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Dockers and toolbars
Freely dockable in main window or floatable (up to 16 separate dockers/toolbars)
Drag tabs from a docker to rearrange tabs, create a new docker in another location, or float windows
Create, customize, and freely dock or float toolbars for different uses
Envelope editing
Support for copying envelope points with the mouse
Groups of selected points act like contiguous items when moving or copying
Shift+control+drag on envelope segment (customizable) edits the envelope level within the time selection
Media Explorer preview time selection
Select a portion of a media file to insert into a project
Optionally loop and/or stretch the selected portion to fit the destination area and tempo
Scroll and zoom the media peaks preview
Control+alt drag the time selection to render a new cropped file to REAPER, the desktop, or a folder
Control+alt drag the time selection to sampler plugins or other applications that support drag/drop
Media Item Properties dialog
Item/Take Properties dialog stays open while you work elsewhere, follows changes in selected items
Pitch adjust and playrate fields accept values (such as "1.004") or simple operations (such as "x2")
MIDI editing
Set user-definable scales and chords in the MIDI editor for drawing and editing notes
Using mouse modifiers, copy/duplicate/paste actions can create pooled (ghosted) in-project MIDI source data
Editing any pooled MIDI media item affects all media items that share the same pooled data
Un-pool shared MIDI by gluing the media item or via MIDI source properties dialog
MIDI filter improvements when displaying multiple media items in the same editor
Many new mouse modifier behaviors to paint notes and chords, edit arpeggios, etc
Mouse modifier customization
Customize mouse behavior when using keyboard modifiers in 40 different contexts
In many contexts, mouse click and mouse drag can be customized separately
Assign different behaviors to the mouse when over the top or bottom half of a media item
Assign any action (including custom actions) to mouse click or double-click in most contexts
Existing/legacy mouse preferences are preserved, but user changes to mousemap settings will override
Actions to reassign default mouse action for any context
Lots of customizable choices of behavior, for example:
Move/copy just the selected area of media items, or all selected media items
Edit edges/fades for all selected items, or just those whose edges line up
Adjust media item volume or pitch
Move envelope points or MIDI notes/CC just horizontally or vertically
Assign marquee selection to left-click
Assign hand-drag-scroll to right-click
Many other customizable behaviors (50 behaviors just for media items)
Multichannel track monitoring/input recording/routing
Allow choosing greater than 2 channels of input (inputs must be sequential, though)
Multichannel track meters
Freely route any number of track channels to other tracks, hardware outputs
Project Bay
Manage, preview, search, replace project source media, media items, and FX
Manage media item groups and take comps for the project
Save/load project bay contents to create working sets of source media/FX for different purposes
Store sets of edited media items (including fades, stretch, pitch shift, etc) to use in any project
Media and FX+preset combinations can be stored, inserted, and switched in the project
ReaSurround: multi-channel surround panner with support for any number of input channels and speakers
Freely position input sources and speakers in 3D space
Configurable per-channel diffusion (treat input source audio as a shaped area rather than a point)
Drag track IO button to ReaSurround to add new input sources
Render and batch-convert improvements
Support for rendering project tracks and time regions to separate folders and files
Customizable wildcards provide great flexibility in naming batches of rendered/converted files
Save render presets for workflow efficiency
Take lanes and comping
Take lanes remain aligned by recording pass, creating empty lanes as needed (optional)
Each recording pass gets its own take lane, even when recording overlaps existing items
Recording no longer splits existing media items into different numbers of take lanes
Save/load named comps (sets of takes from multiple media items)
A/B or cycle through saved comps to audition/compare
Theme layout support (WALTER)
Per-track TCP/MCP layout support
Screensets support saving/restoring layouts
Old themes use default layouts available in Plugins/default_layouts.txt
New themes can define their own layouts
Layouts can be switched via menu, screensets/layouts dialog, or customizable actions
See:
http://www-dev.reaper.fm/sdk/walter/walter.php
Time selection
Default copy/cut actions respect time selection if there is one (including leading/trailing space)
Using mouse modifiers, copy/move behaviors can respect time selection if there is one
Editing behavior can be customized separately for media items, envelope points, MIDI editing
Track input FX chain support
FX in the input FX chain only run when record armed, and only affect the signal coming in
Input MIDI or audio, and set recording to be MIDI or audio independent of the input format
Improved pan support
Track stereo width controls and envelopes
Configurable track pan modes: balance, stereo pan (L/R + width), dual pan, and classic (3.x) balance
Transient detection and Dynamic Split improvements
Separate threshold and sensitivity settings and other options
Video
Many performance improvements, support for sequencing still images
Volume faders
New default hardware-emulation fader taper
4.0 sub-headline changes:
Always-on-top (pin) button for most windows, including FX windows
Automute safety feature is a global setting (rather than per-project), enabled by default
Crossfades: separate default settings for crossfade shapes, crossfade-on-split length
DDP export support (thanks to Sergej Marsnjak)
Envelopes: configurable transition time for automatically created edge points
Allows adjusting the ramp time when editing envelope segments
FX: combined REAPER presets and VST patches/AU presets in a single dropdown
FX: user can save a preset as default, to be automatically set when inserting the FX
FX browser: option to display/change default preset without opening the FX
FX sidechains are draggable
Drag track IO button to a plugin window to add destination track channels 3+4 and create a send
Installer (Windows): added "portable install" checkbox and more command line options
"Portable install" will install REAPER with no icons, registry keys, or uninstaller
User preferences and settings for portable installs are kept separate
Live FX multiprocessing now works more effectively when tracks are in folders
Media item fade drawing improvements, options to prevent editing fade-in/fade-out when the item is small
Media item selection sets can be named/saved/loaded using the screensets dialog
MIDI input/output: support for up to 62/64 separate input and output devices
Multichannel item improvements: allow choosing any mono/stereo pair from multichannel items
ReaVerb: huge realtime performance improvements
Sample rate conversion: improved sub-sample accuracy when used with project sample rate snap
Sample rate snap (enable in the snap settings dialog), improved sample-level display
Scale finder dialog: identify scales and chords based on input notes
Splash screen: displays when unloading projects (useful for status), other improvements
Time selection is editable in MIDI editor
Track Manager: basic report-style dialog to manage track visibility and selection
Track and send faders can be linked to MIDI volume/pan
Unlooped media item editing: dragging either edge of an item pads with silence
Video playback CPU/RAM/performance improvements and fixes
VoiceOver improvements for OSX (improves accessibility for visually impaired users)
WASAPI audio support (Windows), improvements to WDM/MME/DirectSound output modes
