***** Scene ***** The **Scene** tab in :doc:`Properties Editor ` exposes options related to the current scene. Physics ======= .. figure:: /images/editors-properties-scene-physics.png Scene tab's Physics panel. The *Physics* panel located in the *Scene* tab determine the type of physical rules that govern the current UPBGE scene, the gravity value to be used and some other options. Physics Engine Set the type of physics engine to use. Bullet The default physics engine, in active development. It handles movement and collision detection. The things that collide transfer momentum to the collided object. None No physics in use. Things are not affected by gravity and can fly about in a virtual space. Objects in motion stay in that motion. Physics Solver The physics constraints solver to use. Sequential Sequential physics solver, default solver. NNGC NNGC physics solver. MLCP Dantzig MLCP Dantzig physics solver. MLCP Lemke MLCP Lemke physics solver. Gravity The gravitational acceleration, m.s\ :sup:`-2` (in units of meters per squared second), of this world. Each object that is an actor has a mass and size slider. In conjunction with the frame rate, Blender uses this info to calculate how fast the object should accelerate downward. Physics Steps Max Sets the maximum number of physics steps per game frame if graphics slow down the game. Higher value allows physics to keep up with real-time. Substeps Sets the number of simulation sub-steps per physics time step. Higher value give better physics precision. FPS Set the nominal number of game frames per second. Physics fixed timestep = 1/fps, independently of actual frame rate. Time Scale Time scale to slow down or speed up animations and physics in game. Logic Steps Max Sets the maximum number of logic frame per game frame if graphics slows down the game, higher value allows better synchronization with physics. Physics Deactivation These settings control the threshold at which physics is deactivated. These settings help reducing the processing spent on Physics simulation during the game. Linear Threshold The speed limit under which a rigid body will go to sleep (stop moving) if it stays below the limits for a time equal or longer than the deactivation time (sleeping is disabled when deactivation time is set to 0). Angular Threshold Same as linear threshold, but for rotation limit (in rad/s). Time The amount of time in which the object must have motion below the thresholds for physics to be disabled (0.0 disables physics deactivation). Culling Occlusion Culling Use optimized Bullet DBVT tree for view frustum and occlusion culling (more efficient, but it can waste unnecessary CPU if the scene doesn't have occluder objects). Resolution The size of the occlusion culling buffer in pixel, use higher value for better precision (slower). The optimized Bullet DBVT for view frustum and occlusion culling is activated internally by default. Object Activity Activity Culling Enable object activity culling in this scene. The culling options can be set individually by object on **Activity Culling** panel on :doc:`Object tab `. Obstacle Simulation =================== .. figure:: /images/editors-properties-scene-obstacle_simulation.png Scene tab's Obstacle Simulation panel. Simulation used for obstacle avoidance in UPBGE, based on the RVO (Reciprocal Velocity Obstacles) principle. The aim is to prevent one or more actors colliding with obstacles. Type None Obstacle simulation is disabled, actors are not able to avoid obstacles. RVO (cells) Obstacle simulation is based on the `RVO method `__ with cell sampling. RVO (rays) Obstacle simulation is based on the `RVO method `__ with ray sampling. Level height Max difference in heights of obstacles to enable their interaction. Used to define minimum margin between obstacles by height, when they are treated as those which are situated one above the other i.e. they does not influence to each other. Visualization Enable debug visualization for obstacle simulation. Navigation Mesh =============== .. figure:: /images/editors-properties-scene-navigation_mesh.png Scene tab's Navigation Mesh panel. Rasterization Cell size Rasterized cell size. Cell height Rasterized cell height. Agent Height Minimum height where the agent can still walk. Radius Radius of the agent. Max climb Maximum height between grid cells the agent can climb. Max slope Maximum walkable slope angle in degrees. Region Min Region Size Minimum regions size. Smaller regions will be deleted. Merged Region Size Minimum regions size. Smaller regions will be merged. Partitioning Watershed Classic Recast partitioning method generating the nicest tessellation. Monotone The fastest navmesh generation method, but may cause long thin polygons. Layers A reasonably fast method that produces better triangles than monotone partitioning. Polygonization Max Edge Length Maximum contour edge length. Max Edge Error Maximum distance error from contour to cells. Vertices Per Poly Max number of vertices per polygon. Detail Mesh Sample Distance Detail mesh sample spacing. Max Sample Error Detail mesh simplification max sample error. Level of Detail =============== .. figure:: /images/editors-properties-scene-level_of_detail.png Scene tab's Level of Detail panel. Hysteresis Use LoD hysteresis settings for the current scene. Slider from 0% to 100% Minimum distance change required to transition to the previous level of detail. Python Console ============== .. figure:: /images/editors-properties-scene-python_console.png Scene tab's Python Console panel. Enabling the panel's checkbox allows to trigger an interactive Python console when the game is running through the specified shortcut. Keys Set the keys to be pressed in order to activate the Python console in game. Scene ====== .. figure:: /images/editors-properties-scene-scene.png Scene tab's Scene panel. Camera Used to select which camera is used as the active camera. You can also set the active camera in the 3D View with :kbd:`Ctrl-0`. .. _scene-background-set: Background Allows you to use a scene as a background, this is typically useful when you want to focus on animating the foreground for example, without background elements getting in the way. This scene can have its own animation, physics simulations, etc, but you will have to select it from the *Scene* data-block menu, if you want to edit any of its contents. Sets can themselves have a background set (they're recursively included). So you can always make additions to existing scenes by using them as a background to a newly created scene where your additions are made. .. tip:: This can also be used in combination with Linking to a Scene, where one blend-file contains the environment, which can be reused in many places. Camera Active camera, used for rendering the scene. Background Background set scene. Units ====== .. figure:: /images/editors-properties-scene-units.png Scene tab's Units panel. Unit Presets Common unit scales to use. Length None Uses Blender Units. Metric, Imperial Standard unit of measurement for lengths. Angle Standard unit for angular measurement. Degrees, Radians .. tip:: When you are using *Degrees*, the radian value is also displayed in the tooltip. Unit Scale Scale factor to use when converting between Blender Units and *Metric*/*Imperial*. .. tip:: Usually you will want to use the *Length* presets to change to scale factor, as this does not require looking up values to use for conversion. Separate Units When *Metric* or *Imperial* display units as multiple values, for example, "2.285m" will become "2m 28.5cm". .. Normally we would avoid documenting long lists of values however, this is not displayed anywhere else. .. list-table:: Imperial Units :header-rows: 1 :stub-columns: 1 * - Full Name - Short Name(s) - Scale of a Meter * - thou - ``mil`` - 0.0000254 * - inch - ``"``, ``in`` - 0.0254 * - foot, feet - ``'``, ``ft`` - 0.3048 * - yard - ``yd`` - 0.9144 * - chain - ``ch`` - 20.1168 * - furlong - ``fur`` - 201.168 * - mile - ``mi``, ``m`` - 1609.344 .. list-table:: Metric Units :header-rows: 1 :stub-columns: 1 * - Full Name - Short Name(s) - Scale of a Meter * - micrometer - ``um`` - 0.000001 * - millimeter - ``mm`` - 0.001 * - centimeter - ``cm`` - 0.01 * - decimeter - ``dm`` - 0.1 * - meter - ``m`` - 1.0 * - dekameter - ``dam`` - 10.0 * - hectometer - ``hm`` - 100.0 * - kilometer - ``km`` - 1000.0 .. note:: The **Audio** panel settings in **Scene** tab don't have effect in UPBGE. For audio settings, see `User Preferences `__.