TODO.txt - external/github.com/ocornut/imgui - Git at Google

 dear imgui
 ISSUES & TODO LIST

 Issue numbers (#) refer to github issues listed at https://github.com/ocornut/imgui/issues/XXXX
 The list below consist mostly of ideas noted down before they are requested/discussed by users (at which point they usually exist on the github issue tracker).
 It's mostly a bunch of personal notes, probably incomplete. Feel free to query if you have any questions.

  - doc/test: add a proper documentation+regression testing system (#435)
  - doc/test: checklist app to verify binding/integration of imgui (test inputs, rendering, callback, etc.).
  - project: folder or separate repository with maintained helpers (e.g. imgui_memory_editor.h, imgui_stl.h, maybe imgui_dock would be there?)

  - window: calling SetNextWindowSize() every frame with <= 0 doesn't do anything, may be useful to allow (particularly when used for a single axis). (#690)
  - window: add a way for very transient windows (non-saved, temporary overlay over hundreds of objects) to "clean" up from the global window list. perhaps a lightweight explicit cleanup pass.
  - window: auto-fit feedback loop when user relies on any dynamic layout (window width multiplier, column) appears weird to end-user. clarify.
  - window: allow resizing of child windows (possibly given min/max for each axis?.)
  - window: background options for child windows, border option (disable rounding).
  - window: resizing from any sides? + mouse cursor directives for app. (#822)
 !- window: begin with *p_open == false should return false.
  - window: get size/pos helpers given names (see discussion in #249)
  - window: a collapsed window can be stuck behind the main menu bar?
  - window: when window is very small, prioritize resize button over close button.
  - window: detect extra End() call that pop the "Debug" window out and assert at End() call site instead of at end of frame.
  - window/tooltip: allow to set the width of a tooltip to allow TextWrapped() etc. while keeping the height automatic.
  - window: increase minimum size of a window with menus or fix the menu rendering so that it doesn't look odd.
  - window: double-clicking on title bar to minimize isn't consistent, perhaps move to single-click on left-most collapse icon?
  - window: expose contents size. (#1045)
  - window: GetWindowSize() returns (0,0) when not calculated? (#1045)
 !- scrolling: allow immediately effective change of scroll after Begin() if we haven't appended items yet.
  - scrolling/clipping: separator on the initial position of a window is not visible (cursorpos.y <= clippos.y). (2017-08-20: can't repro)

  - drawlist: move Font, FontSize, FontTexUvWhitePixel inside ImDrawList and make it self-contained (apart from drawing settings?)
  - drawlist: make it easier to toggle AA per primitive, so we can use e.g. non-AA fill + AA borders more naturally
  - drawlist: end-user probably can't call Clear() directly because we expect a texture to be pushed in the stack.
  - drawlist: maintaining bounding box per command would allow to merge draw command when clipping isn't relied on (typical non-scrolling window or non-overflowing column would merge with previous command).
  - drawlist: avoid passing null (-9999,+9999) rectangle to end-user, instead perhaps pass rectangle based on io.DisplaySize?
  - drawlist: primtiives/helpers to manipulate vertices post submission, so e.g. a quad/rect can be resized to fit later submitted content, _without_ using the ChannelSplit api

  - main: considering adding an Init() function? some constructs are awkward in the implementation because of the lack of them.
  - main: find a way to preserve relative orders of multiple reappearing windows (so an app toggling between "modes" e.g. fullscreen vs all tools) won't lose relative ordering.
  - main: IsItemHovered() make it more consistent for various type of widgets, widgets with multiple components, etc. also effectively IsHovered() region sometimes differs from hot region, e.g tree nodes
  - main: IsItemHovered() info stored in a stack? so that 'if TreeNode() { Text; TreePop; } if IsHovered' return the hover state of the TreeNode?
  - main: rename the main "Debug" window to avoid ID collision with user who may want to use "Debug" with specific flags.

  - widgets: display mode: widget-label, label-widget (aligned on column or using fixed size), label-newline-tab-widget etc. (#395)
  - widgets: clean up widgets internal toward exposing everything and stabilizing imgui_internals.h.
  - widgets: add disabled and read-only modes (#211)
  - widgets: alignment options in style (e.g. center Selectable, Right-Align within Button, etc.) #1260
  - widgets: activate by identifier (trigger button, focus given id)

  - input text: clean up the mess caused by converting UTF-8 <> wchar. the code is rather inefficient right now and super fragile.
  - input text: reorganize event handling, allow CharFilter to modify buffers, allow multiple events? (#541)
  - input text: expose CursorPos in char filter event (#816)
  - input text: access public fields via a non-callback API e.g. InputTextGetState("xxx") that may return NULL if not active.
  - input text: flag to disable live update of the user buffer (also applies to float/int text input) (#701)
  - input text: way to dynamically grow the buffer without forcing the user to initially allocate for worse case, e.g. more natural std::string (follow up on #200)
  - input text: hover tooltip could show unclamped text
  - input text: add ImGuiInputTextFlags_EnterToApply? (off #218)
  - input text: easier ways to update buffer (from source char*) while owned. preserve some sort of cursor position for multi-line text.
  - input text: add discard flag (e.g. ImGuiInputTextFlags_DiscardActiveBuffer) or make it easier to clear active focus for text replacement during edition (#725)
  - input text: display bug when clicking a drag/slider after an input text in a different window has all-selected text (order dependant). actually a very old bug but no one appears to have noticed it.
  - input text multi-line: don't directly call AddText() which does an unnecessary vertex reserve for character count prior to clipping. and/or more line-based clipping to AddText(). and/or reorganize TextUnformatted/RenderText for more efficiency for large text (e.g TextUnformatted could clip and log separately, etc).
  - input text multi-line: line numbers? status bar? (follow up on #200)
  - input text multi-line: behave better when user changes input buffer while editing is active (even though it is illegal behavior). namely, the change of buffer can create a scrollbar glitch (#725)
  - input text multi-line: better horizontal scrolling support (#383, #1224)
  - input text: allow centering/positioning text so that ctrl+clicking Drag or Slider keeps the textual value at the same pixel position.
  - input number: optional range min/max for Input*() functions
  - input number: holding [-]/[+] buttons could increase the step speed non-linearly (or user-controlled)
  - input number: use mouse wheel to step up/down
  - input number: applying arithmetics ops (+,-,*,/) messes up with text edit undo stack.

  - layout: helper or a way to express ImGui::SameLine(ImGui::GetCursorStartPos().x + ImGui::CalcItemWidth() + ImGui::GetStyle().ItemInnerSpacing.x); in a simpler manner.
  - layout: generalization of the above: a concept equivalent to word processor ruler tab stop ~ mini columns (position in X, no clipping implied) (vaguely relate to #267, #395, also what is used internally for menu items)
  - layout: horizontal layout helper (#97)
  - layout: horizontal flow until no space left (#404)
  - layout: more generic alignment state (left/right/centered) for single items?
  - layout: clean up the InputFloatN/SliderFloatN/ColorEdit4 layout code. item width should include frame padding.
  - layout: BeginGroup() needs a border option.
  - layout: vertical alignement of mixed height items (e.g. buttons) within a same line (#1284)

  - columns: sizing policy (e.g. for each column: fixed size, %, fill, distribute default size among fills) (#513, #125)
  - columns: add a conditional parameter to SetColumnOffset() (#513, #125)
  - columns: headers. with sort op/button. reorderable. (#513, #125)
  - columns: allow columns to recurse.
  - columns: separator function or parameter that works within the column (currently Separator() bypass all columns) (#125)
  - columns: flag to add horizontal separator above/below?
  - columns/layout: setup minimum line height (equivalent of automatically calling AlignFirstTextHeightToWidgets)

 !- color: the color conversion helpers/types are a mess and needs sorting out.
  - color: (api breaking) ImGui::ColorConvertXXX functions should be loose ImColorConvertXX to match imgui_internals.h
  - coloredit: it is still somehow awkward to copy colors around (unless going through Hex mode).

  - plot: full featured plot/graph api w/ scrolling, zooming etc. all bell & whistle. why not!
  - plot: PlotLines() should use the polygon-stroke facilities, less verticles (currently issues with averaging normals)
  - plot: make it easier for user to draw extra stuff into the graph (e.g: draw basis, highlight certain points, 2d plots, multiple plots)
  - plot: "smooth" automatic scale over time, user give an input 0.0(full user scale) 1.0(full derived from value)
  - plot: option/feature: draw the zero line
  - plot: option/feature: draw grid, vertical markers
  - plot: option/feature: draw unit
  - plot: add a helper e.g. Plot(char* label, float value, float time_span=2.0f) that stores values and Plot them for you - probably another function name. and/or automatically allow to plot ANY displayed value (more reliance on stable ID)

  - clipper: ability to force display 1 item in the list would be convenient.

  - splitter/separator: formalize the splitter idiom into an official api (we want to handle n-way split) (#319)

  - dock: docking extension
  - dock: dock out from a collapsing header? would work nicely but need emitting window to keep submitting the code.

  - tabs: re-ordering, close buttons, context menu, persistent order (#261, #351)

  - ext: stl-ish friendly extension (imgui_stl.h) that has wrapped for std::string, std::vector etc.

  - button: provide a button that looks framed.
  - image/image button: misalignment on padded/bordered button?
  - image/image button: parameters are confusing, image() has tint_col,border_col whereas imagebutton() has bg_col/tint_col. Even thou they are different parameters ordering could be more consistent. can we fix that?
  - image button: not taking an explicit id is odd.
  - slider: allow using the [-]/[+] buttons used by InputFloat()/InputInt()
  - slider: initial absolute click is imprecise. change to relative movement slider (same as scrollbar).
  - slider: add dragging-based widgets to edit values with mouse (on 2 axises), saving screen real-estate.
  - slider: tint background based on value (e.g. v_min -> v_max, or use 0.0f either side of the sign)
  - slider: precision dragging
  - slider: step option (#1183)
  - knob: rotating knob widget (#942)
  - slider & drag: int data passing through a float
  - drag float: up/down axis
  - drag float: added leeway on edge (e.g. a few invisible steps past the clamp limits)

  - combo: sparse combo boxes (via function call?) / iterators
  - combo: active item type could be anything else e.g. void*
  - combo: use clipper
  - combo: contents should extends to fit label if combo widget is small
  - combo: option for ComboEx to not return true when unchanged (#1182)
  - combo/listbox: keyboard control. need InputText-like non-active focus + key handling. considering keyboard for custom listbox (pr #203)
  - listbox: multiple selection.
  - listbox: unselect (#1208)
  - listbox: make it easier/more natural to implement range-select (need some sort of info/ref about the last clicked/focused item that user can translate to an index?)
  - listbox: user may want to initial scroll to focus on the one selected value?
  - listbox: expose hovered item for a basic ListBox
  - listbox: keyboard navigation.
  - listbox: scrolling should track modified selection.

 !- popups/menus: clarify usage of popups id, how MenuItem/Selectable closing parent popups affects the ID, etc. this is quite fishy needs improvement! (#331, #402)
  - popups/nav: esc/enter default behavior for popups.
  - popups: reopening context menu at new position should be the behavior by default? (equivalent to internal OpenPopupEx() with reopen_existing=true)
  - popups: if the popup functions took explicit ImGuiID it would allow the user to manage the scope of those ID. (#331)
  - popups: clicking outside (to close popup) and holding shouldn't drag window below.
  - popups: add variant using global identifier similar to Begin/End (#402)
  - popups: border options. richer api like BeginChild() perhaps? (#197)
  - tooltip: tooltip that doesn't fit in entire screen seems to lose their "last preferred direction" and may teleport when moving mouse.

  - menus: calling BeginMenu() twice with a same name doesn't append as Begin() does for regular windows (#1207)
  - statusbar: add a per-window status bar helper similar to what menubar does.
  - shortcuts: local-style shortcut api, e.g. parse "&Save"
  - shortcuts,menus: global-style shortcut api e.g. "Save (CTRL+S)" -> explicit flag for recursing into closed menu
  - shortcuts: programmatically access shortcuts "Focus("&Save"))
  - menus: menubars: main menu-bar could affect clamping of windows position (~ akin to modifying DisplayMin)

  - text: proper alignment options in imgui_internal.h
  - text wrapped: figure out better way to use TextWrapped() in an always auto-resize context (tooltip, etc.) (#249)

  - tree node / optimization: avoid formatting when clipped.
  - tree node: tree-node/header right-most side doesn't take account of horizontal scrolling.
  - tree node: add treenode/treepush int variants? not there because (void*) cast from int warns on some platforms/settings?
  - tree node: try to apply scrolling at time of TreePop() if node was just opened and end of node is past scrolling limits?
  - tree node / selectable render mismatch which is visible if you use them both next to each other (e.g. cf. property viewer)
  - tree node: tweak color scheme to distinguish headers from selected tree node (#581)

 !- settings: expose enough to save/load .ini from RAM instead of fopen
  - settings: write more decent code to allow saving/loading new fields
  - settings: api for per-tool simple persistent data (bool,int,float,columns sizes,etc.) in .ini file (#437)
  - stb: add defines to disable stb implementations

 !- style: better default styles.
 !- style: move border to style structure, remove _ShowBorder flag.
  - style: border types: out-screen, in-screen, etc.
  - style/optimization: store rounded corners in texture to use 1 quad per corner (filled and wireframe) to lower the cost of rounding.
  - style: add window shadow (fading away from the window. Paint-style calculation of vertices alpha after drawlist would be easier)
  - style: color-box not always square?
  - style: a concept of "compact style" that the end-user can easily rely on (e.g. PushStyleCompact()?) that maps to other settings? avoid implementing duplicate helpers such as SmallCheckbox(), etc.
  - style: try to make PushStyleVar() more robust to incorrect parameters (to be more friendly to edit & continues situation).
  - style: global scale setting.
  - style: WindowPadding needs to be EVEN as the 0.5 multiplier used on this value probably have a subtle effect on clip rectangle
  - style: have a more global HSV setter (e.g. alter hue on all elements). consider replacing active/hovered by offset in HSV space? (#438, #707, #1223)
  - style: gradients fill (#1223) ~ 2 bg colors for each fill? tricky with rounded shapes and using textures for corners.
  - style editor: color child window height expressed in multiple of line height.

  - log: LogButtons() options for specifying depth and/or hiding depth slider
  - log: have more control over the log scope (e.g. stop logging when leaving current tree node scope)
  - log: be able to log anything (e.g. right-click on a window/tree-node, shows context menu? log into tty/file/clipboard)
  - log: let user copy any window content to clipboard easily (CTRL+C on windows? while moving it? context menu?). code is commented because it fails with multiple Begin/End pairs.

  - filters: set a current filter that tree node can automatically query to hide themselves
  - filters: handle wildcards (with implicit leading/trailing *), regexps
  - filters: fuzzy matches (may use code at blog.forrestthewoods.com/4cffeed33fdb)

  - drag'n drop, dragging helpers, demo (carry dragging info, visualize drag source before clicking, drop target, etc.) (#143, #479)
  - node/graph editor (#306)
  - pie menus patterns (#434)
  - markup: simple markup language for color change?

 !- font: better CalcTextSizeA() API, at least for simple use cases. current one is horrible (perhaps have simple vs extended versions).
  - font: PushFontSize API (#1018)
  - font/atlas: incremental updates
  - font/atlas: dynamic font atlas to avoid baking huge ranges into bitmap and make scaling easier.
  - font/atlas: allow user to submit its own primitive to be rectpacked, and allow to map them on a Unicode point.
  - font: MemoryTTF taking ownership confusing/not obvious, maybe default should be opposite?
  - font/text: vertical and/or rotated text renderer (#705) - vertical is easier clipping wise
  - font: imgui_freetype.h alternative renderer (#618)
  - font: optimization: for monospace font (like the default one) we can trim IndexXAdvance as long as trailing value is == FallbackXAdvance (need to make sure TAB is still correct).
  - font: add support for kerning, probably optional. A) perhaps default to (32..128)^2 matrix ~ 9K entries = 36KB, then hash for non-ascii?. B) or sparse lookup into per-char list?
  - font: add a simpler CalcTextSizeA() api? current one ok but not welcome if user needs to call it directly (without going through ImGui::CalcTextSize)
  - font: fix AddRemapChar() to work before font has been built.
  - font: (api breaking) removed "TTF" from symbol names. also because it now supports OTF.

 !- keyboard: tooltip & combo boxes are messing up / not honoring keyboard tabbing.
  - keyboard: full keyboard navigation and focus. (#323)
  - focus: preserve ActiveId/focus stack state, e.g. when opening a menu and close it, previously selected InputText() focus gets restored (#622)
  - focus: SetKeyboardFocusHere() on with >= 0 offset could be done on same frame (else latch and modulate on beginning of next frame)
  - inputs: rework IO system to be able to pass actual ordered/timestamped events. use an event queue? (~#335, #71)
  - inputs: allow to decide and pass explicit double-clicks (e.g. for windows by the CS_DBLCLKS style).
  - inputs: support track pad style scrolling & slider edit.

  - misc: provide a way to compile out the entire implementation while providing a dummy API (e.g. #define IMGUI_DUMMY_IMPL)
  - misc: provide HoveredTime and ActivatedTime to ease the creation of animations.
  - misc: fix for compilation settings where stdcall isn't the default (e.g. vectorcall) (#1230)
  - remote: make a system like RemoteImGui first-class citizen/project (#75)

  - demo: demo: add a virtual scrolling example?
  - examples: directx9: save/restore device state more thoroughly.
  - examples: window minimize, maximize (#583)
  - examples: provide a zero-framerate/idle example.
  - examples: document WantCaptureKeyboard, WantCaptureMouse in example apps. (#446)
  - optimization: replace vsnprintf with stb_printf? or enable the defines/infrastructure to allow it (#1038)
  - optimization: add clipping for multi-component widgets (SliderFloatX, ColorEditX, etc.). one problem is that nav branch can't easily clip parent group when there is a move request.
  - optimization: add a flag to disable most of rendering, for the case where the user expect to skip it (#335)
  - optimization: use another hash function than crc32, e.g. FNV1a
  - optimization/render: merge command-lists with same clip-rect into one even if they aren't sequential? (as long as in-between clip rectangle don't overlap)?
  - optimization: turn some the various stack vectors into statically-sized arrays
	dear imgui
	ISSUES & TODO LIST

	Issue numbers (#) refer to github issues listed at https://github.com/ocornut/imgui/issues/XXXX
	The list below consist mostly of ideas noted down before they are requested/discussed by users (at which point they usually exist on the github issue tracker).
	It's mostly a bunch of personal notes, probably incomplete. Feel free to query if you have any questions.

	- doc/test: add a proper documentation+regression testing system (#435)
	- doc/test: checklist app to verify binding/integration of imgui (test inputs, rendering, callback, etc.).
	- project: folder or separate repository with maintained helpers (e.g. imgui_memory_editor.h, imgui_stl.h, maybe imgui_dock would be there?)

	- window: calling SetNextWindowSize() every frame with <= 0 doesn't do anything, may be useful to allow (particularly when used for a single axis). (#690)
	- window: add a way for very transient windows (non-saved, temporary overlay over hundreds of objects) to "clean" up from the global window list. perhaps a lightweight explicit cleanup pass.
	- window: auto-fit feedback loop when user relies on any dynamic layout (window width multiplier, column) appears weird to end-user. clarify.
	- window: allow resizing of child windows (possibly given min/max for each axis?.)
	- window: background options for child windows, border option (disable rounding).
	- window: resizing from any sides? + mouse cursor directives for app. (#822)
	!- window: begin with *p_open == false should return false.
	- window: get size/pos helpers given names (see discussion in #249)
	- window: a collapsed window can be stuck behind the main menu bar?
	- window: when window is very small, prioritize resize button over close button.
	- window: detect extra End() call that pop the "Debug" window out and assert at End() call site instead of at end of frame.
	- window/tooltip: allow to set the width of a tooltip to allow TextWrapped() etc. while keeping the height automatic.
	- window: increase minimum size of a window with menus or fix the menu rendering so that it doesn't look odd.
	- window: double-clicking on title bar to minimize isn't consistent, perhaps move to single-click on left-most collapse icon?
	- window: expose contents size. (#1045)
	- window: GetWindowSize() returns (0,0) when not calculated? (#1045)
	!- scrolling: allow immediately effective change of scroll after Begin() if we haven't appended items yet.
	- scrolling/clipping: separator on the initial position of a window is not visible (cursorpos.y <= clippos.y). (2017-08-20: can't repro)

	- drawlist: move Font, FontSize, FontTexUvWhitePixel inside ImDrawList and make it self-contained (apart from drawing settings?)
	- drawlist: make it easier to toggle AA per primitive, so we can use e.g. non-AA fill + AA borders more naturally
	- drawlist: end-user probably can't call Clear() directly because we expect a texture to be pushed in the stack.
	- drawlist: maintaining bounding box per command would allow to merge draw command when clipping isn't relied on (typical non-scrolling window or non-overflowing column would merge with previous command).
	- drawlist: avoid passing null (-9999,+9999) rectangle to end-user, instead perhaps pass rectangle based on io.DisplaySize?
	- drawlist: primtiives/helpers to manipulate vertices post submission, so e.g. a quad/rect can be resized to fit later submitted content, _without_ using the ChannelSplit api

	- main: considering adding an Init() function? some constructs are awkward in the implementation because of the lack of them.
	- main: find a way to preserve relative orders of multiple reappearing windows (so an app toggling between "modes" e.g. fullscreen vs all tools) won't lose relative ordering.
	- main: IsItemHovered() make it more consistent for various type of widgets, widgets with multiple components, etc. also effectively IsHovered() region sometimes differs from hot region, e.g tree nodes
	- main: IsItemHovered() info stored in a stack? so that 'if TreeNode() { Text; TreePop; } if IsHovered' return the hover state of the TreeNode?
	- main: rename the main "Debug" window to avoid ID collision with user who may want to use "Debug" with specific flags.

	- widgets: display mode: widget-label, label-widget (aligned on column or using fixed size), label-newline-tab-widget etc. (#395)
	- widgets: clean up widgets internal toward exposing everything and stabilizing imgui_internals.h.
	- widgets: add disabled and read-only modes (#211)
	- widgets: alignment options in style (e.g. center Selectable, Right-Align within Button, etc.) #1260
	- widgets: activate by identifier (trigger button, focus given id)

	- input text: clean up the mess caused by converting UTF-8 <> wchar. the code is rather inefficient right now and super fragile.
	- input text: reorganize event handling, allow CharFilter to modify buffers, allow multiple events? (#541)
	- input text: expose CursorPos in char filter event (#816)
	- input text: access public fields via a non-callback API e.g. InputTextGetState("xxx") that may return NULL if not active.
	- input text: flag to disable live update of the user buffer (also applies to float/int text input) (#701)
	- input text: way to dynamically grow the buffer without forcing the user to initially allocate for worse case, e.g. more natural std::string (follow up on #200)
	- input text: hover tooltip could show unclamped text
	- input text: add ImGuiInputTextFlags_EnterToApply? (off #218)
	- input text: easier ways to update buffer (from source char*) while owned. preserve some sort of cursor position for multi-line text.
	- input text: add discard flag (e.g. ImGuiInputTextFlags_DiscardActiveBuffer) or make it easier to clear active focus for text replacement during edition (#725)
	- input text: display bug when clicking a drag/slider after an input text in a different window has all-selected text (order dependant). actually a very old bug but no one appears to have noticed it.
	- input text multi-line: don't directly call AddText() which does an unnecessary vertex reserve for character count prior to clipping. and/or more line-based clipping to AddText(). and/or reorganize TextUnformatted/RenderText for more efficiency for large text (e.g TextUnformatted could clip and log separately, etc).
	- input text multi-line: line numbers? status bar? (follow up on #200)
	- input text multi-line: behave better when user changes input buffer while editing is active (even though it is illegal behavior). namely, the change of buffer can create a scrollbar glitch (#725)
	- input text multi-line: better horizontal scrolling support (#383, #1224)
	- input text: allow centering/positioning text so that ctrl+clicking Drag or Slider keeps the textual value at the same pixel position.
	- input number: optional range min/max for Input*() functions
	- input number: holding [-]/[+] buttons could increase the step speed non-linearly (or user-controlled)
	- input number: use mouse wheel to step up/down
	- input number: applying arithmetics ops (+,-,*,/) messes up with text edit undo stack.

	- layout: helper or a way to express ImGui::SameLine(ImGui::GetCursorStartPos().x + ImGui::CalcItemWidth() + ImGui::GetStyle().ItemInnerSpacing.x); in a simpler manner.
	- layout: generalization of the above: a concept equivalent to word processor ruler tab stop ~ mini columns (position in X, no clipping implied) (vaguely relate to #267, #395, also what is used internally for menu items)
	- layout: horizontal layout helper (#97)
	- layout: horizontal flow until no space left (#404)
	- layout: more generic alignment state (left/right/centered) for single items?
	- layout: clean up the InputFloatN/SliderFloatN/ColorEdit4 layout code. item width should include frame padding.
	- layout: BeginGroup() needs a border option.
	- layout: vertical alignement of mixed height items (e.g. buttons) within a same line (#1284)

	- columns: sizing policy (e.g. for each column: fixed size, %, fill, distribute default size among fills) (#513, #125)
	- columns: add a conditional parameter to SetColumnOffset() (#513, #125)
	- columns: headers. with sort op/button. reorderable. (#513, #125)
	- columns: allow columns to recurse.
	- columns: separator function or parameter that works within the column (currently Separator() bypass all columns) (#125)
	- columns: flag to add horizontal separator above/below?
	- columns/layout: setup minimum line height (equivalent of automatically calling AlignFirstTextHeightToWidgets)

	!- color: the color conversion helpers/types are a mess and needs sorting out.
	- color: (api breaking) ImGui::ColorConvertXXX functions should be loose ImColorConvertXX to match imgui_internals.h
	- coloredit: it is still somehow awkward to copy colors around (unless going through Hex mode).

	- plot: full featured plot/graph api w/ scrolling, zooming etc. all bell & whistle. why not!
	- plot: PlotLines() should use the polygon-stroke facilities, less verticles (currently issues with averaging normals)
	- plot: make it easier for user to draw extra stuff into the graph (e.g: draw basis, highlight certain points, 2d plots, multiple plots)
	- plot: "smooth" automatic scale over time, user give an input 0.0(full user scale) 1.0(full derived from value)
	- plot: option/feature: draw the zero line
	- plot: option/feature: draw grid, vertical markers
	- plot: option/feature: draw unit
	- plot: add a helper e.g. Plot(char* label, float value, float time_span=2.0f) that stores values and Plot them for you - probably another function name. and/or automatically allow to plot ANY displayed value (more reliance on stable ID)

	- clipper: ability to force display 1 item in the list would be convenient.

	- splitter/separator: formalize the splitter idiom into an official api (we want to handle n-way split) (#319)

	- dock: docking extension
	- dock: dock out from a collapsing header? would work nicely but need emitting window to keep submitting the code.

	- tabs: re-ordering, close buttons, context menu, persistent order (#261, #351)

	- ext: stl-ish friendly extension (imgui_stl.h) that has wrapped for std::string, std::vector etc.

	- button: provide a button that looks framed.
	- image/image button: misalignment on padded/bordered button?
	- image/image button: parameters are confusing, image() has tint_col,border_col whereas imagebutton() has bg_col/tint_col. Even thou they are different parameters ordering could be more consistent. can we fix that?
	- image button: not taking an explicit id is odd.
	- slider: allow using the [-]/[+] buttons used by InputFloat()/InputInt()
	- slider: initial absolute click is imprecise. change to relative movement slider (same as scrollbar).
	- slider: add dragging-based widgets to edit values with mouse (on 2 axises), saving screen real-estate.
	- slider: tint background based on value (e.g. v_min -> v_max, or use 0.0f either side of the sign)
	- slider: precision dragging
	- slider: step option (#1183)
	- knob: rotating knob widget (#942)
	- slider & drag: int data passing through a float
	- drag float: up/down axis
	- drag float: added leeway on edge (e.g. a few invisible steps past the clamp limits)

	- combo: sparse combo boxes (via function call?) / iterators
	- combo: active item type could be anything else e.g. void*
	- combo: use clipper
	- combo: contents should extends to fit label if combo widget is small
	- combo: option for ComboEx to not return true when unchanged (#1182)
	- combo/listbox: keyboard control. need InputText-like non-active focus + key handling. considering keyboard for custom listbox (pr #203)
	- listbox: multiple selection.
	- listbox: unselect (#1208)
	- listbox: make it easier/more natural to implement range-select (need some sort of info/ref about the last clicked/focused item that user can translate to an index?)
	- listbox: user may want to initial scroll to focus on the one selected value?
	- listbox: expose hovered item for a basic ListBox
	- listbox: keyboard navigation.
	- listbox: scrolling should track modified selection.

	!- popups/menus: clarify usage of popups id, how MenuItem/Selectable closing parent popups affects the ID, etc. this is quite fishy needs improvement! (#331, #402)
	- popups/nav: esc/enter default behavior for popups.
	- popups: reopening context menu at new position should be the behavior by default? (equivalent to internal OpenPopupEx() with reopen_existing=true)
	- popups: if the popup functions took explicit ImGuiID it would allow the user to manage the scope of those ID. (#331)
	- popups: clicking outside (to close popup) and holding shouldn't drag window below.
	- popups: add variant using global identifier similar to Begin/End (#402)
	- popups: border options. richer api like BeginChild() perhaps? (#197)
	- tooltip: tooltip that doesn't fit in entire screen seems to lose their "last preferred direction" and may teleport when moving mouse.

	- menus: calling BeginMenu() twice with a same name doesn't append as Begin() does for regular windows (#1207)
	- statusbar: add a per-window status bar helper similar to what menubar does.
	- shortcuts: local-style shortcut api, e.g. parse "&Save"
	- shortcuts,menus: global-style shortcut api e.g. "Save (CTRL+S)" -> explicit flag for recursing into closed menu
	- shortcuts: programmatically access shortcuts "Focus("&Save"))
	- menus: menubars: main menu-bar could affect clamping of windows position (~ akin to modifying DisplayMin)

	- text: proper alignment options in imgui_internal.h
	- text wrapped: figure out better way to use TextWrapped() in an always auto-resize context (tooltip, etc.) (#249)

	- tree node / optimization: avoid formatting when clipped.
	- tree node: tree-node/header right-most side doesn't take account of horizontal scrolling.
	- tree node: add treenode/treepush int variants? not there because (void*) cast from int warns on some platforms/settings?
	- tree node: try to apply scrolling at time of TreePop() if node was just opened and end of node is past scrolling limits?
	- tree node / selectable render mismatch which is visible if you use them both next to each other (e.g. cf. property viewer)
	- tree node: tweak color scheme to distinguish headers from selected tree node (#581)

	!- settings: expose enough to save/load .ini from RAM instead of fopen
	- settings: write more decent code to allow saving/loading new fields
	- settings: api for per-tool simple persistent data (bool,int,float,columns sizes,etc.) in .ini file (#437)
	- stb: add defines to disable stb implementations

	!- style: better default styles.
	!- style: move border to style structure, remove _ShowBorder flag.
	- style: border types: out-screen, in-screen, etc.
	- style/optimization: store rounded corners in texture to use 1 quad per corner (filled and wireframe) to lower the cost of rounding.
	- style: add window shadow (fading away from the window. Paint-style calculation of vertices alpha after drawlist would be easier)
	- style: color-box not always square?
	- style: a concept of "compact style" that the end-user can easily rely on (e.g. PushStyleCompact()?) that maps to other settings? avoid implementing duplicate helpers such as SmallCheckbox(), etc.
	- style: try to make PushStyleVar() more robust to incorrect parameters (to be more friendly to edit & continues situation).
	- style: global scale setting.
	- style: WindowPadding needs to be EVEN as the 0.5 multiplier used on this value probably have a subtle effect on clip rectangle
	- style: have a more global HSV setter (e.g. alter hue on all elements). consider replacing active/hovered by offset in HSV space? (#438, #707, #1223)
	- style: gradients fill (#1223) ~ 2 bg colors for each fill? tricky with rounded shapes and using textures for corners.
	- style editor: color child window height expressed in multiple of line height.

	- log: LogButtons() options for specifying depth and/or hiding depth slider
	- log: have more control over the log scope (e.g. stop logging when leaving current tree node scope)
	- log: be able to log anything (e.g. right-click on a window/tree-node, shows context menu? log into tty/file/clipboard)
	- log: let user copy any window content to clipboard easily (CTRL+C on windows? while moving it? context menu?). code is commented because it fails with multiple Begin/End pairs.

	- filters: set a current filter that tree node can automatically query to hide themselves
	- filters: handle wildcards (with implicit leading/trailing *), regexps
	- filters: fuzzy matches (may use code at blog.forrestthewoods.com/4cffeed33fdb)

	- drag'n drop, dragging helpers, demo (carry dragging info, visualize drag source before clicking, drop target, etc.) (#143, #479)
	- node/graph editor (#306)
	- pie menus patterns (#434)
	- markup: simple markup language for color change?

	!- font: better CalcTextSizeA() API, at least for simple use cases. current one is horrible (perhaps have simple vs extended versions).
	- font: PushFontSize API (#1018)
	- font/atlas: incremental updates
	- font/atlas: dynamic font atlas to avoid baking huge ranges into bitmap and make scaling easier.
	- font/atlas: allow user to submit its own primitive to be rectpacked, and allow to map them on a Unicode point.
	- font: MemoryTTF taking ownership confusing/not obvious, maybe default should be opposite?
	- font/text: vertical and/or rotated text renderer (#705) - vertical is easier clipping wise
	- font: imgui_freetype.h alternative renderer (#618)
	- font: optimization: for monospace font (like the default one) we can trim IndexXAdvance as long as trailing value is == FallbackXAdvance (need to make sure TAB is still correct).
	- font: add support for kerning, probably optional. A) perhaps default to (32..128)^2 matrix ~ 9K entries = 36KB, then hash for non-ascii?. B) or sparse lookup into per-char list?
	- font: add a simpler CalcTextSizeA() api? current one ok but not welcome if user needs to call it directly (without going through ImGui::CalcTextSize)
	- font: fix AddRemapChar() to work before font has been built.
	- font: (api breaking) removed "TTF" from symbol names. also because it now supports OTF.

	!- keyboard: tooltip & combo boxes are messing up / not honoring keyboard tabbing.
	- keyboard: full keyboard navigation and focus. (#323)
	- focus: preserve ActiveId/focus stack state, e.g. when opening a menu and close it, previously selected InputText() focus gets restored (#622)
	- focus: SetKeyboardFocusHere() on with >= 0 offset could be done on same frame (else latch and modulate on beginning of next frame)
	- inputs: rework IO system to be able to pass actual ordered/timestamped events. use an event queue? (~#335, #71)
	- inputs: allow to decide and pass explicit double-clicks (e.g. for windows by the CS_DBLCLKS style).
	- inputs: support track pad style scrolling & slider edit.

	- misc: provide a way to compile out the entire implementation while providing a dummy API (e.g. #define IMGUI_DUMMY_IMPL)
	- misc: provide HoveredTime and ActivatedTime to ease the creation of animations.
	- misc: fix for compilation settings where stdcall isn't the default (e.g. vectorcall) (#1230)
	- remote: make a system like RemoteImGui first-class citizen/project (#75)

	- demo: demo: add a virtual scrolling example?
	- examples: directx9: save/restore device state more thoroughly.
	- examples: window minimize, maximize (#583)
	- examples: provide a zero-framerate/idle example.
	- examples: document WantCaptureKeyboard, WantCaptureMouse in example apps. (#446)
	- optimization: replace vsnprintf with stb_printf? or enable the defines/infrastructure to allow it (#1038)
	- optimization: add clipping for multi-component widgets (SliderFloatX, ColorEditX, etc.). one problem is that nav branch can't easily clip parent group when there is a move request.
	- optimization: add a flag to disable most of rendering, for the case where the user expect to skip it (#335)
	- optimization: use another hash function than crc32, e.g. FNV1a
	- optimization/render: merge command-lists with same clip-rect into one even if they aren't sequential? (as long as in-between clip rectangle don't overlap)?
	- optimization: turn some the various stack vectors into statically-sized arrays