         let a = degrees(asin(clamp(dot(normalize(i.n), normalize(u.pull.xyz)), -1.0, 1.0)));
         var c = vec3<f32>(0.95, 0.80, 0.15);

crates/ui-egui/src/icons.rs

@@ -652,6 +652,15 @@ pub fn paint(p: &Painter, r: Rect, name: &str, ink: Color32, fill: Color32, acce
                 pen.line(&[(3.0 + 12.0 * t, 17.0 + 2.0 * t), (9.0 + 12.0 * t, 5.0 + 2.0 * t)], a);
             }
         }
+        "environment_map" => {
+            let pts: Vec<Pos2> =
+                (0..32).map(|i| i as f32 / 32.0 * std::f32::consts::TAU).map(|t| pen.at(12.0 + 9.0 * t.cos(), 12.0 + 9.0 * t.sin())).collect();
+            p.add(Shape::convex_polygon(pts, Color32::from_rgb(190, 205, 230), Stroke::new(pen.w, ink)));
+            pen.poly(&[(3.6, 13.0), (20.4, 13.0), (18.5, 17.5), (5.5, 17.5)], Color32::from_rgb(60, 62, 70), Color32::TRANSPARENT);
+            pen.line(&[(3.2, 12.6), (20.8, 12.6)], Color32::WHITE);
+            p.circle_filled(pen.at(9.0, 8.0), 2.2 * pen.s(), Color32::WHITE);
+            pen.circle(12.0, 12.0, 9.0, Color32::TRANSPARENT, ink);
+        }
         "zebra" | "draft_analysis" | "curvature_map" => {
             let pts: Vec<Pos2> =
                 (0..32).map(|i| i as f32 / 32.0 * std::f32::consts::TAU).map(|t| pen.at(12.0 + 9.0 * t.cos(), 12.0 + 9.0 * t.sin())).collect();

crates/ui-egui/src/sketch_tools.rs

@@ -101,7 +101,11 @@ pub fn start_hook(app: &mut SolveApp, id: &str) -> bool {
         ("FusionZebraAnalysisCommand", Some(A::Zebra { .. })) => Some(true),
         ("FusionDraftAnalysisCommand", Some(A::Draft { .. })) => Some(true),
         ("FusionCurvatureMapAnalysisCommand", Some(A::Curvature { .. })) => Some(true),
-        ("FusionZebraAnalysisCommand" | "FusionDraftAnalysisCommand" | "FusionCurvatureMapAnalysisCommand", _) => Some(false),
+        ("FusionEnvironmentMapAnalysisCommand", Some(A::Environment)) => Some(true),
+        (
+            "FusionZebraAnalysisCommand" | "FusionDraftAnalysisCommand" | "FusionCurvatureMapAnalysisCommand" | "FusionEnvironmentMapAnalysisCommand",
+            _,
+        ) => Some(false),
         _ => None,
     };
     if let Some(on) = same {

crates/ui-egui/src/viewport.rs

@@ -653,6 +653,7 @@ fn analysis_uniform(app: &SolveApp) -> [f32; 8] {
         Some(A::Zebra { stripes }) => [1.0, stripes as f32, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0],
         Some(A::Draft { pull, angle }) => [2.0, angle as f32, 0.0, 0.0, pull.x as f32, pull.y as f32, pull.z as f32, 0.0],
         Some(A::Curvature { radius }) => [3.0, radius as f32, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0],
+        Some(A::Environment) => [4.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0],
         None => [0.0; 8],
     }
 }