Change from ui_hooks_t to a pure virtual interface Frontend

10 files changed, 625 insertions, 649 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 2aa2f7c5..6c9ca9d6 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -26,6 +26,7 @@ SET(SRCS_COMMON
   dice.cc
   dungeon.cc
   files.cc
+  frontend.cc
   format_ext.cc
   game.cc
   game_edit_data.cc
diff --git a/src/frontend.cc b/src/frontend.cc
new file mode 100644
index 00000000..2194ff21
--- /dev/null
+++ b/src/frontend.cc
@@ -0,0 +1 @@
+#include "frontend.hpp"
diff --git a/src/frontend.hpp b/src/frontend.hpp
new file mode 100644
index 00000000..7a2d95aa
--- /dev/null
+++ b/src/frontend.hpp
@@ -0,0 +1,112 @@
+#pragma once
+
+#include "frontend_fwd.hpp"
+
+#include <string_view>
+
+#include "h-basic.hpp"
+
+/**
+ * User interface operations supported by the front end.
+ */
+class Frontend {
+
+public:
+	/**
+	 * Result polling/waiting for an event.
+	 */
+	enum class event_result_t {
+		SUCCESS,
+		FAILURE,
+	};
+
+	/**
+	 * Initialize the underlying user interface element.
+	 */
+	virtual void init() = 0;
+
+	/**
+	 * Destroy the underlying user interface element.
+	 */
+	virtual void nuke() = 0;
+
+	/**
+	 * Poll or wait for event and process it.
+	 */
+	virtual void process_event(bool wait) = 0;
+
+	/**
+	 * Does this user interface draw its own cursor?
+	 *
+	 * The return value is assumed to be constant over the
+	 * lifetime of the user interface.
+	 */
+	virtual bool soft_cursor() const = 0;
+
+	/**
+	 * Does this user interface have an "icky" lower right corner,
+	 * i.e. does it _not_ support putting the cursor in that corner?
+	 *
+	 * The return value is assumed to be constant over the
+	 * lifetime of the user interface.
+	 */
+	virtual bool icky_corner() const = 0;
+
+	/**
+	 * Flush any pending events.
+	 */
+	virtual void flush_events() = 0;
+
+	/**
+	 * Process any pending events.
+	 */
+	virtual void process_queued_events() = 0;
+
+	/**
+	 * Clear contents of the user interface.
+	 */
+	virtual void clear() = 0;
+
+	/**
+	 * Flush pending output.
+	 */
+	virtual void flush_output() = 0;
+
+	/**
+	 * Make a noise, e.g. a system beep or similar.
+	 */
+	virtual void noise() = 0;
+
+	/**
+	 * React to changes generated by the game, e.g. window
+	 * size, or colors.
+	 */
+	virtual void react() = 0;
+
+	/**
+	 * Signal the activation/deactivation of the user interface.
+	 */
+	virtual void activate_deactivate(bool resume) = 0;
+
+	/**
+	 * Rename the main window.
+	 */
+	virtual void rename_main_window(std::string_view) = 0;
+
+	/**
+	 * Draw the cursor at position x, y.
+	 */
+	virtual void draw_cursor(int x, int y) = 0;
+
+	/**
+	 * Draw the given text string s at position x, y
+	 * using attributes a.
+	 */
+	virtual void draw_text(int x, int y, int n, byte a, const char *s) = 0;
+
+	/**
+	 * Destroy.
+	 */
+	virtual ~Frontend() = default;
+
+};
diff --git a/src/frontend_fwd.hpp b/src/frontend_fwd.hpp
new file mode 100644
index 00000000..925cfa5e
--- /dev/null
+++ b/src/frontend_fwd.hpp
@@ -0,0 +1,3 @@
+ #pragma once
+
+class Frontend;
diff --git a/src/main-gcu.cc b/src/main-gcu.cc
index 9fb7724f..bc6b9ab1 100644
--- a/src/main-gcu.cc
+++ b/src/main-gcu.cc
@@ -39,6 +39,7 @@
  */
 
 #include "main.hpp"
+#include "frontend.hpp"
 #include "variable.hpp"
 #include "z-util.hpp"
 
@@ -205,12 +206,6 @@ static term_data data[MAX_TERM_DATA];
 
 
 /*
- * Hack -- Number of initialized "term" structures
- */
-static int active = 0;
-
-
-/*
  * Hack -- define "A_BRIGHT" to be "A_BOLD", because on many
  * machines, "A_BRIGHT" produces ugly "inverse" video.
  */
@@ -430,219 +425,240 @@ static void keymap_game_prepare()
 
 
 /*
- * Init the "curses" system
+ * React to changes
  */
-static void Term_init_gcu(void *data)
+static void Term_xtra_gcu_react()
 {
-	term_data *td = (term_data *) data;
 
-	/* Count init's, handle first */
-	if (active++ != 0) return;
-
-	/* Erase the window */
-	(void)wclear(td->win);
+	int i;
 
-	/* Reset the cursor */
-	(void)wmove(td->win, 0, 0);
+	/* Cannot handle color redefinition */
+	if (!can_fix_color)
+	{
+		return;
+	}
 
-	/* Flush changes */
-	(void)wrefresh(td->win);
+	/* Set the colors */
+	for (i = 0; i < 16; i++)
+	{
+		/* Set one color (note scaling) */
+		init_color(i,
+		           angband_color_table[i][1] * 1000 / 255,
+		           angband_color_table[i][2] * 1000 / 255,
+		           angband_color_table[i][3] * 1000 / 255);
+	}
 
-	/* Game keymap */
-	keymap_game();
 }
 
 
 /*
- * Nuke the "curses" system
+ * User Interface for GCU.
  */
-static void Term_nuke_gcu(void *data)
-{
-	int x, y;
-	term_data *td = (term_data *) data;
+class CursesFrontend final : public Frontend {
 
-	/* Delete this window */
-	delwin(td->win);
+	/*
+	 * Hack -- Number of initialized "term" structures
+	 */
+	static int m_active;
 
-	/* Count nuke's, handle last */
-	if (--active != 0) return;
+private:
+	term_data *m_term_data;
 
-	/* Reset colors to defaults */
-	start_color();
+	bool event_aux(bool wait)
+	{
+		int i, k;
 
-	/* Get current cursor position */
-	getyx(curscr, y, x);
+		char buf[2];
 
-	/* Move the cursor to bottom right corner */
-	mvcur(y, x, LINES - 1, 0);
+		/* Wait */
+		if (wait)
+		{
+			/* Wait for one byte */
+			i = read(0, buf, 1);
 
-	/* Flush the curses buffer */
-	(void)refresh();
+			/* Hack -- Handle bizarre "errors" */
+			if ((i <= 0) && (errno != EINTR)) abort();
+		}
 
-	/* Exit curses */
-	endwin();
+		/* Do not wait */
+		else
+		{
+			/* Get the current flags for stdin */
+			k = fcntl(0, F_GETFL, 0);
 
-	/* Flush the output */
-	(void)fflush(stdout);
+			/* Oops */
+			if (k < 0)
+			{
+				return false;
+			}
 
-	/* Normal keymap */
-	keymap_norm();
-}
+			/* Tell stdin not to block */
+			if (fcntl(0, F_SETFL, k | O_NDELAY) < 0)
+			{
+				return false;
+			}
 
+			/* Read one byte, if possible */
+			i = read(0, buf, 1);
 
-/*
-* Process events (with optional wait)
-*/
-static errr Term_xtra_gcu_event(int v)
-{
-	int i, k;
+			/* Replace the flags for stdin */
+			if (fcntl(0, F_SETFL, k))
+			{
+				return false;
+			}
+		}
 
-	char buf[2];
+		/* Ignore "invalid" keys */
+		if ((i != 1) || (!buf[0]))
+		{
+			return false;
+		}
 
-	/* Wait */
-	if (v)
-	{
-		/* Wait for one byte */
-		i = read(0, buf, 1);
+		/* Enqueue the keypress */
+		Term_keypress(buf[0]);
 
-		/* Hack -- Handle bizarre "errors" */
-		if ((i <= 0) && (errno != EINTR)) abort();
+		/* Success */
+		return true;
 	}
 
-	/* Do not wait */
-	else
+public:
+	explicit CursesFrontend(term_data *term_data)
+		: m_term_data(term_data)
 	{
-		/* Get the current flags for stdin */
-		k = fcntl(0, F_GETFL, 0);
+	}
 
-		/* Oops */
-		if (k < 0) return (1);
+	void init() final
+	{
+		/* Count init's, handle first */
+		if (m_active++ != 0) return;
 
-		/* Tell stdin not to block */
-		if (fcntl(0, F_SETFL, k | O_NDELAY) < 0) return (1);
+		/* Clear */
+		wclear(m_term_data->win);
+		wmove(m_term_data->win, 0, 0);
+		wrefresh(m_term_data->win);
 
-		/* Read one byte, if possible */
-		i = read(0, buf, 1);
+		/* Game keymap */
+		keymap_game();
+	};
 
-		/* Replace the flags for stdin */
-		if (fcntl(0, F_SETFL, k)) return (1);
+	bool icky_corner() const final
+	{
+		return true;
 	}
 
-	/* Ignore "invalid" keys */
-	if ((i != 1) || (!buf[0])) return (1);
+	bool soft_cursor() const final
+	{
+		return false;
+	}
 
-	/* Enqueue the keypress */
-	Term_keypress(buf[0]);
+	void nuke() final
+	{
+		/* Delete this window */
+		delwin(m_term_data->win);
 
-	/* Success */
-	return (0);
-}
+		/* Count nuke's, handle last */
+		if (--m_active != 0) return;
 
+		/* Reset colors to defaults */
+		start_color();
 
-/*
- * React to changes
- */
-static void Term_xtra_gcu_react()
-{
+		/* Get current cursor position */
+		int x, y;
+		getyx(curscr, y, x);
 
-	int i;
+		/* Move the cursor to bottom right corner */
+		mvcur(y, x, LINES - 1, 0);
 
-	/* Cannot handle color redefinition */
-	if (!can_fix_color)
-	{
-		return;
-	}
+		/* Flush the curses buffer */
+		refresh();
 
-	/* Set the colors */
-	for (i = 0; i < 16; i++)
-	{
-		/* Set one color (note scaling) */
-		init_color(i,
-		           angband_color_table[i][1] * 1000 / 255,
-		           angband_color_table[i][2] * 1000 / 255,
-		           angband_color_table[i][3] * 1000 / 255);
-	}
+		/* Exit curses */
+		endwin();
 
-}
+		/* Flush the output */
+		fflush(stdout);
 
+		/* Normal keymap */
+		keymap_norm();
+	}
 
-/*
- * Handle a "special request"
- */
-static void Term_xtra_gcu(void *data, int n, int v)
-{
-	term_data *td = (term_data *) data;
+	void process_event(bool wait) final
+	{
+		event_aux(wait);
+	}
 
-	/* Analyze the request */
-	switch (n)
+	void flush_events() final
 	{
-		/* Clear screen */
-	case TERM_XTRA_CLEAR:
-		touchwin(td->win);
-		(void)wclear(td->win);
-		return;
+		while (event_aux(false))
+		{
+			// Keep flushing
+		}
+	}
 
-		/* Make a noise */
-	case TERM_XTRA_NOISE:
-		(void)write(1, "\007", 1);
-		return;
+	void clear() final
+	{
+		touchwin(m_term_data->win);
+		wclear(m_term_data->win);
+	}
 
-		/* Flush the Curses buffer */
-	case TERM_XTRA_FRESH:
-		(void)wrefresh(td->win);
-		return;
+	void flush_output() final
+	{
+		wrefresh(m_term_data->win);
+	}
 
-		/* Process events */
-	case TERM_XTRA_EVENT:
-		Term_xtra_gcu_event(v);
-		return;
+	void noise() final
+	{
+		write(1, "\007", 1);
+	}
 
-		/* Flush events */
-	case TERM_XTRA_FLUSH:
-		while (!Term_xtra_gcu_event(false));
-		return;
+	void process_queued_events() final
+	{
+		// No action necessary
+	}
 
-		/* React to events */
-	case TERM_XTRA_REACT:
+	void react() final
+	{
 		Term_xtra_gcu_react();
-		return;
 	}
-}
 
+	void activate_deactivate(bool) final
+	{
+		// No action necessary
+	}
 
-/*
- * Actually MOVE the hardware cursor
- */
-static void Term_curs_gcu(void *data, int x, int y)
-{
-	term_data *td = (term_data *) data;
+	void rename_main_window(std::string_view) final
+	{
+		// Don't have window titles
+	}
 
-	/* Literally move the cursor */
-	wmove(td->win, y, x);
-}
+	void draw_cursor(int x, int y) final
+	{
+		wmove(m_term_data->win, y, x);
+	}
 
+	void draw_text(int x, int y, int n, byte a, const char *s) final
+	{
+		/* Set the color */
+		if (can_use_color)
+		{
+			wattrset(m_term_data->win, colortable[a & 0x0F]);
+		}
 
-/*
- * Place some text on the screen using an attribute
- */
-static void Term_text_gcu(void *data, int x, int y, int n, byte a, const char *s)
-{
-	term_data *td = (term_data *) data;
+		/* Move the cursor */
+		wmove(m_term_data->win, y, x);
 
-	/* Set the color */
-	if (can_use_color) wattrset(td->win, colortable[a & 0x0F]);
+		/* Draw each character */
+		for (int i = 0; i < n; i++)
+		{
 
-	/* Move the cursor */
-	wmove(td->win, y, x);
+			/* Draw a normal character */
+			waddch(m_term_data->win, (byte)s[i]);
+		}
+	}
 
-	/* Draw each character */
-	for (int i = 0; i < n; i++)
-	{
+};
 
-		/* Draw a normal character */
-		waddch(td->win, (byte)s[i]);
-	}
-}
+int CursesFrontend::m_active = 0;
 
 
 /*
@@ -662,19 +678,8 @@ static errr term_data_init_gcu(term_data *td, int rows, int cols, int y, int x)
 		quit("Failed to setup curses window.");
 	}
 
-	/* Hooks */
-	struct term_ui_hooks_t ui_hooks = {
-		Term_init_gcu,
-		Term_nuke_gcu,
-		Term_xtra_gcu,
-		Term_curs_gcu,
-		Term_text_gcu,
-	};
-
 	/* Initialize the term */
-	td->term_ptr = term_init(td, cols, rows, 256);
-	term_init_icky_corner(td->term_ptr);
-	term_init_ui_hooks(td->term_ptr, ui_hooks);
+	td->term_ptr = term_init(cols, rows, 256, std::make_shared<CursesFrontend>(td));
 
 	/* Activate it */
 	Term_activate(td->term_ptr);
@@ -684,12 +689,8 @@ static errr term_data_init_gcu(term_data *td, int rows, int cols, int y, int x)
 }
 
 
-static void hook_quit(const char *str)
+static void hook_quit(const char *)
 {
-	/* Unused */
-	(void)str;
-
-	/* Exit curses */
 	endwin();
 }
 
diff --git a/src/main-gtk2.cc b/src/main-gtk2.cc
index 510c72fd..d75109f3 100644
--- a/src/main-gtk2.cc
+++ b/src/main-gtk2.cc
@@ -32,6 +32,7 @@
 
 #include "config.hpp"
 #include "files.hpp"
+#include "frontend.hpp"
 #include "main.hpp"
 #include "util.hpp"
 #include "variable.hpp"
@@ -261,34 +262,6 @@ static void term_data_set_fg(term_data *td, byte attr)
 
 
 /*
- * Free data used by a term
- */
-static void Term_nuke_gtk(void *data)
-{
-	term_data *td = (term_data *) data;
-
-	/* Free name */
-	if (td->name) free(td->name);
-
-	/* Forget it */
-	td->name = NULL;
-
-	/* Free font */
-	if (td->font) gdk_font_unref(td->font);
-
-	/* Forget it */
-	td->font = NULL;
-
-	/* Free backing store */
-	if (td->backing_store) gdk_pixmap_unref(td->backing_store);
-
-	/* Forget it too */
-	td->backing_store = NULL;
-
-}
-
-
-/*
  * Erase the whole term.
  */
 static void Term_clear_gtk(term_data *td)
@@ -347,81 +320,6 @@ static errr Term_wipe_gtk(term_data *td, int x, int y, int n)
 
 
 /*
- * Draw some textual characters.
- */
-static void Term_text_gtk(void *data, int x, int y, int n, byte a, const char *s)
-{
-	term_data *td = (term_data *) data;
-
-	/* Don't draw to hidden windows */
-	if (!td->shown)
-	{
-		return;
-	}
-
-	/* Paranoia */
-	g_assert(td->drawing_area->window != 0);
-
-	/* Set foreground colour */
-	term_data_set_fg(td, a);
-
-	/* Clear the line */
-	Term_wipe_gtk(td, x, y, n);
-
-	/* Draw the text to the window */
-	gdk_draw_text(
-	        TERM_DATA_DRAWABLE(td),
-	        td->font,
-	        td->gc,
-	        x * td->font_wid,
-	        td->font->ascent + y * td->font_hgt,
-	        s,
-	        n);
-
-	/* Copy image from backing store if present */
-	TERM_DATA_REFRESH(td, x, y, n, 1);
-}
-
-
-/*
- * Draw software cursor at (x, y)
- */
-static void Term_curs_gtk(void *data, int x, int y)
-{
-	term_data *td = (term_data *) data;
-	int cells = 1;
-
-
-	/* Don't draw to hidden windows */
-	if (!td->shown)
-	{
-		return;
-	}
-
-	/* Paranoia */
-	g_assert(td->drawing_area->window != 0);
-
-	/* Set foreground colour */
-	term_data_set_fg(td, TERM_YELLOW);
-
-	/* Draw the software cursor */
-	gdk_draw_rectangle(
-	        TERM_DATA_DRAWABLE(td),
-	        td->gc,
-	        false,
-	        x * td->font_wid,
-	        y * td->font_hgt,
-	        td->font_wid * cells - 1,
-	        td->font_hgt - 1);
-
-	/* Copy image from backing store if present */
-	TERM_DATA_REFRESH(td, x, y, cells, 1);
-}
-
-
-
-
-/*
  * Process an event, if there's none block when wait is set true,
  * return immediately otherwise.
  */
@@ -442,70 +340,165 @@ static void DrainEvents()
 }
 
 
-/*
- * Handle a "special request"
+
+/**
+ * GTK2 implementation of a UserInterface
  */
-static void Term_xtra_gtk(void *term_data_ctx, int n, int v)
-{
-	term_data *td = (term_data *) term_data_ctx;
+class Gtk2Frontend final : public Frontend {
 
-	/* Handle a subset of the legal requests */
-	switch (n)
+private:
+	term_data *m_term_data;
+
+public:
+	Gtk2Frontend(term_data *term_data)
+		: m_term_data(term_data)
 	{
-		/* Make a noise */
-	case TERM_XTRA_NOISE:
-		{
-			gdk_beep();
-			return;
-		}
+	}
 
-		/* Flush the output */
-	case TERM_XTRA_FRESH:
+	void init() final
+	{
+	}
+
+	void nuke() final
+	{
+		/* Free name */
+		if (m_term_data->name)
 		{
-			gdk_flush();
-			return;
+			free(m_term_data->name);
 		}
+		m_term_data->name = NULL;
 
-		/* Process random events */
-	case TERM_XTRA_BORED:
+		/* Free font */
+		if (m_term_data->font)
 		{
-			CheckEvent(false);
-			return;
+			gdk_font_unref(m_term_data->font);
 		}
+		m_term_data->font = NULL;
 
-		/* Process Events */
-	case TERM_XTRA_EVENT:
+		/* Free backing store */
+		if (m_term_data->backing_store)
 		{
-			CheckEvent(v);
-			return;
+			gdk_pixmap_unref(m_term_data->backing_store);
 		}
+		m_term_data->backing_store = NULL;
+	}
 
-		/* Flush the events */
-	case TERM_XTRA_FLUSH:
+	void process_event(bool wait) final
+	{
+		CheckEvent(wait);
+	}
+
+	bool soft_cursor() const final
+	{
+		return true;
+	}
+
+	bool icky_corner() const final
+	{
+		return false;
+	}
+
+	void flush_events() final
+	{
+		DrainEvents();
+	}
+
+	void process_queued_events() final
+	{
+		CheckEvent(false);
+	}
+
+	void clear() final
+	{
+		Term_clear_gtk(m_term_data);
+	}
+
+	void flush_output() final
+	{
+		gdk_flush();
+	}
+
+	void noise() final
+	{
+		gdk_beep();
+	}
+
+	void react() final
+	{
+		init_colours();
+	}
+
+	void activate_deactivate(bool resume) final
+	{
+		// No action necessary
+	};
+
+	void rename_main_window(std::string_view name_sv) final
+	{
+		gtk_window_set_title(GTK_WINDOW(data[0].window), std::string(angband_term_name[0]).c_str());
+	}
+
+	void draw_cursor(int x, int y) final
+	{
+		int cells = 1;
+
+		/* Don't draw to hidden windows */
+		if (!m_term_data->shown)
 		{
-			DrainEvents();
 			return;
 		}
 
-		/* Clear the screen */
-	case TERM_XTRA_CLEAR:
-		Term_clear_gtk(td);
-		return;
+		/* Paranoia */
+		g_assert(m_term_data->drawing_area->window != 0);
 
-		/* Rename main window */
-	case TERM_XTRA_RENAME_MAIN_WIN:
-		gtk_window_set_title(GTK_WINDOW(data[0].window), angband_term_name[0]);
-		return;
+		/* Set foreground colour */
+		term_data_set_fg(m_term_data, TERM_YELLOW);
+
+		/* Draw the software cursor */
+		gdk_draw_rectangle(
+			TERM_DATA_DRAWABLE(m_term_data),
+			m_term_data->gc,
+			false,
+			x * m_term_data->font_wid,
+			y * m_term_data->font_hgt,
+			m_term_data->font_wid * cells - 1,
+			m_term_data->font_hgt - 1);
+
+		/* Copy image from backing store if present */
+		TERM_DATA_REFRESH(m_term_data, x, y, cells, 1);
+	}
 
-		/* React to changes */
-	case TERM_XTRA_REACT:
+	void draw_text(int x, int y, int n, byte a, const char *s) final
+	{
+		/* Don't draw to hidden windows */
+		if (!m_term_data->shown)
 		{
-			init_colours();
 			return;
 		}
-	}
-}
 
+		/* Paranoia */
+		g_assert(m_term_data->drawing_area->window != 0);
+
+		/* Set foreground colour */
+		term_data_set_fg(m_term_data, a);
+
+		/* Clear the line */
+		Term_wipe_gtk(m_term_data, x, y, n);
+
+		/* Draw the text to the window */
+		gdk_draw_text(
+			TERM_DATA_DRAWABLE(m_term_data),
+			m_term_data->font,
+			m_term_data->gc,
+			x * m_term_data->font_wid,
+			m_term_data->font->ascent + y * m_term_data->font_hgt,
+			s,
+			n);
+
+		/* Copy image from backing store if present */
+		TERM_DATA_REFRESH(m_term_data, x, y, n, 1);
+	}
+};
 
 
 
@@ -1215,19 +1208,8 @@ static term *term_data_init(term_data *td, int i)
 	td->cols = 80;
 	td->rows = 24;
 
-	/* Hooks */
-	struct term_ui_hooks_t ui_hooks = {
-		NULL /* init */,
-		Term_nuke_gtk,
-		Term_xtra_gtk,
-		Term_curs_gtk,
-		Term_text_gtk,
-	};
-
 	/* Initialize the term */
-	td->term_ptr = term_init(td, td->cols, td->rows, 1024);
-	term_init_soft_cursor(td->term_ptr);
-	term_init_ui_hooks(td->term_ptr, ui_hooks);
+	td->term_ptr = term_init(td->cols, td->rows, 1024, std::make_shared<Gtk2Frontend>(td));
 
 	/* Store the name of the term */
 	assert(angband_term_name[i] != NULL);
diff --git a/src/main-x11.cc b/src/main-x11.cc
index 97e1b212..aacbf3a0 100644
--- a/src/main-x11.cc
+++ b/src/main-x11.cc
@@ -94,6 +94,7 @@
 
 #include "config.hpp"
 #include "defines.hpp"
+#include "frontend.hpp"
 #include "loadsave.hpp"
 #include "main.hpp"
 #include "util.hpp"
@@ -553,28 +554,27 @@ static errr Metadpy_new(const char *name)
 
 
 /*
- * Make a simple beep
+ * Set the name (in the title bar) of Infowin
  */
-static void Metadpy_do_beep()
+static void Infowin_set_name(std::string_view name_sv)
 {
-	/* Make a simple beep */
-	XBell(Metadpy->dpy, 100);
-}
+	char buf[128];
 
+	// Trim to the size of the buffer - 1 so that
+	// strncpy is guaranteed to NUL-terminate.
+	auto name = name_sv.substr(0, sizeof(buf) - 1);
 
+	// Copy
+	strncpy(buf, name.begin(), name.size());
 
-/*
- * Set the name (in the title bar) of Infowin
- */
-static void Infowin_set_name(const char *name)
-{
-	Status st;
-	XTextProperty tp;
-	char buf[128];
 	char *bp = buf;
-	strcpy(buf, name);
-	st = XStringListToTextProperty(&bp, 1, &tp);
-	if (st) XSetWMName(Metadpy->dpy, Infowin->win, &tp);
+
+	// Set
+	XTextProperty tp;
+	Status st = XStringListToTextProperty(&bp, 1, &tp);
+	if (st) {
+		XSetWMName(Metadpy->dpy, Infowin->win, &tp);
+	}
 }
 
 
@@ -1368,150 +1368,134 @@ static errr CheckEvent(term_data *old_td, bool wait)
 }
 
 
-/*
- * Handle "activation" of a term
+/**
+ * UserInterace for X11
  */
-static void Term_xtra_x11_level(term_data *td, int v)
-{
-	/* Handle "activate" */
-	if (v)
-	{
-		/* Activate the window */
-		Infowin_set(td->win);
-
-		/* Activate the font */
-		Infofnt_set(td->fnt);
-	}
-}
+class X11Frontend final : public Frontend {
 
+private:
+	term_data *m_term_data;
 
-/*
- * React to changes
- */
-static void Term_xtra_x11_react()
-{
-	int i;
-
-	if (Metadpy->color)
+public:
+	explicit X11Frontend(term_data *term_data)
+		: m_term_data(term_data)
 	{
-		/* Check the colors */
-		for (i = 0; i < 256; i++)
-		{
-			if ((color_table[i][0] != angband_color_table[i][0]) ||
-			                (color_table[i][1] != angband_color_table[i][1]) ||
-			                (color_table[i][2] != angband_color_table[i][2]) ||
-			                (color_table[i][3] != angband_color_table[i][3]))
-			{
-				Pixell pixel;
-
-				/* Save new values */
-				color_table[i][0] = angband_color_table[i][0];
-				color_table[i][1] = angband_color_table[i][1];
-				color_table[i][2] = angband_color_table[i][2];
-				color_table[i][3] = angband_color_table[i][3];
-
-				/* Create pixel */
-				pixel = create_pixel(Metadpy->dpy,
-				                     color_table[i][1],
-				                     color_table[i][2],
-				                     color_table[i][3]);
-
-				/* Change the foreground */
-				Infoclr_set(clr[i]);
-				Infoclr_change_fg(pixel);
-			}
-		}
 	}
-}
-
-
-/*
- * Handle a "special request"
- */
-static void Term_xtra_x11(void *data, int n, int v)
-{
-	term_data *td = (term_data*) data;
 
-	/* Handle a subset of the legal requests */
-	switch (n)
+	void init() final
 	{
-		/* Make a noise */
-	case TERM_XTRA_NOISE:
-		Metadpy_do_beep();
-		return;
+		// No action necessary
+	}
 
-		/* Flush the output XXX XXX */
-	case TERM_XTRA_FRESH:
-		XFlush(Metadpy->dpy);
-		return;
+	bool soft_cursor() const final
+	{
+		return true;
+	}
 
-		/* Process random events XXX */
-	case TERM_XTRA_BORED:
-		CheckEvent(td, false);
-		return;
+	bool icky_corner() const final
+	{
+		return false;
+	}
 
-		/* Process Events XXX */
-	case TERM_XTRA_EVENT:
-		CheckEvent(td, v);
-		return;
+	void nuke() final
+	{
+		// No action necessary
+	}
 
-		/* Flush the events XXX */
-	case TERM_XTRA_FLUSH:
-		while (!CheckEvent(td, false));
-		return;
+	void process_event(bool wait) final
+	{
+		CheckEvent(m_term_data, wait);
+	}
 
-		/* Handle change in the "level" */
-	case TERM_XTRA_LEVEL:
-		Term_xtra_x11_level(td, v);
-		return;
+	void flush_events() final
+	{
+		while (!CheckEvent(m_term_data, false))
+		{
+			// Keep flushing
+		}
+	}
 
-		/* Clear the screen */
-	case TERM_XTRA_CLEAR:
+	void clear() final
+	{
 		Infowin_wipe();
-		return;
-
-		/* React to changes */
-	case TERM_XTRA_REACT:
-		Term_xtra_x11_react();
-		return;
-
-		/* Rename main window */
-	case TERM_XTRA_RENAME_MAIN_WIN:
-		Infowin_set_name(angband_term_name[0]);
-		return;
 	}
-}
 
+	void flush_output() final
+	{
+		XFlush(Metadpy->dpy);
+	}
 
-/*
- * Draw the cursor as an inverted rectangle.
- *
- * Consider a rectangular outline like "main-mac.c".  XXX XXX
- */
-static void Term_curs_x11(void *data, int x, int y)
-{
-	/* Draw the cursor */
-	Infoclr_set(cursor_clr);
+	void noise() final
+	{
+		XBell(Metadpy->dpy, 100);
+	}
 
-	/* Hilite the cursor character */
-	Infofnt_text_non(x, y, " ", 1);
-}
+	void process_queued_events() final
+	{
+		CheckEvent(m_term_data, false);
+	}
 
+	void react() final
+	{
+		if (Metadpy->color)
+		{
+			/* Check the colors */
+			for (int i = 0; i < 256; i++)
+			{
+				if ((color_table[i][0] != angband_color_table[i][0]) ||
+						(color_table[i][1] != angband_color_table[i][1]) ||
+						(color_table[i][2] != angband_color_table[i][2]) ||
+						(color_table[i][3] != angband_color_table[i][3]))
+				{
+					Pixell pixel;
+
+					/* Save new values */
+					color_table[i][0] = angband_color_table[i][0];
+					color_table[i][1] = angband_color_table[i][1];
+					color_table[i][2] = angband_color_table[i][2];
+					color_table[i][3] = angband_color_table[i][3];
+
+					/* Create pixel */
+					pixel = create_pixel(Metadpy->dpy,
+							     color_table[i][1],
+							     color_table[i][2],
+							     color_table[i][3]);
+
+					/* Change the foreground */
+					Infoclr_set(clr[i]);
+					Infoclr_change_fg(pixel);
+				}
+			}
+		}
+	}
 
-/*
- * Draw some textual characters.
- */
-static void Term_text_x11(void *data, int x, int y, int n, byte a, const char *s)
-{
-	/* Draw the text */
-	Infoclr_set(clr[a]);
+	void activate_deactivate(bool resume) final
+	{
+		if (resume)
+		{
+			Infowin_set(m_term_data->win);
+			Infofnt_set(m_term_data->fnt);
+		}
 
-	/* Draw the text */
-	Infofnt_text_std(x, y, s, n);
-}
+	}
 
+	void rename_main_window(std::string_view sv) final
+	{
+		Infowin_set_name(sv);
+	}
 
+	void draw_cursor(int x, int y) final
+	{
+		Infoclr_set(cursor_clr);
+		Infofnt_text_non(x, y, " ", 1);
+	}
 
+	void draw_text(int x, int y, int n, byte a, const char *s) final
+	{
+		Infoclr_set(clr[a]);
+		Infofnt_text_std(x, y, s, n);
+	}
+};
 
 
 /*
@@ -1745,19 +1729,8 @@ static term *term_data_init(term_data *td, int i)
 	/* Move the window to requested location */
 	if ((x >= 0) && (y >= 0)) Infowin_impell(x, y);
 
-	/* Hooks */
-	struct term_ui_hooks_t ui_hooks = {
-		NULL /* init */,
-		NULL /* nuke */,
-		Term_xtra_x11,
-		Term_curs_x11,
-		Term_text_x11,
-	};
-
 	/* Initialize the term */
-	td->term_ptr = term_init(td, cols, rows, num);
-	term_init_soft_cursor(td->term_ptr);
-	term_init_ui_hooks(td->term_ptr, ui_hooks);
+	td->term_ptr = term_init(cols, rows, num, std::make_shared<X11Frontend>(td));
 
 	/* Activate (important) */
 	Term_activate(td->term_ptr);
diff --git a/src/modules.cc b/src/modules.cc
index fe5ff2e9..08c16a93 100644
--- a/src/modules.cc
+++ b/src/modules.cc
@@ -187,7 +187,7 @@ static void activate_module(int module_idx)
 	if (equals(game_module, "ToME"))
 	{
 		strnfmt(angband_term_name[0], 79, "T-Engine: %s", game_module);
-		Term_xtra(TERM_XTRA_RENAME_MAIN_WIN, 0);
+		Term_rename_main_win(angband_term_name[0]);
 	}
 }
 
diff --git a/src/z-term.cc b/src/z-term.cc
index ca658bb4..764997c3 100644
--- a/src/z-term.cc
+++ b/src/z-term.cc
@@ -11,6 +11,7 @@
 #include "z-term.hpp"
 
 #include "key_queue.hpp"
+#include "frontend.hpp"
 #include "tome/unique_handle.hpp"
 
 #include <cassert>
@@ -415,13 +416,9 @@ static errr push_result_to_errr(key_queue::push_result_t r)
 
 struct term
 {
-	void *data;
-
 	bool active_flag = false;
 	bool mapped_flag = false;
 	bool total_erase = true;
-	bool icky_corner = false;
-	bool soft_cursor = false;
 
 	key_queue m_key_queue;
 
@@ -438,24 +435,24 @@ struct term
 	std::unique_ptr<term_win> scr;
 	std::unique_ptr<term_win> mem;
 
-	init_hook_t *init_hook = nullptr;
-	nuke_hook_t *nuke_hook = nullptr;
-	xtra_hook_t *xtra_hook = nullptr;
-	curs_hook_t *curs_hook = nullptr;
-	text_hook_t *text_hook = nullptr;
+	std::shared_ptr<Frontend> m_frontend;
+	std::function<void ()> m_resize_hook;
 
-	resize_hook_t *resize_hook = nullptr;
+	bool icky_corner;
+	bool soft_cursor;
 
 	/**
 	 * Ctor
 	 */
-	term(int w, int h, int k, void *data_)
-		: data(data_)
-		, m_key_queue(k)
+	term(int w, int h, int k, std::shared_ptr<Frontend> user_interface)
+		: m_key_queue(k)
 		, wid(w)
 		, hgt(h)
 		, x1(h)
 		, x2(h)
+		, m_frontend(std::move(user_interface))
+		, icky_corner(m_frontend->icky_corner())
+		, soft_cursor(m_frontend->soft_cursor())
 	{
 		/* Allocate "displayed" */
 		old = std::make_unique<term_win>(w, h);
@@ -485,10 +482,7 @@ struct term
 		if (active_flag)
 		{
 			/* Call the "nuke" hook */
-			if (nuke_hook)
-			{
-				(*nuke_hook)(data);
-			}
+			m_frontend->nuke();
 
 			/* Remember */
 			active_flag = false;
@@ -498,31 +492,29 @@ struct term
 		}
 	}
 
-};
+	void text(int x, int y, int n, byte a, const char *s)
+	{
+		m_frontend->draw_text(x, y, n, a, s);
+	}
 
+	void curs(int x, int y)
+	{
+		m_frontend->draw_cursor(x, y);
+	}
 
+	void fresh()
+	{
+		m_frontend->flush_output();
+	}
 
-/*
- * The current "term"
- */
-term *Term = nullptr;
+};
 
-/*** External hooks ***/
 
 
 /*
- * Execute the "Term->xtra_hook" hook, if any.
+ * The current "term"
  */
-void Term_xtra(int n, int v)
-{
-	if (Term->xtra_hook)
-	{
-		(*Term->xtra_hook)(Term->data, n, v);
-	}
-}
-
-
-/*** Efficient routines ***/
+term *Term = nullptr;
 
 
 /*
@@ -609,25 +601,6 @@ static const byte ATTR_BLANK = TERM_WHITE;
 static const char CHAR_BLANK = ' ';
 
 /*
- * Call the text hook
- */
-static void do_text_hook(int x, int y, int n, byte a, const char *s)
-{
-	assert(Term->text_hook);
-	(*Term->text_hook)(Term->data, x, y, n, a, s);
-}
-
-/*
- * Call the curs hook
- */
-static void do_curs_hook(int x, int y)
-{
-	assert(Term->curs_hook);
-	(*Term->curs_hook)(Term->data, x, y);
-}
-
-
-/*
  * Flush a row of the current window (see "Term_fresh")
  *
  * Display text using "Term_text()" and "Term_wipe()"
@@ -674,7 +647,7 @@ static void Term_fresh_row_text(int y, int x1, int x2)
 			/* Flush */
 			if (fn)
 			{
-				do_text_hook(fx, y, fn, fa, &scr_cc[fx]);
+				Term->text(fx, y, fn, fa, &scr_cc[fx]);
 
 				/* Forget */
 				fn = 0;
@@ -695,7 +668,7 @@ static void Term_fresh_row_text(int y, int x1, int x2)
 			if (fn)
 			{
 				/* Draw the pending chars */
-				do_text_hook(fx, y, fn, fa, &scr_cc[fx]);
+				Term->text(fx, y, fn, fa, &scr_cc[fx]);
 
 				/* Forget */
 				fn = 0;
@@ -712,7 +685,7 @@ static void Term_fresh_row_text(int y, int x1, int x2)
 	/* Flush */
 	if (fn)
 	{
-		do_text_hook(fx, y, fn, fa, &scr_cc[fx]);
+		Term->text(fx, y, fn, fa, &scr_cc[fx]);
 	}
 }
 
@@ -838,7 +811,7 @@ void Term_fresh()
 		char nc = CHAR_BLANK;
 
 		/* Physically erase the entire window */
-		Term_xtra(TERM_XTRA_CLEAR, 0);
+		Term->m_frontend->clear();
 
 		/* Hack -- clear all "cursor" data */
 		old->cv = false;
@@ -893,7 +866,7 @@ void Term_fresh()
 			char oc = old_cc[tx];
 
 			/* Hack -- restore the actual character */
-			do_text_hook(tx, ty, 1, oa, &oc);
+			Term->text(tx, ty, 1, oa, &oc);
 		}
 	}
 
@@ -947,7 +920,7 @@ void Term_fresh()
 		if (!scr->cu && scr->cv)
 		{
 			/* Call the cursor display routine */
-			do_curs_hook(scr->cx, scr->cy);
+			Term->curs(scr->cx, scr->cy);
 		}
 	}
 
@@ -958,7 +931,7 @@ void Term_fresh()
 		if (scr->cu)
 		{
 			/* Paranoia -- Put the cursor NEAR where it belongs */
-			do_curs_hook(w - 1, scr->cy);
+			Term->curs(w - 1, scr->cy);
 
 			/* Make the cursor invisible */
 			/* Term_xtra(TERM_XTRA_SHAPE, 0); */
@@ -968,7 +941,7 @@ void Term_fresh()
 		else if (!scr->cv)
 		{
 			/* Paranoia -- Put the cursor where it belongs */
-			do_curs_hook(scr->cx, scr->cy);
+			Term->curs(scr->cx, scr->cy);
 
 			/* Make the cursor invisible */
 			/* Term_xtra(TERM_XTRA_SHAPE, 0); */
@@ -978,7 +951,7 @@ void Term_fresh()
 		else
 		{
 			/* Put the cursor where it belongs */
-			do_curs_hook(scr->cx, scr->cy);
+			Term->curs(scr->cx, scr->cy);
 		}
 	}
 
@@ -991,7 +964,7 @@ void Term_fresh()
 
 
 	/* Actually flush the output */
-	Term_xtra(TERM_XTRA_FRESH, 0);
+	Term->fresh();
 }
 
 
@@ -1353,7 +1326,7 @@ void Term_redraw_section(int x1, int y1, int x2, int y2)
 
 void Term_bell()
 {
-	Term_xtra(TERM_XTRA_NOISE, 0);
+	Term->m_frontend->noise();
 }
 
 /*** Access routines ***/
@@ -1554,7 +1527,7 @@ void Term_show_cursor()
 void Term_flush()
 {
 	/* Hack -- Flush all events */
-	Term_xtra(TERM_XTRA_FLUSH, 0);
+	Term->m_frontend->flush_events();
 
 	/* Forget all keypresses */
 	Term->m_key_queue.clear();
@@ -1606,7 +1579,7 @@ errr Term_inkey(char *ch, bool wait, bool take)
 	(*ch) = '\0';
 
 	/* Process queued UI events */
-	Term_xtra(TERM_XTRA_BORED, 0);
+	Term->m_frontend->process_queued_events();
 
 	/* Wait */
 	if (wait)
@@ -1615,7 +1588,7 @@ errr Term_inkey(char *ch, bool wait, bool take)
 		while (key_queue.empty())
 		{
 			/* Process events (wait for one) */
-			Term_xtra(TERM_XTRA_EVENT, true);
+			Term->m_frontend->process_event(true);
 		}
 	}
 
@@ -1626,7 +1599,7 @@ errr Term_inkey(char *ch, bool wait, bool take)
 		if (key_queue.empty())
 		{
 			/* Process events (do not wait) */
-			Term_xtra(TERM_XTRA_EVENT, false);
+			Term->m_frontend->process_event(false);
 		}
 	}
 
@@ -1837,9 +1810,9 @@ void Term_resize(int w, int h)
 	Term->y2 = h - 1;
 
 	/* Execute the "resize_hook" hook, if available */
-	if (Term->resize_hook)
+	if (Term->m_resize_hook)
 	{
-		Term->resize_hook();
+		Term->m_resize_hook();
 	}
 }
 
@@ -1863,16 +1836,15 @@ void Term_activate(term *t)
 	}
 
 	/* Deactivate the old Term */
-	if (Term) Term_xtra(TERM_XTRA_LEVEL, 0);
+	if (Term)
+	{
+		Term->m_frontend->activate_deactivate(false);
+	}
 
 	/* Hack -- Call the special "init" hook */
 	if (t && !t->active_flag)
 	{
-		/* Call the "init" hook */
-		if (t->init_hook)
-		{
-			(*t->init_hook)(t->data);
-		}
+		t->m_frontend->init();
 
 		/* Remember */
 		t->active_flag = true;
@@ -1885,13 +1857,16 @@ void Term_activate(term *t)
 	Term = t;
 
 	/* Activate the new Term */
-	if (Term) Term_xtra(TERM_XTRA_LEVEL, 1);
+	if (Term)
+	{
+		Term->m_frontend->activate_deactivate(true);
+	}
 }
 
 
 void Term_xtra_react()
 {
-	Term_xtra(TERM_XTRA_REACT, 0);
+	Term->m_frontend->react();
 }
 
 /**
@@ -1912,12 +1887,9 @@ void Term_unmapped()
 }
 
 
-/*
- * Nuke a term
- */
-void term_nuke(term *t)
+void Term_rename_main_win(std::string_view name)
 {
-	delete t;
+	Term->m_frontend->rename_main_window(name);
 }
 
 
@@ -1927,31 +1899,23 @@ void term_nuke(term *t)
  * By default, the cursor starts out "invisible"
  * By default, we "erase" using "black spaces"
  */
-term *term_init(void *data, int w, int h, int k)
-{
-	return new term(w, h, k, data);
-}
-
-void term_init_icky_corner(term *t)
-{
-	t->icky_corner = true;
-}
-
-void term_init_soft_cursor(term *t)
+term *term_init(int w, int h, int k, std::shared_ptr<Frontend> user_interface)
 {
-	t->soft_cursor = true;
+	return new term(w, h, k, user_interface);
 }
 
-void term_init_ui_hooks(term *t, term_ui_hooks_t hooks)
+/*
+ * Nuke a term
+ */
+void term_nuke(term *t)
 {
-	t->init_hook = hooks.init_hook;
-	t->nuke_hook = hooks.nuke_hook;
-	t->xtra_hook = hooks.xtra_hook;
-	t->curs_hook = hooks.curs_hook;
-	t->text_hook = hooks.text_hook;
+	delete t;
 }
 
-void term_set_resize_hook(term *t, resize_hook_t *hook)
+/**
+ * Set the function to call when terminal is resized.
+ */
+void term_set_resize_hook(term *t, std::function<void ()> f)
 {
-	t->resize_hook = hook;
+	t->m_resize_hook = f;
 }
diff --git a/src/z-term.hpp b/src/z-term.hpp
index 83c903cc..24077c16 100644
--- a/src/z-term.hpp
+++ b/src/z-term.hpp
@@ -9,8 +9,11 @@
 #pragma once
 
 #include "h-basic.hpp"
+#include "frontend_fwd.hpp"
 
 #include <functional>
+#include <memory>
+#include <string_view>
 
 typedef struct term_win term_win;
 
@@ -20,38 +23,6 @@ typedef struct term term;
 
 struct term; // Opaque
 
-/*
- * UI hooks
- */
-
-typedef void(init_hook_t)(void *data);
-typedef void(nuke_hook_t)(void *data);
-typedef void(xtra_hook_t)(void *data, int n, int v);
-typedef void(curs_hook_t)(void *data, int x, int y);
-typedef void(text_hook_t)(void *data, int x, int y, int n, byte a, const char *s);
-
-typedef struct term_ui_hooks_t term_ui_hooks_t;
-
-struct term_ui_hooks_t {
-
-	init_hook_t *init_hook;
-
-	nuke_hook_t *nuke_hook;
-
-	xtra_hook_t *xtra_hook;
-
-	curs_hook_t *curs_hook;
-
-	text_hook_t *text_hook;
-
-};
-
-/*
- * Resize hook type
- */
-typedef void(resize_hook_t)();
-
-
 /*** Color constants ***/
 
 
@@ -80,42 +51,12 @@ typedef void(resize_hook_t)();
 
 
 
-/**** Available Constants ****/
-
-
-/*
- * Definitions for the "actions" of "Term_xtra()"
- *
- * These values may be used as the first parameter of "Term_xtra()",
- * with the second parameter depending on the "action" itself.  Many
- * of the actions shown below are optional on at least one platform.
- *
- * The "TERM_XTRA_EVENT" action uses "v" to "wait" for an event
- * The "TERM_XTRA_SHAPE" action uses "v" to "show" the cursor
- * The "TERM_XTRA_ALIVE" action uses "v" to "activate" (or "close")
- * The "TERM_XTRA_LEVEL" action uses "v" to "resume" (or "suspend")
- *
- * The other actions do not need a "v" code, so "zero" is used.
- */
-#define TERM_XTRA_EVENT	1	/* Process some pending events */
-#define TERM_XTRA_FLUSH 2	/* Flush all pending events */
-#define TERM_XTRA_CLEAR 3	/* Clear the entire window */
-#define TERM_XTRA_FRESH 6	/* Flush all rows (optional) */
-#define TERM_XTRA_NOISE 7	/* Make a noise (optional) */
-#define TERM_XTRA_BORED 9	/* Handle stuff when bored (optional) */
-#define TERM_XTRA_REACT 10	/* React to global changes (optional) */
-#define TERM_XTRA_LEVEL 12	/* Change the "soft" level (optional) */
-#define TERM_XTRA_RENAME_MAIN_WIN 16 /* Rename the main game window */
-
-
 /**** Available Variables ****/
 
 extern term *Term;
 
 /**** Available Functions ****/
 
-void Term_xtra(int n, int v);
-
 void Term_queue_char(int x, int y, byte a, char c);
 
 void Term_fresh();
@@ -160,10 +101,8 @@ void Term_xtra_react();
 
 void Term_mapped();
 void Term_unmapped();
+void Term_rename_main_win(std::string_view);
 
+term *term_init(int w, int h, int k, std::shared_ptr<Frontend> user_interface);
 void term_nuke(term *t);
-term *term_init(void *data, int w, int h, int k);
-void term_init_icky_corner(term *t);
-void term_init_soft_cursor(term *t);
-void term_init_ui_hooks(term *t, term_ui_hooks_t hooks);
-void term_set_resize_hook(term *t, resize_hook_t *hook);
+void term_set_resize_hook(term *t, std::function<void ()> f);