docs: document plan generation constraints feature

DOCUMENTATION.md

@@ -86,6 +86,12 @@ classDiagram
         +Graph ReferenceGraph
     }
 
+    class PlanGenerationConstraints {
+        +Polygon BoundingPolygon
+        +Vector2? FrontDoorFacing
+        +Vector2? GarageFacing
+    }
+
     class Graph {
         +Dictionary Nodes
         +List~Edge~ Edges
@@ -121,6 +127,10 @@ classDiagram
     *   `Geometries`: A dictionary mapping category names (e.g., "living", "wall", "door") to lists of NetTopologySuite `Geometry` objects.
     *   `Bounds`: The spatial bounding box of the plan.
     *   `ReferenceGraph`: The ground-truth graph provided by the dataset (if available).
+*   **`PlanGenerationConstraints`**: Configuration for filtering and orienting loaded plans.
+    *   `BoundingPolygon`: A polygon that must fully contain the plan's bounds.
+    *   `FrontDoorFacing`: A target vector for the front door's orientation relative to the plan's center.
+    *   `GarageFacing`: *Unsupported in current dataset*.
 *   **`Graph`**: Represents the connectivity graph of the floorplan.
     *   Generated by `GraphGenerator` or loaded as `ReferenceGraph`.
 *   **`Node`**: A node in the graph, typically representing a room or a portal (door/window).
@@ -135,11 +145,15 @@ classDiagram
 
 Handles the loading of plan data.
 
-*   `static Task<List<Plan>> LoadPlansAsync(string jsonPath = null, string pklPathOverride = null, int? maxItems = null, Action<string> logger = null)`
+*   `static Task<List<Plan>> LoadPlansAsync(string jsonPath = null, string pklPathOverride = null, int? maxItems = null, Action<string> logger = null, PlanGenerationConstraints constraints = null)`
     *   **jsonPath**: Optional path to a pre-converted JSON file. If provided, skips Python execution.
     *   **pklPathOverride**: Optional path to a specific `.pkl` file. If null, defaults to the managed dataset path.
     *   **maxItems**: Optional limit on the number of plans to load.
     *   **logger**: Optional callback to receive real-time progress updates (e.g., dependency installation logs, download progress).
+    *   **constraints**: Optional `PlanGenerationConstraints` to filter or orient plans.
+        *   **BoundingPolygon**: If set, only plans whose bounds are completely contained within this polygon are returned.
+        *   **FrontDoorFacing**: If set, plans are rotated so their front door (vector from center to door) aligns with this vector.
+        *   **GarageFacing**: Currently unsupported; will log a warning if set.
     *   **Returns**: A list of `Plan` objects.
 
 ### `ResPlan.Library.Data.PlanSerializer`

README.md

@@ -43,7 +43,43 @@ var plans = await PlanLoader.LoadPlansAsync(
 Console.WriteLine($"Loaded {plans.Count} plans.");
 ```
 
-### 2. Generating Connectivity Graphs
+### 2. Applying Constraints (Optional)
+
+You can filter and orient plans using `PlanGenerationConstraints`.
+
+```csharp
+using NetTopologySuite.Geometries;
+using System.Numerics;
+
+// Define a bounding box polygon (must contain the plan)
+var coordinates = new[]
+{
+    new Coordinate(0, 0),
+    new Coordinate(100, 0),
+    new Coordinate(100, 100),
+    new Coordinate(0, 100),
+    new Coordinate(0, 0) // Close the loop
+};
+var boundingPoly = new GeometryFactory().CreatePolygon(coordinates);
+
+// Define constraints
+var constraints = new PlanGenerationConstraints
+{
+    // Filter: Plan must fit inside this polygon
+    BoundingPolygon = boundingPoly,
+
+    // Orientation: Rotate plan so the front door faces "Up" (positive Y)
+    FrontDoorFacing = new Vector2(0, 1)
+};
+
+var constrainedPlans = await PlanLoader.LoadPlansAsync(
+    maxItems: 5,
+    logger: logger,
+    constraints: constraints
+);
+```
+
+### 3. Generating Connectivity Graphs
 
 Once a `Plan` is loaded, you can generate a graph representing the connectivity between rooms, doors, and windows using `GraphGenerator`.
 
@@ -67,7 +103,7 @@ foreach (var plan in plans)
 }
 ```
 
-### 3. Rendering Floorplans
+### 4. Rendering Floorplans
 
 You can visualize the floorplan using `PlanRenderer`. This uses SkiaSharp to produce an image file.
 
@@ -85,7 +121,7 @@ foreach (var plan in plans)
 }
 ```
 
-### 4. Serialization
+### 5. Serialization
 
 To support binary serialization and handle special floating-point values (like `NaN` or `Infinity`) which are not standard in JSON, the library provides a helper class `PlanSerializer` using **MessagePack**.