imgui glfw3 GLEQ eventhandler

[AnimatorJeroen]

Not really an issue, but I'd like to share a code snippet for people using imgui with GLEQ.

GLEQ is a simple (SDL like) event queue for GLFW3. It replaces all the callbacks of the glfw window, so keyboard-, textinput and scrollinput in ImGui will be lost.

To get my inputs back in dear ImGui, I made a "ProcessEvent" function, derived from: ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)

Run this function in the while gleqNextEvent() loop:

bool ProcessEvent(GLEQevent* event)
{
	ImGuiIO& io = ImGui::GetIO();
	switch (event->type)
	{
		case GLEQ_SCROLLED:
		{
			if (event->scroll.x > 0) io.MouseWheelH += 1;
			if (event->scroll.x < 0) io.MouseWheelH -= 1;
			if (event->scroll.y > 0) io.MouseWheel += 1;
			if (event->scroll.y < 0) io.MouseWheel -= 1;
			return true;
		}
		case GLEQ_BUTTON_PRESSED:
		{
			if (event->mouse.button == 0) io.MouseDown[0] = true;
			if (event->mouse.button == 1) io.MouseDown[1] = true;
			if (event->mouse.button == 2) io.MouseDown[2] = true;
			return true;
		}
                case GLEQ_CODEPOINT_INPUT:
		{
			//io.AddInputCharactersUTF8(event->codepoint);
                        io.AddInputCharacter(event->codepoint);
			return true;
		}
		case GLEQ_KEY_PRESSED:
		case GLEQ_KEY_RELEASED:
		{
            //std::cout << (event->keyboard.mods) << std::endl;
			int key = event->keyboard.key;
			IM_ASSERT(key >= 0 && key < IM_ARRAYSIZE(io.KeysDown));
			io.KeysDown[key] = (event->type == GLEQ_KEY_PRESSED);
                        io.KeyShift = (event->keyboard.mods == 1);
			io.KeyCtrl = (event->keyboard.mods == 2);
			io.KeyAlt = (event->keyboard.mods == 4);
			io.KeySuper = (event->keyboard.mods == 8);
			return true;
		}
	}
	return false;
}

[ocornut]

Hello,

Thanks for posting it. At a quick glance it seems like mouse buttons are never marked as released?

About

It replaces all the callbacks of the glfw window, so keyboard-, textinput and scrollinput in ImGui will be lost

I think it would be more appropriate to just chain the callback.
If you installed GLEQ callbacks gleqTrackWindow() and then install the imgui glfw backend callbacks, the later will automatically call the GLEQ callbacks while handling its own stuff. You could also do it the other way.

[AnimatorJeroen]

Ah that makes a lot of sense.
I tried it and got all the input back in ImGui.
So no more need for this function!
Thank you ocornut!