SL-17600 Proper irradiance probes.

4 files changed, 238 insertions, 24 deletions

diff --git a/indra/newview/app_settings/shaders/class1/interface/irradianceGenF.glsl b/indra/newview/app_settings/shaders/class1/interface/irradianceGenF.glsl
new file mode 100644
index 0000000000..2028509775
--- /dev/null
+++ b/indra/newview/app_settings/shaders/class1/interface/irradianceGenF.glsl
@@ -0,0 +1,99 @@
+/** 
+ * @file irradianceGenF.glsl
+ *
+ * $LicenseInfo:firstyear=2022&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2022, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+ 
+
+/*[EXTRA_CODE_HERE]*/
+
+
+#ifdef DEFINE_GL_FRAGCOLOR
+out vec4 frag_color;
+#else
+#define frag_color gl_FragColor
+#endif
+
+uniform samplerCubeArray   reflectionProbes;
+uniform int sourceIdx;
+
+VARYING vec3 vary_dir;
+
+// =============================================================================================================
+// Parts of this file are (c) 2018 Sascha Willems
+// SNIPPED FROM https://github.com/SaschaWillems/Vulkan-glTF-PBR/blob/master/data/shaders/irradiancecube.frag
+/*
+MIT License
+
+Copyright (c) 2018 Sascha Willems
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+// =============================================================================================================
+
+
+
+#define PI 3.1415926535897932384626433832795
+
+float deltaPhi = PI/16.0;
+float deltaTheta = deltaPhi*0.25;
+
+void main()
+{
+	vec3 N = normalize(vary_dir);
+	vec3 up = vec3(0.0, 1.0, 0.0);
+	vec3 right = normalize(cross(up, N));
+	up = cross(N, right);
+
+	const float TWO_PI = PI * 2.0;
+	const float HALF_PI = PI * 0.5;
+
+	vec3 color = vec3(0.0);
+	uint sampleCount = 0u;
+	for (float phi = 0.0; phi < TWO_PI; phi += deltaPhi) {
+		for (float theta = 0.0; theta < HALF_PI; theta += deltaTheta) {
+			vec3 tempVec = cos(phi) * right + sin(phi) * up;
+			vec3 sampleVector = cos(theta) * N + sin(theta) * tempVec;
+			color += textureLod(reflectionProbes, vec4(sampleVector, sourceIdx), 3).rgb * cos(theta) * sin(theta);
+			sampleCount++;
+		}
+	}
+	frag_color = vec4(PI * color / float(sampleCount), 1.0);
+}
+// =============================================================================================================
+
diff --git a/indra/newview/app_settings/shaders/class1/interface/irradianceGenV.glsl b/indra/newview/app_settings/shaders/class1/interface/irradianceGenV.glsl
new file mode 100644
index 0000000000..5190abf17c
--- /dev/null
+++ b/indra/newview/app_settings/shaders/class1/interface/irradianceGenV.glsl
@@ -0,0 +1,38 @@
+/** 
+ * @file irradianceGenV.glsl
+ *
+ * $LicenseInfo:firstyear=2022&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2011, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+uniform mat4 modelview_matrix;
+
+ATTRIBUTE vec3 position;
+
+VARYING vec3 vary_dir;
+
+void main()
+{
+	gl_Position = vec4(position, 1.0);
+
+	vary_dir = vec3(modelview_matrix * vec4(position, 1.0)).xyz;
+}
+
diff --git a/indra/newview/app_settings/shaders/class1/interface/radianceGenF.glsl b/indra/newview/app_settings/shaders/class1/interface/radianceGenF.glsl
index 27008b8a1c..3fc227eae7 100644
--- a/indra/newview/app_settings/shaders/class1/interface/radianceGenF.glsl
+++ b/indra/newview/app_settings/shaders/class1/interface/radianceGenF.glsl
@@ -26,8 +26,6 @@
 
 /*[EXTRA_CODE_HERE]*/
 
-#define REFMAP_COUNT 256
-
 #ifdef DEFINE_GL_FRAGCOLOR
 out vec4 frag_color;
 #else
@@ -35,6 +33,7 @@ out vec4 frag_color;
 #endif
 
 uniform samplerCubeArray   reflectionProbes;
+uniform int sourceIdx;
 
 VARYING vec3 vary_dir;
 
@@ -150,7 +149,7 @@ vec3 prefilterEnvMap(vec3 R, float roughness)
 			float omegaP = 4.0 * PI / (6.0 * envMapDim * envMapDim);
 			// Biased (+1.0) mip level for better result
 			float mipLevel = roughness == 0.0 ? 0.0 : max(0.5 * log2(omegaS / omegaP) + 1.0, 0.0f);
-			color += textureLod(reflectionProbes, vec4(L,REFMAP_COUNT), mipLevel).rgb * dotNL;
+			color += textureLod(reflectionProbes, vec4(L,sourceIdx), mipLevel).rgb * dotNL;
 			totalWeight += dotNL;
 
 		}
diff --git a/indra/newview/app_settings/shaders/class3/deferred/reflectionProbeF.glsl b/indra/newview/app_settings/shaders/class3/deferred/reflectionProbeF.glsl
index 40378b49ea..83348077d7 100644
--- a/indra/newview/app_settings/shaders/class3/deferred/reflectionProbeF.glsl
+++ b/indra/newview/app_settings/shaders/class3/deferred/reflectionProbeF.glsl
@@ -31,6 +31,7 @@
 #define REF_SAMPLE_COUNT 64 //maximum number of samples to consider
 
 uniform samplerCubeArray   reflectionProbes;
+uniform samplerCubeArray   irradianceProbes;
 
 layout (std140, binding = 1) uniform ReflectionProbes
 {
@@ -308,7 +309,7 @@ vec3 boxIntersect(vec3 origin, vec3 dir, int i)
 
 
 
-// Tap a sphere based reflection probe
+// Tap a reflection probe
 // pos - position of pixel
 // dir - pixel normal
 // lod - which mip to bias towards (lower is higher res, sharper reflections)
@@ -334,10 +335,36 @@ vec3 tapRefMap(vec3 pos, vec3 dir, float lod, vec3 c, float r2, int i)
     v -= c;
     v = env_mat * v;
     {
-        //float min_lod = textureQueryLod(reflectionProbes,v).y; // lower is higher res
-        //return textureLod(reflectionProbes, vec4(v.xyz, refIndex[i].x), max(min_lod, lod)).rgb;
         return textureLod(reflectionProbes, vec4(v.xyz, refIndex[i].x), lod).rgb;
-        //return texture(reflectionProbes, vec4(v.xyz, refIndex[i].x)).rgb;
+    }
+}
+
+// Tap an irradiance map
+// pos - position of pixel
+// dir - pixel normal
+// c - center of probe
+// r2 - radius of probe squared
+// i - index of probe 
+// vi - point at which reflection vector struck the influence volume, in clip space
+vec3 tapIrradianceMap(vec3 pos, vec3 dir, vec3 c, float r2, int i)
+{
+    //lod = max(lod, 1);
+    // parallax adjustment
+
+    vec3 v;
+    if (refIndex[i].w < 0)
+    {
+        v = boxIntersect(pos, dir, i);
+    }
+    else
+    {
+        v = sphereIntersect(pos, dir, c, r2);
+    }
+
+    v -= c;
+    v = env_mat * v;
+    {
+        return texture(irradianceProbes, vec4(v.xyz, refIndex[i].x)).rgb * refParams[i].x;
     }
 }
 
@@ -371,7 +398,7 @@ vec3 sampleProbes(vec3 pos, vec3 dir, float lod, float minweight)
             float atten = 1.0-max(d2-r2, 0.0)/(rr-r2);
             w *= atten;
             //w *= p; // boost weight based on priority
-            col += refcol*w*max(minweight, refParams[i].x);
+            col += refcol*w;
             
             wsum += w;
         }
@@ -394,7 +421,7 @@ vec3 sampleProbes(vec3 pos, vec3 dir, float lod, float minweight)
                 
                 float w = 1.0/d2;
                 w *= w;
-                col += refcol*w*max(minweight, refParams[i].x);
+                col += refcol*w;
                 wsum += w;
             }
         }
@@ -408,24 +435,75 @@ vec3 sampleProbes(vec3 pos, vec3 dir, float lod, float minweight)
     return col;
 }
 
-vec3 sampleProbeAmbient(vec3 pos, vec3 dir, float lod)
+vec3 sampleProbeAmbient(vec3 pos, vec3 dir)
 {
-    vec3 col = sampleProbes(pos, dir, lod, 0.f);
+    // modified copy/paste of sampleProbes follows, will likely diverge from sampleProbes further
+    // as irradiance map mixing is tuned independently of radiance map mixing
+    float wsum = 0.0;
+    vec3 col = vec3(0,0,0);
+    float vd2 = dot(pos,pos); // view distance squared
 
-    //desaturate
-    vec3 hcol = col *0.5;
-    
-    col *= 2.0;
-    col = vec3(
-        col.r + hcol.g + hcol.b,
-        col.g + hcol.r + hcol.b,
-        col.b + hcol.r + hcol.g
-    );
-    
-    col *= 0.333333;
+    float minweight = 1.0;
 
-    return col;
+    for (int idx = 0; idx < probeInfluences; ++idx)
+    {
+        int i = probeIndex[idx];
+        if (abs(refIndex[i].w) < max_priority)
+        {
+            continue;
+        }
+        float r = refSphere[i].w; // radius of sphere volume
+        float p = float(abs(refIndex[i].w)); // priority
+        
+        float rr = r*r; // radius squred
+        float r1 = r * 0.1; // 75% of radius (outer sphere to start interpolating down)
+        vec3 delta = pos.xyz-refSphere[i].xyz;
+        float d2 = dot(delta,delta);
+        float r2 = r1*r1; 
+        
+        {
+            vec3 refcol = tapIrradianceMap(pos, dir, refSphere[i].xyz, rr, i);
+            
+            float w = 1.0/d2;
+
+            float atten = 1.0-max(d2-r2, 0.0)/(rr-r2);
+            w *= atten;
+            //w *= p; // boost weight based on priority
+            col += refcol*w;
+            
+            wsum += w;
+        }
+    }
 
+    if (probeInfluences <= 1)
+    { //edge-of-scene probe or no probe influence, mix in with embiggened version of probes closest to camera 
+        for (int idx = 0; idx < 8; ++idx)
+        {
+            if (refIndex[idx].w < 0)
+            { // don't fallback to box probes, they are *very* specific
+                continue;
+            }
+            int i = idx;
+            vec3 delta = pos.xyz-refSphere[i].xyz;
+            float d2 = dot(delta,delta);
+            
+            {
+                vec3 refcol = tapIrradianceMap(pos, dir, refSphere[i].xyz, d2, i);
+                
+                float w = 1.0/d2;
+                w *= w;
+                col += refcol*w;
+                wsum += w;
+            }
+        }
+    }
+
+    if (wsum > 0.0)
+    {
+        col *= 1.0/wsum;
+    }
+    
+    return col;
 }
 
 // brighten a color so that at least one component is 1
@@ -451,7 +529,7 @@ void sampleReflectionProbes(inout vec3 ambenv, inout vec3 glossenv, inout vec3 l
 
     vec3 refnormpersp = reflect(pos.xyz, norm.xyz);
 
-    ambenv = sampleProbeAmbient(pos, norm, reflection_lods-2);
+    ambenv = sampleProbeAmbient(pos, norm);
 
     if (glossiness > 0.0)
     {