feat: clumping echoes in nuggets

Now we have:

- limited number of `Echo`s -- they should be ideally only one per Id,
  for now it is one per one scan; in the future, the label might be also
  stored there
- `BlockEcho` is an `Echo` with a position and ping time.
- _(new)_ `EchoState` is a `BlockEcho`, with information, which sides
  and edges are visible
- _(new)_ `EchoNugget` is a clump of all touching echoes of the same id
- `BlockEchoes` is a container for all known `BlockEcho`es and now a
  container of all known `EchoNugget`s

fixes: #22
closes: #23

docs/roadmap.md

@@ -6,20 +6,24 @@
 - [x] `NullPointerException` when a scanner is active and world disappears (bug: #21, pr: #25)
 - [ ] clumps of blocks (bug for internal walls: #22, issue: #23, pr: ?)
   - [ ] bounds for frustum
-  - [ ] walls no longer flicker
-  - [ ] focused clump has an outline (at minimum, `DEBUG_LINES`) — so we have external vertices for camera distance calculation
+  - [x] walls no longer flicker
+  - [x] focused clump has an outline (at minimum, `DEBUG_LINES`) — ...
+  - [ ] ... so we have external vertices for camera distance calculation
 
 ## Bugs
 
-- [ ] Settings
-  - [ ] only one setting at a time is saved
+- [x] Settings
+  - [x] only one setting at a time is saved
 
-- [ ] Scanner
-  - [ ] internal walls tend to flicker in and out of existence
-  - [ ] closing app / disconnecting from server ends with a `NullPointerException` if the scanner is active
+- [x] Scanner
+  - [x] internal walls tend to flicker in and out of existence
+  - [x] closing app / disconnecting from server ends with a `NullPointerException` if the scanner is active
 
 ## Features
 
+- [ ] Settings
+  - [ ] per-world saves on top of common defaults
+    - [ ] _end of minimal viable code_
 - [ ] Scanner
   - [ ] clumps of blocks
   - [ ] label the clumps

fabric/any/src/main/java/com/midnightbits/scanner/fabric/FabricAnimationHost.java

@@ -28,7 +28,8 @@ public void initialize(Sonar source) {
                 return;
 
             this.tick(Clock.currentTimeMillis());
-            this.source.remove(this.source.oldEchoes(new MinecraftClientCore(client)));
+            if (this.source.remove(this.source.oldEchoes(new MinecraftClientCore(client))))
+                this.source.splitToNuggets();
         });
         WorldRenderEvents.LAST.register(this::renderLevel);
     }
@@ -45,6 +46,6 @@ public void apply(List<Shimmers> shimmers) {
     private void renderLevel(WorldRenderContext context) {
         final var shimmers = new GatherShimmers();
         this.run(shimmers);
-        Pixel.renderLevel(context, source.echoes(), shimmers.cloud);
+        Pixels.renderLevel(context, source.nuggets(), shimmers.cloud);
     }
 }

fabric/any/src/main/java/com/midnightbits/scanner/fabric/Pixels.java

@@ -0,0 +1,103 @@
+// Copyright (c) 2024 Marcin Zdun
+// This code is licensed under MIT license (see LICENSE for details)
+
+package com.midnightbits.scanner.fabric;
+
+import java.util.List;
+
+import com.midnightbits.scanner.sonar.EchoNugget;
+import com.midnightbits.scanner.sonar.graphics.*;
+import net.minecraft.client.render.*;
+import net.minecraft.util.math.Box;
+import org.joml.Matrix4f;
+
+import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.systems.RenderSystem;
+
+import net.fabricmc.fabric.api.client.rendering.v1.WorldRenderContext;
+
+public class Pixels {
+
+    private record GlProgramVertexConsumer(VertexConsumer buffer) implements GlProgramConsumer {
+        @Override
+        public void vertexColor(Matrix4f matrix, float x, float y, float z, int argb32) {
+            buffer.vertex(matrix, x, y, z).color(argb32);
+        }
+    }
+
+    public static void renderLevel(WorldRenderContext context, List<EchoNugget> nuggets, List<Shimmers> shimmers) {
+        final var frustum = context.frustum();
+        if (frustum == null) {
+            return;
+        }
+
+        final var contextMatrices = context.matrixStack();
+        if (contextMatrices == null) {
+            return;
+        }
+
+        final var matrices = new MatrixStack(contextMatrices.peek().getPositionMatrix());
+
+        final var camera = context.camera();
+        final var cameraPos = camera.getPos().toVector3f();
+
+        final var frustumFilter = new FrustumFilter() {
+            @Override
+            public boolean contains(EchoState.AABB bounds) {
+                return frustum.isVisible(
+                        new Box(bounds.minX(), bounds.minY(), bounds.minZ(),
+                                bounds.maxX(), bounds.maxY(), bounds.maxZ()));
+            }
+        };
+
+        final var allShimmers = EchoNugget.group(Shimmers.toEchoStates(shimmers, .5));
+
+        final var visibleNuggets = EchoNugget.filterVisible(nuggets, frustumFilter);
+        final var visibleShimmers = EchoNugget.filterVisible(allShimmers, frustumFilter);
+
+        if (visibleNuggets.isEmpty() && visibleShimmers.isEmpty()) {
+            return;
+        }
+
+        RenderSystem.disableDepthTest();
+        RenderSystem.enableBlend();
+        RenderSystem.blendFunc(
+                GlStateManager.SrcFactor.SRC_ALPHA,
+                GlStateManager.DstFactor.ONE_MINUS_SRC_ALPHA);
+        RenderSystem.setShader(GameRenderer::getPositionColorProgram);
+        RenderSystem.setShaderColor(1.0F, 1.0F, 1.0F, 1.0F);
+
+        final var tessellator = Tessellator.getInstance();
+        {
+            final var buffer = tessellator.begin(VertexFormat.DrawMode.TRIANGLES, VertexFormats.POSITION_COLOR);
+            final var glProgram = new GlProgramVertexConsumer(buffer);
+
+            for (final var nugget : visibleShimmers) {
+                 nugget.draw(glProgram, matrices, cameraPos);
+            }
+
+            for (final var nugget: visibleNuggets) {
+                nugget.draw(glProgram, matrices, cameraPos);
+            }
+
+            final var builtBuffer = buffer.endNullable();
+            if (builtBuffer != null)
+                BufferRenderer.drawWithGlobalProgram(builtBuffer);
+        }
+
+        {
+            final var buffer = tessellator.begin(VertexFormat.DrawMode.DEBUG_LINES, VertexFormats.POSITION_COLOR);
+            final var glProgram = new GlProgramVertexConsumer(buffer);
+
+            for (final var nugget: visibleNuggets) {
+                nugget.sketch(glProgram, matrices, cameraPos);
+            }
+
+            final var builtBuffer = buffer.endNullable();
+            if (builtBuffer != null)
+                BufferRenderer.drawWithGlobalProgram(builtBuffer);
+        }
+
+        RenderSystem.enableDepthTest();
+    }
+}