Add pcf for spotshadows

h3d/pass/SpotShadowMap.hx

@@ -12,7 +12,7 @@ class SpotShadowMap extends Shadows {
 		super(light);
 		lightCamera = new h3d.Camera();
 		lightCamera.screenRatio = 1.0;
-		lightCamera.zNear = 3.0;
+		lightCamera.zNear = 0.01;
 		shader = sshader = new h3d.shader.SpotShadow();
 		border = new Border(size, size);
 		customDepth = h3d.Engine.getCurrent().driver.hasFeature(AllocDepthBuffer);
@@ -56,6 +56,9 @@ class SpotShadowMap extends Shadows {
 		sshader.shadowBias = bias;
 		sshader.shadowPower = power;
 		sshader.shadowProj = getShadowProj();
+		sshader.shadowRes.set(texture.width,texture.height);
+		sshader.pcfScale = pcfScale;
+		sshader.PCF = pcf;
 	}
 
 	override function saveStaticData() {

h3d/shader/SpotShadow.hx

@@ -6,23 +6,93 @@ class SpotShadow extends hxsl.Shader {
 
 		@const var enable : Bool;
 
+		@const var PCF : Int;
+		@param var pcfScale : Float;
+
 		@param var shadowMap : Channel;
 		@param var shadowProj : Mat4;
 		@param var shadowPower : Float;
 		@param var shadowBias : Float;
+		@param var shadowRes : Vec2;
 
 		var transformedPosition : Vec3;
 		var shadow : Float;
 
+		@param var poissonDisk2x2 : Array<Vec4,5>;
+		@param var poissonDisk4x4 : Array<Vec4,13>;
+
+		function rand( v : Float ) : Float {
+			 var dp = dot(vec4(v), vec4(12.9898,78.233,45.164,94.673));
+   			 return fract(sin(dp) * 43758.5453);
+		}
+
 		function fragment() {
 			if( enable ) {
-				var shadowPos = vec4(transformedPosition, 1.0) * shadowProj;
-				var shadowScreenPos = shadowPos.xyz / shadowPos.w;
-				var depth = shadowMap.get(screenToUv(shadowScreenPos.xy));
-				var zMax = shadowScreenPos.z.saturate();
-				var delta = (depth + shadowBias).min(zMax) - zMax;
-				shadow = exp( shadowPower * delta ).saturate();
+				if( PCF > 0 ) {
+					shadow = 1.0;
+					var texelSize = 1.0/shadowRes;
+					var shadowPos = vec4(transformedPosition, 1.0) * shadowProj;
+					shadowPos.xyz = shadowPos.xyz / shadowPos.w;
+					var shadowUv = screenToUv( shadowPos.xy );
+					var zMax = shadowPos.z.saturate();
+
+					var rot = rand(transformedPosition.x + transformedPosition.y + transformedPosition.z) * 3.14 * 2;
+					switch(PCF){
+						case 1:
+							var sampleStrength = 1.0 / 5.0;
+							for( i in 0 ... 5 ) {
+								var offset = poissonDisk2x2[i].xy * texelSize * pcfScale;
+								offset = vec2(cos(rot) * offset.x - sin(rot) * offset.y, cos(rot) * offset.y + sin(rot) * offset.x);
+								var depth = shadowMap.get(shadowUv + offset);
+								if( zMax - shadowBias > depth )
+									shadow -= sampleStrength;
+							}
+						case 2:
+							var sampleStrength = 1.0 / 13.0;
+							for( i in 0 ... 13 ) {
+								var offset = poissonDisk4x4[i].xy * texelSize * pcfScale;
+								offset = vec2(cos(rot) * offset.x - sin(rot) * offset.y, cos(rot) * offset.y + sin(rot) * offset.x);
+								var depth = shadowMap.get(shadowUv + offset);
+								if( zMax - shadowBias > depth )
+									shadow -= sampleStrength;
+							}
+					}
+				}
+				else{
+					var shadowPos = vec4(transformedPosition, 1.0) * shadowProj;
+					var shadowScreenPos = shadowPos.xyz / shadowPos.w;
+					var depth = shadowMap.get(screenToUv(shadowScreenPos.xy));
+					var zMax = shadowScreenPos.z.saturate();
+					var delta = (depth + shadowBias).min(zMax) - zMax;
+					shadow = exp( shadowPower * delta ).saturate();
+				}
 			}
 		}
+
 	}
-}
+
+	public function new() {
+		super();
+		poissonDisk2x2 = [	new h3d.Vector( 0., 0. ),
+							new h3d.Vector(-0.942,-0.399 ),
+							new h3d.Vector( 0.945,-0.768 ),
+							new h3d.Vector(-0.094,-0.929 ),
+							new h3d.Vector( 0.344, 0.293 ) ];
+
+		poissonDisk4x4 = [  new h3d.Vector( 0., 0. ),
+							new h3d.Vector(-0.326,-0.406),
+							new h3d.Vector(-0.840,-0.074),
+							new h3d.Vector(-0.696, 0.457),
+							new h3d.Vector(-0.203, 0.621),
+							new h3d.Vector( 0.962,-0.195),
+							new h3d.Vector( 0.473,-0.480),
+							new h3d.Vector( 0.519, 0.767),
+							new h3d.Vector( 0.185,-0.893),
+							new h3d.Vector( 0.507, 0.064),
+							new h3d.Vector( 0.896, 0.412),
+							new h3d.Vector(-0.322,-0.933),
+							new h3d.Vector(-0.792,-0.598) ];
+
+	}
+}
+