Class TCastleViewport

Rendering pass, for user purposes. Useful to keep shaders cached when you render the same scene multiple times in the same frame (under different lighting conditions or other things that change shaders). By default this is always 0, the engine doesn't modify this. You can set this field manually.

Do not navigate by dragging when we're already dragging a TCastleTransform item. This means that if you drag

- X3D sensors like TouchSensor, - gizmo in CGE editor,

... then your dragging will not simultaneously also affect the navigation (which would be very disorienting).

Set to true when some TCastleTransform handles PointingDevicePress, set to false in PointingDeviceRelease.

Calculate projection parameters. Determines if the view is perspective or orthogonal and exact field of view parameters. Called each time at the beginning of rendering.

The default implementation of this method in TCastleViewport calculates projection based on the Camera parameters.

In turn, the Camera parameters may be automatically calculated (if AutoCamera) based on the nodes in the TCastleRootTransform.MainScene. Nodes like TViewpointNode or TOrthoViewpointNode or TNavigationInfoNode determine the default camera and projection details.

You can override this method, or assign the OnProjection event to adjust the projection settings. But please note: instead of overriding this method, it's usually easier (and more advised) to simply change the Camera properties, like Camera.ProjectionType or Camera.Orthographic.Width or Camera.Perspective.FieldOfView.

Prepare lights shining on everything. BaseLights contents should be initialized here. The implementation in this class adds headlight determined by the Items.UseHeadlight value.

Render everything from given camera view (as TRenderingCamera). Given RenderingCamera.Target says to where we generate the image. This method must take care of making many rendering passes for shadow volumes, but doesn't take care of updating generated textures.

Render the scene, assuming that buffers were already cleared and background was rendered. Called by RenderFromViewEverything at the end. Lights are calculated in Params at this point.

This will change Params.Transparent, Params.InShadow and Params.ShadowVolumesReceivers as needed. Their previous values do not matter.

The background used during rendering. Nil if no background should be rendered.

The default implementation in this class does what is usually most natural: return MainScene.InternalBackground, if MainScene assigned.

Render one pass, with current camera and parameters (e.g. only transparent or only opaque shapes). All current camera settings are saved in RenderParams.RenderingCamera.

Parameters

Params

Rendering parameters, see TRenderParams.

Called when PointingDevicePress was not handled by any TCastleTransform object. You can override this to make a message / sound signal to notify user that his Input_Interact click was not successful.

Warning: this symbol is deprecated: use Items.MainScene

Warning: this symbol is deprecated: use Camera to set camera properties; if you require Navigation to be <> nil, just create own instance of TCastleWalkNavigation/TCastleExamineNavigation and assign it, or call AssignDefaultNavigation

Return current navigation. Automatically creates it if missing.

Warning: this symbol is deprecated: use Camera to set camera properties; if you require Navigation to be <> nil, just create own instance of TCastleWalkNavigation/TCastleExamineNavigation and assign it, or call AssignDefaultNavigation

Warning: this symbol is deprecated: create own instance of TCastleWalkNavigation, and assign it to Viewport.Navigation, this is more flexible and predictable

Return the currently used camera as TCastleWalkNavigation, making sure that current NavigationType is something using TCastleWalkNavigation.

• When SwitchNavigationTypeIfNeeded is True (the default), this method makes sure that the NavigationType corresponds to a type handled by TCastleWalkNavigation, creating and adjusting the camera if necessary.

  If the current NavigationType does not use TCastleWalkNavigation (see TNavigationType documentation for information which navigation types use which TCastleNavigation descendants), then it's switched to ntWalk.

• When SwitchNavigationTypeIfNeeded is False, then we return Nil if the current camera is not already a TCastleWalkNavigation instance.

  We never create a new camera in this case (even if the NavigatinInfo node in MainScene would indicate that the new camera would be a TCastleWalkNavigation).

Warning: this symbol is deprecated: create own instance of TCastleWalkNavigation, and assign it to Viewport.Navigation, this is more flexible and predictable

Warning: this symbol is deprecated: create own instance of TCastleExamineNavigation, and assign it to Viewport.Navigation, this is more flexible and predictable

Return the currently used camera as TCastleExamineNavigation, making sure that current NavigationType is something using TCastleExamineNavigation.

• When SwitchNavigationTypeIfNeeded is True (the default), this method makes sure that the NavigationType corresponds to a type handled by TCastleExamineNavigation, creating and adjusting the camera if necessary.

  If the current NavigationType does not use TCastleExamineNavigation (see TNavigationType documentation for information which navigation types use which TCastleNavigation descendants), then it's switched to ntExamine.

• When SwitchNavigationTypeIfNeeded is False, then we return Nil if the current camera is not already a TCastleExamineNavigation instance.

  We never create a new camera in this case (even if the NavigatinInfo node in MainScene would indicate that the new camera would be a TCastleExamineNavigation).

Warning: this symbol is deprecated: create own instance of TCastleExamineNavigation, and assign it to Viewport.Navigation, this is more flexible and predictable

Warning: this symbol is deprecated: just set Navigation to nil instead of using this method; to avoid reusing previous instance, do not use WalkNavigation/ExamineNavigation methods, instead create and destroy your own TCastleWalkNavigation/TCastleExamineNavigation whenever you want

Make Navigation Nil. The actual creation may be caused by calling ExamineCamera, WalkCamera, InternalExamineCamera, InternalWalkCamera, or by setting NavigationType.

In all cases, these methods will create a new camera instance after a ClearCameras call. No previous cached camera instance will be used.

Warning: this symbol is deprecated: create own instance of TCastleExamineNavigation instead of using this one, it results in more obvious code

Camera instances used by this viewport. Using these methods automatically creates these instances (so they are never Nil).

Using these methods does not make these camera instances current (in contast to calling ExamineCamera, WalkCamera or setting NavigationType).

When you switch navigation types by calling ExamineCamera, WalkCamera or setting NavigationType the viewport keeps using these instances of cameras, instead of creating new camera instances. This way all the camera properties (not only those copied by TCastleNavigation.Assign) are preserved when you switch e.g. NavigationType from ntWalk to ntExamine to ntWalk again.

This is deprecated now, because it causes auto-detection of navigation parameters, which is (in general) more surprising than helpful. E.g. it adjusts camera radius, speed and more properties.

Warning: this symbol is deprecated: create own instance of TCastleWalkNavigation instead of using this one, it results in more obvious code

Warning: this symbol is deprecated: use InternalExamineNavigation

Warning: this symbol is deprecated: use InternalWalkNavigation

Assign Navigation to a default TCastleNavigation suitable for navigating in this scene.

This is automatically used when Navigation is Nil and AutoNavigation. You can also use it explicitly.

The implementation in base TCastleViewport uses MainScene.NavigationTypeFromNavigationInfo and MainScene.InternalUpdateNavigation, thus it follows your X3D scene NavigationInfo. If MainScene is not assigned, we create a simple navigation in Examine mode.

Assign initial and current camera vectors and projection.

This is automatically used at first rendering if AutoCamera. You can also use it explicitly.

Does the graphic card support our ScreenSpaceAmbientOcclusion shader. This does not depend on the current state of ScreenSpaceAmbientOcclusion property. You can use it e.g. to disable the menu item to switch SSAO in 3D viewer.

Does the graphic card support our ScreenSpaceReflections shader. This does not depend on the current state of ScreenSpaceReflections property. You can use it e.g. to disable the menu item to switch SSR in 3D viewer.

Parameters to prepare items that are to be rendered within this world. This should be passed to TCastleTransform.PrepareResources.

Note: Instead of using TCastleTransform.PrepareResources, and this method, it's usually easier to call TCastleViewport.PrepareResources. Then the appropriate TPrepareParams will be passed automatically.

Warning: this symbol is deprecated: this is internal info, you should not need this; use PrepareParams to get opaque information to pass to TCastleTransform.PrepareResources

Statistics about last rendering frame. See TRenderStatistics docs.

Current 3D triangle under the mouse cursor. Updated in every mouse move. May be Nil.

Utility method to set camera to a suitable state for 2D games.

• Sets both initial and current camera vectors like this:

  • Position camera at (0, 0, 500),

  • Looks along the -Z direction,

  • "Up" vector is in +Y.

  This way the 2D world spans horizontally in X and vertically in Y. The Z (depth) can be used to put things in front/behind each other.

  Since this initialized the camera sensibly, we also set AutoCamera to false.

• Sets orthographic projection for the camera (TCastleCamera.ProjectionType set to ptOrthographic).

  By default our visible X range is [0..viewport width in pixels], visible Y range is [0..viewport height in pixels]. Use the properties of Camera.Orthographic to control the projection. For example set Camera.Orthographic.Width and/or Camera.Orthographic.Height to define visible projection size (horizontal or vertical) explicitly, regardless of the viewport size.

  Setting Camera.Orthographic.Origin is also often useful, e.g. set it to (0.5,0.5) to make the things positioned at (0,0) in the world visible at the middle of the viewport.

  By default our visible Z range is [-1500, 500], because this sets ProjectionNear to -1000, ProjectionFar to 1000, and camera default depth (Camera.Position.Z) is 500. This was chosen to be comfortable for all cases – you can keep camera Z unchanged and comfortably position things around [-500, 500], or set camera Z to zero and then comfortably position things around [-1000, 1000].

Convert 2D position on the viewport into 3D "world coordinates", by colliding camera ray with a plane parallel to the viewport at given Depth. "World coordinates" are coordinates space seen by TCastleTransform / TCastleScene inside viewport Items. Use Depth > 0 for positions in front of the camera.

This is similar to "Unproject" GLU routine. It allows to map points from the screen back to the 3D space inside viewport.

The interpretation of Position depends on ScreenCoordinates, and is similar to e.g. TCastleTiledMapControl.PositionToTile:

• When ScreenCoordinates = True, then Position is relative to the whole container (like TCastleWindowBase or TCastleControlBase).

  And it is expressed in real device coordinates, just like TInputPressRelease.Position when mouse is being clicked, or like TInputMotion.Position when mouse is moved.

• When ScreenCoordinates = False, then Position is relative to this UI control.

  And it is expressed in coordinates after UI scaling. IOW, if the size of this control is Width = 100, then Position.X between 0 and 100 reflects the visible range of this control.

Returns true and sets 3D PlanePosition if such intersection is found. Returns false if it's not possible to determine such point (which should not be possible, unless camera field of view is larger than 180 degrees).

Convert 2D position on the viewport into 3D ray.

The interpretation of Position depends on ScreenCoordinates, and is similar to e.g. TCastleTiledMapControl.PositionToTile:

• When ScreenCoordinates = True, then Position is relative to the whole container (like TCastleWindowBase or TCastleControlBase).

  And it is expressed in real device coordinates, just like TInputPressRelease.Position when mouse is being clicked, or like TInputMotion.Position when mouse is moved.

• When ScreenCoordinates = False, then Position is relative to this UI control.

  And it is expressed in coordinates after UI scaling. IOW, if the size of this control is Width = 100, then Position.X between 0 and 100 reflects the visible range of this control.

Convert 2D position on the viewport into 3D "world coordinates", by colliding camera ray with a plane at constant Z. "World coordinates" are coordinates space seen by TCastleTransform / TCastleScene inside viewport Items.

This is a more general version of PositionTo2DWorld, that works with any projection (perspective or orthographic). This is often useful if your game is "close to 2D", which means that you use 3D (and maybe even perspective camera), but most of the game world is placed around some plane with constant Z.

The interpretation of Position depends on ScreenCoordinates, and is similar to e.g. TCastleTiledMapControl.PositionToTile:

• When ScreenCoordinates = True, then Position is relative to the whole container (like TCastleWindowBase or TCastleControlBase).

  And it is expressed in real device coordinates, just like TInputPressRelease.Position when mouse is being clicked, or like TInputMotion.Position when mouse is moved.

• When ScreenCoordinates = False, then Position is relative to this UI control.

  And it is expressed in coordinates after UI scaling. IOW, if the size of this control is Width = 100, then Position.X between 0 and 100 reflects the visible range of this control.

This intersects the ray cast by Camera with a plane at Z = PlaneZ.

Returns true and sets 3D PlanePosition (the Z component of this vector must always be equal to PlaneZ) if such intersection is found. Returns false if it's not possible to determine such point (when the camera looks in the other direction).

Convert 2D position into "world coordinates", which is the coordinate space seen by TCastleTransform / TCastleScene inside viewport Items, assuming that we use orthographic projection in XY axes.

The interpretation of Position depends on ScreenCoordinates, and is similar to e.g. TCastleTiledMapControl.PositionToTile:

• When ScreenCoordinates = True, then Position is relative to the whole container (like TCastleWindowBase or TCastleControlBase).

  And it is expressed in real device coordinates, just like TInputPressRelease.Position when mouse is being clicked, or like TInputMotion.Position when mouse is moved.

• When ScreenCoordinates = False, then Position is relative to this UI control.

  And it is expressed in coordinates after UI scaling. IOW, if the size of this control is Width = 100, then Position.X between 0 and 100 reflects the visible range of this control.

This assumes that camera "up vector" is +Y, and it is looking along the negative Z axis. It also assumes orthographic projection (Camera.ProjectionType equal ptOrthographic). These are default camera direction, up and projection types set by Setup2D.

Prepare resources, to make various methods (like Render) execute fast. Call it only when rendering context is initialized (ApplicationProperties.IsGLContextOpen). If DisplayProgressTitle <> '', we will display progress bar during loading.

Current object (TCastleTransform instance) under the mouse cursor. Updated in every mouse move. May be Nil.

Warning: this symbol is deprecated: in most cases, you can instead read Camera parameters, like Camera.Orthographic.EffectiveWidth, Camera.Orthographic.EffectiveHeight

Current projection parameters, calculated by last CalculateProjection call, adjusted by OnProjection. This is read only. To change the projection parameters, override CalculateProjection or handle event OnProjection.

Screen effects are shaders that post-process the rendered screen. If any screen effects are active, we will automatically render screen to a temporary texture, processing it with each shader.

By default, screen effects come from MainScene.ScreenEffects, so the effects may be defined by VRML/X3D author using ScreenEffect nodes (see docs: [https://castle-engine.io/x3d_extensions_screen_effects.php]). Descendants may override GetScreenEffects, ScreenEffectsCount, and ScreenEffectsNeedDepth to add screen effects by code. Each viewport may have it's own, different screen effects.

Background color, displayed behind the 3D world. Unless the MainScene has a Background node defined, in which case the Background (colored and/or textured) of the 3D scene is used.

Dark gray (DefaultBackgroundColor) by default.

Enable built-in SSAO screen effect in the world.

Enable built-in SSR screen effect in the world.

Adjust SSR default surface glossiness.

Called on any camera change.

Set Navigation and some of its' parameters (like TCastleWalkNavigation.Gravity and so on).

If AutoNavigation, the initial Navigation as well as initial value of this property are automatically determined by the currently bound X3D NavigatinInfo node in the MainScene, and world bounding box. They are also automatically adjusted e.g. when current NavigatinInfo node changes.

But you can set Navigation, or this property, manually to override the detected navigation. You should set AutoNavigation to False to take control of Navigation and this property completely (no auto-detection based on MainScene will then take place).

Note that you can also affect the current NavigationType by directly changing the camera properties, e.g. you can directly change TCastleWalkNavigation.Gravity from False to True, and thus you effectively switch from ntFly to ntWalk navigation types. When you read the NavigationType property, we determine the current navigation type from current camera properties.

Setting this sets:

• TCastleNavigation.Input

• TCastleExamineNavigation.Turntable, only in case of TCastleExamineNavigation

• TCastleWalkNavigation.Gravity, only in case of TCastleWalkNavigation

• TCastleWalkNavigation.PreferGravityUpForRotations, only in case of TCastleWalkNavigation

• TCastleWalkNavigation.PreferGravityUpForMoving, only in case of TCastleWalkNavigation

If you write to NavigationType, then you should not touch the above properties directly. That's because not every combination of above properties correspond to some sensible value of NavigationType. If you directly set some weird configuration, reading NavigationType will try it's best to determine the closest TNavigationType value that is similar to your configuration.

Current object (TCastleTransform hierarchy) under the mouse cursor. Updated in every mouse move. May be Nil.

The returned list (if not Nil) contains TCastleTransform instances that collided with the ray (from the deepest instance in the Items tree to the root), along with some additional information. See TRayCollision for details.

Do not collide with this object when moving by Navigation. It makes sense to put here player avatar (in 3rd person view) or player collision volume (in 1st person view) to allow player to move, not colliding with its own body.

In case of using TLevel, this is automatically set when you set TLevel.Player.

Warning: this symbol is deprecated: use Items.Paused

See TCastleAbstractRootTransform.Paused.

Warning: this symbol is deprecated: assign Items from one TCastleViewport to another to view the same world from multiple viewports

Transformations and scenes visible in this viewport. You should add here your TCastleTransform and TCastleScene instances.

It is by default created (not nil), but you can also assign here your own TCastleRootTransform instance. You can also copy a TCastleRootTransform from one TCastleViewport to another, that is multiple TCastleViewport can refer to the same TCastleRootTransform instance.

Camera determines the viewer position and orientation. The given camera instance is always available and connected with this viewport.

Navigation method is an optional component that handles the user input to control the camera.

You can assign here an instance of TCastleNavigation, like TCastleWalkNavigation or TCastleExamineNavigation. Or you can leave it as Nil.

Note that, if you leave it as Nil and have AutoNavigation as True (default) then a default navigation will be calculated right before the first rendering. It will take into account the 3D world initialized in Viewport.Items, e.g. the NavigatinInfo inside Viewport.Items.MainScene. Set AutoNavigation to false to avoid this automatic detection.

Note that assigning NavigationType also implicitly sets this property to an internal instance of TCastleWalkNavigation or TCastleExamineNavigation. Setting NavigationType to Nil sets this property to Nil.

See also

OnCameraChanged

Called on any camera change.

Warning: this symbol is deprecated: do not customize rendering with this; instead add TCastleUserInterface descendants where you can override TCastleUserInterface.Render to do custom rendering

See Render3D method.

Should we render with shadow volumes. You can change this at any time, to switch rendering shadows on/off.

This works only if OpenGL context actually can render shadow volumes, checked by GLFeatures.ShadowVolumesPossible, which means that you have to initialize OpenGL context with stencil buffer.

The shadow volumes algorithm is used only if shadow caster is 2-manifold, that is has a correctly closed volume. Also you need a light source marked as the main shadow volumes light (shadowVolumes = shadowVolumesMain = TRUE). See [https://castle-engine.io/x3d_extensions.php#section_ext_shadows] for details.

Actually draw the shadow volumes to the color buffer, for debugging. If shadows are rendered (see GLFeatures.ShadowVolumesPossible and ShadowVolumes), you can use this to actually see shadow volumes, for debug / demo purposes. Shadow volumes will be rendered on top of the scene, as yellow blended polygons.

If yes then the scene background will be rendered wireframe, over the background filled with BackgroundColor.

There's a catch here: this works only if the background is actually internally rendered as a geometry. If the background is rendered by clearing the screen (this is an optimized case of sky color being just one simple color, and no textures), then it will just cover the screen as normal, like without wireframe. This is uncertain situation anyway (what should the wireframe look like in this case anyway?), so I don't consider it a bug.

Useful especially for debugging when you want to see how your background geometry looks like.

If yes then the viewport will not draw a background, letting the window contents underneath be visible (on pixels which are not drawn by this viewport's Items, and on pixels which are drawn but with partially-transparent materials).

In effect, the BackgroundColor, BackgroundWireframe, and any background defined using X3D nodes (like TBackgroundNode, TTextureBackgroundNode, TImageBackgroundNode) inside MainScene will be ignored.

At the beginning of rendering, viewport by default clears the depth buffer. This makes every viewport draw everything on top of the previous 2D and 3D stuff (including on top of previous viewport), like a layer.

You can disable this, which allows to combine together the 3D objects rendered by various viewports (and by custom OpenGL rendering), such that the 3D positions determime what overlaps what. This only makes sense if you have a number of TCastleViewport instances, that share the same size and position on the screen, same projection and the same camera.

It's your responsibility in such case to clear the depth buffer. E.g. place one viewport in the back that has ClearDepth = True. Or place a TCastleUserInterface descendant in the back, that calls TRenderContext.Clear RenderContext.Clear in overridden TCastleUserInterface.Render.

Note: to disable clearning the color buffer, set Transparent to False.

Note: if you use shadow volumes, we will still clear the stencil buffer at the beginning of rendering.

Let MainScene.GlobalLights shine on every 3D object, not only MainScene. This is an easy way to lit your whole world with lights defined inside MainScene file. Be sure to set lights global=TRUE.

Note that for now this assumes that MainScene coordinates equal world coordinates. This means that you should not transform the MainScene, it should be placed inside TCastleViewport.Items and not transformed by TCastleTransform.

Let the fog defined in MainScene affect all objects, not only MainScene. This is consistent with UseGlobalLights, that allows lights from MainScene to shine on all objects.

Help user to activate pointing device sensors and pick items. Every time you press Input_Interact (by default just left mouse button), we look if current mouse/touch position hits an object (TCastleTransform) that actually does something on activation. The object may do various stuff inside TCastleTransform.PointingDevicePress, generally this causes various picking/interaction with the object (like pulling a level, opening a door), possibly dragging, possibly with the help of VRML/X3D pointing device and drag sensors.

When this is True, we try harder to hit some 3D object that handles PointingDevicePress. If there's nothing interesting under mouse/touch, we will retry a couple of other positions around the current mouse/touch.

This should be usually used when you use TCastleMouseLookNavigation.MouseLook, or other navigation when mouse cursor is hidden. It allows user to only approximately look at interesting item and hit interaction button or key. Otherwise, activating a small object is difficult, as you don't see the cursor.

Warning: this symbol is deprecated: use Camera.ProjectionFar, and set AutoCamera to false

Visibility limit of your 3D world. This is the distance the far projection clipping plane.

The default CalculateProjection implementation calculates the final visibility limit as follows:

• First of all, if (GLFeatures.ShadowVolumesPossible and ShadowVolumes), then it's infinity.

• Then we look NavigationInfo.visibilityLimit value inside MainScene. This allows your 3D data creators to set this inside VRML/X3D data.

  Only if MainScene is not set, or doesn't contain NavigationInfo node, or NavigationInfo.visibilityLimit is left at (default) zero, we look further.

• We use this property, DefaultVisibilityLimit, if it's not zero.

• Finally, as a last resort we calculate something suitable looking at the 3D bounding box of items inside our 3D world.

Warning: this symbol is deprecated: adjust projection by changing Camera.ProjectionType and other projection parameters inside Camera

Adjust the projection parameters. This event is called before every render. See the CalculateProjection for a description how to default projection parameters are calculated.

Enable to drag a parent control, for example to drag a TCastleScrollView that contains this TCastleViewport, even when the scene inside contains clickable elements (using TouchSensor node).

To do this, you need to turn on TCastleScrollView.EnableDragging, and set EnableParentDragging=True here. In effect, viewport will cancel the click operation once you start dragging, which allows the parent to handle all the motion events for dragging.

Assign initial camera properties (initial position, direction, up, TCastleCamera.ProjectionNear) by looking at the initial world (Items) when rendering the first frame.

The AssignDefaultCamera is automatically called only if this property is True.

Also, only if this property is True, we synchronize camera when X3D Viewpoint node changes, or a new X3D Viewpoint node is bound.

By default it is False, which means you control Camera properties on your own.

Assign sensible Navigation looking at the initial world (Items) if it is not assigned.

This also allows to later synchronize navigation properties when X3D NavigationInfo node changes, or a new NavigationInfo node is bound.

By default it is False, which means that you control Navigation on your own.

Called when bound Viewpoint node changes. Called exactly when TCastleSceneCore.ViewpointStack.OnBoundChanged is called.

Called when bound NavigationInfo changes (to a different node, or just a field changes).

Protect from falling down because of gravity when position is outside of world bounding box. This is a nice thing for general model viewers (like view3dscene), to prevent from accidentally falling down when using "Walk" mode.

This is only used by navigations performing gravity internally, that is right now: TCastleWalkNavigation (when TCastleWalkNavigation.Gravity = True).

BackgroundColor that can be visually edited in Castle Game Engine Editor, Lazarus and Delphi. Normal user code does not need to deal with this, instead read or write BackgroundColor directly.

See also

BackgroundColor

Background color, displayed behind the 3D world.