Feature Request: Ability to render Polyscope viewer in multiple ImGui windows

[sebastienmascha]

Hello Polyscope maintainers and community,

I'm using Polyscope to visualize point cloud data within a GUI application.

Currently, Polyscope encapsulates its own window and event loop and doesn't provide an API to render into multiple ImGui windows. In my case, I would like to show the 3D data in one window alongside 2 other windows to show the two 2D cameras windows. Specifically, I'm looking to render different Polyscope visualizations in separate ImGui windows within the same GUI.

I understand that this feature might involve significant changes to Polyscope's architecture, but I believe the added flexibility would benefit many users and use cases. I look forward to hearing your thoughts on this suggestion.

Thank you for your time and the excellent work on Polyscope!

This is the implementation of two different windows in the same GUI using ImGUI, GLFW and OpenGL3:

// main.cpp
#include "imgui.h"
#include "imgui_impl_glfw.h"
#include "imgui_impl_opengl3.h"
#include <GLFW/glfw3.h>

int main() {
    // Set up window
    glfwInit();
    GLFWwindow* window = glfwCreateWindow(1280, 720, "Hello", NULL, NULL);
    glfwMakeContextCurrent(window);
    glfwSwapInterval(1); // Enable vsync

    // Set up Dear ImGui context
    IMGUI_CHECKVERSION();
    ImGui::CreateContext();
    ImGuiIO& io = ImGui::GetIO();

    // Set up Platform/Renderer bindings
    ImGui_ImplGlfw_InitForOpenGL(window, true);
    ImGui_ImplOpenGL3_Init("#version 130");

    while (!glfwWindowShouldClose(window)) {
        glfwPollEvents();

        // Start ImGui frame
        ImGui_ImplOpenGL3_NewFrame();
        ImGui_ImplGlfw_NewFrame();
        ImGui::NewFrame();

        // Here we construct our GUI
        ImGui::SetNextWindowPos(ImVec2(0, 0));
        ImGui::SetNextWindowSize(ImVec2(640, 720));
        ImGui::Begin("Window 1");
        ImGui::Text("This is window 1");
        ImGui::End();

        ImGui::SetNextWindowPos(ImVec2(640, 0));
        ImGui::SetNextWindowSize(ImVec2(640, 720));
        ImGui::Begin("Window 2");
        ImGui::Text("This is window 2");
        ImGui::End();

        // Render ImGui frame
        ImGui::Render();
        int display_w, display_h;
        glfwGetFramebufferSize(window, &display_w, &display_h);
        glViewport(0, 0, display_w, display_h);
        glClearColor(0.45f, 0.55f, 0.60f, 1.00f);
        glClear(GL_COLOR_BUFFER_BIT);
        ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());

        glfwSwapBuffers(window);
    }

    // Cleanup
    ImGui_ImplOpenGL3_Shutdown();
    ImGui_ImplGlfw_Shutdown();
    ImGui::DestroyContext();

    glfwDestroyWindow(window);
    glfwTerminate();

    return 0;
}

[sebastienmascha]

[adam-hartshorne]

This change would be incredibly useful. Particularly if you could have interoperability between two ImGUI windows i.e. selecting a 2d point on a plot in one window causes a change in the 3d polyscope window. Or even the ability to add in additional ImGUI widgets in the way you can add additional controls in the exposed callback method.