Add minimap density heatmap by log level

- Analyzer collects per-bucket density during the existing scan pass
  (error/warning/info counts in 200 byte-position buckets)
- Minimap renders the density as a colored background layer:
  red=errors, amber=warnings, blue=info, intensity by frequency
- Zero performance cost: one extra increment per analyzed line, stored
  in compact Uint32Array; bucket count is fixed regardless of file size

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ozgesolidkey

src/main/analyzers/columnAwareAnalyzer.ts

@@ -62,6 +62,13 @@ export class ColumnAwareAnalyzer implements LogAnalyzer {
         error: 0, warning: 0, info: 0, debug: 0, trace: 0
       };
 
+      // Density buckets — 200 buckets keyed by byte position
+      // Used by the minimap to draw a heat map by log level
+      const DENSITY_BUCKETS = 200;
+      const densityError = new Uint32Array(DENSITY_BUCKETS);
+      const densityWarning = new Uint32Array(DENSITY_BUCKETS);
+      const densityInfo = new Uint32Array(DENSITY_BUCKETS);
+
       // Crash tracking
       const crashes: CrashEntry[] = [];
 
@@ -116,7 +123,14 @@ export class ColumnAwareAnalyzer implements LogAnalyzer {
         } else {
           level = this.detectLevelFromText(line) || undefined;
         }
-        if (level) levelCounts[level]++;
+        if (level) {
+          levelCounts[level]++;
+          // Update density bucket based on byte position
+          const bucket = Math.min(DENSITY_BUCKETS - 1, Math.floor((bytesRead / fileSize) * DENSITY_BUCKETS));
+          if (level === 'error') densityError[bucket]++;
+          else if (level === 'warning') densityWarning[bucket]++;
+          else if (level === 'info') densityInfo[bucket]++;
+        }
 
         // Extract message text
         let message = '';
@@ -239,7 +253,13 @@ export class ColumnAwareAnalyzer implements LogAnalyzer {
           : undefined,
         analyzerName: this.name,
         analyzedAt: Date.now(),
-        insights
+        insights,
+        density: {
+          buckets: DENSITY_BUCKETS,
+          error: Array.from(densityError),
+          warning: Array.from(densityWarning),
+          info: Array.from(densityInfo),
+        }
       };
 
     } catch (error) {

src/main/analyzers/types.ts

@@ -59,6 +59,13 @@ export interface AnalysisResult {
   analyzerName: string;
   analyzedAt: number;
   insights: AnalysisInsights;
+  // Density buckets for minimap heat map (indexed by file byte position)
+  density?: {
+    buckets: number;
+    error: number[];
+    warning: number[];
+    info: number[];
+  };
 }
 
 // Base interface - all analyzers must implement this

src/renderer/renderer.ts

@@ -3389,14 +3389,48 @@ function renderMinimapMarkers(): void {
   if (!minimapElement) return;
 
   // Remove existing markers
-  minimapElement.querySelectorAll('.minimap-bookmark, .minimap-search-marker, .minimap-notes-marker, .minimap-sc-marker, .minimap-annotation-marker').forEach(el => el.remove());
+  minimapElement.querySelectorAll('.minimap-bookmark, .minimap-search-marker, .minimap-notes-marker, .minimap-sc-marker, .minimap-annotation-marker, .minimap-density-bucket').forEach(el => el.remove());
 
   const totalLines = getTotalLines();
   if (totalLines === 0) return;
 
   const minimapHeight = minimapElement.clientHeight;
   const fragment = document.createDocumentFragment();
 
+  // Density heat map (background layer) — render first so markers appear on top
+  const density = (state.analysisResult as any)?.density;
+  if (density && density.buckets > 0) {
+    const buckets = density.buckets;
+    const bucketHeight = minimapHeight / buckets;
+    // Find max for normalization (to prevent over-saturation)
+    let maxVal = 1;
+    for (let i = 0; i < buckets; i++) {
+      const total = density.error[i] + density.warning[i] + density.info[i];
+      if (total > maxVal) maxVal = total;
+    }
+    for (let i = 0; i < buckets; i++) {
+      const errCount = density.error[i] || 0;
+      const warnCount = density.warning[i] || 0;
+      const infoCount = density.info[i] || 0;
+      const total = errCount + warnCount + infoCount;
+      if (total === 0) continue;
+      // Mix color based on dominant level
+      const intensity = Math.min(1, total / maxVal);
+      let color: string;
+      if (errCount > warnCount && errCount > infoCount) {
+        color = `rgba(255, 80, 80, ${intensity * 0.6})`;
+      } else if (warnCount > infoCount) {
+        color = `rgba(255, 180, 40, ${intensity * 0.5})`;
+      } else {
+        color = `rgba(100, 150, 255, ${intensity * 0.35})`;
+      }
+      const marker = document.createElement('div');
+      marker.className = 'minimap-density-bucket';
+      marker.style.cssText = `position:absolute;left:0;right:0;top:${i * bucketHeight}px;height:${Math.ceil(bucketHeight) + 1}px;background-color:${color};pointer-events:none;`;
+      fragment.appendChild(marker);
+    }
+  }
+
   // Add saved notes range markers (drawn first, behind other markers)
   for (const range of state.savedRanges) {
     const marker = document.createElement('div');