basic.py

# -*- coding: utf-8 -*-
from sdl2 import *
import ctypes
import OpenGL.GL as gl

import imgui
from imgui.integrations.sdl2 import SDL2Renderer
from testwindow import show_test_window


def main():
    window, gl_context = impl_pysdl2_init()
    imgui.create_context()
    impl = SDL2Renderer(window)

    running = True
    event = SDL_Event()
    while running:
        while SDL_PollEvent(ctypes.byref(event)) != 0:
            if event.type == SDL_QUIT:
                running = False
                break
            impl.process_event(event)
        impl.process_inputs()

        imgui.new_frame()

        if imgui.begin_main_menu_bar():
            if imgui.begin_menu("File", True):

                clicked_quit, selected_quit = imgui.menu_item(
                    "Quit", 'Cmd+Q', False, True)

                if clicked_quit:
                    exit(1)

                imgui.end_menu()
            imgui.end_main_menu_bar()

        show_test_window()
        #imgui.show_test_window()

        imgui.begin("Custom window", True)
        imgui.text("Bar")
        imgui.text_colored("Eggs", 0.2, 1., 0.)
        imgui.end()

        gl.glClearColor(1., 1., 1., 1)
        gl.glClear(gl.GL_COLOR_BUFFER_BIT)

        imgui.render()
        impl.render(imgui.get_draw_data())
        SDL_GL_SwapWindow(window)

    impl.shutdown()
    SDL_GL_DeleteContext(gl_context)
    SDL_DestroyWindow(window)
    SDL_Quit()


def impl_pysdl2_init():
    width, height = 1280, 720
    window_name = "minimal ImGui/SDL2 example"

    if SDL_Init(SDL_INIT_EVERYTHING) < 0:
        print("Error: SDL could not initialize! SDL Error: " +
              SDL_GetError().decode("utf-8"))
        exit(1)

    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1)
    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24)
    SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8)
    SDL_GL_SetAttribute(SDL_GL_ACCELERATED_VISUAL, 1)
    SDL_GL_SetAttribute(SDL_GL_MULTISAMPLEBUFFERS, 1)
    SDL_GL_SetAttribute(SDL_GL_MULTISAMPLESAMPLES, 16)
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS,
                        SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG)
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 4)
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1)
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,
                        SDL_GL_CONTEXT_PROFILE_CORE)

    SDL_SetHint(SDL_HINT_MAC_CTRL_CLICK_EMULATE_RIGHT_CLICK, b"1")
    SDL_SetHint(SDL_HINT_VIDEO_HIGHDPI_DISABLED, b"1")

    window = SDL_CreateWindow(window_name.encode('utf-8'),
                              SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
                              width, height,
                              SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE)

    if window is None:
        print("Error: Window could not be created! SDL Error: " +
              SDL_GetError().decode("utf-8"))
        exit(1)

    gl_context = SDL_GL_CreateContext(window)
    if gl_context is None:
        print("Error: Cannot create OpenGL Context! SDL Error: " +
              SDL_GetError().decode("utf-8"))
        exit(1)

    SDL_GL_MakeCurrent(window, gl_context)
    # if SDL_GL_SetSwapInterval(1) == -1:
    #     print("Warning: Unable to set VSync! SDL Error: " +
    #           SDL_GetError().decode("utf-8"))

    #     if SDL_GL_SetSwapInterval(-1) == -1:
    #         print("Warning: Unable to set adaptive VSync! SDL Error: " +
    #               SDL_GetError().decode("utf-8"))

    #         if SDL_GL_SetSwapInterval(0) == -1:
    #             print("Warning: Unable to set immediate mode! " +
    #                   SDL_GetError().decode("utf-8"))

    print('Swap interval:', SDL_GL_GetSwapInterval())
    # print('interval', interval)
    # if SDL_GL_SetSwapInterval(1):
    #     print("Warning: Unable to set VSync! SDL Error: " +
    #           SDL_GetError().decode("utf-8"))
    #     exit(1)

    return window, gl_context


if __name__ == "__main__":
    main()