Тройная буфферизация density volume

src/client/java/su/divan2000/veila/client/render/PostProcessingManager.java

@@ -48,6 +48,8 @@ public class PostProcessingManager {
     private static int rm_inverseProjectionLocation;
     private static int rm_depthSamplerLocation;
     private static int rm_fogVolumeLocation;
+    private static int rm_prevFogVolumeLocation;
+    private static int rm_fogInterpolationLocation;
     private static int rm_skyLightVolumeLocation;
     private static int rm_blockLightVolumeLocation;
     private static int rm_fogOriginLocation;
@@ -106,6 +108,8 @@ public class PostProcessingManager {
         rm_inverseProjectionLocation = raymarchProgram.uniform("InverseProjection");
         rm_depthSamplerLocation = raymarchProgram.uniform("DepthSampler");
         rm_fogVolumeLocation = raymarchProgram.uniform("FogVolume");
+        rm_prevFogVolumeLocation = raymarchProgram.uniform("PrevFogVolume");
+        rm_fogInterpolationLocation = raymarchProgram.uniform("FogInterpolation");
         rm_skyLightVolumeLocation = raymarchProgram.uniform("SkyLightVolume");
         rm_blockLightVolumeLocation = raymarchProgram.uniform("BlockLightVolume");
         rm_fogOriginLocation = raymarchProgram.uniform("FogOrigin");
@@ -280,14 +284,18 @@ public class PostProcessingManager {
         GL11.glBindTexture(GL12.GL_TEXTURE_3D, FogSimulationManager.getCurrentDensityTexture());
         GL20.glUniform1i(rm_fogVolumeLocation, 1);
 
-        // Light Volume
         GL13.glActiveTexture(GL13.GL_TEXTURE2);
-        GL11.glBindTexture(GL12.GL_TEXTURE_3D, FogLightVolume.getSkyLightTexture());
+        GL11.glBindTexture(GL12.GL_TEXTURE_3D, FogSimulationManager.getPreviousDensityTexture());
-        GL20.glUniform1i(rm_skyLightVolumeLocation, 2);
+        GL20.glUniform1i(rm_prevFogVolumeLocation, 2);
 
+        // Light Volume
         GL13.glActiveTexture(GL13.GL_TEXTURE3);
+        GL11.glBindTexture(GL12.GL_TEXTURE_3D, FogLightVolume.getSkyLightTexture());
+        GL20.glUniform1i(rm_skyLightVolumeLocation, 3);
+
+        GL13.glActiveTexture(GL13.GL_TEXTURE4);
         GL11.glBindTexture(GL12.GL_TEXTURE_3D, FogLightVolume.getBlockLightTexture());
-        GL20.glUniform1i(rm_blockLightVolumeLocation, 3);
+        GL20.glUniform1i(rm_blockLightVolumeLocation, 4);
 
         GL20.glUniform2i(rm_fogOriginLocation,
                 FogSystem.originChunkX() * FogWorldVolume.CHUNK_SIZE,
@@ -314,6 +322,7 @@ public class PostProcessingManager {
 
         // Цвет тумана
         GL20.glUniform3f(rm_fogColorLocation, fogR, fogG, fogB);
+        GL20.glUniform1f(rm_fogInterpolationLocation, FogSimulationManager.getFogInterpolationAlpha());
 
         // Яркость неба
         GL20.glUniform1f(rm_skyBrightnessLocation, client.world.getSkyBrightness(tickDelta));

src/client/java/su/divan2000/veila/client/render/fog/FogDensityTextures.java

@@ -14,7 +14,11 @@ public final class FogDensityTextures {
 
     private static int textureA = -1;
     private static int textureB = -1;
-    private static int readIndex = 0;
+    private static int textureC = -1;
+    private static int currentIndex = 0;
+    private static int previousIndex = 0;
+    private static int writeIndex = 1;
+    private static boolean hasPreviousState = false;
 
     // PBO для быстрой очистки регионов (half float нули)
     private static int clearPBO = -1;
@@ -54,6 +58,11 @@ public final class FogDensityTextures {
 
         textureA = createDensityTexture();
         textureB = createDensityTexture();
+        textureC = createDensityTexture();
+        currentIndex = 0;
+        previousIndex = 0;
+        writeIndex = 1;
+        hasPreviousState = false;
     }
 
     private static int createDensityTexture() {
@@ -87,15 +96,45 @@ public final class FogDensityTextures {
     }
 
     public static void swap() {
-        readIndex = 1 - readIndex;
+        previousIndex = currentIndex;
+        currentIndex = writeIndex;
+
+        // Выбираем свободный буфер для следующей записи
+        writeIndex = 0;
+        while (writeIndex == currentIndex || writeIndex == previousIndex) {
+            writeIndex++;
+        }
+
+        hasPreviousState = true;
     }
 
     public static int getReadTexture() {
-        return readIndex == 0 ? textureA : textureB;
+        return indexToTexture(currentIndex);
+    }
+
+    public static int getPreviousTexture() {
+        return indexToTexture(previousIndex);
     }
 
     public static int getWriteTexture() {
-        return readIndex == 0 ? textureB : textureA;
+        return indexToTexture(writeIndex);
+    }
+
+    public static boolean hasPreviousState() {
+        return hasPreviousState;
+    }
+
+    private static int indexToTexture(int index) {
+        switch (index) {
+            case 0:
+                return textureA;
+            case 1:
+                return textureB;
+            case 2:
+                return textureC;
+            default:
+                throw new IllegalStateException("Unexpected fog density texture index: " + index);
+        }
     }
 
     /**
@@ -108,6 +147,7 @@ public final class FogDensityTextures {
     ) {
         clearRegionsInTexture(textureA, physX, physZ, widthChunks, depthChunks, count);
         clearRegionsInTexture(textureB, physX, physZ, widthChunks, depthChunks, count);
+        clearRegionsInTexture(textureC, physX, physZ, widthChunks, depthChunks, count);
     }
 
     private static void clearRegionsInTexture(

src/client/java/su/divan2000/veila/client/render/fog/FogSimulationManager.java

@@ -7,8 +7,9 @@ public final class FogSimulationManager {
 
     private static boolean initialized = false;
     private static long lastSimulationTime = 0;
+    private static long lastSwapTimeNs = 0;
 
-    // Симулируем каждые 100 мс (10 раз в секунду)
+    // Симулируем каждые 300 мс (~3.3 раз в секунду)
     private static final long SIMULATION_INTERVAL_NS = 300_000_000L;
     private static final long TARGET_STEP_DURATION_NS = 300_000_000L;
     private static final long FRAME_TIME_WINDOW_NS = 100_000_000L;
@@ -119,6 +120,7 @@ public final class FogSimulationManager {
             long stepDuration = System.nanoTime() - simulationStartedAtNs;
             recordCompletedStep(stepDuration);
             FogDensityTextures.swap();
+            lastSwapTimeNs = System.nanoTime();
             simulationActive = false;
         }
     }
@@ -231,6 +233,25 @@ public final class FogSimulationManager {
         return FogDensityTextures.getReadTexture();
     }
 
+    public static int getPreviousDensityTexture() {
+        return FogDensityTextures.getPreviousTexture();
+    }
+
+    public static float getFogInterpolationAlpha() {
+        if (!FogDensityTextures.hasPreviousState()) {
+            return 1.0f;
+        }
+
+        long currentTime = System.nanoTime();
+        long elapsed = currentTime - lastSwapTimeNs;
+        if (elapsed <= 0) {
+            return 0.0f;
+        }
+
+        float alpha = (float) elapsed / (float) SIMULATION_INTERVAL_NS;
+        return Math.min(alpha, 1.0f);
+    }
+
     public static void setGlobalEmissionMultiplier(float value) {
         globalEmissionMultiplier = value;
     }

src/client/resources/assets/veila/shaders/fog_raymarching.frag

@@ -2,6 +2,7 @@
 
 uniform sampler2D DepthSampler;
 uniform sampler3D FogVolume;
+uniform sampler3D PrevFogVolume;
 uniform sampler3D SkyLightVolume;
 uniform sampler3D BlockLightVolume;
 
@@ -11,6 +12,7 @@ uniform mat4 InverseView;
 uniform vec3 FogColor;
 uniform vec3 CameraPosition;
 
+uniform float FogInterpolation;
 uniform float SkyBrightness;
 
 uniform ivec2 FogOrigin;
@@ -97,7 +99,9 @@ float density(vec3 worldPos)
 {
     vec3 uv = worldToUV(worldPos);
     if (uv.x < 0.0) return 0.0;
-    return texture(FogVolume, uv).r;
+    float currentDensity = texture(FogVolume, uv).r;
+    float prevDensity = texture(PrevFogVolume, uv).r;
+    return mix(prevDensity, currentDensity, FogInterpolation);
 }
 
 vec2 light(vec3 worldPos)