Added percentage-close filtering to shadow map shader.

Nine tap sampling, by default it's on, switch off with:

renderer.shadowMapSoft = false;

src/renderers/WebGLRenderer.js

@@ -105,6 +105,7 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 	this.shadowMap = [];
 	this.shadowMapEnabled = false;
+	this.shadowMapSoft = true;
 
 	var _cameraLight,
 		_shadowMatrix = [];
@@ -2646,6 +2647,9 @@ THREE.WebGLRenderer = function ( parameters ) {
 			maxDirLights: maxLightCount.directional, maxPointLights: maxLightCount.point,
 			maxBones: maxBones,
 			shadowMapEnabled: this.shadowMapEnabled && object.receiveShadow,
+			shadowMapSoft: this.shadowMapSoft,
+			shadowMapWidth: this.shadowMapWidth,
+			shadowMapHeight: this.shadowMapHeight,
 			maxShadows: maxShadows
 
 		};
@@ -5070,7 +5074,9 @@ THREE.WebGLRenderer = function ( parameters ) {
 			parameters.vertexColors ? "#define USE_COLOR" : "",
 			parameters.skinning ? "#define USE_SKINNING" : "",
 			parameters.morphTargets ? "#define USE_MORPHTARGETS" : "",
+
 			parameters.shadowMapEnabled ? "#define USE_SHADOWMAP" : "",
+			parameters.shadowMapSoft ? "#define SHADOWMAP_SOFT" : "",
 
 			parameters.sizeAttenuation ? "#define USE_SIZEATTENUATION" : "",
 
@@ -5138,7 +5144,11 @@ THREE.WebGLRenderer = function ( parameters ) {
 			parameters.envMap ? "#define USE_ENVMAP" : "",
 			parameters.lightMap ? "#define USE_LIGHTMAP" : "",
 			parameters.vertexColors ? "#define USE_COLOR" : "",
+
 			parameters.shadowMapEnabled ? "#define USE_SHADOWMAP" : "",
+			parameters.shadowMapSoft ? "#define SHADOWMAP_SOFT" : "",
+			parameters.shadowMapSoft ? "#define SHADOWMAP_WIDTH " + parameters.shadowMapWidth.toFixed( 1 ) : "",
+			parameters.shadowMapSoft ? "#define SHADOWMAP_HEIGHT " + parameters.shadowMapHeight.toFixed( 1 ) : "",
 
 			"uniform mat4 viewMatrix;",
 			"uniform vec3 cameraPosition;",

src/renderers/WebGLShaders.js

@@ -559,22 +559,63 @@ THREE.ShaderChunk = {
 
 	"#ifdef USE_SHADOWMAP",
 
+		"#ifdef SHADOWMAP_SOFT",
+
+			"const float xPixelOffset = 1.0 / SHADOWMAP_WIDTH;",
+			"const float yPixelOffset = 1.0 / SHADOWMAP_HEIGHT;",
+
+		"#endif",
+
 		"vec4 shadowColor = vec4( 1.0 );",
 
 		"for( int i = 0; i < MAX_SHADOWS; i ++ ) {",
 
 			"vec3 shadowCoord = vShadowCoord[ i ].xyz / vShadowCoord[ i ].w;",
 
-			"vec4 rgbaDepth = texture2D( shadowMap[ i ], shadowCoord.xy );",
-			"float fDepth = unpackDepth( rgbaDepth );",
+			"if ( shadowCoord.x >= 0.0 && shadowCoord.x <= 1.0 && shadowCoord.y >= 0.0 && shadowCoord.y <= 1.0 ) {",
+
+				"#ifdef SHADOWMAP_SOFT",
+
+					// Percentage-close filtering
+					// (9 pixel kernel)
+					// http://fabiensanglard.net/shadowmappingPCF/
+
+					"float shadow = 0.0;",
 
-			"if ( fDepth < ( shadowCoord.z + shadowBias ) && ( shadowCoord.x >= 0.0 && shadowCoord.x <= 1.0 && shadowCoord.y >= 0.0 && shadowCoord.y <= 1.0 ) )",
+					"for ( float y = -1.25; y <= 1.25; y += 1.25 )",
+						"for ( float x = -1.25; x <= 1.25; x += 1.25 ) {",
 
-				// spot with multiple shadows is darker
-				"shadowColor = shadowColor * vec4( vec3( shadowDarkness ), 1.0 );",
+							"vec4 rgbaDepth = texture2D( shadowMap[ i ], vec2( x * xPixelOffset, y * yPixelOffset ) + shadowCoord.xy );",
+							"float fDepth = unpackDepth( rgbaDepth );",
+
+							"if ( fDepth < ( shadowCoord.z + shadowBias ) )",
+								"shadow += 1.0;",
+
+					"}",
+
+					"shadow /= 9.0;",
+
+					"shadowColor = shadowColor * vec4( vec3( ( 1.0 - shadowDarkness * shadow ) ), 1.0 );",
+
+				"#else",
+
+					"vec4 rgbaDepth = texture2D( shadowMap[ i ], shadowCoord.xy );",
+					"float fDepth = unpackDepth( rgbaDepth );",
+
+					"if ( fDepth < ( shadowCoord.z + shadowBias ) )",
+
+						// spot with multiple shadows is darker
+
+						"shadowColor = shadowColor * vec4( vec3( shadowDarkness ), 1.0 );",
+
+						// spot with multiple shadows has the same color as single shadow spot
+
+						//"shadowColor = min( shadowColor, vec4( vec3( shadowDarkness ), 1.0 ) );",
+
+				"#endif",
+
+			"}",
 
-				// spot with multiple shadows has the same color as single shadow spot
-				//"shadowColor = min( shadowColor, vec4( vec3( shadowDarkness ), 1.0 ) );",
 
 			// uncomment to see light frustum boundaries
 			//"if ( !( shadowCoord.x >= 0.0 && shadowCoord.x <= 1.0 && shadowCoord.y >= 0.0 && shadowCoord.y <= 1.0 ) )",
@@ -1045,7 +1086,7 @@ THREE.ShaderLib = {
 			"void main() {",
 
 				"vec4 pos      = objectMatrix * vec4( position, 1.0 );",
-				"vec3 norm     = mat3( objectMatrix[0].xyz, objectMatrix[1].xyz, objectMatrix[2].xyz ) * normal;",
+				"vec3 norm     = mat3( objectMatrix[ 0 ].xyz, objectMatrix[ 1 ].xyz, objectMatrix[ 2 ].xyz ) * normal;",
 				"vec4 extruded = vec4( directionalLightDirection * 5000.0 * step( 0.0, dot( directionalLightDirection, norm ) ), 0.0 );",
 
 				"gl_Position   = projectionMatrix * viewMatrix * ( pos + extruded );",
@@ -1359,7 +1400,9 @@ THREE.ShaderLib = {
 				THREE.ShaderChunk[ "color_vertex" ],
 
 				"#ifndef USE_ENVMAP",
+
 					"vec4 mPosition = objectMatrix * vec4( position, 1.0 );",
+
 				"#endif",
 
 				"vViewPosition = cameraPosition - mPosition.xyz;",