Why is the API different from ImGui?

[epitaque]

The IMGUI code lives inside a loop that runs once per frame like this:

ImGui::Begin("My First Tool", &my_tool_active, ImGuiWindowFlags_MenuBar);
ImGui::TextColored(time());
ImGui::End();

This is great because you don't have to worry about state synchronization stuff, because every frame you are calling ImGUI::whatever with current data.

This is in contrast to DearPyGui, where you have some setup code and then an loop that runs once per frame:

import dearpygui.dearpygui as dpg

dpg.create_context()
dpg.create_viewport()
dpg.setup_dearpygui()

with dpg.window(label="Example Window"):
    a_tag = dpg.add_text("Hello world")

while dpg.is_dearpygui_running():
  dpg.set_value(a_tag, dpg.get_total_time())

dpg.show_viewport()
dpg.start_dearpygui()
dpg.destroy_context()

The key thing that made ImGui so great is that you didn't have to worry about UI state, since the UI was kinda reconstructed every frame (from the developer's POV). Now that is not to knock Dear PyGUI, it is still miles better than all the other Python gui libraries. I am just wondering why you went with this style of API?

[hoffstadt]

You are preaching to the choir!

There are several reasons we initially went with the API design but the most important one is we didn't realize how much more powerful the immediate mode API was at the time. I've been using Dear ImGui now daily for years and I see my error. This is one of the main reasons we are working on a DPG 2 which will be closer to the Dear ImGui API. Actually, it will almost be a 1 to 1 mapping.

So stick around for that!

[hoffstadt]

Also worth mentioning, my opinions and coding style have changed dramatically since I started this project.

I've moved to keeping things much simpler and pretty much just use C99 now. I'm also working on a separate UI (as part of a simple engine) that I plan on using for DPG 3. You can see that here.

[epitaque]

Thanks for the reply! Looking forward to DPG 2

[eparker-adaptive3d]

Thank you, thank you, thank you! I would love to see all the great features and extras from DearPyGui, but in immediate mode. My current project using pyimgui depends on immediate mode, but I've salivated over the capabilities of DearPyGui (just the file open/save dialog would make a huge difference). Looking forward to it!