Added PCFSoftShadowMapFast for better looking shadows on low powered devices

src/constants.js

@@ -9,6 +9,7 @@ export var FrontFaceDirectionCCW = 1;
 export var BasicShadowMap = 0;
 export var PCFShadowMap = 1;
 export var PCFSoftShadowMap = 2;
+export var PCFSoftShadowMapFast = 3;
 export var FrontSide = 0;
 export var BackSide = 1;
 export var DoubleSide = 2;

src/renderers/shaders/ShaderChunk/shadowmap_pars_fragment.glsl.js

@@ -119,6 +119,39 @@ export default /* glsl */`
 				texture2DShadowLerp( shadowMap, shadowMapSize, shadowCoord.xy + vec2( dx1, dy1 ), shadowCoord.z )
 			) * ( 1.0 / 9.0 );
 
+		#elif defined( SHADOWMAP_TYPE_PCF_SOFT_FAST )
+
+			vec2 texelSize = vec2( 1.0 ) / shadowMapSize;
+
+			float dx0 = - texelSize.x * shadowRadius;
+			float dy0 = - texelSize.y * shadowRadius;
+			float dx1 = + texelSize.x * shadowRadius;
+			float dy1 = + texelSize.y * shadowRadius;
+			float dx2 = dx0 / 2.0;
+			float dy2 = dy0 / 2.0;
+			float dx3 = dx1 / 2.0;
+			float dy3 = dy1 / 2.0;
+
+			shadow = (
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx0, dy0 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( 0.0, dy0 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx1, dy0 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx2, dy2 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( 0.0, dy2 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx3, dy2 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx0, 0.0 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx2, 0.0 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy, shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx3, 0.0 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx1, 0.0 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx2, dy3 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( 0.0, dy3 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx3, dy3 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx0, dy1 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( 0.0, dy1 ), shadowCoord.z ) +
+				texture2DCompare( shadowMap, shadowCoord.xy + vec2( dx1, dy1 ), shadowCoord.z )
+			) * ( 1.0 / 17.0 );
+
 		#else // no percentage-closer filtering:
 
 			shadow = texture2DCompare( shadowMap, shadowCoord.xy, shadowCoord.z );

src/renderers/webgl/WebGLProgram.js

@@ -5,7 +5,7 @@
 import { WebGLUniforms } from './WebGLUniforms.js';
 import { WebGLShader } from './WebGLShader.js';
 import { ShaderChunk } from '../shaders/ShaderChunk.js';
-import { NoToneMapping, AddOperation, MixOperation, MultiplyOperation, EquirectangularRefractionMapping, CubeRefractionMapping, SphericalReflectionMapping, EquirectangularReflectionMapping, CubeUVRefractionMapping, CubeUVReflectionMapping, CubeReflectionMapping, PCFSoftShadowMap, PCFShadowMap, ACESFilmicToneMapping, CineonToneMapping, Uncharted2ToneMapping, ReinhardToneMapping, LinearToneMapping, GammaEncoding, RGBDEncoding, RGBM16Encoding, RGBM7Encoding, RGBEEncoding, sRGBEncoding, LinearEncoding } from '../../constants.js';
+import { NoToneMapping, AddOperation, MixOperation, MultiplyOperation, EquirectangularRefractionMapping, CubeRefractionMapping, SphericalReflectionMapping, EquirectangularReflectionMapping, CubeUVRefractionMapping, CubeUVReflectionMapping, CubeReflectionMapping, PCFSoftShadowMapFast, PCFSoftShadowMap, PCFShadowMap, ACESFilmicToneMapping, CineonToneMapping, Uncharted2ToneMapping, ReinhardToneMapping, LinearToneMapping, GammaEncoding, RGBDEncoding, RGBM16Encoding, RGBM7Encoding, RGBEEncoding, sRGBEncoding, LinearEncoding } from '../../constants.js';
 
 var programIdCount = 0;
 
@@ -225,6 +225,10 @@ function WebGLProgram( renderer, extensions, code, material, shader, parameters,
 
 		shadowMapTypeDefine = 'SHADOWMAP_TYPE_PCF_SOFT';
 
+	} else if ( parameters.shadowMapType === PCFSoftShadowMapFast ) {
+
+		shadowMapTypeDefine = 'SHADOWMAP_TYPE_PCF_SOFT_FAST';
+
 	}
 
 	var envMapTypeDefine = 'ENVMAP_TYPE_CUBE';