[Feat] Refractive / Reflective texture

[HouleAdrien]

Target Use Case

Hi, so using the docs and current deck.gl I've managed to make an ocean layer for my terrain.
But right now there is no simple way to get the canvas/frambuffer of the scene with filtering on layers, and this would be a huge help to have something like this to create all kind of effects that uses reflective or refactive textures.
Maybe be this is achievable with multiview but it seems really expensive, and i'm not familiar enough with luma.gl and deck.gl to think of other ways.

Proposal

So my idea was to have two things :

• a gltexture/image you could get from the deckgl instance that would be of what is in your canvas/frambuffer
• a filtering function like the layerFilter one that would allow you to filter what is shown in this texture

[ibgreen]

Deck integrates the Luma post processing system which is designed to be extensible and those effects work on the frame buffer.

Ocean / water terrain shaders have long been on the wishlist if you are willing to contribute you might get additional eyes on the code...

[HouleAdrien]

Okay, I don't know if i'm experienced enough with deck.gl to be a real contributor, but I would gladly help , maybe you could give me a lead, do you know in this how could I render my scene to a framebuffer without creating a second mapView ?
I tried following this but didn't succeed :(

this.deckGL = new Deck({ viewState: { [this.mainMapId]: this.INITIAL_VIEW_STATE, }, layerFilter: ({ layer, viewport }) => { return layer.id.startsWith(viewport.id); }, onViewStateChange: ({ viewState }) => this.deckGL?.setProps({ viewState: { [this.mainMapId]: viewState, [this.secondMapId]: viewState, }, }), controller: true, canvas, onLoad: () => { this.onMapLoaded(); }, layers: [], views: [this.originalMapView], useDevicePixels: false, });

[ibgreen]

Start by reading up on and check out effects in Luma.gl how they are implemented

https://deck.gl/docs/api-reference/core/post-process-effect

[felixpalmer]

You might want to take a look at RTTModifier & PostProcessModifier and how they can be used to create a layer here: https://github.com/visgl/deck.gl/blob/master/modules/carto/src/layers/heatmap-tile-layer.ts