changed version number

Cargo.lock

@@ -116,7 +116,7 @@ checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
 
 [[package]]
 name = "advanced_erosion_terrain_heightmap_generation"
-version = "0.1.0"
+version = "0.2.0"
 dependencies = [
  "arboard",
  "eframe",
@@ -124,6 +124,7 @@ dependencies = [
  "image",
  "rand",
  "rayon",
+ "rfd",
 ]
 
 [[package]]
@@ -461,6 +462,15 @@ dependencies = [
  "objc2 0.5.2",
 ]
 
+[[package]]
+name = "block2"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cdeb9d870516001442e364c5220d3574d2da8dc765554b4a617230d33fa58ef5"
+dependencies = [
+ "objc2 0.6.4",
+]
+
 [[package]]
 name = "blocking"
 version = "1.6.2"
@@ -755,6 +765,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1e0e367e4e7da84520dedcac1901e4da967309406d1e51017ae1abfb97adbd38"
 dependencies = [
  "bitflags 2.11.1",
+ "block2 0.6.2",
+ "libc",
  "objc2 0.6.4",
 ]
 
@@ -1536,10 +1548,23 @@ checksum = "85ab80394333c02fe689eaf900ab500fbd0c2213da414687ebf995a65d5a6104"
 dependencies = [
  "bytemuck",
  "byteorder-lite",
+ "image-webp",
  "moxcms",
  "num-traits",
  "png",
  "tiff",
+ "zune-core",
+ "zune-jpeg",
+]
+
+[[package]]
+name = "image-webp"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "525e9ff3e1a4be2fbea1fdf0e98686a6d98b4d8f937e1bf7402245af1909e8c3"
+dependencies = [
+ "byteorder-lite",
+ "quick-error",
 ]
 
 [[package]]
@@ -1939,7 +1964,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e4e89ad9e3d7d297152b17d39ed92cd50ca8063a89a9fa569046d41568891eff"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "libc",
  "objc2 0.5.2",
  "objc2-core-data",
@@ -1955,6 +1980,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d49e936b501e5c5bf01fda3a9452ff86dc3ea98ad5f283e1455153142d97518c"
 dependencies = [
  "bitflags 2.11.1",
+ "block2 0.6.2",
  "objc2 0.6.4",
  "objc2-core-foundation",
  "objc2-core-graphics",
@@ -1968,7 +1994,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "74dd3b56391c7a0596a295029734d3c1c5e7e510a4cb30245f8221ccea96b009"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-core-location",
  "objc2-foundation 0.2.2",
@@ -1980,7 +2006,7 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a5ff520e9c33812fd374d8deecef01d4a840e7b41862d849513de77e44aa4889"
 dependencies = [
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-foundation 0.2.2",
 ]
@@ -1992,7 +2018,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "617fbf49e071c178c0b24c080767db52958f716d9eabdf0890523aeae54773ef"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-foundation 0.2.2",
 ]
@@ -2027,7 +2053,7 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "55260963a527c99f1819c4f8e3b47fe04f9650694ef348ffd2227e8196d34c80"
 dependencies = [
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-foundation 0.2.2",
  "objc2-metal",
@@ -2039,7 +2065,7 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "000cfee34e683244f284252ee206a27953279d370e309649dc3ee317b37e5781"
 dependencies = [
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-contacts",
  "objc2-foundation 0.2.2",
@@ -2058,7 +2084,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0ee638a5da3799329310ad4cfa62fbf045d5f56e3ef5ba4149e7452dcf89d5a8"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "dispatch",
  "libc",
  "objc2 0.5.2",
@@ -2092,7 +2118,7 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a1a1ae721c5e35be65f01a03b6d2ac13a54cb4fa70d8a5da293d7b0020261398"
 dependencies = [
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-app-kit 0.2.2",
  "objc2-foundation 0.2.2",
@@ -2105,7 +2131,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dd0cba1276f6023976a406a14ffa85e1fdd19df6b0f737b063b95f6c8c7aadd6"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-foundation 0.2.2",
 ]
@@ -2117,7 +2143,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e42bee7bff906b14b167da2bac5efe6b6a07e6f7c0a21a7308d40c960242dc7a"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-foundation 0.2.2",
  "objc2-metal",
@@ -2140,7 +2166,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b8bb46798b20cd6b91cbd113524c490f1686f4c4e8f49502431415f3512e2b6f"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-cloud-kit",
  "objc2-core-data",
@@ -2160,7 +2186,7 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "44fa5f9748dbfe1ca6c0b79ad20725a11eca7c2218bceb4b005cb1be26273bfe"
 dependencies = [
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-foundation 0.2.2",
 ]
@@ -2172,7 +2198,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "76cfcbf642358e8689af64cee815d139339f3ed8ad05103ed5eaf73db8d84cb3"
 dependencies = [
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "objc2 0.5.2",
  "objc2-core-location",
  "objc2-foundation 0.2.2",
@@ -2339,6 +2365,12 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "pollster"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2f3a9f18d041e6d0e102a0a46750538147e5e8992d3b4873aaafee2520b00ce3"
+
 [[package]]
 name = "portable-atomic"
 version = "1.13.1"
@@ -2558,6 +2590,33 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "19b30a45b0cd0bcca8037f3d0dc3421eaf95327a17cad11964fb8179b4fc4832"
 
+[[package]]
+name = "rfd"
+version = "0.17.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "20dafead71c16a34e1ff357ddefc8afc11e7d51d6d2b9fbd07eaa48e3e540220"
+dependencies = [
+ "block2 0.6.2",
+ "dispatch2",
+ "js-sys",
+ "libc",
+ "log",
+ "objc2 0.6.4",
+ "objc2-app-kit 0.3.2",
+ "objc2-core-foundation",
+ "objc2-foundation 0.3.2",
+ "percent-encoding",
+ "pollster",
+ "raw-window-handle",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "wayland-backend",
+ "wayland-client",
+ "wayland-protocols",
+ "web-sys",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "rustc-hash"
 version = "1.1.0"
@@ -3953,7 +4012,7 @@ dependencies = [
  "android-activity",
  "atomic-waker",
  "bitflags 2.11.1",
- "block2",
+ "block2 0.5.1",
  "bytemuck",
  "calloop 0.13.0",
  "cfg_aliases",

Cargo.toml

@@ -1,15 +1,16 @@
 [package]
 name = "advanced_erosion_terrain_heightmap_generation"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2024"
 
 [dependencies]
 arboard = "3.6"
 eframe = "0.33"
 egui = "0.33"
-image = { version = "0.25", default-features = false, features = ["png"] }
+image = { version = "0.25", default-features = false, features = ["jpeg", "png", "webp"] }
 rand = "0.9"
 rayon = "1.10"
+rfd = "0.17.2"
 
 [profile.release]
 opt-level = "z"

README.md

@@ -1,4 +1,4 @@
-# advanced_erosion_terrain_heightmap_generation
+# Grim Rune Terrain Generator
 
 A standalone Rust terrain generator using `egui`, using a terrain generation method by Runevision (Skovbo Johansen).
 
@@ -16,7 +16,7 @@ git clone https://codeberg.org/Grimsace/advanced_erosion_terrain_heightmap_gener
 cargo build --release
 ```
 
-## Running:
+## Easy Way:
 
 Download the latest release!
 

src/app.rs

@@ -18,12 +18,16 @@ enum LeftTab {
 
 #[derive(Copy, Clone, Eq, PartialEq)]
 enum PreviewFocus {
+    TerrainComposite,
+    TerrainColor,
     Heightmap,
     Bumpmap,
 }
 
 #[derive(Clone)]
-struct TexturePair {
+struct TextureSet {
+    terrain_composite: TextureHandle,
+    terrain_color: TextureHandle,
     heightmap: TextureHandle,
     bumpmap: TextureHandle,
 }
@@ -33,12 +37,14 @@ pub struct TerrainApp {
     generation_tab: LeftTab,
     preview_focus: PreviewFocus,
     hovered_preview: Option<PreviewFocus>,
-    textures: Option<TexturePair>,
+    textures: Option<TextureSet>,
     generated: Option<GeneratedImages>,
     generation_receiver: Option<Receiver<Result<GeneratedImages, String>>>,
     generation_in_progress: bool,
     copy_receiver: Option<Receiver<Result<String, String>>>,
     copy_in_progress: bool,
+    export_receiver: Option<Receiver<Result<String, String>>>,
+    export_in_progress: bool,
     status_message: String,
 }
 
@@ -47,7 +53,7 @@ impl TerrainApp {
         Self {
             params: GenerationParams::default(),
             generation_tab: LeftTab::Generation,
-            preview_focus: PreviewFocus::Bumpmap,
+            preview_focus: PreviewFocus::TerrainComposite,
             hovered_preview: None,
             textures: None,
             generated: None,
@@ -55,6 +61,8 @@ impl TerrainApp {
             generation_in_progress: false,
             copy_receiver: None,
             copy_in_progress: false,
+            export_receiver: None,
+            export_in_progress: false,
             status_message: String::from("Adjust parameters and click Generate."),
         }
     }
@@ -88,7 +96,7 @@ impl TerrainApp {
         match receiver.try_recv() {
             Ok(Ok(images)) => {
                 self.status_message = format!(
-                    "Generated {}x{} heightmap and bumpmap.",
+                    "Generated {}x{} heightmap, bumpmap, terrain color, and composite.",
                     images.width, images.height
                 );
                 self.install_textures(ctx, &images);
@@ -139,11 +147,173 @@ impl TerrainApp {
         }
     }
 
+    fn poll_export(&mut self, ctx: &Context) {
+        let Some(receiver) = &self.export_receiver else {
+            return;
+        };
+
+        match receiver.try_recv() {
+            Ok(Ok(message)) => {
+                self.status_message = message;
+                self.export_receiver = None;
+                self.export_in_progress = false;
+            }
+            Ok(Err(error)) => {
+                self.status_message = error;
+                self.export_receiver = None;
+                self.export_in_progress = false;
+            }
+            Err(TryRecvError::Empty) => {
+                ctx.request_repaint();
+            }
+            Err(TryRecvError::Disconnected) => {
+                self.status_message = String::from("Export worker disconnected.");
+                self.export_receiver = None;
+                self.export_in_progress = false;
+            }
+        }
+    }
+
+    fn start_export(&mut self, preview: PreviewFocus) {
+        if self.export_in_progress {
+            self.status_message = String::from("Export already in progress...");
+            return;
+        }
+
+        let Some(generated) = &self.generated else {
+            self.status_message = String::from("No generated image is available to export.");
+            return;
+        };
+
+        let label = preview_label(preview).to_lowercase().replace(' ', "_");
+        let default_name = format!("{}.png", label);
+
+        let files = rfd::FileDialog::new()
+            .add_filter("PNG Image", &["png"])
+            .add_filter("JPEG Image", &["jpg", "jpeg"])
+            .add_filter("WebP Image", &["webp"])
+            .set_file_name(default_name)
+            .save_file();
+
+        let Some(path) = files else {
+            return;
+        };
+
+        let generated = generated.clone();
+        let (tx, rx) = mpsc::channel();
+        self.export_receiver = Some(rx);
+        self.export_in_progress = true;
+        self.status_message = format!("Exporting to {}...", path.display());
+
+        thread::spawn(move || {
+            let result = (|| -> Result<String, String> {
+                let format = match path.extension().and_then(|s| s.to_str()) {
+                    Some("jpg") | Some("jpeg") => image::ImageFormat::Jpeg,
+                    Some("webp") => image::ImageFormat::WebP,
+                    _ => image::ImageFormat::Png,
+                };
+
+                match preview {
+                    PreviewFocus::TerrainComposite => generated
+                        .terrain_composite_image
+                        .save_with_format(&path, format),
+                    PreviewFocus::TerrainColor => generated
+                        .terrain_color_image
+                        .save_with_format(&path, format),
+                    PreviewFocus::Heightmap => {
+                        generated.heightmap_image.save_with_format(&path, format)
+                    }
+                    PreviewFocus::Bumpmap => {
+                        generated.bumpmap_image.save_with_format(&path, format)
+                    }
+                }
+                .map_err(|e| format!("Failed to save image: {}", e))?;
+
+                Ok(format!("Successfully exported to {}.", path.display()))
+            })();
+            let _ = tx.send(result);
+        });
+    }
+
+    fn start_batch_export(&mut self) {
+        if self.export_in_progress {
+            self.status_message = String::from("Export already in progress...");
+            return;
+        }
+
+        let Some(generated) = &self.generated else {
+            self.status_message = String::from("No generated images available to export.");
+            return;
+        };
+
+        let folder = rfd::FileDialog::new()
+            .set_title("Select Export Folder")
+            .pick_folder();
+        let Some(path) = folder else {
+            return;
+        };
+
+        let generated = generated.clone();
+        let (tx, rx) = mpsc::channel();
+        self.export_receiver = Some(rx);
+        self.export_in_progress = true;
+        self.status_message = format!("Exporting all layers to {}...", path.display());
+
+        thread::spawn(move || {
+            let result = (|| -> Result<String, String> {
+                let save = |img_rgba: Option<&image::RgbaImage>,
+                            img_gray: Option<&image::GrayImage>,
+                            name: &str| {
+                    let full_path = path.join(format!("{}.png", name));
+                    if let Some(img) = img_rgba {
+                        img.save(&full_path)
+                    } else if let Some(img) = img_gray {
+                        img.save(&full_path)
+                    } else {
+                        return Err(format!("No image data for {}", name));
+                    }
+                    .map_err(|e| format!("Failed to save {}: {}", name, e))
+                };
+
+                save(
+                    Some(&generated.terrain_composite_image),
+                    None,
+                    "terrain_composite",
+                )?;
+                save(Some(&generated.terrain_color_image), None, "terrain_color")?;
+                save(None, Some(&generated.heightmap_image), "heightmap")?;
+                save(None, Some(&generated.bumpmap_image), "bumpmap")?;
+                save(None, Some(&generated.grass_mask_image), "mask_grass")?;
+                save(None, Some(&generated.water_mask_image), "mask_water")?;
+                save(None, Some(&generated.rock_mask_image), "mask_rock")?;
+                save(None, Some(&generated.snow_mask_image), "mask_snow")?;
+
+                Ok(format!(
+                    "Successfully exported 8 layers to {}.",
+                    path.display()
+                ))
+            })();
+            let _ = tx.send(result);
+        });
+    }
+
     fn install_textures(&mut self, ctx: &Context, images: &GeneratedImages) {
         let heightmap = gray_to_color_image(&images.heightmap_image);
         let bumpmap = gray_to_color_image(&images.bumpmap_image);
+        let terrain_composite = rgba_to_color_image(&images.terrain_composite_image);
+        let terrain_color = rgba_to_color_image(&images.terrain_color_image);
 
-        self.textures = Some(TexturePair {
+        self.textures = Some(TextureSet {
+            terrain_composite: ctx.load_texture(
+                "terrain_composite_preview",
+                terrain_composite,
+                TextureOptions::default(),
+            ),
+            terrain_color: ctx.load_texture(
+                "terrain_color_preview",
+                terrain_color,
+                TextureOptions::default(),
+            ),
             heightmap: ctx.load_texture("heightmap_preview", heightmap, TextureOptions::default()),
             bumpmap: ctx.load_texture("bumpmap_preview", bumpmap, TextureOptions::default()),
         });
@@ -160,11 +330,12 @@ impl TerrainApp {
             return;
         };
 
-        let image = match preview {
+        let image = preview_image_data(generated, preview);
-            PreviewFocus::Heightmap => generated.heightmap_image.clone(),
-            PreviewFocus::Bumpmap => generated.bumpmap_image.clone(),
-        };
         let success_message = match preview {
+            PreviewFocus::TerrainComposite => {
+                String::from("Terrain composite copied to clipboard.")
+            }
+            PreviewFocus::TerrainColor => String::from("Terrain color copied to clipboard."),
             PreviewFocus::Heightmap => String::from("Heightmap copied to clipboard."),
             PreviewFocus::Bumpmap => String::from("Bumpmap copied to clipboard."),
         };
@@ -173,25 +344,34 @@ impl TerrainApp {
         self.copy_receiver = Some(rx);
         self.copy_in_progress = true;
         self.status_message = match preview {
+            PreviewFocus::TerrainComposite => {
+                String::from("Copying terrain composite to clipboard...")
+            }
+            PreviewFocus::TerrainColor => String::from("Copying terrain color to clipboard..."),
             PreviewFocus::Heightmap => String::from("Copying heightmap to clipboard..."),
             PreviewFocus::Bumpmap => String::from("Copying bumpmap to clipboard..."),
         };
 
         thread::spawn(move || {
-            let result = copy_gray_image_to_clipboard(&image).map(|_| success_message);
+            let result = copy_image_to_clipboard(&image).map(|_| success_message);
             let _ = tx.send(result);
         });
     }
 
-    fn preview_context_menu(response: &Response) -> bool {
+    fn preview_context_menu(response: &Response) -> (bool, bool) {
         let mut should_copy = false;
+        let mut should_export = false;
         response.context_menu(|ui| {
             if ui.button("Copy").clicked() {
                 should_copy = true;
                 ui.close();
             }
+            if ui.button("Export").clicked() {
+                should_export = true;
+                ui.close();
+            }
         });
-        should_copy
+        (should_copy, should_export)
     }
 
     fn overlay_copy_button(ui: &mut Ui, anchor_rect: egui::Rect, preview: PreviewFocus) -> bool {
@@ -231,6 +411,43 @@ impl TerrainApp {
         clicked
     }
 
+    fn overlay_export_button(ui: &mut Ui, anchor_rect: egui::Rect, preview: PreviewFocus) -> bool {
+        let button_size = Vec2::new(28.0, 28.0);
+        let button_rect = Align2::RIGHT_TOP
+            .align_size_within_rect(button_size, anchor_rect.shrink2(Vec2::new(8.0 + 32.0, 8.0)));
+        let response = ui.interact(
+            button_rect,
+            ui.make_persistent_id(("main_export_button", preview == PreviewFocus::Bumpmap)),
+            Sense::click(),
+        );
+
+        let fill = if response.hovered() {
+            Color32::from_rgba_premultiplied(70, 90, 120, 220)
+        } else {
+            Color32::from_rgba_premultiplied(40, 40, 40, 180)
+        };
+        ui.painter()
+            .rect_filled(button_rect, CornerRadius::same(6), fill);
+        ui.painter().rect_stroke(
+            button_rect,
+            CornerRadius::same(6),
+            Stroke::new(1.0, Color32::from_rgba_premultiplied(255, 255, 255, 60)),
+            StrokeKind::Outside,
+        );
+        ui.painter().text(
+            button_rect.center(),
+            Align2::CENTER_CENTER,
+            "📥",
+            FontId::proportional(14.0),
+            Color32::WHITE,
+        );
+
+        let clicked = response.clicked();
+        response.on_hover_text("Export");
+        let _ = preview;
+        clicked
+    }
+
     fn tab_button(ui: &mut Ui, current: &mut LeftTab, tab: LeftTab, label: &str) {
         let selected = *current == tab;
         if ui.selectable_label(selected, label).clicked() {
@@ -273,6 +490,17 @@ impl TerrainApp {
                     self.start_generation();
                 }
 
+                ui.add_space(8.0);
+                if ui
+                    .add_sized(
+                        [ui.available_width(), 32.0],
+                        egui::Button::new("Export All Layers"),
+                    )
+                    .clicked()
+                {
+                    self.start_batch_export();
+                }
+
                 if self.generation_in_progress {
                     ui.add_space(8.0);
                     ui.spinner();
@@ -281,6 +509,10 @@ impl TerrainApp {
                     ui.add_space(4.0);
                     ui.spinner();
                 }
+                if self.export_in_progress {
+                    ui.add_space(4.0);
+                    ui.spinner();
+                }
 
                 ui.add_space(8.0);
                 ui.label(&self.status_message);
@@ -342,10 +574,30 @@ impl TerrainApp {
             0.1,
         );
         labeled_int_slider(ui, "Octaves", &mut self.params.erosion_octaves, 1..=8);
+        labeled_int_slider(
+            ui,
+            "Snowline Height",
+            &mut self.params.snowline_height,
+            0..=255,
+        );
+        labeled_int_slider(
+            ui,
+            "Water Table Height",
+            &mut self.params.water_table_height,
+            0..=255,
+        );
+        labeled_float_slider(
+            ui,
+            "Rock Slope Angle",
+            &mut self.params.rock_slope_angle_degrees,
+            0.0..=89.0,
+            1.0,
+        );
     }
 
     fn ui_right_panel(&mut self, ctx: &Context) {
         let mut pending_copy = None;
+        let mut pending_export = None;
         let mut pending_focus = None;
         let mut pending_hover = None;
         let preview_focus = self.preview_focus;
@@ -357,6 +609,8 @@ impl TerrainApp {
                 });
                 return;
             };
+            let terrain_composite_texture = textures.terrain_composite.clone();
+            let terrain_color_texture = textures.terrain_color.clone();
             let heightmap_texture = textures.heightmap.clone();
             let bumpmap_texture = textures.bumpmap.clone();
 
@@ -365,6 +619,8 @@ impl TerrainApp {
             let main_height = (available.y - bottom_strip_height - 8.0).max(100.0);
 
             let main_texture = match preview_focus {
+                PreviewFocus::TerrainComposite => &terrain_composite_texture,
+                PreviewFocus::TerrainColor => &terrain_color_texture,
                 PreviewFocus::Heightmap => &heightmap_texture,
                 PreviewFocus::Bumpmap => &bumpmap_texture,
             };
@@ -374,51 +630,61 @@ impl TerrainApp {
             if main_response.hovered() {
                 pending_hover = Some(preview_focus);
             }
-            if Self::preview_context_menu(&main_response)
+
-                || Self::overlay_copy_button(ui, main_response.rect, preview_focus)
+            let (context_copy, context_export) = Self::preview_context_menu(&main_response);
-            {
+            if context_copy || Self::overlay_copy_button(ui, main_response.rect, preview_focus) {
                 pending_copy = Some(preview_focus);
             }
+            if context_export || Self::overlay_export_button(ui, main_response.rect, preview_focus)
+            {
+                pending_export = Some(preview_focus);
+            }
             ui.add_space(8.0);
 
-            let thumb_width = (available.x * 0.28).clamp(120.0, 240.0);
+            let thumb_width = (available.x * 0.26).clamp(120.0, 220.0);
             let panel_width = (thumb_width + 32.0).min(available.x);
-            let secondary_texture = match preview_focus {
+            let secondary_previews = secondary_previews(preview_focus);
-                PreviewFocus::Heightmap => &bumpmap_texture,
-                PreviewFocus::Bumpmap => &heightmap_texture,
-            };
-            let secondary_focus = match preview_focus {
-                PreviewFocus::Heightmap => PreviewFocus::Bumpmap,
-                PreviewFocus::Bumpmap => PreviewFocus::Heightmap,
-            };
-            let secondary_label = match secondary_focus {
-                PreviewFocus::Heightmap => "Heightmap",
-                PreviewFocus::Bumpmap => "Bumpmap",
-            };
 
             ui.horizontal_centered(|ui| {
-                Frame::group(ui.style()).show(ui, |ui| {
+                ui.horizontal(|ui| {
-                    ui.set_min_width(panel_width);
+                    for secondary_focus in secondary_previews {
-                    ui.set_max_width(panel_width);
+                        let secondary_texture = match secondary_focus {
-                    ui.vertical_centered(|ui| {
+                            PreviewFocus::TerrainComposite => &terrain_composite_texture,
-                        ui.label(RichText::new(secondary_label).strong());
+                            PreviewFocus::TerrainColor => &terrain_color_texture,
-                        ui.add_space(6.0);
+                            PreviewFocus::Heightmap => &heightmap_texture,
-                        let secondary_response = render_clickable_image(
+                            PreviewFocus::Bumpmap => &bumpmap_texture,
-                            ui,
+                        };
-                            secondary_texture,
+                        let secondary_label = preview_label(secondary_focus);
-                            Vec2::new(thumb_width, bottom_strip_height - 32.0),
+
-                            true,
+                        Frame::group(ui.style()).show(ui, |ui| {
-                        );
+                            ui.set_min_width(panel_width);
-                        if secondary_response.hovered() {
+                            ui.set_max_width(panel_width);
-                            pending_hover = Some(secondary_focus);
+                            ui.vertical_centered(|ui| {
-                        }
+                                ui.label(RichText::new(secondary_label).strong());
-                        if Self::preview_context_menu(&secondary_response) {
+                                ui.add_space(6.0);
-                            pending_copy = Some(secondary_focus);
+                                let secondary_response = render_clickable_image(
-                        }
+                                    ui,
-                        if secondary_response.clicked() {
+                                    secondary_texture,
-                            pending_focus = Some(secondary_focus);
+                                    Vec2::new(thumb_width, bottom_strip_height - 32.0),
-                        }
+                                    true,
-                    });
+                                );
+                                if secondary_response.hovered() {
+                                    pending_hover = Some(secondary_focus);
+                                }
+                                let (context_copy, context_export) =
+                                    Self::preview_context_menu(&secondary_response);
+                                if context_copy {
+                                    pending_copy = Some(secondary_focus);
+                                }
+                                if context_export {
+                                    pending_export = Some(secondary_focus);
+                                }
+                                if secondary_response.clicked() {
+                                    pending_focus = Some(secondary_focus);
+                                }
+                            });
+                        });
+                    }
                 });
             });
         });
@@ -426,6 +692,9 @@ impl TerrainApp {
         if let Some(preview) = pending_copy {
             self.copy_preview(preview);
         }
+        if let Some(preview) = pending_export {
+            self.start_export(preview);
+        }
         if let Some(preview) = pending_focus {
             self.preview_focus = preview;
         }
@@ -438,6 +707,7 @@ impl eframe::App for TerrainApp {
         self.hovered_preview = None;
         self.poll_generation(ctx);
         self.poll_copy(ctx);
+        self.poll_export(ctx);
         self.ui_left_panel(ctx);
         self.ui_right_panel(ctx);
 
@@ -473,23 +743,69 @@ fn gray_to_color_image(image: &image::GrayImage) -> ColorImage {
     ColorImage::new(size, pixels)
 }
 
-fn labeled_int_slider(
+fn rgba_to_color_image(image: &image::RgbaImage) -> ColorImage {
+    let size = [image.width() as usize, image.height() as usize];
+    let mut pixels = Vec::with_capacity(size[0] * size[1]);
+    for pixel in image.pixels() {
+        let [r, g, b, a] = pixel.0;
+        pixels.push(Color32::from_rgba_unmultiplied(r, g, b, a));
+    }
+    ColorImage::new(size, pixels)
+}
+
+fn preview_image_data(images: &GeneratedImages, preview: PreviewFocus) -> ImageData<'static> {
+    match preview {
+        PreviewFocus::TerrainComposite => {
+            rgba_image_to_clipboard_data(&images.terrain_composite_image)
+        }
+        PreviewFocus::TerrainColor => rgba_image_to_clipboard_data(&images.terrain_color_image),
+        PreviewFocus::Heightmap => gray_image_to_clipboard_data(&images.heightmap_image),
+        PreviewFocus::Bumpmap => gray_image_to_clipboard_data(&images.bumpmap_image),
+    }
+}
+
+fn preview_label(preview: PreviewFocus) -> &'static str {
+    match preview {
+        PreviewFocus::TerrainComposite => "Composite",
+        PreviewFocus::TerrainColor => "Terrain Color",
+        PreviewFocus::Heightmap => "Heightmap",
+        PreviewFocus::Bumpmap => "Bumpmap",
+    }
+}
+
+fn secondary_previews(preview: PreviewFocus) -> [PreviewFocus; 3] {
+    match preview {
+        PreviewFocus::TerrainComposite => [
+            PreviewFocus::TerrainColor,
+            PreviewFocus::Heightmap,
+            PreviewFocus::Bumpmap,
+        ],
+        PreviewFocus::TerrainColor => [
+            PreviewFocus::TerrainComposite,
+            PreviewFocus::Heightmap,
+            PreviewFocus::Bumpmap,
+        ],
+        PreviewFocus::Heightmap => [
+            PreviewFocus::TerrainComposite,
+            PreviewFocus::TerrainColor,
+            PreviewFocus::Bumpmap,
+        ],
+        PreviewFocus::Bumpmap => [
+            PreviewFocus::TerrainComposite,
+            PreviewFocus::TerrainColor,
+            PreviewFocus::Heightmap,
+        ],
+    }
+}
+
+fn labeled_int_slider<Num: egui::emath::Numeric>(
     ui: &mut Ui,
     label: &str,
-    value: &mut usize,
+    value: &mut Num,
-    range: std::ops::RangeInclusive<usize>,
+    range: std::ops::RangeInclusive<Num>,
 ) {
     ui.label(label);
-    let mut slider_value = *value as u32;
+    ui.add(Slider::new(value, range));
-    if ui
-        .add(Slider::new(
-            &mut slider_value,
-            *range.start() as u32..=*range.end() as u32,
-        ))
-        .changed()
-    {
-        *value = slider_value as usize;
-    }
 }
 
 fn labeled_float_slider(
@@ -534,19 +850,36 @@ fn render_clickable_image(
     response
 }
 
-fn copy_gray_image_to_clipboard(image: &image::GrayImage) -> Result<(), String> {
+fn gray_image_to_clipboard_data(image: &image::GrayImage) -> ImageData<'static> {
     let mut rgba = Vec::with_capacity((image.width() * image.height() * 4) as usize);
     for pixel in image.pixels() {
         let gray = pixel.0[0];
         rgba.extend_from_slice(&[gray, gray, gray, 255]);
     }
 
-    let data = ImageData {
+    ImageData {
         width: image.width() as usize,
         height: image.height() as usize,
         bytes: rgba.into(),
-    };
+    }
+}
 
+fn rgba_image_to_clipboard_data(image: &image::RgbaImage) -> ImageData<'static> {
+    let mut rgba = Vec::with_capacity((image.width() * image.height() * 4) as usize);
+    for pixel in image.pixels() {
+        rgba.extend_from_slice(&pixel.0);
+    }
+
+    ImageData {
+        width: image.width() as usize,
+        height: image.height() as usize,
+        bytes: rgba.into(),
+    }
+}
+
+fn copy_image_to_clipboard(image: &ImageData<'static>) -> Result<(), String> {
     let mut clipboard = Clipboard::new().map_err(|error| error.to_string())?;
-    clipboard.set_image(data).map_err(|error| error.to_string())
+    clipboard
+        .set_image(image.clone())
+        .map_err(|error| error.to_string())
 }

src/generator.rs

@@ -1,4 +1,4 @@
-use image::{GrayImage, Luma};
+use image::{GrayImage, Luma, Rgba, RgbaImage};
 use rayon::prelude::*;
 
 const TAU: f32 = 6.283_185_5;
@@ -21,6 +21,9 @@ pub struct GenerationParams {
     pub erosion_gully_weight: f32,
     pub erosion_detail: f32,
     pub erosion_octaves: usize,
+    pub snowline_height: u8,
+    pub water_table_height: u8,
+    pub rock_slope_angle_degrees: f32,
 }
 
 impl Default for GenerationParams {
@@ -35,6 +38,9 @@ impl Default for GenerationParams {
             erosion_gully_weight: 0.5,
             erosion_detail: 1.5,
             erosion_octaves: 5,
+            snowline_height: 220,
+            water_table_height: 0,
+            rock_slope_angle_degrees: 15.0,
         }
     }
 }
@@ -45,6 +51,16 @@ pub struct GeneratedImages {
     pub height: usize,
     pub heightmap_image: GrayImage,
     pub bumpmap_image: GrayImage,
+    pub terrain_color_image: RgbaImage,
+    pub terrain_composite_image: RgbaImage,
+    #[allow(dead_code)]
+    pub grass_mask_image: GrayImage,
+    #[allow(dead_code)]
+    pub water_mask_image: GrayImage,
+    #[allow(dead_code)]
+    pub rock_mask_image: GrayImage,
+    #[allow(dead_code)]
+    pub snow_mask_image: GrayImage,
 }
 
 #[derive(Copy, Clone, Debug, Default)]
@@ -123,6 +139,10 @@ fn clamp01(x: f32) -> f32 {
     clamp(x, 0.0, 1.0)
 }
 
+fn mix_u8(a: u8, b: u8, t: f32) -> u8 {
+    mix(a as f32, b as f32, clamp01(t)).round() as u8
+}
+
 fn hash22(p: Vec2, random_seed: u64) -> Vec2 {
     let scrambled_x = splitmix64(random_seed ^ 0x9E37_79B9_7F4A_7C15);
     let scrambled_y = splitmix64(random_seed ^ 0xBF58_476D_1CE4_E5B9);
@@ -192,7 +212,14 @@ fn noised(p: Vec2, random_seed: u64) -> (f32, Vec2) {
     (val, Vec2::new(deriv_x, deriv_y))
 }
 
-fn fractal_noise(p: Vec2, freq: f32, octaves: usize, lacunarity: f32, gain: f32, random_seed: u64) -> (f32, Vec2) {
+fn fractal_noise(
+    p: Vec2,
+    freq: f32,
+    octaves: usize,
+    lacunarity: f32,
+    gain: f32,
+    random_seed: u64,
+) -> (f32, Vec2) {
     let mut val = 0.0;
     let mut deriv = Vec2::default();
     let mut nf = freq;
@@ -207,7 +234,14 @@ fn fractal_noise(p: Vec2, freq: f32, octaves: usize, lacunarity: f32, gain: f32,
     (val, deriv)
 }
 
-fn phacelle_noise(p: Vec2, norm_dir: Vec2, freq: f32, offset: f32, normalization: f32, random_seed: u64) -> (Vec2, Vec2) {
+fn phacelle_noise(
+    p: Vec2,
+    norm_dir: Vec2,
+    freq: f32,
+    offset: f32,
+    normalization: f32,
+    random_seed: u64,
+) -> (Vec2, Vec2) {
     let side_dir = Vec2::new(-norm_dir.y, norm_dir.x) * (freq * TAU);
     let offset_tau = offset * TAU;
 
@@ -241,7 +275,10 @@ fn phacelle_noise(p: Vec2, norm_dir: Vec2, freq: f32, offset: f32, normalization
     }
 
     let interpolated = phase_dir * (1.0 / weight_sum);
-    let magnitude = interpolated.dot(interpolated).sqrt().max(1.0 - normalization);
+    let magnitude = interpolated
+        .dot(interpolated)
+        .sqrt()
+        .max(1.0 - normalization);
     (interpolated * (1.0 / magnitude), side_dir)
 }
 
@@ -274,10 +311,8 @@ pub fn generate(params: &GenerationParams) -> GeneratedImages {
         .enumerate()
         .for_each(|(y, row)| {
             for (x, value) in row.iter_mut().enumerate() {
-                let p = Vec2::new(
+                let p = Vec2::new(x as f32 / width as f32, y as f32 / height as f32)
-                    x as f32 / width as f32,
+                    * params.generation_scale;
-                    y as f32 / height as f32,
-                ) * params.generation_scale;
 
                 let height_freq = 3.0;
                 let height_amp = 0.125;
@@ -369,15 +404,43 @@ pub fn generate(params: &GenerationParams) -> GeneratedImages {
     let bumpmap = apply_shading(&heightmap, width, height, 0.5);
     let heightmap_image = grayscale_image_from_values(&heightmap_normalized, width, height);
     let bumpmap_image = grayscale_image_from_values(&bumpmap, width, height);
+    let terrain_layers = build_terrain_layers(
+        &heightmap_normalized,
+        width,
+        height,
+        params.snowline_height,
+        params.water_table_height,
+        params.rock_slope_angle_degrees,
+    );
+    let terrain_composite_image = build_soft_light_composite(
+        &terrain_layers.terrain_color_image,
+        &bumpmap_image,
+        &heightmap_image,
+        &terrain_layers.water_mask_image,
+    );
 
     GeneratedImages {
         width,
         height,
         heightmap_image,
         bumpmap_image,
+        terrain_color_image: terrain_layers.terrain_color_image,
+        terrain_composite_image,
+        grass_mask_image: terrain_layers.grass_mask_image,
+        water_mask_image: terrain_layers.water_mask_image,
+        rock_mask_image: terrain_layers.rock_mask_image,
+        snow_mask_image: terrain_layers.snow_mask_image,
     }
 }
 
+struct TerrainLayers {
+    terrain_color_image: RgbaImage,
+    grass_mask_image: GrayImage,
+    water_mask_image: GrayImage,
+    rock_mask_image: GrayImage,
+    snow_mask_image: GrayImage,
+}
+
 fn normalize_values(values: &[f32]) -> Vec<f32> {
     let mut min_val = f32::INFINITY;
     let mut max_val = f32::NEG_INFINITY;
@@ -407,6 +470,162 @@ fn grayscale_image_from_values(values: &[f32], width: usize, height: usize) -> G
     image
 }
 
+fn build_terrain_layers(
+    heightmap: &[f32],
+    width: usize,
+    height: usize,
+    snowline_height: u8,
+    water_table_height: u8,
+    rock_slope_angle_degrees: f32,
+) -> TerrainLayers {
+    let mut terrain_color_image = RgbaImage::new(width as u32, height as u32);
+    let mut grass_mask_image = GrayImage::new(width as u32, height as u32);
+    let mut water_mask_image = GrayImage::new(width as u32, height as u32);
+    let mut rock_mask_image = GrayImage::new(width as u32, height as u32);
+    let mut snow_mask_image = GrayImage::new(width as u32, height as u32);
+
+    let low_grass_color = [78, 146, 64];
+    let high_grass_color = [150, 156, 88];
+    let water_color = Rgba([40, 70, 150, 255]);
+    let sand_color = [210, 195, 145];
+    let rock_color = Rgba([122, 112, 98, 255]);
+    let snow_color = Rgba([255, 250, 250, 255]);
+    let slope_threshold_radians = rock_slope_angle_degrees.clamp(0.0, 89.9).to_radians();
+
+    for y in 0..height {
+        for x in 0..width {
+            let idx = y * width + x;
+            let height_value = heightmap[idx].clamp(0.0, 1.0);
+            let u8_height = (height_value * 255.0).round() as u8;
+
+            let left = sample_height(heightmap, width, height, x.saturating_sub(1), y);
+            let right = sample_height(heightmap, width, height, (x + 1).min(width - 1), y);
+            let up = sample_height(heightmap, width, height, x, y.saturating_sub(1));
+            let down = sample_height(heightmap, width, height, x, (y + 1).min(height - 1));
+
+            let dx = (right - left) * 0.5 * width as f32;
+            let dy = (down - up) * 0.5 * height as f32;
+            let slope_angle = dx.hypot(dy).atan();
+
+            let grass_t = clamp01((height_value - 0.08) / 0.52);
+            let grass_color = [
+                mix_u8(low_grass_color[0], high_grass_color[0], grass_t),
+                mix_u8(low_grass_color[1], high_grass_color[1], grass_t),
+                mix_u8(low_grass_color[2], high_grass_color[2], grass_t),
+            ];
+            let is_water = if water_table_height == 0 {
+                false
+            } else {
+                u8_height < water_table_height
+            };
+
+            let sand_width = 4.0;
+            let sand_t = if water_table_height == 0 || is_water {
+                0.0
+            } else {
+                let diff = (u8_height - water_table_height) as f32;
+                (1.0 - (diff / sand_width)).clamp(0.0, 1.0)
+            };
+
+            let base_color = Rgba([
+                mix_u8(grass_color[0], sand_color[0], sand_t),
+                mix_u8(grass_color[1], sand_color[1], sand_t),
+                mix_u8(grass_color[2], sand_color[2], sand_t),
+                255,
+            ]);
+
+            let is_snow = if snowline_height == 0 {
+                true
+            } else if snowline_height == u8::MAX {
+                false
+            } else {
+                u8_height > snowline_height
+            };
+            let is_rock = slope_angle >= slope_threshold_radians;
+
+            grass_mask_image.put_pixel(x as u32, y as u32, Luma([255]));
+            water_mask_image.put_pixel(x as u32, y as u32, Luma([if is_water { 255 } else { 0 }]));
+            rock_mask_image.put_pixel(x as u32, y as u32, Luma([if is_rock { 255 } else { 0 }]));
+            snow_mask_image.put_pixel(x as u32, y as u32, Luma([if is_snow { 255 } else { 0 }]));
+
+            let color = if is_water {
+                water_color
+            } else if is_snow {
+                snow_color
+            } else if is_rock {
+                rock_color
+            } else {
+                base_color
+            };
+
+            terrain_color_image.put_pixel(x as u32, y as u32, color);
+        }
+    }
+
+    TerrainLayers {
+        terrain_color_image,
+        grass_mask_image,
+        water_mask_image,
+        rock_mask_image,
+        snow_mask_image,
+    }
+}
+
+fn build_soft_light_composite(
+    color_image: &RgbaImage,
+    bumpmap_image: &GrayImage,
+    heightmap_image: &GrayImage,
+    water_mask_image: &GrayImage,
+) -> RgbaImage {
+    let mut composite = RgbaImage::new(color_image.width(), color_image.height());
+
+    for y in 0..color_image.height() {
+        for x in 0..color_image.width() {
+            let base = color_image.get_pixel(x, y).0;
+            let is_water = water_mask_image.get_pixel(x, y).0[0] > 0;
+
+            let blend = if is_water {
+                heightmap_image.get_pixel(x, y).0[0] as f32 / 255.0
+            } else {
+                bumpmap_image.get_pixel(x, y).0[0] as f32 / 255.0
+            };
+
+            let r = soft_light_channel(base[0] as f32 / 255.0, blend);
+            let g = soft_light_channel(base[1] as f32 / 255.0, blend);
+            let b = soft_light_channel(base[2] as f32 / 255.0, blend);
+
+            composite.put_pixel(
+                x,
+                y,
+                Rgba([
+                    (r * 255.0).round() as u8,
+                    (g * 255.0).round() as u8,
+                    (b * 255.0).round() as u8,
+                    base[3],
+                ]),
+            );
+        }
+    }
+
+    composite
+}
+
+fn soft_light_channel(base: f32, blend: f32) -> f32 {
+    let base = clamp01(base);
+    let blend = clamp01(blend);
+    let result = if blend <= 0.5 {
+        base - (1.0 - 2.0 * blend) * base * (1.0 - base)
+    } else {
+        let d = if base <= 0.25 {
+            ((16.0 * base - 12.0) * base + 4.0) * base
+        } else {
+            base.sqrt()
+        };
+        base + (2.0 * blend - 1.0) * (d - base)
+    };
+    clamp01(result)
+}
+
 fn apply_shading(heightmap: &[f32], width: usize, height: usize, strength: f32) -> Vec<f32> {
     let mut output = vec![0.0; width * height];