Unnecessary heap allocations per frame for WebGL renderer.

[itsjamie]

rdkcentral/Lightning#494

Reopening this issue which impacted Lightning 2 and still impacts Lightning 3.

renderer/src/core/renderers/webgl/WebGlCoreShader.ts

Lines 313 to 320 in 3a1fb19

	setUniform(name: string, ...value: any[]): void {
	// eslint-disable-next-line @typescript-eslint/no-non-null-assertion, @typescript-eslint/no-unsafe-argument
	this.glw.setUniform(
	this.uniformTypes[name]!,
	this.uniformLocations[name]!,
	...(value as any),
	);
	}

renderer/src/core/renderers/webgl/WebGlCoreShader.ts

Lines 313 to 320 in 3a1fb19

	setUniform(name: string, ...value: any[]): void {
	// eslint-disable-next-line @typescript-eslint/no-non-null-assertion, @typescript-eslint/no-unsafe-argument
	this.glw.setUniform(
	this.uniformTypes[name]!,
	this.uniformLocations[name]!,
	...(value as any),
	);
	}

The direct usage of the generic version of this function leads to each of those spread and rest operators creating new arrays that have to be garbage collected after each frame that includes these shaders.

If ...args was replaced with arguments usage, it is possible you could keep the generic function without the explicit array being created from the rest operator usage.

For general applications this is fine, but the moment you have an animation that includes a re-render this can quickly grow into forcing many garbage collection cycles.

[itsjamie]

As recommended in the Lightning 2 ticket, adding the explicit GL functions that take stack parameters would also resolve this, such as setUniform<1f,2f,3f,4f> etc. This would mean having to use the proper value. I think it's a fine trade to have to use the explicit function. Anyway, as before, wanted to open the issue for discussion.

[wouterlucas]

Nice - thanks for resurfacing this @itsjamie !

Tagging @erikhaandrikman and @jfboeve - lets discuss this next sync.

[wouterlucas]

Something like this @itsjamie: 79f6181 ?

[itsjamie]

Exactly like that. 👍

[wouterlucas]

ok - will noodle on that and get a PR up soonish.