some tuning for vsm fog

#681

game/graphics/drawcommands.cpp

@@ -238,15 +238,14 @@ void DrawCommands::updateTasksUniforms() {
     i.desc.set(T_Clusters, clusters.ssbo());
     i.desc.set(T_Indirect, views[i.viewport].indirectCmd);
     i.desc.set(T_Payload,  views[i.viewport].visClusters);
+    i.desc.set(T_Scene,    scene.uboGlobal[i.viewport]);
+    i.desc.set(T_Instance, owner.instanceSsbo());
+    i.desc.set(T_Bucket,   buckets.ssbo());
 
     if(i.viewport!=SceneGlobals::V_Vsm) {
-      i.desc.set(T_Scene,    scene.uboGlobal[i.viewport]);
-      i.desc.set(T_Instance, owner.instanceSsbo());
-      i.desc.set(T_Bucket,   buckets.ssbo());
       i.desc.set(T_HiZ,      *scene.hiZ);
       } else {
-      i.desc.set(T_Scene,    scene.uboGlobal[i.viewport]);
-      i.desc.set(T_Payload,  views[i.viewport].vsmClusters);
+      i.desc.set(T_Payload,  views[i.viewport].vsmClusters); //unsorted clusters
       i.desc.set(T_HiZ,      *scene.vsmPageHiZ);
       i.desc.set(T_VsmPages, *scene.vsmPageList);
       i.desc.set(8,          scene.vsmDbg);

game/graphics/renderer.cpp

@@ -147,7 +147,7 @@ void Renderer::resetSwapchain() {
       if(settings.vsmEnabled && (i+1)!=Resources::ShadowLayers)
         continue;
       if(settings.vsmEnabled && !settings.giEnabled)
-        continue; //TODO: support vsm in gi code
+        ;//continue; //TODO: support vsm in gi code
       shadowMap[i] = device.zbuffer(shadowFormat,smSize,smSize);
       }
     }
@@ -486,6 +486,7 @@ void Renderer::prepareUniforms() {
     if(!vsm.pageDataCs.isEmpty())
       vsm.uboLight.set(6, vsm.pageDataCs); else
       vsm.uboLight.set(6, vsm.pageData);
+    vsm.uboLight.set(8, wview->sceneGlobals().vsmDbg);
 
     vsm.uboReproj.set(0, wview->sceneGlobals().uboGlobal[SceneGlobals::V_Main]);
     vsm.uboReproj.set(1, vsm.pageTbl);
@@ -878,7 +879,7 @@ void Renderer::drawVsm(Tempest::Encoder<Tempest::CommandBuffer>& cmd, uint8_t fI
   cmd.dispatchThreads(zbuffer.size());
 
   // sky&fog
-  if(wview.sky().isVolumetric()) {
+  if(true && wview.sky().isVolumetric()) {
     cmd.setUniforms(shaders.vsmMarkFogPages, vsm.uboPages);
     cmd.dispatchThreads(zbuffer.size());
     // wview.vsmMarkSkyPages(cmd, fId);

game/graphics/renderer.h

@@ -88,7 +88,7 @@ class Renderer final {
 
       float          vidResIndex        = 0;
 
-      float          vsmMipBias         = -0.25;
+      float          vsmMipBias         = 0.25; //TODO: set to lower, eventually
       } settings;
 
     Frustrum                  frustrum[SceneGlobals::V_Count];

game/graphics/sceneglobals.cpp

@@ -32,7 +32,7 @@ SceneGlobals::SceneGlobals() {
   vsmPageData = &Resources::fallbackBlack();
   vsmPageTbl  = &Resources::fallbackImage3d();
   vsmPageHiZ  = &Resources::fallbackImage3d();
-  vsmDbg      = device.image2d(Tempest::TextureFormat::R32U, 32, 32);
+  vsmDbg      = device.image2d(Tempest::TextureFormat::R32U, 64, 64);
 
   for(uint8_t lay=0; lay<V_Count; ++lay) {
     uboGlobal[lay] = device.ssbo(nullptr,sizeof(UboGlobal));

game/graphics/shaders.cpp

@@ -201,7 +201,6 @@ Shaders::Shaders() {
     vsmClearPages   = computeShader("vsm_clear_pages.comp.sprv");
     vsmMarkPages    = computeShader("vsm_mark_pages.comp.sprv");
     vsmMarkFogPages = computeShader("vsm_mark_fog_pages.comp.sprv");
-    vsmMarkSky      = computeShader("fog3d_vsm_mark_pages.comp.sprv");
     vsmTrimPages    = computeShader("vsm_trim_pages.comp.sprv");
     vsmClumpPages   = computeShader("vsm_clump_pages.comp.sprv");
     vsmListPages    = computeShader("vsm_list_pages.comp.sprv");

game/graphics/shaders.h

@@ -76,7 +76,7 @@ class Shaders {
 
     // Virtual shadow
     Tempest::ComputePipeline vsmClusterTask;
-    Tempest::ComputePipeline vsmClear, vsmClearPages, vsmMarkPages, vsmMarkFogPages, vsmMarkSky;
+    Tempest::ComputePipeline vsmClear, vsmClearPages, vsmMarkPages, vsmMarkFogPages;
     Tempest::ComputePipeline vsmTrimPages, vsmListPages, vsmClumpPages, vsmAllocPages, vsmMergePages;
     Tempest::ComputePipeline vsmPackDraw0, vsmPackDraw1;
     Tempest::RenderPipeline  vsmDirectLight;

game/graphics/sky/sky.cpp

@@ -373,15 +373,6 @@ void Sky::prepareUniforms() {
       uboOcclusion.set(4, *scene.shadowMap[1], Resources::shadowSampler());
       }
 
-    if(quality==VolumetricHQVsm) {
-      uboVsmPages = device.descriptors(Shaders::inst().vsmMarkSky);
-      uboVsmPages.set(1, *scene.zbuffer, Sampler::nearest());
-      uboVsmPages.set(2, scene.uboGlobal[SceneGlobals::V_Main]);
-      uboVsmPages.set(3, occlusionLut);
-      uboVsmPages.set(4, *scene.vsmPageTbl);
-      uboVsmPages.set(5, *scene.vsmPageHiZ);
-      }
-
     uboFogViewLut3d = device.descriptors(Shaders::inst().fogViewLut3d);
     uboFogViewLut3d.set(0, scene.uboGlobal[SceneGlobals::V_Main]);
     uboFogViewLut3d.set(1, transLut,     smpB);
@@ -459,17 +450,6 @@ void Sky::prepareSky(Tempest::Encoder<Tempest::CommandBuffer>& cmd, uint32_t fra
   cmd.draw(Resources::fsqVbo());
   }
 
-void Sky::vsmMarkPage(Tempest::Encoder<Tempest::CommandBuffer>& cmd, uint32_t frameId) {
-  if(quality!=VolumetricHQVsm)
-    return;
-
-  UboSky ubo = mkPush();
-  auto& vsmMarkSky = Shaders::inst().vsmMarkSky;
-  cmd.setFramebuffer({});
-  cmd.setUniforms(vsmMarkSky, uboVsmPages, &ubo, sizeof(ubo));
-  cmd.dispatchThreads(occlusionLut.size());
-  }
-
 void Sky::prepareFog(Tempest::Encoder<Tempest::CommandBuffer>& cmd, uint32_t frameId) {
   UboSky ubo = mkPush();
 

game/graphics/sky/sky.h

@@ -22,7 +22,6 @@ class Sky final {
     void updateLight(const int64_t now);
 
     void prepareSky (Tempest::Encoder<Tempest::CommandBuffer>& p, uint32_t frameId);
-    void vsmMarkPage(Tempest::Encoder<Tempest::CommandBuffer>& p, uint32_t frameId);
     void drawSky    (Tempest::Encoder<Tempest::CommandBuffer>& p, uint32_t frameId);
     void drawSunMoon(Tempest::Encoder<Tempest::CommandBuffer>& p, uint32_t frameId);
 
@@ -84,7 +83,6 @@ class Sky final {
     Tempest::DescriptorSet        uboFogViewLut3d;
     Tempest::DescriptorSet        uboSky, uboFog, uboFog3d;
     Tempest::DescriptorSet        uboOcclusion, uboShadowRq;
-    Tempest::DescriptorSet        uboVsmPages;
     Tempest::DescriptorSet        uboIrradiance, uboExp;
 
     Tempest::DescriptorSet        uboSkyPathtrace;

game/graphics/worldview.cpp

@@ -127,10 +127,6 @@ void WorldView::prepareExposure(Tempest::Encoder<Tempest::CommandBuffer>& cmd, u
   gSky.prepareExposure(cmd, frameId);
   }
 
-void WorldView::vsmMarkSkyPages(Tempest::Encoder<Tempest::CommandBuffer>& cmd, uint8_t frameId) {
-  gSky.vsmMarkPage(cmd, frameId);
-  }
-
 void WorldView::updateFrustrum(const Frustrum fr[]) {
   for(uint8_t i=0; i<SceneGlobals::V_Count; ++i)
     sGlobal.frustrum[i] = fr[i];

game/graphics/worldview.h

@@ -55,8 +55,6 @@ class WorldView {
     void prepareIrradiance(Tempest::Encoder<Tempest::CommandBuffer> &cmd, uint8_t frameId);
     void prepareExposure  (Tempest::Encoder<Tempest::CommandBuffer> &cmd, uint8_t frameId);
 
-    void vsmMarkSkyPages  (Tempest::Encoder<Tempest::CommandBuffer> &cmd, uint8_t frameId);
-
     bool updateLights();
     bool updateRtScene();
 

shader/CMakeLists.txt

@@ -237,7 +237,6 @@ add_shader(clouds_lut.comp           sky/clouds_lut.comp)
 add_shader(fog_view_lut.comp         sky/fog_view_lut.comp)
 
 add_shader(fog3d.comp                sky/fog.frag -S comp -DVOLUMETRIC)
-add_shader(fog3d_vsm_mark_pages.comp sky/fog.frag -S comp -DVOLUMETRIC -DVIRTUAL_SHADOW_MARK)
 add_shader(fog3d_vsm.comp            sky/fog.frag -S comp -DVOLUMETRIC -DVIRTUAL_SHADOW)
 add_shader(fog3d_hq.frag             sky/fog.frag -DVOLUMETRIC)
 add_shader(fog.frag                  sky/fog.frag)

shader/sky/fog.frag

@@ -3,7 +3,7 @@
 #extension GL_GOOGLE_include_directive    : enable
 #extension GL_EXT_control_flow_attributes : enable
 
-#if defined(VIRTUAL_SHADOW) || defined(VIRTUAL_SHADOW_MARK)
+#if defined(VIRTUAL_SHADOW)
 #include "virtual_shadow/vsm_common.glsl"
 #endif
 
@@ -37,15 +37,10 @@ layout(binding = 3, r32ui) uniform writeonly restrict uimage2D occlusionLut;
 layout(binding = 3, r32ui) uniform readonly  restrict uimage2D occlusionLut;
 #endif
 
-#if defined(VOLUMETRIC) && !defined(VIRTUAL_SHADOW) && !defined(VIRTUAL_SHADOW_MARK) && defined(GL_COMPUTE_SHADER)
+#if defined(VOLUMETRIC) && !defined(VIRTUAL_SHADOW) && defined(GL_COMPUTE_SHADER)
 layout(binding = 4) uniform sampler2D textureSm1;
 #endif
 
-#if defined(VOLUMETRIC) && defined(VIRTUAL_SHADOW_MARK) && defined(GL_COMPUTE_SHADER)
-layout(binding = 4, r32ui) uniform uimage3D pageTbl;
-layout(binding = 5, r32ui) uniform uimage3D pageTblDepth;
-#endif
-
 #if defined(VOLUMETRIC) && defined(VIRTUAL_SHADOW) && defined(GL_COMPUTE_SHADER)
 layout(binding = 4) uniform utexture3D pageTbl;
 layout(binding = 5) uniform texture2D  pageData;
@@ -59,60 +54,6 @@ const float dFogMax = 0.9999;
 uvec2 invocationID = gl_GlobalInvocationID.xy;
 #endif
 
-#if defined (VIRTUAL_SHADOW_MARK)
-shared uint pageHiZ[NumThreads];
-//uint pageHiZTh = 0xFFFFFFFF;
-
-void storeHiZValue(uint v) {
-  uvec4 dx = unpack565_16(v);
-  ivec3 at = ivec3(dx.xyz);
-  uint  iz = floatBitsToUint(dx.w/float(0xFFFF));
-  imageAtomicExchange(pageTbl, at, 1u);
-  imageAtomicMin(pageTblDepth, at, iz);
-  }
-
-void setupHiZ() {
-  const uint lane = gl_LocalInvocationIndex;
-  pageHiZ[lane] = 0xFFFFFFFF;
-  }
-
-void markPage(ivec3 at, float z) {
-  if(z<0 || z>=1)
-    return;
-
-  uint iz  = uint(z*0xFFFF);
-  uint cur = pack565_16(at,iz);
-  uint id  = pageIdHash7(at) % pageHiZ.length();
-
-  /*
-  if((pageHiZTh==0xFFFFFFFF) || (pageHiZTh&0xFFFF0000)==(cur&0xFFFF0000)) {
-    // thread local cache
-    pageHiZTh = min(pageHiZTh, cur);
-    return;
-    }
-  */
-
-  uint v   = atomicMin(pageHiZ[id], cur);
-  if(v==0xFFFFFFFF)
-    return; // clean insert
-  if((v&0xFFFF0000)==(cur&0xFFFF0000))
-    return; // update same entry
-
-  // imageAtomicAdd(pageTbl, ivec3(0), 1u); //counter
-  storeHiZValue(v);
-  }
-
-void flushHiZ() {
-  //if(pageHiZTh!=0xFFFFFFFF)
-  //  storeHiZValue(pageHiZTh);
-  const uint lane = gl_LocalInvocationIndex;
-  const uint v    = pageHiZ[lane];
-  if(v==0xFFFFFFFF)
-    return;
-  storeHiZValue(v);
-  }
-#endif
-
 float interleavedGradientNoise() {
 #if defined(GL_COMPUTE_SHADER)
   return interleavedGradientNoise(invocationID.xy);
@@ -121,25 +62,10 @@ float interleavedGradientNoise() {
 #endif
   }
 
-#if defined(VOLUMETRIC) && defined(VIRTUAL_SHADOW_MARK) && defined(GL_COMPUTE_SHADER)
-bool shadowFactor(vec4 shPos) {
-  vec3  shPos0 = shPos.xyz/shPos.w;
-
-  int   mip    = vsmCalcMipIndex(shPos0.xy, VSM_FOG_MIP);
-  vec2  page   = shPos0.xy / (1 << mip);
-  if(any(greaterThan(abs(page), vec2(1))))
-    return true;
-
-  ivec2 pageI = ivec2((page*0.5+0.5)*VSM_PAGE_TBL_SIZE);
-  ivec3 at    = ivec3(pageI, mip);
-  markPage(at, shPos0.z);
-  return true;
-  }
-#elif defined(VOLUMETRIC) && defined(VIRTUAL_SHADOW) && defined(GL_COMPUTE_SHADER)
+#if defined(VOLUMETRIC) && defined(VIRTUAL_SHADOW) && defined(GL_COMPUTE_SHADER)
 bool shadowFactor(vec4 shPos) {
   vec3  shPos0 = shPos.xyz/shPos.w;
-
-  int   mip    = vsmCalcMipIndex(shPos0.xy, VSM_FOG_MIP);
+  int   mip    = vsmCalcMipIndexFog(shPos0.xy);
   vec2  page   = shPos0.xy / (1 << mip);
   if(any(greaterThan(abs(page), vec2(1))))
     return true;
@@ -183,7 +109,7 @@ vec4 fog(vec2 uv, float z) {
   const vec3  pos1     = project(scene.viewProjectLwcInv, vec3(inPos,dFogMax));
   const vec3  posz     = project(scene.viewProjectLwcInv, vec3(inPos,z));
 
-#if defined(VIRTUAL_SHADOW) || defined(VIRTUAL_SHADOW_MARK)
+#if defined(VIRTUAL_SHADOW)
   const vec4  shPos0   = scene.viewVirtualShadowLwc*vec4(pos0, 1);
   const vec4  shPos1   = scene.viewVirtualShadowLwc*vec4(posz, 1);
 #else
@@ -312,15 +238,7 @@ void main_comp() {
 #endif
 
 void main() {
-#if defined(VIRTUAL_SHADOW_MARK) && defined(GL_COMPUTE_SHADER)
-  setupHiZ();
-  barrier();
-
-  main_comp();
-  barrier();
-
-  flushHiZ();
-#elif defined(GL_COMPUTE_SHADER)
+#if defined(GL_COMPUTE_SHADER)
   main_comp();
 #else
   main_frag();

shader/virtual_shadow/vsm_common.glsl

@@ -82,6 +82,12 @@ int vsmCalcMipIndex(in vec2 shPos, int minMip) {
   return max(vsmCalcMipIndex(shPos), minMip);
   }
 
+int vsmCalcMipIndexFog(in vec2 shPos) {
+  float d  = max(abs(shPos.x), abs(shPos.y));
+  uint  id = uint(d * 16.0);
+  return clamp(findMSB(id)+1, VSM_FOG_MIP, VSM_FOG_MIP+4);
+  }
+
 uint pageIdHash7(ivec3 src) {
   uint x = (src.x & 0x3) << 0;
   uint y = (src.y & 0x3) << 2;
@@ -97,6 +103,20 @@ float vsmTexelFetch(in texture2D pageData, const ivec2 pixel) {
   return texelFetch(pageData, pixel, 0).x;
   }
 
+uint shadowPageIdFetch(in vec2 page, in int mip, in utexture3D pageTbl) {
+  //page-local
+  const ivec2 pageI       = ivec2((page*0.5+0.5)*VSM_PAGE_TBL_SIZE);
+  const vec2  pageF       = fract((page*0.5+0.5)*VSM_PAGE_TBL_SIZE);
+  const ivec2 at          = ivec2(pageF*VSM_PAGE_SIZE);
+
+  //page-global
+  const uint  pageD       = texelFetch(pageTbl, ivec3(pageI, mip), 0).x;
+  if(pageD==0)
+    return -1;
+
+  return pageD >> 16u;
+  }
+
 float shadowTexelFetch(in vec2 page, in int mip, in utexture3D pageTbl,
                        #if defined(VSM_ATOMIC)
                        in utexture2D pageData
@@ -115,6 +135,8 @@ float shadowTexelFetch(in vec2 page, in int mip, in utexture3D pageTbl,
     return -1;
 
   const uint  pageId      = pageD >> 16u;
+
+  // const uint  pageId      = shadowPageIdFetch(page, mip, pageTbl);
   const ivec2 pageImageAt = unpackVsmPageId(pageId)*VSM_PAGE_SIZE + at;
   return vsmTexelFetch(pageData, pageImageAt);
   }

shader/virtual_shadow/vsm_direct_light.frag

@@ -42,6 +42,7 @@ layout(binding = 6) uniform utexture2D  pageData;
 #else
 layout(binding = 6) uniform texture2D   pageData;
 #endif
+layout(binding = 8, r32ui)  uniform readonly uimage2D dbg;
 
 
 layout(location = 0) out vec4 outColor;
@@ -109,7 +110,7 @@ int shadowLod(vec2 dx, vec2 dy) {
 
   const float bias = vsmMipBias;
   //return max(0, int((minLod + maxLod)*0.5 + bias + 0.5));
-  return max(0, int(minLod + bias + 0.5));
+  return max(0, int(minLod + bias));
   }
 
 float shadowTexelFetch(vec2 page, int mip) {
@@ -183,6 +184,12 @@ void main() {
 
   outColor = vec4(luminance * scene.exposure, 1);
 
+#if 0
+  const uint pageId = shadowPageIdFetch(page.xy,mip,pageTbl);
+  const uint v = imageLoad(dbg, unpackVsmPageId(pageId)).x;
+  outColor.rgb = vec3(v/512.0);
+#endif
+
 #if defined(DEBUG)
   const ivec2 pageI = ivec2((page.xy*0.5+0.5)*VSM_PAGE_TBL_SIZE);
   // int  mip   = 0;