subframe tick interpollation fix

src/main/java/com/replaymod/render/capturer/RealLensOpenGlFrameCapturer.java

@@ -16,6 +16,9 @@ import com.replaymod.replay.ReplayModReplay;
 import com.replaymod.replaystudio.pathing.path.Timeline;
 import com.replaymod.simplepathing.SPTimeline;
 
+import com.replaymod.core.mixin.MinecraftAccessor;
+import com.replaymod.pathing.player.ReplayTimer;
+
 import org.apache.commons.lang3.tuple.Triple;
 
 import java.util.Collections;
@@ -111,6 +114,7 @@ public class RealLensOpenGlFrameCapturer
     private final Timeline timeline;
     private final ReplayHandler replayHandler;
     private final AccumulationBuffer accum = new AccumulationBuffer();
+    private long lastConsumedTime = -1;
 
     public RealLensOpenGlFrameCapturer(
             WorldRenderer worldRenderer,
@@ -160,6 +164,16 @@ public class RealLensOpenGlFrameCapturer
                 tSub = (long) (frameId * dt);
             }
             long replayTime = replayHandler.getReplaySender().currentTimeStamp();
+            if (lastConsumedTime < 0) lastConsumedTime = replayTime;
+            int pendingTicks = (int) (replayTime / 50L - lastConsumedTime / 50L);
+            if (pendingTicks > 0) {
+                ReplayTimer timer = (ReplayTimer) ((MinecraftAccessor) mc).getTimer();
+                while (pendingTicks-- > 0) {
+                    mc.tick();              // двигает prev/cur частиц через границу тика
+                    timer.tickDelta -= 1f;  // компенсация: VideoRenderer не должен тикнуть повторно
+                }
+            }
+            if (replayTime > lastConsumedTime) lastConsumedTime = replayTime;
             float subPartialTicks = (float) ((replayTime % 50L) / 50.0);
 
             float focal = positionPath.getValue(LensProperties.FOCAL_DISTANCE,  tSub).map(Triple::getLeft).orElse(5.0f);

src/main/java/com/replaymod/render/utils/AccumulationBuffer.java

@@ -11,6 +11,7 @@ import org.joml.Matrix4f;
 import org.lwjgl.opengl.GL11;
 import org.lwjgl.opengl.GL12;
 import org.lwjgl.opengl.GL30;
+import org.lwjgl.opengl.GL33;
 
 import java.nio.ByteBuffer;
 import java.nio.FloatBuffer;
@@ -77,6 +78,11 @@ public class AccumulationBuffer {
         RenderSystem.setShader(GameRenderer::getPositionTexProgram);
         RenderSystem.setShaderTexture(0, srcColorTex);
 
+        int prevTex = GL11.glGetInteger(GL11.GL_TEXTURE_BINDING_2D);
+        GL11.glBindTexture(GL11.GL_TEXTURE_2D, srcColorTex);
+        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL33.GL_TEXTURE_SWIZZLE_A, GL11.GL_ONE);
+        GL11.glBindTexture(GL11.GL_TEXTURE_2D, prevTex);
+
         Tessellator tessellator = Tessellator.getInstance();
         BufferBuilder bb = tessellator.getBuffer();
         bb.begin(GL11.GL_QUADS, VertexFormats.POSITION_TEXTURE);
@@ -86,12 +92,19 @@ public class AccumulationBuffer {
         bb.vertex(-1f,  1f, 0f).texture(0f, 1f).next();
         tessellator.draw();
 
+        prevTex = GL11.glGetInteger(GL11.GL_TEXTURE_BINDING_2D);
+        GL11.glBindTexture(GL11.GL_TEXTURE_2D, srcColorTex);
+        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL33.GL_TEXTURE_SWIZZLE_A, GL11.GL_ALPHA);
+        GL11.glBindTexture(GL11.GL_TEXTURE_2D, prevTex);
+
         RenderSystem.getModelViewStack().pop();
         RenderSystem.applyModelViewMatrix();
         RenderSystem.setProjectionMatrix(savedProj, savedSorter);
         RenderSystem.disableBlend();
         RenderSystem.depthMask(true);
         RenderSystem.enableDepthTest();
+
+        RenderSystem.defaultBlendFunc();
     }
 
     public ByteBuffer finishAveraged(int samples) {