This document summarizes changes between v1.6 and the current v1.7 release line.
Versioning
Release target: v2.0
Previous documented release line: v1.7
Source: /Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/Mandelbrot Metal.xcodeproj/project.pbxproj
User-Facing Changes
Fractal mode selector added
Mandelbrot Metal now includes a compact toolbar selector for choosing the fractal family. The default remains Mandelbrot Set, and Julia Set is now available as a second mode.
The HUD title follows the active mode, so captures and exploration sessions identify whether the current view is Mandelbrot or Julia.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/ContentViewSupportTypes.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/FractalVM.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/ContentView.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/MandelbrotRenderer.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Mandelbrot.metal
Bookmarks preserve and sort by mode
Bookmarks now save the active fractal mode and restore it when opened. Manage Bookmarks also includes Mode as a sort option, and name-sorted rows show the saved mode so mixed Mandelbrot/Julia collections remain easy to scan.
Sharing metadata was updated so exported bookmarks can carry the saved fractal mode while remaining backward-compatible with older bookmark data.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Bookmark.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/ContentViewBookmarks.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/ContentViewImport.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/ContentViewSharing.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/ContentViewModels.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/UI/ContentViewManagementViews.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Sharing/SharingModels.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Sharing/SharingValidation.swift
Ultra-wide palette library expanded
The v2.0 line expands Mandelbrot Metal’s curated ultra-wide palette collection. The palette catalog now includes an additional ultra-wide catalog file and updates across the existing ultra-wide sets.
Net effect: users have a broader range of long-form color ramps for deep zooms, high-iteration renders, and exported artwork, with more visual variety before needing to import a custom palette.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Palettes/PaletteCatalog+UltraWide 1.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Palettes/PaletteCatalog+UltraWide 2.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Palettes/PaletteCatalog+UltraWide 3.swift
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Palettes/PaletteCatalog+UltraWide 4.swift
Palette metadata refined
Palette option metadata was updated alongside the expanded catalog. This supports cleaner palette presentation and better organization for the enlarged palette set.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Palettes/PaletteOption.swift
Onboarding refreshed for the new release
The welcome/onboarding flow was updated so new and returning users can see the latest improvements in the app experience.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Help/WelcomeOnboardingView.swift
Review prompt timing adjusted
The review prompt manager was updated for this release line. The intent is to keep review prompting tied to meaningful app use while avoiding interruptions during active exploration and rendering.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/ReviewPromptManager.swift
Rendering/Performance Tuning
Shader hot path trimmed without reducing quality
Several small GPU-side optimizations were made in the Mandelbrot kernel:
Repeated smooth escape/color-shaping logic was consolidated into helper functions.
The expensive contrast pow() step is skipped when contrast is neutral.
Unused per-sample lighting accumulator work was removed.
Redundant safe-write checks were removed after the kernel’s existing bounds guard.
Net effect: each rendered pixel does slightly less work while preserving the same visual quality and iteration behavior.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/Mandelbrot.metal
Progressive deep-render redraws coalesced
The CPU deep-render path now coalesces progressive tile redraw requests. Instead of asking the main run loop to redraw for every completed tile, tile completion wakes are grouped so the renderer schedules fewer redundant display updates.
Net effect: deep CPU refinement remains progressive, but the app spends less time scheduling duplicate redraws while tiles complete.
Source changes:
/Users/michaeldstebel/Library/CloudStorage/Dropbox/Xcode/MandelbrotMetal New/MandelbrotMetal/MandelbrotRenderer.swift
Build Verification
Debug simulator build succeeded.
Release simulator build succeeded.
Release build included Metal compilation and the full optimized Swift build.
Notes
The bulk of v2.0 is focused on fractal mode selection, bookmark mode preservation, render-path performance improvements, and palette expansion.
Julia rendering currently uses the GPU path with the shared color, palette, SSAA, lighting, capture, and bookmark controls. The Mandelbrot-specific deep CPU and perturbation paths remain focused on Mandelbrot Set exploration.
The rendering changes are intended to be quality-preserving: they remove redundant work rather than lowering samples, iterations, precision, or palette fidelity.
This document summarizes changes between v1.6 and the current v1.7 release line.
Versioning
Release target: v1.7
Previous documented release line: v1.6
Rendering/Performance Tuning
Shader hot path trimmed without reducing quality
Several small GPU-side optimizations were made in the Mandelbrot kernel:
Net effect: each rendered pixel does slightly less work while preserving the same visual quality and iteration behavior.
Progressive deep-render redraws coalesced
The CPU deep-render path now coalesces progressive tile redraw requests. Instead of asking the main run loop to redraw for every completed tile, tile completion wakes are grouped so the renderer schedules fewer redundant display updates.
Net effect: deep CPU refinement remains progressive, but the app spends less time scheduling duplicate redraws while tiles complete.
User-Facing Changes
Ultra-wide palette library expanded
The v1.7 line expands Mandelbrot Metal's curated ultra-wide palette collection. The palette catalog now includes an additional ultra-wide catalog file and updates across the existing ultra-wide sets.
Net effect: users have a broader range of long-form color ramps for deep zooms, high-iteration renders, and exported artwork, with more visual variety before needing to import a custom palette.
Palette metadata refined
Palette option metadata was updated alongside the expanded catalog. This supports cleaner palette presentation and better organization for the enlarged palette set.
Onboarding refreshed for the new release
The welcome/onboarding flow was updated so new and returning users can see the latest improvements in the app experience.
Review prompt timing adjusted
The review prompt manager was updated for this release line. The intent is to keep review prompting tied to meaningful app use while avoiding interruptions during active exploration and rendering.
Build Verification
Debug simulator build succeeded.
Release simulator build succeeded.
Release build included Metal compilation and the full optimized Swift build.
Notes
The bulk of v1.7 is focused on palette expansion, release-facing onboarding updates, review prompt refinement, and incremental render-path performance improvements.
No major fractal algorithm rewrite was introduced in this release line.
The rendering changes are intended to be quality-preserving: they remove redundant work rather than lowering samples, iterations, precision, or palette fidelity.
This document summarizes the changes between v1.5 and v1.6.
Versioning
MARKETING_VERSION: 1.5.2 -> 1.6
CURRENT_PROJECT_VERSION: 458 -> 462
User-Facing Changes
Bookmark manager sorting expanded
The Manage Bookmarks sheet now supports additional sort modes:
Newest
Name
Palette (new)
Iterations (new)
Scale (new)
Bookmark row metadata adapts to the selected sort
Bookmark rows now display context-specific secondary text in the list:
When sorting by Palette: shows the bookmark palette label
When sorting by Iterations: shows the saved iteration count
When sorting by Scale: shows the saved scale in scientific form
Help and onboarding updates for bookmark sorting
Help content now documents bookmark sorting options and behavior.
The "What’s New" onboarding content now highlights improved bookmark management.
Rendering/Performance Tuning
CPU deep-render handoff threshold adjusted
Deep CPU mode activation threshold was raised:
cpuDeepZoomThresholdSPU: 5.0e7 -> 8.0e7
CPU-mode hysteresis was tightened:
enter: 1.0 -> 1.10
exit: 0.7 -> 0.98
Net effect: the renderer stays on the GPU path longer before switching to CPU deep rendering.
Notes
The bulk of v1.6 focuses on the bookmark management UX and documentation.
No major fractal algorithm rewrite was introduced in the v1.5 -> v1.6a commit range.
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