optimize pssm split calculation

jme3-core/src/main/java/com/jme3/material/logic/ShadowStaticPassLightingLogic.java

@@ -187,7 +187,7 @@ public class ShadowStaticPassLightingLogic extends StaticPassLightingLogic {
         
         if (pssmSplits != null) {
             Uniform pssmSplitsUniform = shader.getUniform("g_PssmSplits");
-            pssmSplitsUniform.setValue(VarType.Vector4, pssmSplits);
+            pssmSplitsUniform.setValue(VarType.Vector3, pssmSplits);
         }
     }
 }

jme3-core/src/main/java/com/jme3/shadow/next/array/DirectionalArrayShadowMap.java

@@ -34,7 +34,6 @@ package com.jme3.shadow.next.array;
 import com.jme3.light.DirectionalLight;
 import com.jme3.light.Light;
 import com.jme3.math.Vector3f;
-import com.jme3.math.Vector4f;
 import com.jme3.renderer.RenderManager;
 import com.jme3.renderer.ViewPort;
 import com.jme3.renderer.queue.GeometryList;
@@ -47,7 +46,7 @@ import com.jme3.texture.TextureArray;
 public class DirectionalArrayShadowMap extends BaseArrayShadowMap<DirectionalArrayShadowMapSlice> {
 
     private final DirectionalLight light;
-    private final Vector4f projectionSplitPositions = new Vector4f();
+    private final Vector3f projectionSplitPositions = new Vector3f();
 
     public DirectionalArrayShadowMap(DirectionalLight light, TextureArray array, int firstArraySlice, int textureSize, int numSplits, Vector3f[] points) {
         super(array, firstArraySlice);
@@ -70,7 +69,7 @@ public class DirectionalArrayShadowMap extends BaseArrayShadowMap<DirectionalArr
         }
     }
 
-    public Vector4f getProjectionSplitPositions() {
+    public Vector3f getProjectionSplitPositions() {
         return projectionSplitPositions;
     }
 

jme3-core/src/main/java/com/jme3/shadow/next/pssm/DirectionalShadowParameters.java

@@ -31,6 +31,7 @@
  */
 package com.jme3.shadow.next.pssm;
 
+import com.jme3.math.Vector3f;
 import com.jme3.math.Vector4f;
 import com.jme3.renderer.Camera;
 import com.jme3.shadow.PssmShadowUtil;
@@ -45,7 +46,7 @@ public final class DirectionalShadowParameters implements ShadowParameters {
     private int numSplits = 4;
     protected float zFarOverride = 0;
     private float[] splitPositions = new float[numSplits + 1];
-    private final Vector4f projectionSplitPositions = new Vector4f();
+    private final Vector3f projectionSplitPositions = new Vector3f();
 
     public float getLambda() {
         return lambda;
@@ -69,7 +70,7 @@ public final class DirectionalShadowParameters implements ShadowParameters {
         return splitPositions;
     }
 
-    public Vector4f getProjectionSplitPositions() {
+    public Vector3f getProjectionSplitPositions() {
         return projectionSplitPositions;
     }
 
@@ -124,7 +125,7 @@ public final class DirectionalShadowParameters implements ShadowParameters {
 
         switch (splitPositions.length) {
             case 5:
-                projectionSplitPositions.w = 1.0f; // = viewCamera.getViewToProjectionZ(splitPositions[4]);
+//                projectionSplitPositions.w = 1.0f;
             case 4:
                 projectionSplitPositions.z = viewCamera.getViewToProjectionZ(splitPositions[3]);
             case 3:

jme3-core/src/main/resources/Common/ShaderLib/InPassShadows.glsl

@@ -27,22 +27,13 @@
         }
     #else
         uniform sampler2DArrayShadow g_ShadowMapArray;
-        uniform vec4 g_PssmSplits;
+        uniform vec3 g_PssmSplits;
 
         int pssmSliceOffset;
 
         void Shadow_ProcessPssmSlice() {
-            #ifdef NUM_PSSM_SPLITS
-                float z = gl_FragCoord.z;
-                if (z < g_PssmSplits[0]) {
-                    pssmSliceOffset = 0;
-                } else if (z < g_PssmSplits[1]) {
-                    pssmSliceOffset = 1;
-                } else if (z < g_PssmSplits[2]) {
-                    pssmSliceOffset = 2;
-                } else {
-                    pssmSliceOffset = 3;
-                }
+            #if defined(NUM_PSSM_SPLITS) && NUM_PSSM_SPLITS > 1
+                pssmSliceOffset = int(dot(step(g_PssmSplits.xyz, gl_FragCoord.zzz), vec3(1.0)));
             #else
                 pssmSliceOffset = 0;
             #endif