Mouse input from PDCurses application not working

[thomthom]

Environment

Windows build number: Microsoft Windows [Version 10.0.19041.450]
Windows Terminal version (if applicable): 1.2.2381.0

Any other software?
PDCurses: https://github.com/wmcbrine/PDCurses @ 618e0aa

Steps to reproduce

# CMakeLists.txt
cmake_minimum_required(VERSION 3.17)

project(CursesTest VERSION 0.1.0 LANGUAGES CXX C)

find_package(Curses REQUIRED)

set(MOUSECURSE_SOURCES
  mousecurse.cpp
)

add_executable(mousecurse ${MOUSECURSE_SOURCES})
target_link_libraries(mousecurse
  curses
)
target_compile_definitions(mousecurse PRIVATE PDC_NCMOUSE)

// mousecurse.cpp
#include <iomanip>
#include <iostream>

#include <curses.h>

void print_input(int input);

int main()
{
  initscr();
  raw();
  keypad(stdscr, TRUE);
  noecho();

  mousemask(BUTTON1_CLICKED, nullptr);

  move(1, 1);
  attron(A_BOLD);
  printw("PDCurses Mouse Test");
  attroff(A_BOLD);

  bool run = true;
  while(run) {
    refresh();
    int input = getch();

    switch(input) {
    case 'q':
      run = false;
      break;
    default:
      print_input(input);
    }
  }

  endwin();
  return 0;
}

void print_input(int input)
{
  move(3, 1);
  clrtoeol();
  printw("The pressed key is ");
  attron(A_BOLD);
  if (input & KEY_CODE_YES) {
    const char* name = keyname(input);
    printw("%i (%s)", input, name);

  } else if (input == KEY_MOUSE) {
    MEVENT event{};
    if(getmouse(&event) == OK) {
      const char* name = keyname(input);
      printw("%i (%s) [x: %i, y: %i, state: %lu]",
          input, name, event.x, event.y, event.bstate);
    }

  } else {
    printw("%i (%c)", input, input);
  }
  attroff(A_BOLD);
}

Expected behavior

I'm expecting the receive mouse input to the application. This works in normal cmd.exe:

Actual behavior

In Windows Terminal the mouse events doesn't reach the application, instead a text selection is made:

[jdebp]

If it helps in diagnosis, PDCurses uses ReadConsoleInput() to read mouse input events. https://github.com/wmcbrine/PDCurses/blob/48b0c1297529758a10a68aca0f904f90893f165d/wincon/pdckbd.c#L575

[DHowett]

So, this is a /duplicate of #376! PDCurses applications are Windows applications using the Win32 console APIs to read mouse events, and we don't currently have support in the translation layer (which is also used by ssh and other terminal emulators on Windows) for translating Win32 mouse events from VT mouse events.

[ghost]

Hi! We've identified this issue as a duplicate of another one that already exists on this Issue Tracker. This specific instance is being closed in favor of tracking the concern over on the referenced thread. Thanks for your report!

[thomthom]

Ok, I'm subscribing to the other issue. Thanks for confirming.

Are there other libraries that are currently able to achieve this in Windows Terminal? (PDCurses was the main library I found that has a working Windows implementation. ncurses seems to not support Windows.)

[DHowett]

That's a good question. I'm not sure of that off the top of my head...
In general, anything that wants to use VT is going to be a little easier to wrangle, and be a bit more cross-platform, but was likely not originally developed for Windows. 😄

[thomthom]

What does "VT" stand for?

[DHowett]

Ah, sorry. "Virtual Terminal". I typically call the in-band signalling sequences that terminals use to communicate (and applications use to communicate with terminals) "VT", though I can't determine why I do that. They do things like set color, request input mode changes ("encode these keys differently", "i want mouse input", etc.), and a whole heap of other things.

Broadly and loosely, they're the cross-platform alternative to the Win32 console APIs. Where somebody might say SetConsoleTextAttribute(FOREGROUND_RED) on Windows, they might print out the string \e[31m everywhere else.

[DHowett]

(This is very broad, and very loose, but it serves to illustrate the point. jdebp could almost certainly furnish a better explanation than the one that I spent 50 seconds on 😄)

[thomthom]

So, I could use this "Virtual Terminal" from my app to get mouse events in Windows Terminal, as a workaround until WT supports it?

If so, what APIs would I be looking at?

[jdebp]

"VT" in this context usually comes from the product names of the DEC VT range of computer terminals, the VT05 to the VT525. It stands for "video terminal", in opposition to a paper or a hardcopy terminal.