diff --git a/README.md b/README.md
index 4b0293a..5bdda85 100644
--- a/README.md
+++ b/README.md
@@ -13,6 +13,7 @@ This repository currently contains:
 - An implementation roadmap under `docs/plans/`.
 - Legal and reference-material hygiene notes under `docs/legal/` and `docs/research/`.
 - A clean-room terrain import boundary with project-owned `ovp-text` fixtures, a PNG heightmap script importer, an SRTM/HGT byte importer behind the `hgt` Cargo feature, an ESRI ASCII Grid parser behind the `ascii-grid-import` feature, and a deterministic terrain-generation module in `src/terrain_gen.rs` with `TerrainGenerationSpec` / `DeterministicTerrainGenerator` (see `cargo test terrain_gen` and its determinism/seed note).
+- A project-owned script parser + executor in `src/script.rs` / `src/script_exec.rs`, MakePath-inspired camera path generation in `src/path.rs`, a project-owned color-map model with editable thresholds/bands in `src/scene.rs`, and an `app` feature shell with working import/script/path/project controls in `src/app_state.rs`, `src/app.rs`, and `src/ui_shell.rs`.
 
 ## Development
 
@@ -24,6 +25,7 @@ cargo run -- scene export --output /tmp/openvistapro-default.ovp.toml
 cargo run -- render --preset hill --width 256 --height 256 --output /tmp/openvistapro-hill.png
 cargo run -- render --preset hill --scene /tmp/openvistapro-default.ovp.toml --width 256 --height 256 --output /tmp/openvistapro-hill-from-scene.png
 cargo run -- render --preset hill --camera-demo --width 256 --height 192 --output /tmp/openvistapro-perspective.png
+cargo run -- render --preset hill --quality final --output /tmp/openvistapro-renders/
 cargo run --features app --bin openvistapro_app
 ```
 
@@ -56,6 +58,7 @@ cargo test --all-features
 ```
 
 The default `render` mode writes a deterministic top-down elevation preview.
+Passing `--quality preview|balanced|final` selects the project-owned quality profile; if `--output` points to an existing directory, the renderer derives a quality-specific PNG name there.
 Passing `--camera-demo` switches to the current CPU perspective renderer spike:
 a simple pinhole-camera raymarcher with bilinear height sampling, fixed step
 size, sky gradient, and distance haze. It is intended as a readable reference
@@ -64,9 +67,10 @@ model.
 
 Scene files use the project-owned `.ovp.toml` format. Version 1 stores a
 top-level `schema = "openvistapro.scene"`, `version = 1`, and a serialized
-`Scene` payload containing camera, light, water, tree-line, snow-line, and haze
-settings. The format is intentionally human-readable while the data model is
-still evolving.
+`Scene` payload containing camera position/target, camera heading-pitch-bank,
+lens/FOV/clip ranges, light, water, tree-line, snow-line, haze, and hydrology
+overlays/settings. The format is intentionally human-readable while the data
+model is still evolving.
 
 ## Script language (MVP)
 
diff --git a/docs/knowledgebase/feature-inventory.md b/docs/knowledgebase/feature-inventory.md
index 6fc8aff..f32a3a5 100644
--- a/docs/knowledgebase/feature-inventory.md
+++ b/docs/knowledgebase/feature-inventory.md
@@ -3,9 +3,9 @@
 This is a normalized reconciliation of the VistaPro manuals, MakePath guide, screenshots, and current OpenVistaPro implementation.
 
 Status counts by normalized feature family:
-- Implemented: 7
-- Partial: 7
-- Planned: 6
+- Implemented: 12
+- Partial: 5
+- Planned: 3
 
 Notes:
 - “Implemented” means the current codebase has a working, tested slice for that family.
@@ -22,21 +22,21 @@ Notes:
 | GeoTIFF terrain import | Modern open terrain source, not a legacy VistaPro format. | Implemented | `src/import/geotiff.rs` behind `import-geotiff`, tests in that module. | Deliberately narrow subset: tiny synthetic single-band raster support only. |
 | Fractal / synthetic terrain generation | VistaPro overview calls out fractal landscapes and generated terrain. | Partial | `src/terrain.rs` (`plane`, `radial_hill`), `src/app_state.rs` presets. | Current terrain generation is only deterministic fixtures, not a true fractal/noise terrain engine. |
 | Camera and target placement | VistaPro 2 / 3 manuals: “Setting Camera and Target”; screenshot workflow uses camera/target gadgets. | Implemented | `src/scene.rs` (`Camera`), `src/app.rs` (camera position/target controls), `src/app_state.rs`. | Only the core position/target slice exists; there is no map-click placement UI yet. |
-| Lens / range / orientation controls | VistaPro manuals describe lens/range, bank, heading, and pitch controls. | Partial | `src/scene.rs` (`Camera.fov_degrees`), `src/render.rs` perspective renderer. | No explicit bank/heading/pitch model or legacy lens/range UI yet. |
-| Water / sea level, tree line, snow line, haze | Manuals repeatedly mention tree line, snow line, water level, haze, and atmospheric tuning. | Implemented | `src/scene.rs`, `src/app.rs` sliders, `src/colormap.rs`, `src/render.rs`. | Rivers/lakes are still missing, but the core elevation-band controls are present. |
-| Rivers and lakes | VistaPro manuals explicitly mention rivers and lakes as adjustable landscape features. | Planned | Not yet represented in `Scene` or renderer code. | Add hydrology controls/data model before claiming this family. |
+| Lens / range / orientation controls | VistaPro manuals describe lens/range, bank, heading, and pitch controls. | Implemented | `src/scene.rs` (`Camera.orientation`, `fov_degrees`, `near_range`, `far_range`), `src/render.rs` perspective renderer, `src/app.rs` explicit heading/pitch/bank and lens/range controls. | The modern shell keeps the camera model explicit while staying intentionally simpler than the legacy lens matrix and stereo workflows. |
+| Water / sea level, tree line, snow line, haze | Manuals repeatedly mention tree line, snow line, water level, haze, and atmospheric tuning. | Implemented | `src/scene.rs`, `src/app.rs` sliders, `src/colormap.rs`, `src/render.rs`. | The core elevation-band controls are present and still feed the renderer. |
+| Rivers and lakes | VistaPro manuals explicitly mention rivers and lakes as adjustable landscape features. | Implemented | `src/scene.rs` (`Hydrology` lake/river overlays), `src/app.rs` hydrology controls + reset button, `src/app_state.rs`, `src/render.rs`, `src/scene_file.rs`, tests in `src/scene.rs`, `src/render.rs`, and `src/app_state.rs`. | The first clean-room slice now exposes editable lake/river overlays; routed-water simulation and drainage maps can grow later. |
 | Light direction and custom lighting | Manuals discuss sunlight placement and lighting experiments. | Partial | `src/scene.rs` (`Light`), `src/render.rs`, `src/app.rs` (light state exists in the scene model even if UI is minimal). | The current model is much simpler than VistaPro’s lighting workflow and lacks richer light controls. |
-| Vertical exaggeration | VistaPro manuals describe vertical scaling / scene exaggeration controls. | Planned | No dedicated field or control in the current scene model. | Add an explicit vertical-scale parameter and render integration. |
-| Color maps / palettes / texture image loading | VistaPro 3 manual includes loading PCX images, adding texture, and saving/loading color maps. | Partial | `src/colormap.rs` fixed bands, `src/render.rs` uses scene thresholds. | No color-map editor, no palette import/export, and no PCX/texture loading yet. |
+| Vertical exaggeration | VistaPro manuals describe vertical scaling / scene exaggeration controls. | Implemented | `src/scene.rs` (`Scene.vertical_exaggeration`), `src/app.rs`, `src/app_state.rs`, `src/render.rs`, tests in `src/render.rs`, and scene-file round-trips in `src/scene_file.rs`. | The basic scene-level exaggeration slice is now wired through the shell, renderer, and scene files; future work can explore per-tool or legacy-style exaggeration workflows. |
+| Color maps / palettes / texture image loading | VistaPro 3 manual includes loading PCX images, adding texture, and saving/loading color maps. | Implemented | `src/scene.rs` (`Palette` thresholds/bands + colors), `src/app.rs` color-map editor, `src/colormap.rs`, `src/render.rs`, `src/script_exec.rs`, `src/scene_file.rs`. | Palette import/export and PCX/texture loading remain future clean-room work. |
 | Preview / final render workflow | VistaPro manuals describe rough preview rendering and full render output. | Implemented | `src/render.rs` (`render_top_down`, `render_perspective`), `src/cli.rs` (`render`), tests in `src/render.rs`. | The preview/final split is still simplified, but the core render outputs are working. |
-| Render quality presets / smoothing / detail tradeoffs | VistaPro manuals describe quality menus and poly/detail tradeoffs. | Planned | No dedicated quality preset system in current code. | Add explicit quality presets or a render-quality profile object. |
+| Render quality presets / smoothing / detail tradeoffs | VistaPro manuals describe quality menus and poly/detail tradeoffs. | Implemented | `src/render.rs` (`RenderQualityPreset`, quality-aware top-down/perspective render helpers), `src/cli.rs` (`--quality`, output-path resolution), `src/app_state.rs`, `src/app.rs`, tests in `src/render.rs`, `src/app_state.rs`, and `src/cli.rs`. | The project-owned quality profile slice now toggles preview/balanced/final tradeoffs for both the CLI spike and the egui shell. |
 | Scene file save/load (`.ovp.toml`) | Not a VistaPro legacy format; this is the clean-room OpenVistaPro scene format. | Implemented | `src/scene_file.rs`, `src/cli.rs` (`scene export`), tests in `src/scene_file.rs`. | No gap for the project-owned scene format slice. |
-| Script language parser | MakePath guide and VistaPro manual describe scripts and “Run Script” workflows. | Partial | `src/script.rs` parser, tests in `src/script.rs`, `README.md` script section. | Parser exists, but script execution is intentionally deferred. |
-| Script execution and animation frames | MakePath guide says scripts should render full animations and VistaPro can run scripts from the Script menu. | Planned | No script runner or frame-sequencing engine exists yet. | Add execution semantics once the command model is stable. |
-| MakePath-style path generation and motion models | MakePath guide describes spline nodes, previewing a path, and vehicle models (jet, glider, dune buggy, motorcycle, helicopter, cruise missile, custom). | Planned | No path generator or motion-model layer exists yet. | This is a separate planner/animation feature, not just a script parser. |
-| UI shell, menus, dialogs, and numeric gadgets | VistaPro screenshots/manuals show dense menus, dialogs, map tools, and numeric gadgets. | Partial | `src/app.rs`, `src/app_state.rs`, `src/ui_shell.rs`, `src/bin/openvistapro_app.rs`. | OpenVistaPro now has a durable docked egui shell with stable navigation, sidebar, viewport, inspector, and status chrome; menus/dialogs/numeric gadgets still remain to be filled in. |
-| Legacy image / landscape export formats | VistaPro manuals mention saving rendered images and landscapes in formats like IFF/IFF24/RGB and DEM/binary landscape files. | Planned | Current output is PNG plus project-owned `.ovp.toml` scenes. | Add separate compatibility/export work only after the clean internal pipeline is stable. |
+| Script language parser | MakePath guide and VistaPro manual describe scripts and “Run Script” workflows. | Implemented | `src/script.rs`, `src/script_exec.rs`, `src/cli.rs` (`script run`), `src/app_state.rs` script preview, `README.md` script section, tests in `src/script.rs` and `src/script_exec.rs`. | The project-owned grammar is now parsed and executed; any future work should focus on richer syntax or animation export, not basic parser support. |
+| Script execution and animation frames | MakePath guide says scripts should render full animations and VistaPro can run scripts from the Script menu. | Implemented | `src/script_exec.rs` (`run_script` / `run_script_source`), `src/cli.rs` (`script run`), `src/app.rs` script controls, `src/app_state.rs`, tests in `src/script_exec.rs`. | The executor now runs preset/import/render slices; animation-frame sequencing is still a future extension. |
+| MakePath-style path generation and motion models | MakePath guide describes spline nodes, previewing a path, and vehicle models (jet, glider, dune buggy, motorcycle, helicopter, cruise missile, custom). | Implemented | `src/path.rs`, `src/app_state.rs` (`make_path`), `src/app.rs` path controls, tests in `src/path.rs` and `src/app_state.rs`. | Core camera-path generation is now present; editable nodes, vehicle-specific motion models, and script export remain future expansion points. |
+| UI shell, menus, dialogs, and numeric gadgets | VistaPro screenshots/manuals show dense menus, dialogs, map tools, and numeric gadgets. | Partial | `src/app.rs`, `src/app_state.rs`, `src/ui_shell.rs`, `src/bin/openvistapro_app.rs`, plus the `app` feature shell tests. | OpenVistaPro now has a durable docked egui shell with stable navigation, working import/script/path/project actions, sidebar, viewport, inspector, and status chrome; legacy-style menus/dialogs and more specialized gadgets still remain to be filled in. |
+| Legacy image / landscape export formats | VistaPro manuals mention saving rendered images and landscapes in formats like IFF/IFF24/RGB and DEM/binary landscape files. | Planned | Current output is PNG plus project-owned `.ovp.toml` scenes. | Separate compatibility/export work remains future scope after the clean internal pipeline is stable. |
 
 ## Current reconciliation summary
 
-OpenVistaPro already covers the core clean-room pipeline: terrain grids, open importers, scene state, preview/final rendering, project-owned scene files, and a small script parser. The remaining VistaPro-specific gaps cluster around legacy compatibility, richer scene controls, script execution, MakePath-style animation tooling, and the old dense UI/menu workflow.
+OpenVistaPro already covers the core clean-room pipeline: terrain grids, open importers, scene state, preview/final rendering, quality-profile tradeoffs, project-owned scene files, script execution, MakePath-style path generation, editable color-map thresholds/bands, and scene-level vertical exaggeration. The remaining VistaPro-specific gaps cluster around legacy compatibility, richer scene controls, animation-frame export, and the old dense UI/menu workflow.
diff --git a/docs/knowledgebase/ui-panel-map.md b/docs/knowledgebase/ui-panel-map.md
index baf42ad..1a42f70 100644
--- a/docs/knowledgebase/ui-panel-map.md
+++ b/docs/knowledgebase/ui-panel-map.md
@@ -6,14 +6,14 @@ This is a normalized modern shell map derived from the VistaPro manuals, screens
 
 | Modern panel | VistaPro surfaces it absorbs | Suggested placement | Current code support | Notes / gaps |
 |---|---|---|---|---|
-| Viewport / preview | Main render window, map preview, perspective view, preview/final render output | Center dock | Partial | `src/app.rs` already renders the CPU preview into `CentralPanel`; perspective and top-down preview modes exist, but there is no GPU viewport or direct manipulation overlay yet. |
-| Terrain / import | Load Landscape, Import, terrain source selection, generated terrain presets | Left dock or collapsible section | Partial | The current shell exposes project-owned terrain presets (`Plane`, `RadialHill`) and a placeholder import entry point; legacy format import UI is still absent. |
-| Scene / camera | Camera and target gadgets, lens/range, bank/heading/pitch, water/tree/snow/haze controls | Left dock or inspector stack | Partial | Position/target, orientation, lens/range, vertical exaggeration, palette, and hydrology controls now live in `src/app.rs` and `src/app_state.rs`; `src/scene.rs` and `src/render.rs` carry the model/render semantics. The shell now covers the main VistaPro scene controls, but its camera semantics are intentionally simplified and not yet tied to any map-click placement workflow. |
-| Render | Preview vs final render, quality/smoothing, detail tradeoffs | Left dock, toolbar, or render tab | Partial | Current code toggles top-down vs perspective render mode, but there is no dedicated quality profile or render preset UI. |
-| Scripts / paths | Script menu, Run Script, MakePath path tools, animation-frame workflows | Right dock or modal workflow | Partial | Script parsing exists in the codebase, the shell now surfaces a script editor and placeholder path controls, but execution and path generation are still deferred. |
-| File / project actions | New/Open/Save landscape, scene load/save, export commands | Top bar / file menu | Partial | The shell now shows scene-file status and disabled file actions; load/save execution is still wired only in the backend modules. |
-| Status / feedback | Coordinate readouts, render state, file path, progress, messages | Bottom status bar | Partial | The shell now has a bottom status bar driven by `AppData::ui_snapshot()`. |
-| Deferred features / legacy compatibility | Dense menu hierarchy, advanced lighting, hydrology, vertical exaggeration, palette editing, legacy image/landscape exports | Right dock, tool drawer, or dialogs | Planned | These are best surfaced as future tabs or dialogs rather than cluttering the initial shell. |
+| Viewport / preview | Main render window, map preview, perspective view, preview/final render output | Center dock | Partial | `src/app.rs` renders the CPU preview into `CentralPanel`; perspective and top-down preview modes exist, but there is no GPU viewport or direct manipulation overlay yet. |
+| Terrain / import | Load Landscape, Import, terrain source selection, generated terrain presets | Left dock or collapsible section | Partial | The current shell exposes project-owned terrain presets (`Plane`, `RadialHill`) and a working heightmap import action; legacy format import UI is still absent. |
+| Scene / camera | Camera and target gadgets, lens/range, bank/heading/pitch, water/tree/snow/haze controls | Left dock or inspector stack | Partial | Position/target, explicit heading/pitch/bank controls, lens/FOV/clip range controls, vertical exaggeration, color-map editing, and hydrology overlays now live in `src/app.rs` and `src/app_state.rs`; `src/scene.rs`, `src/render.rs`, and `src/script_exec.rs` carry the model/render semantics. The shell covers the main VistaPro scene controls, but its camera semantics are intentionally simplified and not yet tied to any map-click placement workflow. |
+| Render | Preview vs final render, quality/smoothing, detail tradeoffs | Left dock, toolbar, or render tab | Partial | Current code now exposes preview/balanced/final quality presets alongside top-down vs perspective render mode; the shell still lacks the full legacy menu chrome and fine-grained smoothing sliders. |
+| Scripts / paths | Script menu, Run Script, MakePath path tools, animation-frame workflows | Right dock or modal workflow | Partial | Script parsing/execution and MakePath-style path generation now run end-to-end in the backend; the shell surfaces a script editor, Run Script, and Make Path controls, but animation-frame export and richer path editing are still future work. |
+| File / project actions | New/Open/Save landscape, scene load/save, export commands | Top bar / file menu | Partial | The shell now shows scene-file status and working New/Open/Save controls; legacy menu chrome and export dialogs are still missing. |
+| Status / feedback | Coordinate readouts, render state, file path, progress, messages | Bottom status bar | Present | The shell now has a bottom status bar driven by `AppData::ui_snapshot()`. |
+| Legacy compatibility / advanced dialogs | Dense menu hierarchy, advanced lighting, hydrology, vertical exaggeration, palette editing, legacy image/landscape exports | Right dock, tool drawer, or dialogs | Partial | These are best surfaced as future tabs or dialogs rather than cluttering the initial shell; some sub-features already exist in the backend, but the legacy-style workflow itself is still incomplete. |
 
 ## Recommended shell structure
 
@@ -32,19 +32,19 @@ That layout preserves the VistaPro workflow while making room for modern discove
 | Panel | Code support today | Implementation evidence | Priority |
 |---|---|---|---|
 | Viewport / preview | Present | `src/app.rs` renders the preview into `CentralPanel`; `src/app_state.rs` builds the preview image. | High |
-| Terrain / import | Partial | `TerrainPreset` and `AppAction::SetTerrainPreset` in `src/app_state.rs`; terrain radio buttons in `src/app.rs`. | High |
-| Scene / camera | Partial | `Scene`, camera position/target controls, and scene-band sliders in `src/app.rs` and `src/app_state.rs`. | High |
+| Terrain / import | Partial | `TerrainPreset` and `AppAction::SetTerrainPreset` in `src/app_state.rs`; terrain radio buttons and import action in `src/app.rs`. | High |
+| Scene / camera | Partial | `Scene`, camera position/target controls, explicit heading/pitch/bank controls, and lens/range sliders in `src/app.rs` and `src/app_state.rs`. | High |
 | Render | Partial | `RendererMode` plus preview switching in `src/app_state.rs` and `src/app.rs`. | High |
-| Scripts / paths | Not yet | `docs/knowledgebase/feature-inventory.md` marks scripts and path generation as planned. | Medium |
-| File / project actions | Not yet | `loaded_scene_path` exists in `AppData`, but there is no visible file/project UI yet. | Medium |
-| Status / feedback | Not yet | No dedicated status widget or state binding is present. | Medium |
-| Deferred features / legacy compatibility | Not yet | These remain future work in the feature inventory. | Low |
+| Scripts / paths | Partial | `src/script.rs`, `src/script_exec.rs`, `src/path.rs`, and the script/path controls in `src/app.rs`. | High |
+| File / project actions | Partial | `loaded_scene_path` plus the working New/Open/Save controls in `src/app.rs` and `src/scene_file.rs`. | Medium |
+| Status / feedback | Present | Bottom status bar driven by `AppData::ui_snapshot()` in `src/app.rs`. | Medium |
+| Legacy compatibility / advanced dialogs | Partial | Backend support exists for some sub-features like vertical exaggeration and hydrology, while palette/color-map editing is now wired into the shell; the legacy-style menu/dialog workflow is still incomplete. | Low |
 
 ## Remaining gaps
 
-- No legacy-style menu/dialog layer for file, export, or script workflows.
-- No docked status bar or live feedback line.
-- No dedicated scripts/paths editor surface.
+- No legacy-style menu/dialog layer for file, export, or advanced workflows.
+- The docked status bar exists now, but richer progress and coordinate feedback are still open.
+- No dedicated scripts/paths editor surface beyond the current MVP controls.
 - Palette import/export and legacy texture loading remain open.
 - Hydrology still lacks routed-water simulation and drainage maps.
 - Legacy export and compatibility dialogs remain future work.
diff --git a/docs/plans/phase-4-formats-scripts-ui.md b/docs/plans/phase-4-formats-scripts-ui.md
index 39c8a32..f688886 100644
--- a/docs/plans/phase-4-formats-scripts-ui.md
+++ b/docs/plans/phase-4-formats-scripts-ui.md
@@ -721,20 +721,10 @@ Expected: generated script parses successfully.
 
 ## Milestone G: WGPU/egui application after CLI stability
 
-**Status:** Tasks G1–G4 have landed. `src/app_state.rs` holds testable app state and
-`AppAction` reducers; `src/app.rs` and `src/bin/openvistapro_app.rs` provide the
-`app`-feature `eframe`/`egui` shell. The shell now docks terrain, scene/camera, and render
-controls in a left panel, a scripts/paths panel on the right, a top project bar and a
-bottom status bar for file/status chrome, and the CPU top-down/perspective preview in the
-center. Still-planned actions — heightmap import, run script, make path, and file
-new/open/save — are present as disabled placeholders so the layout is honest about scope.
+**Status:** Tasks G1–G4 have landed. `src/app_state.rs` holds testable app state and `AppAction` reducers; `src/app.rs` and `src/bin/openvistapro_app.rs` provide the `app`-feature `eframe`/`egui` shell. The shell now docks terrain, scene/camera, render, import, script, path, and project controls around the CPU top-down/perspective preview, with a bottom status bar and backend-backed import/script/path actions.
 The shell map is tracked in [`docs/knowledgebase/ui-panel-map.md`](../knowledgebase/ui-panel-map.md).
 
-Remaining UI roadmap: Task G5 (WGPU renderer backend) plus the still-open gaps — wiring
-file/import/script/path actions to their backend modules, legacy menus/dialogs,
-orientation and lens/range controls, vertical exaggeration, a palette editor, and
-hydrology controls. All of it stays clean-room: no proprietary VistaPro assets, menus, or
-screenshots enter the repository.
+Remaining UI roadmap: Task G5 (WGPU renderer backend) plus the still-open gaps — legacy menus/dialogs, richer file/project chrome, animation-frame export, deeper script/path editors, and palette import/export / texture loading. All of it stays clean-room: no proprietary VistaPro assets, menus, or screenshots enter the repository.
 
 ### Task G1: Create app-state crate/module without a window
 
diff --git a/src/app.rs b/src/app.rs
index 23f5f37..61bf48a 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -1,7 +1,7 @@
 use eframe::egui;
 use image::RgbImage;
 
-use crate::app_state::{AppAction, AppData, RendererMode, TerrainPreset};
+use crate::app_state::{AppAction, AppData, RenderQuality, RendererMode, TerrainPreset};
 use crate::scene::Vec3;
 use crate::ui_shell::{ShellSection, UiShellState};
 
@@ -127,6 +127,22 @@ impl OpenVistaProApp {
         if renderer_mode != self.data.renderer_mode {
             self.data.apply(AppAction::SetRendererMode(renderer_mode));
         }
+
+        ui.separator();
+        ui.label("Render quality");
+        let mut quality = self.data.render_quality;
+        changed |= ui
+            .radio_value(&mut quality, RenderQuality::Preview, "Preview")
+            .changed();
+        changed |= ui
+            .radio_value(&mut quality, RenderQuality::Balanced, "Balanced")
+            .changed();
+        changed |= ui
+            .radio_value(&mut quality, RenderQuality::Final, "Final")
+            .changed();
+        if quality != self.data.render_quality {
+            self.data.apply(AppAction::SetRenderQuality(quality));
+        }
         changed
     }
 
@@ -165,24 +181,29 @@ impl OpenVistaProApp {
         self.data.apply(AppAction::SetCameraTarget(camera_target));
 
         ui.separator();
-        ui.label("Camera orientation and lens");
+        ui.label("Camera orientation and lens/range");
         let mut orientation = self.data.scene.camera.orientation;
-        changed |= vec3_controls(ui, "Orientation", &mut orientation);
+        changed |= orientation_controls(ui, &mut orientation);
         self.data
             .apply(AppAction::SetCameraOrientation(orientation));
 
+        ui.small(
+            "Heading turns the camera around world up, pitch tilts it, and bank rolls the horizon.",
+        );
+
         let mut fov_degrees = self.data.scene.camera.fov_degrees;
         let mut near_range = self.data.scene.camera.near_range;
         let mut far_range = self.data.scene.camera.far_range;
         changed |= ui
-            .add(egui::Slider::new(&mut fov_degrees, 10.0..=170.0).text("FOV"))
+            .add(egui::Slider::new(&mut fov_degrees, 10.0..=170.0).text("Lens / FOV (°)"))
             .changed();
         changed |= ui
-            .add(egui::Slider::new(&mut near_range, 0.1..=50.0).text("Near"))
+            .add(egui::Slider::new(&mut near_range, 0.1..=50.0).text("Near clip"))
             .changed();
         changed |= ui
-            .add(egui::Slider::new(&mut far_range, 1.0..=1000.0).text("Far"))
+            .add(egui::Slider::new(&mut far_range, 1.0..=1000.0).text("Far clip"))
             .changed();
+        ui.small("FOV controls lens width; near/far clip distances are in world units.");
         self.data.apply(AppAction::SetCameraLens {
             fov_degrees,
             near_range,
@@ -200,6 +221,13 @@ impl OpenVistaProApp {
 
         ui.separator();
         ui.label("Hydrology");
+        ui.horizontal(|ui| {
+            if ui.button("Reset hydrology").clicked() {
+                self.data.apply(AppAction::ResetHydrology);
+                changed = true;
+            }
+            ui.label("Lake and river overlays are clean-room defaults");
+        });
         let mut river_level = self.data.scene.hydrology.river_level;
         let mut lake_level = self.data.scene.hydrology.lake_level;
         let mut drainage = self.data.scene.hydrology.drainage;
@@ -212,14 +240,58 @@ impl OpenVistaProApp {
         changed |= ui
             .add(egui::Slider::new(&mut drainage, 0.0..=5.0).text("Drainage"))
             .changed();
+        ui.label("Lake placement");
+        let mut lake_center_x = self.data.scene.hydrology.lake_center_x;
+        let mut lake_center_z = self.data.scene.hydrology.lake_center_z;
+        let mut lake_radius = self.data.scene.hydrology.lake_radius;
+        ui.horizontal(|ui| {
+            ui.label("Center X/Z");
+            changed |= ui
+                .add(
+                    egui::DragValue::new(&mut lake_center_x)
+                        .speed(0.01)
+                        .range(0.0..=1.0),
+                )
+                .changed();
+            changed |= ui
+                .add(
+                    egui::DragValue::new(&mut lake_center_z)
+                        .speed(0.01)
+                        .range(0.0..=1.0),
+                )
+                .changed();
+        });
+        changed |= ui
+            .add(egui::Slider::new(&mut lake_radius, 0.0..=0.5).text("Radius"))
+            .changed();
+        ui.label("River placement");
+        let mut river_center_x = self.data.scene.hydrology.river_center_x;
+        let mut river_width = self.data.scene.hydrology.river_width;
+        let mut river_bend = self.data.scene.hydrology.river_bend;
+        changed |= ui
+            .add(egui::Slider::new(&mut river_center_x, 0.0..=1.0).text("Center X"))
+            .changed();
+        changed |= ui
+            .add(egui::Slider::new(&mut river_width, 0.0..=0.25).text("Width"))
+            .changed();
+        changed |= ui
+            .add(egui::Slider::new(&mut river_bend, 0.0..=0.35).text("Bend"))
+            .changed();
         self.data.apply(AppAction::SetHydrology {
             river_level,
             lake_level,
             drainage,
+            lake_center_x,
+            lake_center_z,
+            lake_radius,
+            river_center_x,
+            river_width,
+            river_bend,
         });
 
         ui.separator();
-        ui.label("Palette");
+        ui.label("Color map");
+        ui.label("Core elevation bands");
         let mut palette = self.data.scene.palette;
         ui.horizontal(|ui| {
             ui.label("Water");
@@ -389,9 +461,12 @@ impl OpenVistaProApp {
                 ui.separator();
                 ui.label(format!("Terrain: {:?}", self.data.terrain_preset));
                 ui.label(format!("Renderer: {:?}", self.data.renderer_mode));
+                ui.label(format!("Quality: {:?}", self.data.render_quality));
                 let (width, height) = self.data.preview_size;
                 ui.label(format!("Preview: {width} x {height}"));
                 ui.label(format!("Water level: {:.2}", self.data.scene.water_level));
+                ui.label(format!("Tree line: {:.2}", self.data.scene.tree_line));
+                ui.label(format!("Snow line: {:.2}", self.data.scene.snow_line));
             });
     }
 
@@ -476,6 +551,29 @@ fn vec3_controls(ui: &mut egui::Ui, label: &str, value: &mut Vec3) -> bool {
     changed
 }
 
+fn orientation_controls(ui: &mut egui::Ui, value: &mut Vec3) -> bool {
+    let mut changed = false;
+    ui.horizontal(|ui| {
+        ui.label("Heading / yaw");
+        changed |= ui
+            .add(egui::DragValue::new(&mut value.x).speed(0.25).suffix("°"))
+            .changed();
+    });
+    ui.horizontal(|ui| {
+        ui.label("Pitch");
+        changed |= ui
+            .add(egui::DragValue::new(&mut value.y).speed(0.25).suffix("°"))
+            .changed();
+    });
+    ui.horizontal(|ui| {
+        ui.label("Bank / roll");
+        changed |= ui
+            .add(egui::DragValue::new(&mut value.z).speed(0.25).suffix("°"))
+            .changed();
+    });
+    changed
+}
+
 fn rgb_image_to_color_image(image: &RgbImage) -> egui::ColorImage {
     let size = [image.width() as usize, image.height() as usize];
     egui::ColorImage::from_rgb(size, image.as_raw())
diff --git a/src/app_state.rs b/src/app_state.rs
index 312e84e..5cefef4 100644
--- a/src/app_state.rs
+++ b/src/app_state.rs
@@ -3,7 +3,9 @@ use std::path::Path;
 use image::RgbImage;
 
 use crate::path::{CameraPath, build_demo_path};
-use crate::render::{render_perspective, render_top_down};
+use crate::render::{
+    RenderQualityPreset, render_perspective_with_quality, render_top_down_with_quality,
+};
 use crate::scene::{Scene, Vec3};
 use crate::scene_file::{self, SceneFileError};
 use crate::script::{Command, parse_script};
@@ -49,6 +51,32 @@ impl RendererMode {
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum RenderQuality {
+    Preview,
+    Balanced,
+    Final,
+}
+
+impl RenderQuality {
+    /// Human-readable label used by the UI shell and CLI.
+    pub fn label(self) -> &'static str {
+        match self {
+            RenderQuality::Preview => "Preview",
+            RenderQuality::Balanced => "Balanced",
+            RenderQuality::Final => "Final",
+        }
+    }
+
+    pub fn preset(self) -> RenderQualityPreset {
+        match self {
+            RenderQuality::Preview => RenderQualityPreset::Preview,
+            RenderQuality::Balanced => RenderQualityPreset::Balanced,
+            RenderQuality::Final => RenderQualityPreset::Final,
+        }
+    }
+}
+
 /// A pure, derived summary of a parsed script, suitable for display in the UI.
 ///
 /// All counts are zero and `error` carries the parser message when the script
@@ -124,6 +152,7 @@ pub struct AppData {
     pub scene: Scene,
     pub terrain_preset: TerrainPreset,
     pub renderer_mode: RendererMode,
+    pub render_quality: RenderQuality,
     pub preview_size: (u32, u32),
     pub loaded_scene_path: Option<String>,
     /// Heightmap path selected for import.
@@ -150,6 +179,7 @@ impl Default for AppData {
             scene: Scene::default(),
             terrain_preset: TerrainPreset::RadialHill,
             renderer_mode: RendererMode::TopDown,
+            render_quality: RenderQuality::Preview,
             preview_size: (256, 256),
             loaded_scene_path: Some(scene_path),
             import_path: Some(import_path.clone()),
@@ -169,6 +199,7 @@ impl AppData {
         match action {
             AppAction::SetTerrainPreset(preset) => self.terrain_preset = preset,
             AppAction::SetRendererMode(mode) => self.renderer_mode = mode,
+            AppAction::SetRenderQuality(quality) => self.render_quality = quality,
             AppAction::SetWaterLevel(value) => self.scene.water_level = value,
             AppAction::SetTreeLine(value) => self.scene.tree_line = value,
             AppAction::SetSnowLine(value) => self.scene.snow_line = value,
@@ -194,10 +225,25 @@ impl AppData {
                 river_level,
                 lake_level,
                 drainage,
+                lake_center_x,
+                lake_center_z,
+                lake_radius,
+                river_center_x,
+                river_width,
+                river_bend,
             } => {
                 self.scene.hydrology.river_level = river_level;
                 self.scene.hydrology.lake_level = lake_level;
                 self.scene.hydrology.drainage = drainage.max(0.0);
+                self.scene.hydrology.lake_center_x = lake_center_x.clamp(0.0, 1.0);
+                self.scene.hydrology.lake_center_z = lake_center_z.clamp(0.0, 1.0);
+                self.scene.hydrology.lake_radius = lake_radius.max(0.0);
+                self.scene.hydrology.river_center_x = river_center_x.clamp(0.0, 1.0);
+                self.scene.hydrology.river_width = river_width.max(0.0);
+                self.scene.hydrology.river_bend = river_bend.clamp(0.0, 0.5);
+            }
+            AppAction::ResetHydrology => {
+                self.scene.hydrology = crate::scene::Hydrology::default();
             }
             AppAction::SetPalette(palette) => self.scene.palette = palette,
             AppAction::SetPreviewSize { width, height } => {
@@ -215,6 +261,7 @@ impl AppData {
         self.last_script_run = None;
         self.terrain_preset = TerrainPreset::RadialHill;
         self.renderer_mode = RendererMode::TopDown;
+        self.render_quality = RenderQuality::Preview;
     }
 
     pub fn open_scene(&mut self, path: &Path) -> Result<(), SceneFileError> {
@@ -280,17 +327,18 @@ impl AppData {
             import_label: "Import terrain".to_string(),
             script_label: "Scripts / paths".to_string(),
             path_label: "Path tools".to_string(),
-            scene_controls_label: "Scene / camera / palette".to_string(),
-            palette_label: "Palette / color map".to_string(),
+            scene_controls_label: "Scene / camera / color map".to_string(),
+            palette_label: "Color map".to_string(),
             hydrology_label: "Hydrology".to_string(),
             legacy_dialogs_label: "Legacy dialogs".to_string(),
             scene_file_path: self.loaded_scene_path.clone(),
             import_path: self.import_path.clone(),
             path_target: self.path_target.clone(),
             status_line: format!(
-                "CPU preview · {} · {} · exag {:.2} · {width}×{height}",
+                "CPU preview · {} · {} · {} · exag {:.2} · {width}×{height}",
                 self.terrain_preset.label(),
                 self.renderer_mode.label(),
+                self.render_quality.label(),
                 self.scene.vertical_exaggeration,
             ),
             script_preview: ScriptPreview::from_source(&self.script_source),
@@ -305,8 +353,16 @@ impl AppData {
         let grid = self.build_preview_grid()?;
         let (width, height) = self.preview_size;
         let image = match self.renderer_mode {
-            RendererMode::TopDown => render_top_down(&grid, &self.scene),
-            RendererMode::Perspective => render_perspective(&grid, &self.scene, width, height),
+            RendererMode::TopDown => {
+                render_top_down_with_quality(&grid, &self.scene, self.render_quality.preset())
+            }
+            RendererMode::Perspective => render_perspective_with_quality(
+                &grid,
+                &self.scene,
+                width,
+                height,
+                self.render_quality.preset(),
+            ),
         };
         Ok(image)
     }
@@ -316,6 +372,7 @@ impl AppData {
 pub enum AppAction {
     SetTerrainPreset(TerrainPreset),
     SetRendererMode(RendererMode),
+    SetRenderQuality(RenderQuality),
     SetWaterLevel(f32),
     SetTreeLine(f32),
     SetSnowLine(f32),
@@ -333,7 +390,14 @@ pub enum AppAction {
         river_level: f32,
         lake_level: f32,
         drainage: f32,
+        lake_center_x: f32,
+        lake_center_z: f32,
+        lake_radius: f32,
+        river_center_x: f32,
+        river_width: f32,
+        river_bend: f32,
     },
+    ResetHydrology,
     SetPalette(crate::scene::Palette),
     SetPreviewSize {
         width: u32,
@@ -377,6 +441,35 @@ mod tests {
         assert_eq!(app.scene.camera, original_camera);
     }
 
+    #[test]
+    fn reducer_updates_hydrology_shapes_and_reset() {
+        let mut app = AppData::default();
+        app.apply(AppAction::SetHydrology {
+            river_level: 0.25,
+            lake_level: 0.5,
+            drainage: 0.1,
+            lake_center_x: 1.3,
+            lake_center_z: -0.2,
+            lake_radius: 0.3,
+            river_center_x: -0.4,
+            river_width: 0.12,
+            river_bend: 0.9,
+        });
+
+        assert_eq!(app.scene.hydrology.river_level, 0.25);
+        assert_eq!(app.scene.hydrology.lake_level, 0.5);
+        assert_eq!(app.scene.hydrology.drainage, 0.1);
+        assert_eq!(app.scene.hydrology.lake_center_x, 1.0);
+        assert_eq!(app.scene.hydrology.lake_center_z, 0.0);
+        assert_eq!(app.scene.hydrology.lake_radius, 0.3);
+        assert_eq!(app.scene.hydrology.river_center_x, 0.0);
+        assert_eq!(app.scene.hydrology.river_width, 0.12);
+        assert_eq!(app.scene.hydrology.river_bend, 0.5);
+
+        app.apply(AppAction::ResetHydrology);
+        assert_eq!(app.scene.hydrology, crate::scene::Hydrology::default());
+    }
+
     #[test]
     fn reducer_updates_camera_vectors_and_mode() {
         let mut app = AppData::default();
@@ -415,6 +508,21 @@ mod tests {
         assert_eq!(preview.height(), 64);
     }
 
+    #[test]
+    fn render_quality_changes_preview_output() {
+        let mut app = AppData::default();
+        app.apply(AppAction::SetPreviewSize {
+            width: 33,
+            height: 33,
+        });
+
+        let preview = app.render_preview().unwrap();
+        app.apply(AppAction::SetRenderQuality(RenderQuality::Final));
+        let final_img = app.render_preview().unwrap();
+
+        assert_ne!(preview.as_raw(), final_img.as_raw());
+    }
+
     #[test]
     fn ui_snapshot_exposes_existing_controls_and_new_entry_points() {
         let app = AppData::default();
@@ -426,10 +534,12 @@ mod tests {
         assert_eq!(shell.import_label, "Import terrain");
         assert_eq!(shell.script_label, "Scripts / paths");
         assert_eq!(shell.path_label, "Path tools");
+        assert_eq!(shell.palette_label, "Color map");
         assert!(shell.scene_file_path.is_some());
         assert!(shell.import_path.is_some());
         assert!(shell.path_target.is_none());
         assert!(shell.status_line.contains("CPU preview"));
+        assert!(shell.status_line.contains("Preview"));
     }
 
     #[test]
diff --git a/src/cli.rs b/src/cli.rs
index ccb6884..149423d 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -3,8 +3,13 @@ use std::path::PathBuf;
 use clap::{Args, Parser, Subcommand, ValueEnum};
 use image::ImageError;
 
-use crate::render::{demo_camera_for, render_perspective_to_path, render_top_down_to_path};
+use crate::render::{
+    RenderQualityPreset, demo_camera_for, render_perspective_with_quality,
+    render_top_down_with_quality,
+};
+
 use crate::scene::Scene;
+
 use crate::scene_file::{self, SceneFileError};
 use crate::script_exec::{self, ScriptError};
 use crate::terrain::{HeightGrid, TerrainError};
@@ -55,6 +60,9 @@ pub struct RenderArgs {
     /// the top-down preview.
     #[arg(long, default_value_t = false)]
     pub camera_demo: bool,
+    /// Render-quality preset for the CPU spike.
+    #[arg(long, value_enum, default_value_t = RenderQualityPreset::Preview)]
+    pub quality: RenderQualityPreset,
 }
 
 #[derive(Debug, Clone, Args)]
@@ -146,10 +154,39 @@ impl From<ScriptError> for CliError {
     }
 }
 
+impl Preset {
+    pub fn slug(self) -> &'static str {
+        match self {
+            Preset::Plane => "plane",
+            Preset::Hill => "hill",
+        }
+    }
+}
+
 pub fn supported_presets() -> &'static [&'static str] {
     &["plane", "hill"]
 }
 
+pub fn supported_quality_presets() -> &'static [&'static str] {
+    &["preview", "balanced", "final"]
+}
+
+pub fn resolve_render_output_path(
+    output: &std::path::Path,
+    preset: Preset,
+    quality: RenderQualityPreset,
+) -> PathBuf {
+    if output.is_dir() {
+        output.join(format!(
+            "openvistapro-{}-{}.png",
+            preset.slug(),
+            quality.output_tag()
+        ))
+    } else {
+        output.to_path_buf()
+    }
+}
+
 pub fn supported_importers() -> &'static [&'static str] {
     #[cfg(all(
         feature = "hgt",
@@ -223,6 +260,12 @@ pub fn info_text() -> String {
     let mut text = String::new();
     writeln!(&mut text, "openvistapro {}", env!("CARGO_PKG_VERSION")).unwrap();
     writeln!(&mut text, "presets: {}", supported_presets().join(", ")).unwrap();
+    writeln!(
+        &mut text,
+        "quality presets: {}",
+        supported_quality_presets().join(", ")
+    )
+    .unwrap();
     let importers = supported_importers();
     if importers.is_empty() {
         writeln!(&mut text, "importers: (none)").unwrap();
@@ -244,6 +287,7 @@ pub fn execute(cli: Cli) -> Result<(), CliError> {
                 Preset::Plane => HeightGrid::plane(args.width, args.height)?,
                 Preset::Hill => HeightGrid::radial_hill(args.width, args.height, HILL_PEAK_HEIGHT)?,
             };
+            let output = resolve_render_output_path(&args.output, args.preset, args.quality);
             let mut scene = if let Some(path) = args.scene.as_deref() {
                 scene_file::load_from_path(path)?
             } else {
@@ -251,15 +295,23 @@ pub fn execute(cli: Cli) -> Result<(), CliError> {
             };
             if args.camera_demo {
                 scene.camera = demo_camera_for(&grid);
-                render_perspective_to_path(&grid, &scene, args.width, args.height, &args.output)?;
+                let image = render_perspective_with_quality(
+                    &grid,
+                    &scene,
+                    args.width,
+                    args.height,
+                    args.quality,
+                );
+                image.save(&output)?;
             } else {
-                render_top_down_to_path(&grid, &scene, &args.output)?;
+                let image = render_top_down_with_quality(&grid, &scene, args.quality);
+                image.save(&output)?;
             }
             Ok(())
         }
         Command::Scene(args) => match args.action {
             SceneAction::Export(export) => {
-                scene_file::save_to_path(&Scene::default(), &export.output)?;
+                scene_file::save_to_path(&crate::scene::Scene::default(), &export.output)?;
                 Ok(())
             }
         },
@@ -278,6 +330,7 @@ pub fn execute(cli: Cli) -> Result<(), CliError> {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use crate::scene::Scene;
 
     #[test]
     fn parses_info_command() {
@@ -707,6 +760,12 @@ mod tests {
             water_level: 1000.0,
             tree_line: 1001.0,
             snow_line: 1002.0,
+            hydrology: crate::scene::Hydrology {
+                lake_radius: 0.0,
+                river_width: 0.0,
+                river_bend: 0.0,
+                ..crate::scene::Hydrology::default()
+            },
             ..Scene::default()
         };
         crate::scene_file::save_to_path(&custom, &scene_path).expect("save scene");
diff --git a/src/colormap.rs b/src/colormap.rs
index d209439..4344570 100644
--- a/src/colormap.rs
+++ b/src/colormap.rs
@@ -195,4 +195,13 @@ mod tests {
         );
         assert_eq!(scene_color(&scene, scene.snow_line + 1.0), SNOW_COLOR);
     }
+
+    #[test]
+    fn scene_color_uses_palette_band_colors_for_the_default_scene() {
+        let scene = Scene::default();
+        assert_eq!(scene.palette.water, WATER_COLOR);
+        assert_eq!(scene.palette.lowland, LOWLAND_COLOR);
+        assert_eq!(scene.palette.highland, HIGHLAND_COLOR);
+        assert_eq!(scene.palette.snow, SNOW_COLOR);
+    }
 }
diff --git a/src/render.rs b/src/render.rs
index 4b8e3c5..faf7a2b 100644
--- a/src/render.rs
+++ b/src/render.rs
@@ -1,11 +1,60 @@
 use std::path::Path;
 
+use clap::ValueEnum;
 use image::{ImageError, Rgb, RgbImage};
 
 use crate::colormap::scene_color;
 use crate::scene::{Camera, Scene, Vec3};
 use crate::terrain::HeightGrid;
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, ValueEnum)]
+pub enum RenderQualityPreset {
+    Preview,
+    Balanced,
+    Final,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub struct RenderQualityProfile {
+    pub label: &'static str,
+    pub output_tag: &'static str,
+    pub perspective_step: f32,
+    pub top_down_blur_passes: u8,
+}
+
+impl RenderQualityPreset {
+    pub fn profile(self) -> RenderQualityProfile {
+        match self {
+            RenderQualityPreset::Preview => RenderQualityProfile {
+                label: "Preview",
+                output_tag: "preview",
+                perspective_step: 0.70,
+                top_down_blur_passes: 0,
+            },
+            RenderQualityPreset::Balanced => RenderQualityProfile {
+                label: "Balanced",
+                output_tag: "balanced",
+                perspective_step: 0.45,
+                top_down_blur_passes: 1,
+            },
+            RenderQualityPreset::Final => RenderQualityProfile {
+                label: "Final",
+                output_tag: "final",
+                perspective_step: 0.25,
+                top_down_blur_passes: 2,
+            },
+        }
+    }
+
+    pub fn label(self) -> &'static str {
+        self.profile().label
+    }
+
+    pub fn output_tag(self) -> &'static str {
+        self.profile().output_tag
+    }
+}
+
 pub fn render_top_down(grid: &HeightGrid, scene: &Scene) -> RgbImage {
     let w = grid.width();
     let h = grid.height();
@@ -14,13 +63,64 @@ pub fn render_top_down(grid: &HeightGrid, scene: &Scene) -> RgbImage {
     for y in 0..h {
         for x in 0..w {
             let elevation = grid.sample(x, y).unwrap_or(0.0) * vertical_exaggeration;
-            let color = scene_color(scene, elevation);
+            let (nx, nz) = normalized_coords(x, y, w, h);
+            let color = surface_color(scene, elevation, nx, nz);
             img.put_pixel(x, y, Rgb(color));
         }
     }
     img
 }
 
+fn blur_pass(image: &RgbImage) -> RgbImage {
+    let mut blurred = RgbImage::new(image.width(), image.height());
+    for y in 0..image.height() {
+        for x in 0..image.width() {
+            let mut accum = [0u32; 3];
+            let mut count = 0u32;
+            for dy in -1i32..=1 {
+                for dx in -1i32..=1 {
+                    let nx = x as i32 + dx;
+                    let ny = y as i32 + dy;
+                    if nx < 0 || ny < 0 {
+                        continue;
+                    }
+                    let (nx, ny) = (nx as u32, ny as u32);
+                    if nx >= image.width() || ny >= image.height() {
+                        continue;
+                    }
+                    let px = image.get_pixel(nx, ny).0;
+                    accum[0] += u32::from(px[0]);
+                    accum[1] += u32::from(px[1]);
+                    accum[2] += u32::from(px[2]);
+                    count += 1;
+                }
+            }
+            let avg = [
+                (accum[0] / count.max(1)) as u8,
+                (accum[1] / count.max(1)) as u8,
+                (accum[2] / count.max(1)) as u8,
+            ];
+            blurred.put_pixel(x, y, Rgb(avg));
+        }
+    }
+    blurred
+}
+
+fn apply_top_down_quality(mut image: RgbImage, quality: RenderQualityPreset) -> RgbImage {
+    for _ in 0..quality.profile().top_down_blur_passes {
+        image = blur_pass(&image);
+    }
+    image
+}
+
+pub fn render_top_down_with_quality(
+    grid: &HeightGrid,
+    scene: &Scene,
+    quality: RenderQualityPreset,
+) -> RgbImage {
+    apply_top_down_quality(render_top_down(grid, scene), quality)
+}
+
 pub fn render_top_down_to_path(
     grid: &HeightGrid,
     scene: &Scene,
@@ -55,6 +155,53 @@ fn mix_color(color: [u8; 3], target: [u8; 3], factor: f32) -> [u8; 3] {
     ]
 }
 
+fn normalized_coords(x: u32, y: u32, width: u32, height: u32) -> (f32, f32) {
+    let nx = if width > 1 {
+        x as f32 / (width as f32 - 1.0)
+    } else {
+        0.5
+    };
+    let nz = if height > 1 {
+        y as f32 / (height as f32 - 1.0)
+    } else {
+        0.5
+    };
+    (nx.clamp(0.0, 1.0), nz.clamp(0.0, 1.0))
+}
+
+fn hydrology_overlay_color(scene: &Scene, nx: f32, nz: f32) -> Option<[u8; 3]> {
+    let lake = scene.hydrology.lake_coverage(nx, nz);
+    let river = scene.hydrology.river_coverage(nx, nz);
+    let coverage = lake.max(river);
+    if coverage <= 0.0 {
+        return None;
+    }
+
+    let tint = if lake >= river {
+        mix_color(scene.palette.water, [40, 125, 225], 0.68)
+    } else {
+        mix_color(scene.palette.water, [100, 210, 255], 0.75)
+    };
+    let colored = mix_color(scene.palette.water, tint, coverage);
+    Some(if coverage > 0.72 {
+        mix_color(
+            colored,
+            [245, 250, 255],
+            (coverage - 0.72).clamp(0.0, 0.28) * 3.0,
+        )
+    } else {
+        colored
+    })
+}
+
+fn surface_color(scene: &Scene, elevation: f32, nx: f32, nz: f32) -> [u8; 3] {
+    let base = scene_color(scene, elevation);
+    match hydrology_overlay_color(scene, nx, nz) {
+        Some(overlay) => mix_color(base, overlay, 0.9),
+        None => base,
+    }
+}
+
 fn v_add(a: Vec3, b: Vec3) -> Vec3 {
     Vec3::new(a.x + b.x, a.y + b.y, a.z + b.z)
 }
@@ -178,6 +325,16 @@ pub fn demo_camera_for(grid: &HeightGrid) -> Camera {
 /// Coordinate convention: world X and Z map onto the grid's `(x, y)` indices,
 /// world Y is elevation, up = +Y.
 pub fn render_perspective(grid: &HeightGrid, scene: &Scene, width: u32, height: u32) -> RgbImage {
+    render_perspective_with_quality(grid, scene, width, height, RenderQualityPreset::Preview)
+}
+
+pub fn render_perspective_with_quality(
+    grid: &HeightGrid,
+    scene: &Scene,
+    width: u32,
+    height: u32,
+    quality: RenderQualityPreset,
+) -> RgbImage {
     let mut img = RgbImage::new(width.max(1), height.max(1));
 
     let cam = &scene.camera;
@@ -196,7 +353,7 @@ pub fn render_perspective(grid: &HeightGrid, scene: &Scene, width: u32, height:
     let grid_w = grid.width() as f32;
     let grid_h = grid.height() as f32;
     let max_dist = cam.far_range.max(cam.near_range + 0.1);
-    let step = 0.5_f32;
+    let step = quality.profile().perspective_step;
 
     let haze_strength = scene.haze.clamp(0.0, 1.0);
 
@@ -220,7 +377,17 @@ pub fn render_perspective(grid: &HeightGrid, scene: &Scene, width: u32, height:
                 if let Some(terrain_h) = sample_height_bilinear(grid, p.x, p.z) {
                     let terrain_h = terrain_height(scene, terrain_h);
                     if p.y <= terrain_h {
-                        let band = scene_color(scene, terrain_h);
+                        let nx = if grid_w > 1.0 {
+                            (p.x / (grid_w - 1.0)).clamp(0.0, 1.0)
+                        } else {
+                            0.5
+                        };
+                        let nz = if grid_h > 1.0 {
+                            (p.z / (grid_h - 1.0)).clamp(0.0, 1.0)
+                        } else {
+                            0.5
+                        };
+                        let band = surface_color(scene, terrain_h, nx, nz);
                         let distance_fade = (t / max_dist).clamp(0.0, 1.0);
                         let fade = distance_fade * haze_strength;
                         hit_color = Some(mix_color(band, sky, fade));
@@ -253,11 +420,23 @@ pub fn render_perspective_to_path(
 mod tests {
     use super::*;
     use crate::colormap::{HIGHLAND_COLOR, LOWLAND_COLOR, SNOW_COLOR, WATER_COLOR};
+    use crate::scene::{Hydrology, Scene};
 
     fn fixture_scene() -> Scene {
         Scene::default()
     }
 
+    fn dry_scene() -> Scene {
+        Scene {
+            hydrology: Hydrology {
+                lake_radius: 0.0,
+                river_width: 0.0,
+                ..Hydrology::default()
+            },
+            ..Scene::default()
+        }
+    }
+
     #[test]
     fn render_matches_grid_dimensions() {
         let grid = HeightGrid::plane(8, 5).unwrap();
@@ -267,19 +446,27 @@ mod tests {
     }
 
     #[test]
-    fn render_plane_is_uniform_water() {
-        let grid = HeightGrid::plane(4, 4).unwrap();
+    fn render_plane_shows_distinct_hydrology_overlays() {
+        let grid = HeightGrid::plane(32, 32).unwrap();
         let img = render_top_down(&grid, &fixture_scene());
+
+        let mut saw_base_water = false;
+        let mut saw_feature = false;
         for y in 0..img.height() {
             for x in 0..img.width() {
-                let p = img.get_pixel(x, y);
-                assert_eq!(p.0, WATER_COLOR, "pixel at ({x},{y}) should be water");
+                match img.get_pixel(x, y).0 {
+                    c if c == WATER_COLOR => saw_base_water = true,
+                    c if c != WATER_COLOR => saw_feature = true,
+                    _ => unreachable!(),
+                }
             }
         }
+        assert!(saw_base_water, "expected background water pixels");
+        assert!(saw_feature, "expected lake/river overlay pixels");
     }
 
     #[test]
-    fn render_hill_has_all_four_bands() {
+    fn render_hill_has_all_four_bands_and_hydrology_overlays() {
         let grid = HeightGrid::radial_hill(33, 33, 10.0).unwrap();
         let img = render_top_down(&grid, &fixture_scene());
 
@@ -287,6 +474,7 @@ mod tests {
         let mut saw_lowland = false;
         let mut saw_highland = false;
         let mut saw_snow = false;
+        let mut saw_overlay = false;
         for y in 0..img.height() {
             for x in 0..img.width() {
                 match img.get_pixel(x, y).0 {
@@ -294,7 +482,7 @@ mod tests {
                     c if c == LOWLAND_COLOR => saw_lowland = true,
                     c if c == HIGHLAND_COLOR => saw_highland = true,
                     c if c == SNOW_COLOR => saw_snow = true,
-                    other => panic!("unexpected color {other:?} at ({x},{y})"),
+                    _ => saw_overlay = true,
                 }
             }
         }
@@ -302,15 +490,33 @@ mod tests {
         assert!(saw_lowland, "expected at least one lowland pixel");
         assert!(saw_highland, "expected at least one highland pixel");
         assert!(saw_snow, "expected at least one snow pixel");
+        assert!(saw_overlay, "expected lake/river overlay pixels");
     }
 
     #[test]
     fn render_center_of_hill_is_snow() {
         let grid = HeightGrid::radial_hill(5, 5, 10.0).unwrap();
-        let img = render_top_down(&grid, &fixture_scene());
+        let img = render_top_down(&grid, &dry_scene());
         assert_eq!(img.get_pixel(2, 2).0, SNOW_COLOR);
     }
 
+    #[test]
+    fn render_top_down_applies_vertical_exaggeration() {
+        let grid = HeightGrid::new(1, 1, vec![3.0]).unwrap();
+        let low_scene = dry_scene();
+        let high_scene = Scene {
+            vertical_exaggeration: 2.0,
+            ..dry_scene()
+        };
+
+        let low_img = render_top_down(&grid, &low_scene);
+        let high_img = render_top_down(&grid, &high_scene);
+
+        assert_eq!(low_img.get_pixel(0, 0).0, LOWLAND_COLOR);
+        assert_eq!(high_img.get_pixel(0, 0).0, HIGHLAND_COLOR);
+        assert_ne!(low_img.as_raw(), high_img.as_raw());
+    }
+
     #[test]
     fn render_is_deterministic() {
         let grid = HeightGrid::radial_hill(16, 16, 10.0).unwrap();
@@ -320,6 +526,30 @@ mod tests {
         assert_eq!(a.as_raw(), b.as_raw());
     }
 
+    #[test]
+    fn render_quality_presets_change_sampling_and_blur() {
+        let preview = RenderQualityPreset::Preview.profile();
+        let balanced = RenderQualityPreset::Balanced.profile();
+        let final_profile = RenderQualityPreset::Final.profile();
+
+        assert_eq!(preview.label, "Preview");
+        assert_eq!(preview.top_down_blur_passes, 0);
+        assert!(preview.perspective_step > balanced.perspective_step);
+        assert!(balanced.perspective_step > final_profile.perspective_step);
+        assert!(balanced.top_down_blur_passes > preview.top_down_blur_passes);
+        assert!(final_profile.top_down_blur_passes > balanced.top_down_blur_passes);
+    }
+
+    #[test]
+    fn render_top_down_quality_changes_output_for_detail_presets() {
+        let grid = HeightGrid::radial_hill(33, 33, 10.0).unwrap();
+        let scene = fixture_scene();
+        let preview = render_top_down_with_quality(&grid, &scene, RenderQualityPreset::Preview);
+        let final_img = render_top_down_with_quality(&grid, &scene, RenderQualityPreset::Final);
+
+        assert_ne!(preview.as_raw(), final_img.as_raw());
+    }
+
     #[test]
     fn render_to_path_writes_png_file() {
         let grid = HeightGrid::radial_hill(8, 8, 10.0).unwrap();
@@ -428,6 +658,25 @@ mod tests {
         let _img = render_perspective(&plane, &demo_scene(&plane), 16, 16);
     }
 
+    #[test]
+    fn render_perspective_applies_vertical_exaggeration() {
+        let grid = HeightGrid::radial_hill(32, 32, 10.0).unwrap();
+        let low_scene = demo_scene(&grid);
+        let high_scene = Scene {
+            vertical_exaggeration: 2.0,
+            ..demo_scene(&grid)
+        };
+
+        let low_img = render_perspective(&grid, &low_scene, 32, 32);
+        let high_img = render_perspective(&grid, &high_scene, 32, 32);
+
+        assert_ne!(
+            low_img.as_raw(),
+            high_img.as_raw(),
+            "vertical exaggeration should alter perspective output"
+        );
+    }
+
     #[test]
     fn render_perspective_to_path_writes_png_file() {
         let grid = HeightGrid::radial_hill(16, 16, 10.0).unwrap();
diff --git a/src/scene.rs b/src/scene.rs
index 058fc9a..7ecf823 100644
--- a/src/scene.rs
+++ b/src/scene.rs
@@ -24,10 +24,13 @@ impl Vec3 {
 pub struct Camera {
     pub position: Vec3,
     pub target: Vec3,
-    /// Heading, pitch, and bank in degrees.
+    /// Camera heading (yaw), pitch, and bank/roll in degrees.
     pub orientation: Vec3,
+    /// Vertical field of view in degrees used by the pinhole camera.
     pub fov_degrees: f32,
+    /// Near clipping distance in world units from the camera.
     pub near_range: f32,
+    /// Far clipping distance in world units from the camera.
     pub far_range: f32,
 }
 
@@ -63,6 +66,9 @@ impl Default for Light {
 #[derive(Debug, Clone, Copy, PartialEq, Serialize, Deserialize)]
 #[serde(default)]
 pub struct Palette {
+    pub water_level: f32,
+    pub tree_line: f32,
+    pub snow_line: f32,
     pub water: [u8; 3],
     pub lowland: [u8; 3],
     pub highland: [u8; 3],
@@ -72,6 +78,9 @@ pub struct Palette {
 impl Default for Palette {
     fn default() -> Self {
         Self {
+            water_level: 1.0,
+            tree_line: 4.0,
+            snow_line: 7.0,
             water: [30, 70, 130],
             lowland: [70, 130, 50],
             highland: [120, 100, 80],
@@ -80,18 +89,72 @@ impl Default for Palette {
     }
 }
 
+impl Palette {
+    pub fn sync_thresholds_from_scene(&mut self, water_level: f32, tree_line: f32, snow_line: f32) {
+        self.water_level = water_level;
+        self.tree_line = tree_line;
+        self.snow_line = snow_line;
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Serialize, Deserialize)]
 #[serde(default)]
 pub struct Hydrology {
     pub river_level: f32,
     pub lake_level: f32,
     pub drainage: f32,
+    /// Normalized center point for the generated lake overlay.
+    pub lake_center_x: f32,
+    /// Normalized center point for the generated lake overlay.
+    pub lake_center_z: f32,
+    /// Normalized radius for the generated lake overlay.
+    pub lake_radius: f32,
+    /// Normalized centerline for the generated river overlay.
+    pub river_center_x: f32,
+    /// Normalized half-width for the generated river overlay.
+    pub river_width: f32,
+    /// Horizontal meander amplitude for the generated river overlay.
+    pub river_bend: f32,
+}
+
+fn smoothstep(edge0: f32, edge1: f32, value: f32) -> f32 {
+    if edge0 >= edge1 {
+        return if value < edge0 { 0.0 } else { 1.0 };
+    }
+    let t = ((value - edge0) / (edge1 - edge0)).clamp(0.0, 1.0);
+    t * t * (3.0 - 2.0 * t)
 }
 
 impl Hydrology {
     pub fn effective_water_level(self, base_water_level: f32) -> f32 {
         (base_water_level.max(self.river_level).max(self.lake_level) - self.drainage).max(0.0)
     }
+
+    /// Coverage of the generated lake primitive at normalized coordinates.
+    pub fn lake_coverage(self, x: f32, z: f32) -> f32 {
+        let radius = self.lake_radius.max(0.0);
+        if radius <= 0.0 {
+            return 0.0;
+        }
+        let dx = x - self.lake_center_x;
+        let dz = z - self.lake_center_z;
+        let dist = (dx * dx + dz * dz).sqrt();
+        let falloff = (radius * 0.2).max(0.01);
+        1.0 - smoothstep(radius - falloff, radius + falloff, dist)
+    }
+
+    /// Coverage of the generated river primitive at normalized coordinates.
+    pub fn river_coverage(self, x: f32, z: f32) -> f32 {
+        let half_width = self.river_width.max(0.0);
+        if half_width <= 0.0 {
+            return 0.0;
+        }
+        let meander = self.river_bend * (z * std::f32::consts::TAU * 1.25).sin();
+        let center_x = (self.river_center_x + meander).clamp(0.0, 1.0);
+        let dist = (x - center_x).abs();
+        let falloff = (half_width * 0.35).max(0.01);
+        1.0 - smoothstep(half_width - falloff, half_width + falloff, dist)
+    }
 }
 
 impl Default for Hydrology {
@@ -100,6 +163,12 @@ impl Default for Hydrology {
             river_level: 0.5,
             lake_level: 0.75,
             drainage: 0.0,
+            lake_center_x: 0.38,
+            lake_center_z: 0.62,
+            lake_radius: 0.16,
+            river_center_x: 0.58,
+            river_width: 0.08,
+            river_bend: 0.08,
         }
     }
 }
@@ -188,4 +257,26 @@ mod tests {
         assert_eq!(s.camera, Camera::default());
         assert_eq!(s.light, Light::default());
     }
+
+    #[test]
+    fn hydrology_default_generates_distinct_lake_and_river_shapes() {
+        let h = Hydrology::default();
+        assert!(h.lake_radius > 0.0);
+        assert!(h.river_width > 0.0);
+        assert!(h.lake_coverage(h.lake_center_x, h.lake_center_z) > 0.9);
+        assert!(h.river_coverage(h.river_center_x, 0.5) > 0.5);
+        assert!(h.lake_coverage(0.0, 0.0) < 0.2);
+    }
+
+    #[test]
+    fn hydrology_clamps_and_falls_off_with_distance() {
+        let h = Hydrology {
+            river_bend: 0.0,
+            ..Hydrology::default()
+        };
+        let center = h.lake_coverage(h.lake_center_x, h.lake_center_z);
+        let far = h.lake_coverage(0.95, 0.05);
+        assert!(center > far);
+        assert!(h.river_coverage(h.river_center_x, 0.5) > h.river_coverage(0.0, 0.5));
+    }
 }
diff --git a/src/scene_file.rs b/src/scene_file.rs
index 8ada155..8e9bfdf 100644
--- a/src/scene_file.rs
+++ b/src/scene_file.rs
@@ -88,7 +88,11 @@ impl From<toml::de::Error> for SceneFileError {
 
 /// Serialize `scene` into a TOML string with schema and version headers.
 pub fn to_toml_string(scene: &Scene) -> Result<String, SceneFileError> {
-    let file = SceneFile::new(*scene);
+    let mut scene = *scene;
+    scene
+        .palette
+        .sync_thresholds_from_scene(scene.water_level, scene.tree_line, scene.snow_line);
+    let file = SceneFile::new(scene);
     Ok(toml::to_string_pretty(&file)?)
 }
 
@@ -101,7 +105,11 @@ pub fn from_toml_str(text: &str) -> Result<Scene, SceneFileError> {
     if file.version != SCENE_VERSION {
         return Err(SceneFileError::UnsupportedVersion(file.version));
     }
-    Ok(file.scene)
+    let mut scene = file.scene;
+    scene
+        .palette
+        .sync_thresholds_from_scene(scene.water_level, scene.tree_line, scene.snow_line);
+    Ok(scene)
 }
 
 /// Write `scene` to `path` as an OpenVistaPro `.ovp.toml` scene file.
@@ -150,8 +158,17 @@ mod tests {
                 river_level: 0.8,
                 lake_level: 1.1,
                 drainage: 0.2,
+                lake_center_x: 0.42,
+                lake_center_z: 0.58,
+                lake_radius: 0.11,
+                river_center_x: 0.6,
+                river_width: 0.09,
+                river_bend: 0.04,
             },
             palette: Palette {
+                water_level: 0.5,
+                tree_line: 3.0,
+                snow_line: 8.0,
                 water: [12, 34, 56],
                 lowland: [78, 90, 12],
                 highland: [123, 111, 99],
diff --git a/src/script_exec.rs b/src/script_exec.rs
index 0a70c20..f245bbe 100644
--- a/src/script_exec.rs
+++ b/src/script_exec.rs
@@ -141,6 +141,11 @@ pub fn run_script(script: &Script, base_dir: &Path) -> Result<ExecReport, Script
                 scene.water_level = thresholds.water;
                 scene.tree_line = thresholds.tree;
                 scene.snow_line = thresholds.snow;
+                scene.palette.sync_thresholds_from_scene(
+                    thresholds.water,
+                    thresholds.tree,
+                    thresholds.snow,
+                );
             }
             Command::ImportHeightmap { path } => {
                 grid = Some(load_heightmap(&resolve(base_dir, path))?);