classref: Sync with current master branch (215acd5)

classes/class_trianglemesh.rst

@@ -12,14 +12,117 @@ TriangleMesh
 
 **Inherits:** :ref:`RefCounted<class_RefCounted>` **<** :ref:`Object<class_Object>`
 
-Internal mesh type.
+Triangle geometry for efficient, physicsless intersection queries.
 
 .. rst-class:: classref-introduction-group
 
 Description
 -----------
 
-Mesh type used internally for collision calculations.
+Creates a bounding volume hierarchy (BVH) tree structure around triangle geometry.
+
+The triangle BVH tree can be used for efficient intersection queries without involving a physics engine.
+
+For example, this can be used in editor tools to select objects with complex shapes based on the mouse cursor position.
+
+\ **Performance:** Creating the BVH tree for complex geometry is a slow process and best done in a background thread.
+
+.. rst-class:: classref-reftable-group
+
+Methods
+-------
+
+.. table::
+   :widths: auto
+
+   +-----------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+
+   | :ref:`bool<class_bool>`                             | :ref:`create_from_faces<class_TriangleMesh_method_create_from_faces>`\ (\ faces\: :ref:`PackedVector3Array<class_PackedVector3Array>`\ )                        |
+   +-----------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+
+   | :ref:`PackedVector3Array<class_PackedVector3Array>` | :ref:`get_faces<class_TriangleMesh_method_get_faces>`\ (\ ) |const|                                                                                             |
+   +-----------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+
+   | :ref:`Dictionary<class_Dictionary>`                 | :ref:`intersect_ray<class_TriangleMesh_method_intersect_ray>`\ (\ begin\: :ref:`Vector3<class_Vector3>`, dir\: :ref:`Vector3<class_Vector3>`\ ) |const|         |
+   +-----------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+
+   | :ref:`Dictionary<class_Dictionary>`                 | :ref:`intersect_segment<class_TriangleMesh_method_intersect_segment>`\ (\ begin\: :ref:`Vector3<class_Vector3>`, end\: :ref:`Vector3<class_Vector3>`\ ) |const| |
+   +-----------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+
+
+.. rst-class:: classref-section-separator
+
+----
+
+.. rst-class:: classref-descriptions-group
+
+Method Descriptions
+-------------------
+
+.. _class_TriangleMesh_method_create_from_faces:
+
+.. rst-class:: classref-method
+
+:ref:`bool<class_bool>` **create_from_faces**\ (\ faces\: :ref:`PackedVector3Array<class_PackedVector3Array>`\ ) :ref:`🔗<class_TriangleMesh_method_create_from_faces>`
+
+Creates the BVH tree from an array of faces. Each 3 vertices of the input ``faces`` array represent one triangle (face).
+
+Returns ``true`` if the tree is successfully built, ``false`` otherwise.
+
+.. rst-class:: classref-item-separator
+
+----
+
+.. _class_TriangleMesh_method_get_faces:
+
+.. rst-class:: classref-method
+
+:ref:`PackedVector3Array<class_PackedVector3Array>` **get_faces**\ (\ ) |const| :ref:`🔗<class_TriangleMesh_method_get_faces>`
+
+Returns a copy of the geometry faces. Each 3 vertices of the array represent one triangle (face).
+
+.. rst-class:: classref-item-separator
+
+----
+
+.. _class_TriangleMesh_method_intersect_ray:
+
+.. rst-class:: classref-method
+
+:ref:`Dictionary<class_Dictionary>` **intersect_ray**\ (\ begin\: :ref:`Vector3<class_Vector3>`, dir\: :ref:`Vector3<class_Vector3>`\ ) |const| :ref:`🔗<class_TriangleMesh_method_intersect_ray>`
+
+Tests for intersection with a ray starting at ``begin`` and facing ``dir`` and extending toward infinity.
+
+If an intersection with a triangle happens, returns a :ref:`Dictionary<class_Dictionary>` with the following fields:
+
+\ ``position``: The position on the intersected triangle.
+
+\ ``normal``: The normal of the intersected triangle.
+
+\ ``face_index``: The index of the intersected triangle.
+
+Returns an empty :ref:`Dictionary<class_Dictionary>` if no intersection happens.
+
+See also :ref:`intersect_segment()<class_TriangleMesh_method_intersect_segment>`, which is similar but uses a finite-length segment.
+
+.. rst-class:: classref-item-separator
+
+----
+
+.. _class_TriangleMesh_method_intersect_segment:
+
+.. rst-class:: classref-method
+
+:ref:`Dictionary<class_Dictionary>` **intersect_segment**\ (\ begin\: :ref:`Vector3<class_Vector3>`, end\: :ref:`Vector3<class_Vector3>`\ ) |const| :ref:`🔗<class_TriangleMesh_method_intersect_segment>`
+
+Tests for intersection with a segment going from ``begin`` to ``end``.
+
+If an intersection with a triangle happens returns a :ref:`Dictionary<class_Dictionary>` with the following fields:
+
+\ ``position``: The position on the intersected triangle.
+
+\ ``normal``: The normal of the intersected triangle.
+
+\ ``face_index``: The index of the intersected triangle.
+
+Returns an empty :ref:`Dictionary<class_Dictionary>` if no intersection happens.
+
+See also :ref:`intersect_ray()<class_TriangleMesh_method_intersect_ray>`, which is similar but uses an infinite-length ray.
 
 .. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`
 .. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`