animate/webGl/my-threejs-test/node_modules/three/examples/jsm/materials/MeshPostProcessingMaterial.js

145 lines
4.0 KiB
JavaScript

import { MeshPhysicalMaterial } from 'three';
/**
* The aim of this mesh material is to use information from a post processing pass in the diffuse color pass.
* This material is based on the MeshPhysicalMaterial.
*
* In the current state, only the information of a screen space AO pass can be used in the material.
* Actually, the output of any screen space AO (SSAO, GTAO) can be used,
* as it is only necessary to provide the AO in one color channel of a texture,
* however the AO pass must be rendered prior to the color pass,
* which makes the post-processing pass somewhat of a pre-processing pass.
* Fot this purpose a new map (`aoPassMap`) is added to the material.
* The value of the map is used the same way as the `aoMap` value.
*
* Motivation to use the outputs AO pass directly in the material:
* The incident light of a fragment is composed of ambient light, direct light and indirect light
* Ambient Occlusion only occludes ambient light and environment light, but not direct light.
* Direct light is only occluded by geometry that casts shadows.
* And of course the emitted light should not be darkened by ambient occlusion either.
* This cannot be achieved if the AO post processing pass is simply blended with the diffuse render pass.
*
* Further extension work might be to use the output of an SSR pass or an HBIL pass from a previous frame.
* This would then create the possibility of SSR and IR depending on material properties such as `roughness`, `metalness` and `reflectivity`.
**/
class MeshPostProcessingMaterial extends MeshPhysicalMaterial {
constructor( parameters ) {
const aoPassMap = parameters.aoPassMap;
const aoPassMapScale = parameters.aoPassMapScale || 1.0;
delete parameters.aoPassMap;
delete parameters.aoPassMapScale;
super( parameters );
this.onBeforeCompile = this._onBeforeCompile;
this.customProgramCacheKey = this._customProgramCacheKey;
this._aoPassMap = aoPassMap;
this.aoPassMapScale = aoPassMapScale;
this._shader = null;
}
get aoPassMap() {
return this._aoPassMap;
}
set aoPassMap( aoPassMap ) {
this._aoPassMap = aoPassMap;
this.needsUpdate = true;
this._setUniforms();
}
_customProgramCacheKey() {
return this._aoPassMap !== undefined && this._aoPassMap !== null ? 'aoPassMap' : '';
}
_onBeforeCompile( shader ) {
this._shader = shader;
if ( this._aoPassMap !== undefined && this._aoPassMap !== null ) {
shader.fragmentShader = shader.fragmentShader.replace(
'#include <aomap_pars_fragment>',
aomap_pars_fragment_replacement
);
shader.fragmentShader = shader.fragmentShader.replace(
'#include <aomap_fragment>',
aomap_fragment_replacement
);
}
this._setUniforms();
}
_setUniforms() {
if ( this._shader ) {
this._shader.uniforms.tAoPassMap = { value: this._aoPassMap };
this._shader.uniforms.aoPassMapScale = { value: this.aoPassMapScale };
}
}
}
const aomap_pars_fragment_replacement = /* glsl */`
#ifdef USE_AOMAP
uniform sampler2D aoMap;
uniform float aoMapIntensity;
#endif
uniform sampler2D tAoPassMap;
uniform float aoPassMapScale;
`;
const aomap_fragment_replacement = /* glsl */`
#ifndef AOPASSMAP_SWIZZLE
#define AOPASSMAP_SWIZZLE r
#endif
float ambientOcclusion = texelFetch( tAoPassMap, ivec2( gl_FragCoord.xy * aoPassMapScale ), 0 ).AOPASSMAP_SWIZZLE;
#ifdef USE_AOMAP
// reads channel R, compatible with a combined OcclusionRoughnessMetallic (RGB) texture
ambientOcclusion = min( ambientOcclusion, texture2D( aoMap, vAoMapUv ).r );
ambientOcclusion *= ( ambientOcclusion - 1.0 ) * aoMapIntensity + 1.0;
#endif
reflectedLight.indirectDiffuse *= ambientOcclusion;
#if defined( USE_CLEARCOAT )
clearcoatSpecularIndirect *= ambientOcclusion;
#endif
#if defined( USE_SHEEN )
sheenSpecularIndirect *= ambientOcclusion;
#endif
#if defined( USE_ENVMAP ) && defined( STANDARD )
float dotNV = saturate( dot( geometryNormal, geometryViewDir ) );
reflectedLight.indirectSpecular *= computeSpecularOcclusion( dotNV, ambientOcclusion, material.roughness );
#endif
`;
export { MeshPostProcessingMaterial };