Provides the base implementation for direct drawing objects that can be rendered to the backbuffer with support for opacity, fade transitions, reveal animations, and flexible positioning modes. More...

Inheritance diagram for Gondwana.Drawing.Direct.DirectDrawingBase:

Public Types
enum	RevealDirection { LeftToRight , RightToLeft , TopToBottom , BottomToTop }
	Defines the direction from which a reveal animation progressively displays the direct drawing. More...

Public Member Functions
RectangleF	GetDrawLocationScreen (View view)
	Gets the screen-space drawing location for this direct drawing as seen from the specified view.
void	Draw (BackbufferBase backbuffer, RectangleF destRectScreen)
	Renders this direct drawing to the backbuffer at the specified screen location.
DirectDrawingBase	SetOpacity (float opacity)
	Instantly sets the opacity to the specified value without animation.
DirectDrawingBase	FadeTo (float targetOpacity, float durationSec)
	Initiates a smooth fade transition to the specified target opacity over the given duration.
DirectDrawingBase	FadeIn (float durationSec)
	Fades this direct drawing from its current opacity to fully opaque over the specified duration.
DirectDrawingBase	FadeOut (float durationSec)
	Fades this direct drawing from its current opacity to fully transparent over the specified duration.
DirectDrawingBase	CancelFade ()
	Cancels any active fade transition, leaving the opacity at its current value.
DirectDrawingBase	SetReveal (float t01)
	Instantly sets the reveal progress to the specified value without animation.
DirectDrawingBase	SetRevealDirection (RevealDirection dir)
	Sets the direction from which the reveal animation progresses.
DirectDrawingBase	RevealTo (float t01, float durationSec, Func< float, float >? easing=null)
	Initiates a smooth reveal animation to the specified target progress over the given duration, optionally using a custom easing function.
virtual void	Update (long tick)
	Performs per-frame update logic for this direct drawing, including fade and reveal animations.
int	CompareTo (DirectDrawingBase? other)
	Compares this direct drawing to another for sorting by ZOrder.
void	Dispose ()
	Releases all resources used by this DirectDrawingBase instance.
override bool	Equals (object? obj)
	Determines whether the specified object is equal to the current direct drawing.
override int	GetHashCode ()
	Returns a hash code for this direct drawing.

Static Public Member Functions
static bool	operator== (DirectDrawingBase? left, DirectDrawingBase? right)
	Determines whether two direct drawing instances are equal using reference equality.
static bool	operator!= (DirectDrawingBase? left, DirectDrawingBase? right)
	Determines whether two direct drawing instances are not equal using reference equality.
static bool	operator< (DirectDrawingBase? left, DirectDrawingBase? right)
	Determines whether the Z-order of the left direct drawing is less than the right.
static bool	operator<= (DirectDrawingBase? left, DirectDrawingBase? right)
	Determines whether the Z-order of the left direct drawing is less than or equal to the right.
static bool	operator> (DirectDrawingBase? left, DirectDrawingBase? right)
	Determines whether the Z-order of the left direct drawing is greater than the right.
static bool	operator>= (DirectDrawingBase? left, DirectDrawingBase? right)
	Determines whether the Z-order of the left direct drawing is greater than or equal to the right.

Protected Member Functions
void	OnDraw (BackbufferBase backbuffer, RectangleF destRectScreen)
	Performs the concrete drawing for this direct drawing to the backbuffer.
	DirectDrawingBase (RenderSurfaceHostBase renderSurfaceHost, DirectDrawingMode mode, SceneLayer? sceneLayer, View? view, Rectangle? screenBounds, Rectangle? worldBounds, string? nickname=null)
	Initializes a new instance of the DirectDrawingBase class.
virtual void	Dispose (bool disposing)
	Releases resources used by this DirectDrawingBase instance.

Protected Attributes
readonly RenderSurfaceHostBase	_renderSurfaceHost
	The render surface host that manages this direct drawing's rendering pipeline.
Rectangle	_screenBounds
	The current screen-space bounds for view-mode direct drawings, in pixels.
Rectangle	_worldBounds
	The current world-space bounds for scene-layer-mode direct drawings, in pixels.
int	_zOrder
	The Z-order used for draw sorting. Higher values draw later (on top).
bool	_visible
	Indicates whether this direct drawing is currently visible and should be rendered.
long	_lastTick = HighResTimer.GetCurrentTick()
	The last engine tick value used for delta-time calculations in Update.

Properties
bool	HideWhenFullyTransparent = true `[get, set]`
	Gets or sets a value indicating whether this direct drawing should be automatically hidden when its opacity reaches zero during fade transitions.
RenderSurfaceHostBase	RenderSurfaceHost `[get]`
	Gets the render surface host that manages this direct drawing's rendering pipeline.
DirectDrawingMode	Mode `[get]`
	Gets the drawing mode that determines how this direct drawing is positioned and transformed.
SceneLayer?	SceneLayer `[get]`
	Gets the scene layer to which this direct drawing is attached, or `null` if the drawing is in view mode.
View?	View `[get]`
	Gets the view to which this direct drawing is attached, or `null` if the drawing is in scene-layer mode.
Rectangle	ScreenBounds `[get, set]`
	Gets or sets the screen-space bounds of this direct drawing in pixels.
Rectangle	WorldBounds `[get, set]`
	Gets or sets the world-space bounds of this direct drawing in pixels.
TypedValueBag	ValueBag = new() `[get]`
	Gets the extensible value bag for storing arbitrary key-value data associated with this direct drawing.
Guid	Id = Guid.NewGuid() `[get]`
	Gets the unique identifier for this direct drawing.
string?	Nickname `[get]`
	Gets the optional human-readable name for this direct drawing.
int	ZOrder `[get, set]`
	Gets or sets the Z-order (depth) used for sorting this direct drawing relative to other drawables.
bool	Visible `[get, set]`
	Gets or sets a value indicating whether this direct drawing is visible and should be rendered.
float	Opacity `[get, set]`
	Gets or sets the current opacity of this direct drawing.

Events
EventHandler< IDirectDrawable >?	Disposing
	Occurs when this direct drawing is being disposed.
EventHandler< DirectDrawingBase >?	FadeToCompleted
	Occurs when a fade transition initiated by FadeTo, FadeIn, or FadeOut completes.
Events inherited from Gondwana.Drawing.Direct.IDirectDrawable
EventHandler< IDirectDrawable >?	Disposing
	Occurs when the object is being disposed.

Detailed Description

Provides the base implementation for direct drawing objects that can be rendered to the backbuffer with support for opacity, fade transitions, reveal animations, and flexible positioning modes.

DirectDrawingBase serves as the foundation for all custom drawing operations in the Gondwana engine. Unlike sprites and tiles which are managed by scene layers, direct drawings provide immediate control over rendering with support for advanced visual effects.

Direct drawings can operate in two modes:

DirectDrawingMode.SceneLayer - Positioned in world coordinates relative to a specific scene layer, affected by camera and parallax.
DirectDrawingMode.View - Positioned in screen coordinates relative to a view, unaffected by camera movement (ideal for UI overlays).

This class is abstract. Derived classes must implement OnDraw to perform the actual drawing operations. The base class handles visibility, opacity, fade transitions, reveal animations, and dirty-rectangle management.

Thread safety: This class is not thread-safe. All operations should be performed on the UI thread.

Member Enumeration Documentation

◆ RevealDirection

enum Gondwana.Drawing.Direct.DirectDrawingBase.RevealDirection

Defines the direction from which a reveal animation progressively displays the direct drawing.

The reveal effect uses clipping to progressively show portions of the drawing. The direction determines which edge starts visible and how the visible region expands as the reveal progresses from 0.0 to 1.0.

Enumerator
LeftToRight	Reveals the drawing from the left edge toward the right edge.
RightToLeft	Reveals the drawing from the right edge toward the left edge.
TopToBottom	Reveals the drawing from the top edge toward the bottom edge.
BottomToTop	Reveals the drawing from the bottom edge toward the top edge.

Constructor & Destructor Documentation

◆ DirectDrawingBase()

Gondwana.Drawing.Direct.DirectDrawingBase.DirectDrawingBase	(	RenderSurfaceHostBase	renderSurfaceHost,
		DirectDrawingMode	mode,
		SceneLayer?	sceneLayer,
		View?	view,
		Rectangle?	screenBounds,
		Rectangle?	worldBounds,
		string?	nickname = null )

protected

Initializes a new instance of the DirectDrawingBase class.

Parameters

renderSurfaceHost	The render surface host that manages rendering for this direct drawing. Must not be `null`.
mode	The drawing mode determining how this object is positioned and transformed.
sceneLayer	The scene layer to which this drawing is attached (required if mode is DirectDrawingMode.SceneLayer).
view	The view to which this drawing is attached (required if mode is DirectDrawingMode.View).
screenBounds	The screen-space bounds in pixels (required if mode is DirectDrawingMode.View).
worldBounds	The world-space bounds in pixels (required if mode is DirectDrawingMode.SceneLayer).
nickname	An optional human-readable name for this direct drawing, useful for debugging and identification.

Exceptions

ArgumentNullException	Thrown when renderSurfaceHost is `null`.
ArgumentException	Thrown when: sceneLayer is `null` and mode is DirectDrawingMode.SceneLayer view is `null` and mode is DirectDrawingMode.View worldBounds is `null` and mode is DirectDrawingMode.SceneLayer screenBounds is `null` and mode is DirectDrawingMode.View

The constructor automatically registers this direct drawing with the DirectDrawingManager and marks the appropriate regions as dirty to ensure the drawing appears on the next frame.

Member Function Documentation

◆ CancelFade()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.CancelFade ( )

Cancels any active fade transition, leaving the opacity at its current value.

Returns: This DirectDrawingBase instance for method chaining.

After calling this method, the fade animation stops immediately and Opacity remains at its current value. The FadeToCompleted event will not be raised for the cancelled fade.

◆ CompareTo()

int Gondwana.Drawing.Direct.DirectDrawingBase.CompareTo ( DirectDrawingBase? other )

Compares this direct drawing to another for sorting by ZOrder.

Parameters

other The other direct drawing to compare, or null.

Returns: A negative value if this drawing's Z-order is less than other ; zero if they are equal; a positive value if this drawing's Z-order is greater. null is considered to have a Z-order of 0.

This method is used to sort direct drawings during rendering. Higher Z-order values are drawn later and appear on top of lower values.

◆ Dispose() [1/2]

void Gondwana.Drawing.Direct.DirectDrawingBase.Dispose ( )

Releases all resources used by this DirectDrawingBase instance.

This method unregisters the direct drawing from the DirectDrawingManager, marks affected regions as dirty, and raises the Disposing event. After disposal, the object should not be used.

Calling Dispose() multiple times is safe and has no additional effect.

◆ Dispose() [2/2]

virtual void Gondwana.Drawing.Direct.DirectDrawingBase.Dispose ( bool disposing )

protectedvirtual

Releases resources used by this DirectDrawingBase instance.

Parameters

disposing true to release both managed and unmanaged resources; false to release only unmanaged resources (called from finalizer).

When disposing is true, this method:

Marks affected regions as dirty by calling ForceRefresh.
Raises the Disposing event.
Clears all event handlers to prevent memory leaks.

Override this method in derived classes to release additional resources. Always call base.Dispose(disposing) to ensure proper cleanup of the base class.

Reimplemented in Gondwana.Drawing.Direct.DirectVideo, Gondwana.Drawing.Direct.Particles.ParticleSurface, and Gondwana.Drawing.Direct.TextBlock.

◆ Draw()

void Gondwana.Drawing.Direct.DirectDrawingBase.Draw	(	BackbufferBase	backbuffer,
		RectangleF	destRectScreen )

Renders this direct drawing to the backbuffer at the specified screen location.

Parameters

backbuffer	The backbuffer providing the canvas and rendering context.
destRectScreen	The destination rectangle in screen pixel coordinates.

This is the engine's entry point for rendering a direct drawing. It handles visibility checks, opacity blending via SKPaint with layer support, and reveal clipping before delegating to OnDraw for the actual drawing logic.

Do not call this method directly from game code. The rendering pipeline invokes it automatically during the render pass. To trigger a redraw, call ForceRefresh or modify properties that affect appearance.

The method applies the following operations in order:

Visibility check - returns early if Visible is false.
Reveal clipping - applies directional clipping based on SetReveal and SetRevealDirection.
Opacity blending - applies Opacity using canvas layer if less than 1.0.
Calls OnDraw to perform the actual rendering.

Implements Gondwana.Drawing.IDrawable.

◆ Equals()

override bool Gondwana.Drawing.Direct.DirectDrawingBase.Equals ( object? obj )

Determines whether the specified object is equal to the current direct drawing.

Parameters

obj	The object to compare with the current instance.

Returns: true if the specified object is the same instance as this direct drawing; otherwise, false.

This implementation uses reference equality only. Direct drawings are considered equal only if they are the exact same object instance.

◆ FadeIn()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.FadeIn ( float durationSec )

Fades this direct drawing from its current opacity to fully opaque over the specified duration.

Parameters

durationSec The duration of the fade-in in seconds.

Returns: This DirectDrawingBase instance for method chaining.

This is a convenience method equivalent to calling FadeTo(1.0f, durationSec). If the current opacity is already zero or very close to zero, it is set to exactly 0 before starting the fade to ensure a clean transition from invisible to visible.

◆ FadeOut()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.FadeOut ( float durationSec )

Fades this direct drawing from its current opacity to fully transparent over the specified duration.

Parameters

durationSec The duration of the fade-out in seconds.

Returns: This DirectDrawingBase instance for method chaining.

This is a convenience method equivalent to calling FadeTo(0.0f, durationSec). If HideWhenFullyTransparent is enabled, the object will be automatically hidden when the fade completes.

Use this for smooth disappearance effects. Combine with the FadeToCompleted event to perform cleanup or trigger subsequent logic after the fade-out finishes.

◆ FadeTo()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.FadeTo	(	float	targetOpacity,
		float	durationSec )

Initiates a smooth fade transition to the specified target opacity over the given duration.

Parameters

targetOpacity	The target opacity value (0.0 to 1.0).
durationSec	The duration of the fade in seconds. Minimum value is 0.0001 seconds.

Returns: This DirectDrawingBase instance for method chaining.

The fade animation uses linear interpolation and is updated each frame by Update. When the fade completes, the FadeToCompleted event is raised.

If the target opacity is greater than zero, Visible is automatically set to true to ensure the object is rendered during the fade. If HideWhenFullyTransparent is enabled and the target is zero, the object will be hidden when the fade completes.

Starting a new fade cancels any previous fade operation. To cancel a fade without starting a new one, call CancelFade.

◆ GetDrawLocationScreen()

RectangleF Gondwana.Drawing.Direct.DirectDrawingBase.GetDrawLocationScreen ( View view )

Gets the screen-space drawing location for this direct drawing as seen from the specified view.

Parameters

view	The view from which to calculate the screen location.

Returns: A RectangleF in screen pixel coordinates indicating where this drawing will be rendered. For view mode drawings, this returns ScreenBounds directly. For scene-layer mode drawings, this returns the WorldBounds transformed to screen space using the view's camera and the layer's parallax.

This method is used internally by the rendering pipeline to determine the destination rectangle for drawing operations. It accounts for camera position, zoom, and parallax for scene-layer mode drawings.

Implements Gondwana.Drawing.IDrawable.

◆ GetHashCode()

override int Gondwana.Drawing.Direct.DirectDrawingBase.GetHashCode ( )

Returns a hash code for this direct drawing.

Returns: A hash code based on the Nickname.

The hash code is computed using the nickname. If the nickname is null, it contributes 0 to the hash. This implementation is not suitable for dictionary keys unless nicknames are unique; use Id for unique identification.

◆ OnDraw()

void Gondwana.Drawing.Direct.DirectDrawingBase.OnDraw	(	BackbufferBase	backbuffer,
		RectangleF	destRectScreen )

abstractprotected

Performs the concrete drawing for this direct drawing to the backbuffer.

Parameters

backbuffer	The backbuffer providing the canvas and rendering context.
destRectScreen	The destination rectangle in screen pixel coordinates where this drawing should be rendered. For scene-layer mode, this is the world bounds transformed to screen space. For view mode, this is the screen bounds directly.

Override this method in derived classes to implement custom drawing logic using SkiaSharp's SKCanvas (accessible via backbuffer.Canvas).

Do not call this method directly. The engine calls it via Draw after applying visibility checks, opacity blending, and reveal clipping. The canvas state is managed by the base class; derived implementations should not call Save() or Restore() unless paired within the method.

The destination rectangle provided is already transformed to screen space and clipped to the appropriate viewport or reveal region.

◆ operator!=()

bool Gondwana.Drawing.Direct.DirectDrawingBase.operator!=	(	DirectDrawingBase?	left,
		DirectDrawingBase?	right )

static

Determines whether two direct drawing instances are not equal using reference equality.

Parameters

left	The first direct drawing to compare.
right	The second direct drawing to compare.

Returns: true if the references do not point to the same instance; otherwise, false.

◆ operator<()

bool Gondwana.Drawing.Direct.DirectDrawingBase.operator<	(	DirectDrawingBase?	left,
		DirectDrawingBase?	right )

static

Determines whether the Z-order of the left direct drawing is less than the right.

Parameters

left	The first direct drawing to compare.
right	The second direct drawing to compare.

Returns: true if left has a lower Z-order than right ; otherwise, false. null is considered to have a Z-order of 0.

◆ operator<=()

bool Gondwana.Drawing.Direct.DirectDrawingBase.operator<=	(	DirectDrawingBase?	left,
		DirectDrawingBase?	right )

static

Determines whether the Z-order of the left direct drawing is less than or equal to the right.

Parameters

left	The first direct drawing to compare.
right	The second direct drawing to compare.

Returns: true if left has a Z-order less than or equal to right ; otherwise, false. null is considered to have a Z-order of 0.

◆ operator==()

bool Gondwana.Drawing.Direct.DirectDrawingBase.operator==	(	DirectDrawingBase?	left,
		DirectDrawingBase?	right )

static

Determines whether two direct drawing instances are equal using reference equality.

Parameters

left	The first direct drawing to compare.
right	The second direct drawing to compare.

Returns: true if both references point to the same instance or are both null; otherwise, false.

◆ operator>()

bool Gondwana.Drawing.Direct.DirectDrawingBase.operator>	(	DirectDrawingBase?	left,
		DirectDrawingBase?	right )

static

Determines whether the Z-order of the left direct drawing is greater than the right.

Parameters

left	The first direct drawing to compare.
right	The second direct drawing to compare.

Returns: true if left has a higher Z-order than right ; otherwise, false. null is considered to have a Z-order of 0.

◆ operator>=()

bool Gondwana.Drawing.Direct.DirectDrawingBase.operator>=	(	DirectDrawingBase?	left,
		DirectDrawingBase?	right )

static

Determines whether the Z-order of the left direct drawing is greater than or equal to the right.

Parameters

left	The first direct drawing to compare.
right	The second direct drawing to compare.

Returns: true if left has a Z-order greater than or equal to right ; otherwise, false. null is considered to have a Z-order of 0.

◆ RevealTo()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.RevealTo	(	float	t01,
		float	durationSec,
		Func< float, float >?	easing = null )

Initiates a smooth reveal animation to the specified target progress over the given duration, optionally using a custom easing function.

Parameters

t01	The target reveal progress from 0.0 (fully hidden) to 1.0 (fully shown).
durationSec	The duration of the reveal animation in seconds. Minimum value is 0.0001 seconds.
easing	An optional easing function that transforms the linear progress (0..1 input) to the desired interpolation curve (0..1 output). If `null`, linear interpolation is used.

Returns: This DirectDrawingBase instance for method chaining.

The reveal animation is updated each frame by Update. The easing function, if provided, allows custom animation curves such as ease-in, ease-out, or elastic effects.

Starting a new reveal animation cancels any previous reveal operation. The animation starts from the current reveal value and interpolates to the target.

◆ SetOpacity()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.SetOpacity ( float opacity )

Instantly sets the opacity to the specified value without animation.

Parameters

opacity The target opacity value (0.0 to 1.0).

Returns: This DirectDrawingBase instance for method chaining.

This is equivalent to setting the Opacity property directly. It is provided for fluent-style API usage and method chaining. The value is clamped to the 0..1 range.

◆ SetReveal()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.SetReveal ( float t01 )

Instantly sets the reveal progress to the specified value without animation.

Parameters

t01	The reveal progress from 0.0 (fully hidden) to 1.0 (fully shown).

Returns: This DirectDrawingBase instance for method chaining.

The reveal effect progressively clips the rendering based on the SetRevealDirection. At 0.0, the entire drawing is clipped; at 1.0, the full drawing is visible. Values are clamped to the 0..1 range.

This method sets the reveal progress immediately. For animated reveal transitions, use RevealTo.

◆ SetRevealDirection()

DirectDrawingBase Gondwana.Drawing.Direct.DirectDrawingBase.SetRevealDirection ( RevealDirection dir )

Sets the direction from which the reveal animation progresses.

Parameters

dir	The reveal direction (left-to-right, right-to-left, top-to-bottom, or bottom-to-top).

Returns: This DirectDrawingBase instance for method chaining.

The reveal direction determines how the clip rectangle grows as the reveal progresses from 0 to 1. For example, RevealDirection.LeftToRight reveals the drawing from the left edge first, progressively showing more to the right as the reveal value increases.

◆ Update()

virtual void Gondwana.Drawing.Direct.DirectDrawingBase.Update ( long tick )

virtual

Performs per-frame update logic for this direct drawing, including fade and reveal animations.

Parameters

tick	The current engine tick value from HighResTimer.

This method is called automatically by the DirectDrawingManager each frame. The base implementation advances active fade and reveal animations. Override this method in derived classes to add custom per-frame logic (such as animation or physics updates).

Always call base.Update(tick) from overridden implementations to ensure fade and reveal animations continue to function correctly.

The method calculates delta time using HighResTimer and the previous tick stored in _lastTick. If the tick value is less than or equal to the last tick (which can occur if time is manipulated), the method returns immediately without updating state.

Implements Gondwana.Drawing.Direct.IDirectDrawable.

Reimplemented in Gondwana.Drawing.Direct.DirectDrawingMovableBase, Gondwana.Drawing.Direct.DirectRectangle, Gondwana.Drawing.Direct.Particles.ParticleSurface, and Gondwana.Drawing.Direct.TextBlock.

Member Data Documentation

◆ _lastTick

long Gondwana.Drawing.Direct.DirectDrawingBase._lastTick = HighResTimer.GetCurrentTick()

protected

The last engine tick value used for delta-time calculations in Update.

◆ _renderSurfaceHost

readonly RenderSurfaceHostBase Gondwana.Drawing.Direct.DirectDrawingBase._renderSurfaceHost

protected

The render surface host that manages this direct drawing's rendering pipeline.

◆ _screenBounds

Rectangle Gondwana.Drawing.Direct.DirectDrawingBase._screenBounds

protected

The current screen-space bounds for view-mode direct drawings, in pixels.

◆ _visible

bool Gondwana.Drawing.Direct.DirectDrawingBase._visible

protected

Indicates whether this direct drawing is currently visible and should be rendered.

◆ _worldBounds

Rectangle Gondwana.Drawing.Direct.DirectDrawingBase._worldBounds

protected

The current world-space bounds for scene-layer-mode direct drawings, in pixels.

◆ _zOrder

int Gondwana.Drawing.Direct.DirectDrawingBase._zOrder

protected

The Z-order used for draw sorting. Higher values draw later (on top).

Property Documentation

◆ HideWhenFullyTransparent

bool Gondwana.Drawing.Direct.DirectDrawingBase.HideWhenFullyTransparent = true

getset

Gets or sets a value indicating whether this direct drawing should be automatically hidden when its opacity reaches zero during fade transitions.

true to automatically hide when fully transparent (default); false to keep the object visible even at zero opacity.

When enabled, setting Opacity to 0 or completing a FadeOut will set Visible to false. Conversely, increasing opacity above zero will restore visibility.

◆ Id

Guid Gondwana.Drawing.Direct.DirectDrawingBase.Id = Guid.NewGuid()

get

Gets the unique identifier for this direct drawing.

A Guid that uniquely identifies this instance across the application lifetime.

The ID is generated during construction and remains constant throughout the object's lifetime. Use this for tracking, lookup, or equality comparisons when reference equality is not suitable.

Implements Gondwana.Drawing.IDrawable.

◆ Mode

DirectDrawingMode Gondwana.Drawing.Direct.DirectDrawingBase.Mode

get

Gets the drawing mode that determines how this direct drawing is positioned and transformed.

A DirectDrawingMode value indicating whether this drawing uses world coordinates (scene-layer mode) or screen coordinates (view mode).

The mode is set during construction and cannot be changed. Scene-layer mode drawings move with the camera and are affected by parallax, while view mode drawings remain fixed in screen space, ideal for UI overlays.

Implements Gondwana.Drawing.Direct.IDirectDrawable.

◆ Nickname

string? Gondwana.Drawing.Direct.DirectDrawingBase.Nickname

get

Gets the optional human-readable name for this direct drawing.

A string nickname for debugging and identification purposes, or null if not set.

Nicknames are useful for logging, debugging, and identifying objects in diagnostic output. They are not required to be unique.

Implements Gondwana.Drawing.IDrawable.

◆ Opacity

float Gondwana.Drawing.Direct.DirectDrawingBase.Opacity

getset

Gets or sets the current opacity of this direct drawing.

A floating-point value between 0.0 (fully transparent) and 1.0 (fully opaque). Default is 1.0.

Setting opacity automatically marks the affected regions as dirty. Values outside the 0..1 range are clamped. Very small changes (less than 0.0001) are ignored to avoid unnecessary redraws.

If HideWhenFullyTransparent is enabled:

Setting opacity to 0 automatically sets Visible to false.
Increasing opacity above 0 automatically sets Visible to true.

For animated opacity transitions, use FadeTo, FadeIn, or FadeOut.

◆ RenderSurfaceHost

RenderSurfaceHostBase Gondwana.Drawing.Direct.DirectDrawingBase.RenderSurfaceHost

get

Gets the render surface host that manages this direct drawing's rendering pipeline.

The RenderSurfaceHostBase instance responsible for coordinating rendering, view management, and backbuffer operations for this direct drawing.

Implements Gondwana.Drawing.Direct.IDirectDrawable.

◆ SceneLayer

SceneLayer? Gondwana.Drawing.Direct.DirectDrawingBase.SceneLayer

get

Gets the scene layer to which this direct drawing is attached, or null if the drawing is in view mode.

The SceneLayer instance for scene-layer mode drawings; null for view mode drawings.

Scene-layer mode drawings are positioned in the world coordinate space of the specified layer and are affected by the layer's parallax factor and the view's camera position.

◆ ScreenBounds

Rectangle Gondwana.Drawing.Direct.DirectDrawingBase.ScreenBounds

getset

Gets or sets the screen-space bounds of this direct drawing in pixels.

A Rectangle defining the position and size in screen coordinates. Returns Rectangle.Empty for scene-layer mode drawings.

This property is only meaningful for view mode drawings (Mode is DirectDrawingMode.View). Setting this property for scene-layer mode drawings has no effect.

When set, the affected screen regions are automatically marked as dirty to ensure the drawing is rerendered at the new position. The bounds are clipped to the view's viewport rectangle.

Implements Gondwana.Drawing.Direct.IDirectDrawable.

◆ ValueBag

TypedValueBag Gondwana.Drawing.Direct.DirectDrawingBase.ValueBag = new()

get

Gets the extensible value bag for storing arbitrary key-value data associated with this direct drawing.

A TypedValueBag instance for storing custom metadata, state, or configuration.

Use the value bag to attach game-specific data to direct drawings without modifying the base class. Values are strongly typed and accessed via ValueKey<T> instances.

◆ View

View? Gondwana.Drawing.Direct.DirectDrawingBase.View

get

Gets the view to which this direct drawing is attached, or null if the drawing is in scene-layer mode.

The View instance for view mode drawings; null for scene-layer mode drawings.

View mode drawings are positioned in screen coordinates relative to the specified view's viewport and remain fixed on screen regardless of camera movement.

◆ Visible

bool Gondwana.Drawing.Direct.DirectDrawingBase.Visible

getset

Gets or sets a value indicating whether this direct drawing is visible and should be rendered.

true if this drawing should be rendered; false to skip rendering. Default is true.

When set to false, Draw returns immediately without rendering. The affected regions are marked as dirty to ensure the area is cleared on the next frame.

If HideWhenFullyTransparent is enabled, visibility may be automatically managed during fade transitions based on the Opacity value.

Implements Gondwana.Drawing.IDrawable.

◆ WorldBounds

Rectangle Gondwana.Drawing.Direct.DirectDrawingBase.WorldBounds

getset

Gets or sets the world-space bounds of this direct drawing in pixels.

A Rectangle defining the position and size in world coordinates. Returns Rectangle.Empty for view mode drawings.

This property is only meaningful for scene-layer mode drawings (Mode is DirectDrawingMode.SceneLayer). Setting this property for view mode drawings has no effect.

When set, the affected world regions are automatically marked as dirty to ensure the drawing is rerendered at the new position. The bounds are subject to the layer's parallax factor and the view's camera transformation.

Implements Gondwana.Drawing.Direct.IDirectDrawable.

◆ ZOrder

int Gondwana.Drawing.Direct.DirectDrawingBase.ZOrder

getset

Gets or sets the Z-order (depth) used for sorting this direct drawing relative to other drawables.

An integer Z-order value. Higher values are drawn later and appear on top of lower values. Default is 0.

When multiple direct drawings overlap, Z-order determines the draw sequence. Objects with identical Z-order values are drawn in the order they were added to the manager. Changing the Z-order marks the affected regions as dirty to ensure correct layering on the next frame.

Implements Gondwana.Drawing.IDrawable.

Event Documentation

◆ Disposing

EventHandler<IDirectDrawable>? Gondwana.Drawing.Direct.DirectDrawingBase.Disposing

Occurs when this direct drawing is being disposed.

Subscribe to this event to perform cleanup operations when the direct drawing is removed. The event is raised before the object is fully disposed.

◆ FadeToCompleted

EventHandler<DirectDrawingBase>? Gondwana.Drawing.Direct.DirectDrawingBase.FadeToCompleted

Occurs when a fade transition initiated by FadeTo, FadeIn, or FadeOut completes.

This event is raised on the frame where the fade animation reaches its target opacity. Use this to chain animations or trigger logic after fade transitions.

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Properties

Events

Detailed Description

Member Enumeration Documentation

◆ RevealDirection

Constructor & Destructor Documentation

◆ DirectDrawingBase()

Member Function Documentation

◆ CancelFade()

◆ CompareTo()

◆ Dispose() [1/2]

◆ Dispose() [2/2]

◆ Draw()

◆ Equals()

◆ FadeIn()

◆ FadeOut()

◆ FadeTo()

◆ GetDrawLocationScreen()

◆ GetHashCode()

◆ OnDraw()

◆ operator!=()

◆ operator<()

◆ operator<=()

◆ operator==()

◆ operator>()

◆ operator>=()

◆ RevealTo()

◆ SetOpacity()

◆ SetReveal()

◆ SetRevealDirection()

◆ Update()

Member Data Documentation

◆ _lastTick

◆ _renderSurfaceHost

◆ _screenBounds

◆ _visible

◆ _worldBounds

◆ _zOrder

Property Documentation

◆ HideWhenFullyTransparent

◆ Id

◆ Mode

◆ Nickname

◆ Opacity

◆ RenderSurfaceHost

◆ SceneLayer

◆ ScreenBounds

◆ ValueBag

◆ View

◆ Visible

◆ WorldBounds

◆ ZOrder

Event Documentation

◆ Disposing

◆ FadeToCompleted