Updating backend ImGui/ImPlot/ImNodes to latest versions

[SamuMazzi]

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name: Updating backend ImGui/ImPlot/ImNodes about: Updated backends title: Updating backend ImGui/ImPlot/ImNodes assignees: ''

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After a loooooot of work and time, we've finally finished the PR. A huge thank you to @v-ein for all the help and support.

Description

This PR aims to update the ImGui/ImPlot/ImNodes backends of DPG to way more recent versions.

Currently, DPG relies on really old version of these packages (~2/3 years old), now this is the situation before/after the PR:

• ImGui: 1.83 (May 2021) -> 1.91.0 (July 2024)
• ImPlot: 0.11 (May 2021) -> 0.17 (January 2024)
• ImNodes: 0.5 (April 2022) -> updated to the latest available (March 2024)

Those versions are the latest available at the moment of merging the PR and they are supported by DPG but this doesn't mean that we implemented every single feature from those libraries (many are still missing like multi-selection, several flags in different components, new API for shortcuts, etc...).

Below will be listed a summary of the major changes and new features. We tried to be as much backward compatible as possible. And hopefully you may not need to change anything in your current code.

Issues solved

• Fix #2173, #2013, #1593 (last 2 issues are closed but not solved, but they are all related)
• Fix #2108
• Fix #2016

Changes

• Now there can be 3 x-axes other than the currently supported 3 y-axes
• New StackToolWindow
• New query API for plots. Now multiple queries can be created and managed. Check the demo and the new parameters in add_plot to have more info
• Now label parameter in add_separator will put a label inside the separator
• ctrl + tab navigation across windows independent from keyboard_navigation parameter
• Add Presentation section to MetricsTool like in the original ImGui
• enable parameter in add_group will apply mvStyleVar_DisabledAlpha to all its children

Here is a list of all the new and deprecated arguments and functions.

Note: all deprecated functions and arguments are still accepted by DearPyGui API. Some of them may still work, some are ignored, but none should crash your application.

New functions

• add_axis_tag
• add_bar_group_series
• add_inf_line_series
• add_digital_series
• get_plot_query_rects
• set_axis_limits_constraints
• reset_axis_limits_constraints
• set_axis_zoom_constraints
• reset_axis_zoom_constraints

New arguments

Function	Arguments
add_2d_histogram_series	col_major
add_button	repeat
add_child_window	always_auto_resize always_use_window_padding auto_resize_x auto_resize_y frame_style resizable_x resizable_y
add_colormap_scale	format mirror reverse_dir
add_combo	fit_width
add_custom_series	no_fit
add_drag_line	delayed no_cursor no_fit no_inputs
add_drag_point	clamped delayed no_cursor no_fit no_inputs offset
add_group	enabled
add_heat_series	col_major
add_histogram_series	cumulative horizontal
add_input_text	always_overwrite auto_select_all ctrl_enter_for_new_line escape_clears_all no_horizontal_scroll no_undo_redo
add_line_series	loop no_clip segments shaded skip_nan
add_pie_series	ignore_hidden
add_plot	max_query_rects min_query_rects no_frame no_inputs override_mod query_color zoom_mod zoom_rate
add_plot_axis	auto_fit foreground_grid no_highlight no_initial_fit no_label no_menus no_side_switch opposite pan_stretch range_fit scale tick_format
add_plot_legend	no_buttons no_highlight_axis no_highlight_item no_menus sort
add_scatter_series	no_clip
add_stair_series	pre_step shaded
add_stem_series	horizontal
add_subplots	share_series
add_table_column	angled_header no_header_label
add_text_point	offset
add_tree_node	span_full_width span_text_width
add_window	unsaved_document
configure_app	anti_aliased_fill anti_aliased_lines anti_aliased_lines_use_tex docking_shift_only

Deprecated functions

• add_hline_series: use add_inf_line_series()
• add_vline_series: use add_inf_line_series()
• get_plot_query_area: use get_plot_query_rects()
• is_plot_queried: use get_plot_query_rects()

Deprecated arguments

Function	Argument	Explanation
add_histogram_series	cumlative	Deprecated because of a typo: use cumulative
add_image_button	frame_padding	Not supported anymore by Dear ImGui; still works in DPG but will eventually be removed.
add_plot	anti_aliased	Not supported by ImPlot anymore. To enable/disable anti-aliasing, use dpg.configure_app() with the anti_aliasing parameters.
add_plot	no_child	Removed in ImPlot as child windows are no longer needed to capture scroll.
add_plot	no_highlight	Removed because not supported by ImPlot anymore. To control the highlighting of series use the same argument in add_plot_legend.
add_plot	query_button query_mod	This refers to the old way of querying in ImPlot, now replaced with add_drag_rect().
add_plot_axis	log_scale	Use scale=dpg.mvPlotScale_Log10 instead.
add_plot_axis	time	Use scale=dpg.mvPlotScale_Time instead.
add_text_point	x_offset y_offset	Use the offset argument instead.

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Nerd info (for developers)

Why?

ImGui is currently sponsored by big tech companies like Adobe, Blizzard, Activision, etc. so we can expect a lot of improvements with the update (there are already ton of them) and we can expect a lot of people working on the really ugly/hard things like graphical backend libraries.

At my workplace we are about to ship a product based on DPG. Because of my job, I had to edit the backend and then I found out that what I edited was already modified in the new ImGui and then I also found out that the ImGui version we were relying on in DPG was really old. We want to stick with this library but I honestly told them that I don't see the point of relying on an almost dead (okay, no, maintenance mode) library, so we decided to either upgrade it or drop it and replace it with something else.

I know that this is quite a huge change, and that several problems can arise but I also think that it can be definitely worth it. Also with this huge community all of these changes can be "easily" tested.

OpenGL

Currently, for the build, DPG relies on gl3w in the examples folder of ImGui. This doesn't sound like a really stable thing and indeed a couple of releases later, that's been removed, so I added gl3w directly in the thirdparty folder. Also ImGui decided to make some heavy changes in order to be more cross-platform. One of these, which is also my biggest concern about all of this work, is about the buttons of the keyboard. These are now less than before, and they have been all mapped to predefined values in ImGui. So if someone used them heavily now they could have some problem.

Major concerns

• As I said earlier, now there are less keyboard buttons than before, I think that they'll add more in the future, but I don't know how to solve this problem.
• In my workplace we have never used ImNodes so we haven't tested that a lot. There haven't been any huge updates during these years so there shouldn't be a lot (or any) problems. If someone's willing to help and take a look, they'd be welcome.

Notes

There are still tons of updates and new features that can be implemented (i.e. Shortcuts API, Multi select, and many others), then if you want to take a look on what happened check this for ImPlot and ImGui

In ~2022 ImGui moved all the docking stuff in a separate branch, so now we're relying on that branch. This is not a big difference because it's always rebased on the main branch on every update and should be merged in the master in the version 2.0

Everything was tested with Valgrind in order to be sure that there wasn't any kind of accidental memory leak (or at least not more than those who were already there).

My main goal here was to have a real feedback from the most expert users on this work.

I hope I was clear enough! I'd like to improve this library because I think it's really great, so any kind of suggestion will be well accepted.