Examples: Add setSize() to more post-processing passes.

[Mugen87]

Related issue: -

Description

This PR adds some missing setSize() methods to post-processing passes.

BTW: There is some redundant code in the post-processing passes since it is actually not always necessary to apply the dimensions of the pass at creation time. When a pass is added to the pass chain, the pass is automatically resized by the width and height of the composer. So as long as setSize() is properly implemented, internal render targets can be defined with a default (1,1) resolution.

[WestLangley]

I think that will cause confusion to users without an explanation.

How about adding a comment:

this.renderTargetY = new WebGLRenderTarget( 1, 1 ); // will be resized later

Maybe there is a more-precise comment you could add.

[Mugen87]

Instead of adding a comment, how about we add 1 as a default parameter for width and height in WebGLRenderTragets ctor?

three.js/src/renderers/WebGLRenderTarget.js

Line 14 in 03efa5a

constructor( width, height, options = {} ) {

In this way we can just write const renderTarget = new WebGLRenderTarget(); which simplifies the code even more. We also allow other objects like geometries, materials and 3D objects to be created without arguments.

[WestLangley]

Hehe. I suggested that too, but removed it for simplicity. That is fine.

I still think adding the comment would be helpful, though.

[Mugen87]

Okay, then let me add the comments now and change the ctor of WebGLRenderTarget with a different PR.