Add configurable vibe presets

src/config/vibe-presets.test.ts

@@ -0,0 +1,81 @@
+import { describe, expect, it } from 'vitest';
+
+import { runtimeControls } from './runtime-controls';
+import { vibePresets } from './vibe-presets';
+
+const FINAL_VIBE_NAMES = [
+  'Aurora Mycelium Copy',
+  'Velvet Observatory Copy',
+  'Lichen Signal',
+  'Tidepool Lantern',
+  'Paper Lantern Fog',
+  'Chrome Pollen',
+];
+
+const BLENDED_BRUSH_SIZE_MIN = 17;
+const BLENDED_CLARITY_MAX = 0.56;
+const SOFT_PARTICLE_BRUSH_SIZE_MAX = 5;
+const SOFT_PARTICLE_CLARITY_MAX = 0.2;
+
+// Performance guardrails — bumping any of these is an explicit perf trade-off.
+const MAX_SPAWN_PER_PIXEL = runtimeControls.spawnPerPixel?.max ?? 0.38;
+const MAX_BRUSH_SIZE = runtimeControls.brushSize?.max ?? 36;
+const HIGH_DENSITY_SPAWN_THRESHOLD = 0.28;
+const HIGH_DENSITY_DECAY_LIMIT = 940;
+const HIGH_DENSITY_BRUSH_SIZE_LIMIT = 14;
+const HIGH_DENSITY_TRAIL_WEIGHT_LIMIT = 0.055;
+
+describe('vibePresets', () => {
+  it('keeps the classic preset set distinct', () => {
+    expect(vibePresets.map((preset) => preset.name)).toEqual(FINAL_VIBE_NAMES);
+
+    const ids = vibePresets.map((preset) => preset.id);
+    expect(new Set(ids).size).toBe(vibePresets.length);
+  });
+
+  it('includes both blended and visibly particulate styles', () => {
+    const blendedNames = vibePresets
+      .filter(
+        (preset) =>
+          preset.settings.brushSize >= BLENDED_BRUSH_SIZE_MIN &&
+          preset.settings.clarity <= BLENDED_CLARITY_MAX
+      )
+      .map((preset) => preset.name);
+    const softParticleNames = vibePresets
+      .filter(
+        (preset) =>
+          preset.settings.brushSize <= SOFT_PARTICLE_BRUSH_SIZE_MAX &&
+          preset.settings.clarity <= SOFT_PARTICLE_CLARITY_MAX
+      )
+      .map((preset) => preset.name);
+
+    expect(blendedNames).toEqual(['Tidepool Lantern']);
+    expect(softParticleNames).toEqual(['Chrome Pollen']);
+  });
+
+  it('stays inside interactive performance guardrails', () => {
+    const violations = vibePresets.flatMap((preset) => {
+      const { name, settings } = preset;
+      const presetViolations: Array<string> = [];
+
+      if (settings.spawnPerPixel > MAX_SPAWN_PER_PIXEL) {
+        presetViolations.push(`${name} density exceeds ${MAX_SPAWN_PER_PIXEL}`);
+      }
+      if (settings.brushSize > MAX_BRUSH_SIZE) {
+        presetViolations.push(`${name} brush size exceeds ${MAX_BRUSH_SIZE}`);
+      }
+      if (
+        settings.spawnPerPixel >= HIGH_DENSITY_SPAWN_THRESHOLD &&
+        (settings.decayRateTrails > HIGH_DENSITY_DECAY_LIMIT ||
+          settings.brushSize > HIGH_DENSITY_BRUSH_SIZE_LIMIT ||
+          settings.individualTrailWeight > HIGH_DENSITY_TRAIL_WEIGHT_LIMIT)
+      ) {
+        presetViolations.push(`${name} combines high density with too much persistence`);
+      }
+
+      return presetViolations;
+    });
+
+    expect(violations).toEqual([]);
+  });
+});