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Documentation / scene / DualDepthPeelingOIT

Class: DualDepthPeelingOIT

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:39

Dual depth peeling OIT renderer.

Remarks

This implementation follows the official dual depth peeling pass structure: an initialization pass writes the nearest/farthest transparent depth pair, then each peel pass ping-pongs the depth pair while accumulating front and back colors.

It requires MRT, per-target blending, min/max blend equations and blendable floating-point color targets. If those capabilities are missing, supportDevice() returns false and the transparent pass falls back to sorted alpha blending.

Extends

Constructors

Constructor

new DualDepthPeelingOIT(numPeels?): DualDepthPeelingOIT

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:62

Creates an instance of DualDepthPeelingOIT.

Parameters

numPeels?

number = 8

Number of peel iterations after the initialization pass.

Returns

DualDepthPeelingOIT

Overrides

OIT.constructor

Properties

type

readonly static type: "ddp" = 'ddp'

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:41

Type name of DualDepthPeelingOIT

Accessors

disposed

Get Signature

get disposed(): boolean

Defined in: libs/base/dist/index.d.ts:6107

Returns

boolean

Inherited from

OIT.disposed


numPeels

Get Signature

get numPeels(): number

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:75

Number of front/back peel iterations after the initialization pass.

Returns

number

Set Signature

set numPeels(val): void

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:78

Parameters
val

number

Returns

void


uniformTag

Get Signature

get uniformTag(): number

Defined in: libs/scene/src/render/oit.ts:29

Returns

number

Inherited from

OIT.uniformTag

Methods

on()

on<K>(type, listener, context?): void

Defined in: libs/base/dist/index.d.ts:630

IEventTarget.on

Type Parameters

K

K extends "dispose"

Parameters

type

K

listener

EventListener<{ dispose: []; }, K>

context?

unknown

Returns

void

Inherited from

OIT.on


once()

once<K>(type, listener, context?): void

Defined in: libs/base/dist/index.d.ts:634

IEventTarget.once

Type Parameters

K

K extends "dispose"

Parameters

type

K

listener

EventListener<{ dispose: []; }, K>

context?

unknown

Returns

void

Inherited from

OIT.once


off()

off<K>(type, listener?, context?): void

Defined in: libs/base/dist/index.d.ts:638

IEventTarget.off

Type Parameters

K

K extends "dispose"

Parameters

type

K

listener?

EventListener<{ dispose: []; }>

context?

unknown

Returns

void

Inherited from

OIT.off


dispatchEvent()

dispatchEvent<K>(type, ...args): void

Defined in: libs/base/dist/index.d.ts:642

IEventTarget.dispatchEvent

Type Parameters

K

K extends "dispose"

Parameters

type

K

args

...object[K]

Returns

void

Inherited from

OIT.dispatchEvent


dispose()

dispose(): void

Defined in: libs/base/dist/index.d.ts:6108

Returns

void

Inherited from

OIT.dispose


supportDeviceCaps()

static supportDeviceCaps(deviceType, caps): boolean

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:89

Checks whether dual depth peeling can run with a capability snapshot.

Parameters

deviceType

string

The device type.

caps

DeviceCaps

The device capabilities.

Returns

boolean

True if dual depth peeling is supported.


getType()

getType(): string

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:110

Returns the type of the renderer.

Returns

string

The type of the renderer.

Overrides

OIT.getType


supportDevice()

supportDevice(deviceType): boolean

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:117

Checks whether the renderer supports the given device type.

Parameters

deviceType

string

The device type.

Returns

boolean

True if the renderer supports the device type, false otherwise.

Overrides

OIT.supportDevice


wantsPremultipliedAlpha()

wantsPremultipliedAlpha(): boolean

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:129

Whether this OIT algorithm wants pre-multiplied alpha

Returns

boolean

True if the OIT wants pre-multiplied alpha, false otherwise

Overrides

OIT.wantsPremultipliedAlpha


wantsAdditiveLightPassAlpha()

wantsAdditiveLightPassAlpha(): boolean

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:136

Whether additive light passes should keep the material alpha before OIT output.

Returns

boolean

Remarks

Some OIT algorithms need the original material alpha to weight additive light color, but write zero alpha to their accumulation targets so transmittance is not counted twice.

Overrides

OIT.wantsAdditiveLightPassAlpha


begin()

begin(ctx): number

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:143

Begins rendering the transparent objects.

Parameters

ctx

DrawContext

The draw context.

Returns

number

The number of passes required for rendering.

Remarks

Contract: the caller (the transparent scene pass) must have explicitly bound the transparent scene target framebuffer before calling begin(), beginPass() or endPass(). Implementations may redirect rendering to internal buffers, but must composite into that bound target and restore it before returning.

Overrides

OIT.begin


end()

end(ctx): void

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:156

Ends rendering the transparent objects.

Parameters

ctx

DrawContext

The draw context.

Returns

void

Overrides

OIT.end


beginPass()

beginPass(ctx, pass): boolean

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:170

Begins rendering for the given pass.

Parameters

ctx

DrawContext

The draw context.

pass

number

The pass number.

Returns

boolean

True if the transparent objects should be rendered, false otherwise.

Overrides

OIT.beginPass


endPass()

endPass(ctx, _pass): void

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:198

Ends rendering for the given pass.

Parameters

ctx

DrawContext

The draw context.

_pass

number

The pass number.

Returns

void

Overrides

OIT.endPass


setupFragmentOutput()

setupFragmentOutput(scope): void

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:205

Sets up the fragment output.

Parameters

scope

PBGlobalScope

The global shader scope.

Returns

void

Remarks

This method declares necessary uniform variables for OIT rendering and injects it into the object's material.

Overrides

OIT.setupFragmentOutput


outputFragmentColor()

outputFragmentColor(scope, color, ctx): boolean

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:218

Do the fragment color output.

Parameters

scope

PBInsideFunctionScope

The global shader scope.

color

PBShaderExp

The calculated fragment color.

ctx

DrawContext

Returns

boolean

Remarks

This method outputs the calculated fragment color for OIT rendering and injects it into the object's material.

Overrides

OIT.outputFragmentColor


applyUniforms()

applyUniforms(_ctx, bindGroup): void

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:280

Applies the uniforms for the given draw context and bind group.

This function will be called when ever the transparent material will upload uniform variables.

Parameters

_ctx

DrawContext

The draw context.

bindGroup

BindGroup

The bind group.

Returns

void

Overrides

OIT.applyUniforms


calculateHash()

calculateHash(): string

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:289

Calculates the hash of the renderer.

Returns

string

The hash of the renderer.

Remarks

When this hash value was changed, material shader will be forced recreate.

Overrides

OIT.calculateHash


setRenderStates()

setRenderStates(rs): void

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:296

Sets the render states for the renderer.

This function will be called when the transparent object will be rendered.

Parameters

rs

RenderStateSet

The render states.

Returns

void

Overrides

OIT.setRenderStates


onDispose()

protected onDispose(): void

Defined in: libs/scene/src/render/dualdepthpeeling_oit.ts:447

Returns

void

Overrides

OIT.onDispose


uniformChanged()

uniformChanged(): void

Defined in: libs/scene/src/render/oit.ts:32

Returns

void

Inherited from

OIT.uniformChanged

Released under the MIT License.