Regions Guide
A region in Fracturing Fog is a saved view: center coordinates with full DD/QD limb fidelity, zoom factor, iteration count, fractal type, and optional preferred theme + bound saved-equation name.
Companion pages: User Index · Avalonia User Guide · Slideshow Guide
Think of regions as bookmarks for the fractal. You wander, you find a view you love, you press
V to bookmark it, and from that moment on it appears in the Region dropdown forever. Pick
it from any other session and you snap back to the exact same spot — same coordinates, same zoom,
same iteration count, same fractal family.
Two kinds of regions live in that dropdown:
| Kind | Where they live | Editable? |
|---|---|---|
| Built-in | Baked into the app — Classic Full View, Seahorse Valley, Elephant Valley, Mini Mandelbrot, Period-3 Bulb, etc. | no |
| Yours | Anything you save with V. Stored as plain JSON under %APPDATA%\FracturingFog\regions.json. |
yes |
Tip
Right-click the Region dropdown to sort: Default (built-ins first, then yours), or By Fractal Type (Mandelbrot bookmarks together, Julia bookmarks together, etc.). The setting persists per dropdown — toolbar and Floating Menu remember independently.
- Pan and zoom freely until you find a swirl that grabs you. Pay no attention to coordinates.
- Press
V. A name prompt opens, pre-filled with something sensible like "Mandelbrot zoom 1.4e12". - Change the name to anything you like — "the swirl above the spike" works.
- Hit OK.
Tomorrow:
- Launch the app. Open the Region dropdown.
- Pick your bookmark. The view snaps to the exact saved coordinates, with the same iteration count and fractal family.
- Open Floating Menu → Region Navigation → Exp… (Export).
- Pick a
.jsonfilename and save it. The file is text — a few KB. - Email / DM / Discord that file to your friend.
- They open Floating Menu → Region Navigation → Imp… (Import) and pick the file. Done — the region appears in their Region dropdown like any other.
Important
Regions remember the fractal type too. If you bookmark a Julia view, picking that bookmark snaps you straight into Julia — you do not need to switch the Type dropdown first.
When deep-zoom enthusiasts swap coordinates online, they paste pipe-separated limbs like:
-0.7548776661778 | 1.2e-17 | 0 | 0
Those four numbers are the high-precision representation of one axis. Fracturing Fog reads them natively:
- Open Floating Menu → Region Navigation.
- Click into the CX textbox and paste the line above. Repeat for CY with the imaginary half.
- Type your zoom into Zoom and your iteration count into Iter.
- Click Go. The view jumps.
Now press V to bookmark it so you do not have to paste again next time.
- Why Regions
- Built-in vs User Regions
- Save Workflow
- Apply Workflow
- Sort + Filter
- Export + Import
- JSON Schema
- Pipe-Separated Limb Format
- Slideshow Integration
- Tips
Manual pan + zoom + iter tuning to reach a memorable view takes minutes. Pasting the coordinates back later only works if you've recorded them at full precision — at zoom 10²⁵ a double-precision (x, y) is already inadequate.
Regions solve this by capturing every input the renderer needs, with extended-precision limbs preserved as-is, so re-applying a region is bit-exact.
| Category | Source | Editable? |
|---|---|---|
| Built-in | Baked into <install>\Resources\Regions\, ships with the EXE |
No |
| User | %APPDATA%\FracturingFog\regions.json |
Yes |
The built-in tour covers cardioid valley, period bulbs (2 / 3 / 4 / 5), seahorse valley, elephant valley, double-spirals, the antenna, multiple mini-Mandelbrots, and several deep-zoom showpieces (e.g., a 1e25 location demonstrating QD math).
Applying a built-in works; deleting one does not — the Delete button only acts on user entries.
- Pan / zoom / type-switch to the view you want.
- Press
V, or click Floating Menu → Region Navigation → Save. - The name prompt opens, pre-filled with a suggested name based on the active fractal + region area.
- Type a final name and confirm.
- If the name already exists in the user library, an overwrite confirmation prompt appears (added in v0.6.2). Confirm to replace, Cancel to back out.
- The new region appears in every region combo (toolbar + menu).
Auto-captured fields:
- Center coordinates (Hi + 3 low limbs per axis when DD/QD precision is engaged)
- Zoom
- Iterations (current or locked)
- Fractal type
- Theme name (if a non-default theme is active)
- Bound Sandbox / User Equation / User Bulb entry name (if applicable)
Selecting a region in any combo (toolbar OR menu):
- Pauses any in-flight calculation.
- Mutates the view state in place: pan/zoom anchored at the saved coordinate (full precision restored), iter count snapped to the saved value, fractal type re-selected if it differs.
- Re-applies the recorded theme if one is stored AND the corresponding Lock checkbox in Post-FX is OFF.
- Re-applies any bound saved equation (Sandbox / User Equation / User Bulb) by name. If the bound entry has been deleted, the engine falls back to the currently-loaded source — no error.
- Triggers a full-quality re-render.
The Slideshow engine uses the same Apply path under the hood — there is no separate ""slideshow region"" type.
Right-click any Region combo (toolbar OR menu) for the sort menu:
| Item | Effect |
|---|---|
| Default | Built-ins first, then user regions, original declared order |
| By Fractal Type → <type> | Filter to regions whose stored type matches <type> |
A non-selectable — select region — header is injected at the top of the filtered list — picking it has no effect (the VM filters em-dash-prefixed entries from selection handling).
Floating Menu → Region Navigation → Exp… opens a Save File dialog. The exported JSON contains your entire user region library (built-ins are not exported — they're already in the recipient's EXE).
Floating Menu → Region Navigation → Imp… opens an Open File dialog and merges the loaded regions into your library.
Name-collision handling (per-entry prompt):
| Action | Effect |
|---|---|
| Skip | Keep your existing entry; discard the import |
| Overwrite | Replace your entry with the imported version |
| Rename | Append a numeric suffix to the imported entry's name |
| Skip All / Overwrite All | Apply the choice to remaining collisions silently |
Each entry in regions.json is a single Region object:
{
"name": "Seahorse Valley Deep",
"type": "Mandelbrot",
"centerXHi": -0.7548409391432949,
"centerXLo1": 1.2e-17,
"centerXLo2": 0.0,
"centerXLo3": 0.0,
"centerYHi": 0.05716936067717272,
"centerYLo1": -3.4e-18,
"centerYLo2": 0.0,
"centerYLo3": 0.0,
"zoom": 1.2e15,
"iterations": 8192,
"quality": "Ultra",
"themeName": "Inferno Cycling",
"sandboxName": null,
"userEquationName": null,
"userBulbName": null,
"notes": "Deep dive into the central seahorse — see ridges around the spiral arm",
"isExtreme": false
}Field rules:
| Field | Required? | Notes |
|---|---|---|
name |
Yes | Must be unique within the file |
type |
Yes | Mirrors FractalType enum (case-sensitive) |
centerXHi / centerYHi
|
Yes | Standard double precision |
centerXLo1..3 / centerYLo1..3
|
No (default 0) | DD low limb + QD extra limbs |
zoom |
Yes | Double; scientific notation accepted |
iterations |
Yes | Integer ≥ 64 |
quality |
No | Suggested preset; falls back to current |
themeName |
No | Preferred theme |
sandboxName / userEquationName / userBulbName
|
No | Bound saved-equation reference |
notes |
No | Free-form |
isExtreme |
No | True = filtered out when Include extreme regions is off |
JSON is indented (System.Text.Json) — easy to diff and share. Field omission follows WhenWritingNull so null values disappear from the file entirely.
The CX / CY textboxes accept a special pipe-separated limb format for paste-back of high-precision coordinates without loss:
-0.7548409391432949 | 1.2e-17 | 0 | 0
| Limb | Position | Meaning |
|---|---|---|
| 1 | Hi | Standard double |
| 2 | Lo₁ | DD low word (~10⁻¹⁶ of Hi) |
| 3 | Lo₂ | QD second extra limb |
| 4 | Lo₃ | QD third extra limb |
Single-double paste-back drops the low limbs. Three- or four-limb paste-back round-trips DD / QD precision so a region saved at zoom 10²⁵ can be reproduced bit-exact across machines.
The Floating Menu's Copy button emits the limb format for CX and CY, plain values for Zoom and Iter.
Slideshow Settings exposes two region-affecting controls:
| Setting | Effect |
|---|---|
| Beats per Region | How many beats / seconds before the next region applies. Set to 0 to lock the active region. |
| Include extreme regions | When off, regions with isExtreme: true are skipped during slideshow rotation |
Shift+click the Slideshow button is a shortcut for ""lock the current region"" — equivalent to setting Beats per Region = 0 for the current session.
Use descriptive names. ""Seahorse Valley Deep"" beats ""DeepZoom27"" two weeks later.
Group with categories. The notes field is free-form — prefix with [Demo], [Showcase], [Bug] to filter by hand later.
Save before exploring. Pan + zoom doesn't undo. Save the current view as a region before chasing a new direction — if you lose the spot, the region is still in the library.
Edit JSON by hand. The file is plain JSON. Tweaking a stored zoom, iteration count, or theme name in your editor of choice and re-launching the shell picks up the change. Reload from the Floating Menu pulls the file without a restart.
Don't manually edit the limbs. The Lo₁/Lo₂/Lo₃ fields are arithmetic residuals. Editing one value without the others produces a non-normalized DD/QD number that may render as visual noise.
Pair regions with bound equations. If your view depends on a Sandbox or User Equation entry, save the region while that entry is active so the binding is captured. Sharing the region JSON + the equation JSON gives the recipient a one-click reproduction.
Use isExtreme for >10²⁰ zooms. Set this field by hand-editing JSON for regions you don't want appearing in casual slideshow rotation — the calmer rotation makes for a better demo.
Slideshow region filter applies to user regions too. A user region with isExtreme: true will be filtered just like a built-in extreme region. Useful for keeping your library tidy without removing the entry.
Regions Guide · Fracturing Fog · © 2026