Create a new CanvasViewport.
Creates a new canvas with a starting width and height, setting canvas and context. Failure to get a canvas context results in an exception.
Texture bleeding prevention should be enabled for CanvasViewports that are used as the output (top-most) Viewport, but only if the Viewport will be used in a 3D engine. If used in, for example, a DOMRoot, then there should be no texture bleeding issues, so texture bleeding prevention is disabled for DOMRoots. For engines like Wonderland Engine, texture bleeding prevention is enabled.
Should not be used in nested Viewports as there are no texture bleeding issues in nested Viewports; it technically can be enabled, but it would be a waste of resources.
Protected _forceDoes the canvas size need to be updated? For internal use only.
Private _prevESXPrevious horizontal effective scale. For internal use only.
Private _prevESYPrevious vertical effective scale. For internal use only.
Readonly canvasThe internal canvas. Widgets are painted to this
Readonly childThe Viewport's child. Painting and layout will be relative to this.
Layout constraints of viewport when resolving widget's layout. A 4-tuple containing, respectively, minimum width, maximum width, minimum height and maximum height.
By default, has no minimum width nor height and unconstrained maximum width and height.
Readonly contextThe render target's (canvas) 2D context. Alpha is enabled.
Note that readonly in this context means that this property is a getter, not that it is immutable. Ideally, this is a getter that gets the current rendering context. Some Viewport implementations (such as CanvasViewport) will always use the same context, while others (such as ClippedViewport) will occasionally change the context.
The maximum height the canvas can have. If the layout exceeds this height, then the content will be scaled to fit the canvas
The maximum width the canvas can have. If the layout exceeds this width, then the content will be scaled to fit the canvas
The offset of the child inside the Viewport. Depending on the Viewport implementation, this may update the actual position of the child Widget, or it may just affect how the paint method behaves.
The parent Viewport of this Viewport. Since positions are relative to this, absolute positions can be calculated by following all the parents.
If null, this is the topmost Viewport and owned by the UI Root.
Should be set by the owner when the owner is attached or detached.
Is texture bleeding prevention enabled? If true, then out-of-bounds old painted Widgets that were kept because of the canvas shrinking will be cleared after the paint method is called.
Can be changed at any time, but will only take effect once the child Widget is re-painted.
The actual dimensions and position of the viewport, relative to the parent Viewport (or the UI Root if there is no parent Viewport, meaning that positions are absolute in that case); for example, this would be the equivalent to an iframe's dimensions and position (the HTML body in the iframe can have different dimensions than the iframe itself and be scrolled by some amount).
Do not use this value for resolving the layout. Only use this for event handling or other logic that doesn't affect layout.
Should be set by the owner of the Viewport (a Root or a ViewportWidget) when finalizing layout.
Readonly relativeThe coordinate system used for this Viewport. If true, then coordinates are relative to the Viewport itself (child always has a position of 0,0). If false, then coordinates are absolute (relative to the nearest relative parent Viewport, or topmost Viewport, or 0,0 if this is the topmost Viewport).
The resolution of the canvas. If possible, the canvas will be scaled by this amount.
Private shrunkHas the "real" size of the child Widget in the canvas shrunk? Used for texture bleeding prevention. For internal use only.
Will be ignored if preventBleeding is false.
Static Protected dimensionlessHas the warning for dimensionless canvases been issued?
Static Protected maxThe maximum retries allowed for resolving the layout. The first attempt is not counted. Only retries that exceed this limit are discarded; if maxRelayout is 4, then the 5th retry will be discarded.
Static Protected powerHas the warning for non-power of 2 dimensions been issued?
The current dimensions of the internal canvas
Get the canvas scale that will be applied to the Viewport's child. Used for checking whether a child's dimensions exceeds a canvas' maximum dimensions.
Note that readonly in this context means that this property is a getter, not that it is immutable. Ideally, this is a getter that calculates the effective scale of the viewport via the canvas dimensions and max dimensions, which may returns different values, not the same value every time.
Private realThe "real" dimensions of the child Widget; the dimensions that the child Widget occupies in the canvas, taking resolution and maximum canvas dimensions into account.
Protected getGet the rect of the child alongside more extra information, clipped/clamped to the bounds of the viewport. For internal use only.
Implements paint, but only paints to the internal canvas. Call this instead of paint if you are using this Viewport's canvas as the output canvas (such as in the Root).
Resolves the Viewport child's layout (including position) in one call, using the previous position.
May resize or rescale the canvas.
Expands canvas if the new layout is too big for the current canvas. Expansion is done in powers of 2 to avoid issues with external 3D libraries.
Returns true if the widget or canvas were resized, or the canvas rescaled, else, false.
Generated using TypeDoc
A Viewport with an internal canvas, where the rendering context used for the Viewport is the internal canvas' context instead of an inherited context from a parent Viewport.
Mostly used as the top-most Viewport, such as the Viewport in a Root.
Coordinates are relative to the internal canvas, instead of absolute. Because of this, viewport contents may be blurred if the position of the viewport is fractional.