xruler

commit 5bee511bdc41bb290500059d6488ee4492b5f51b
parent 4490bedd1d309132e58f37c9fc0d3b4f5c03b520
Author: Matthias Balk <mbalk@mbalk.de>
Date:   Tue,  5 Nov 2019 19:01:50 +0100

print mouse coordinates in window (instead of stdout)

Diffstat:
M
xruler.c
 | 
78
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--

1 file changed, 76 insertions(+), 2 deletions(-)
diff --git a/xruler.c b/xruler.c
@@ -69,6 +69,79 @@ static void set_crosshair_cursor(
 }
 
 
+static xcb_gc_t get_gc_font(
+    xcb_connection_t *c,
+    xcb_screen_t     *screen,
+    xcb_window_t      window,
+    const char       *font_name)
+{
+  xcb_font_t font = xcb_generate_id(c);
+  xcb_void_cookie_t cookie_font =
+      xcb_open_font_checked(c, font, strlen(font_name), font_name);
+
+  xcb_generic_error_t *error;
+  error = xcb_request_check(c, cookie_font);
+  if (error) {
+    fprintf(stderr, "ERROR: can't open font : %d\n", error->error_code);
+    xcb_disconnect(c);
+    return -1;
+  }
+
+  xcb_gcontext_t gc = xcb_generate_id(c);
+  uint32_t mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT;
+  uint32_t value_list[] = {screen->black_pixel, screen->white_pixel, font};
+  xcb_void_cookie_t cookie_gc =
+      xcb_create_gc_checked(c, gc, window, mask, value_list);
+
+  error = xcb_request_check(c, cookie_gc);
+  if (error) {
+    fprintf(stderr, "ERROR: can't create gc : %d\n", error->error_code);
+    xcb_disconnect(c);
+    exit(-1);
+  }
+
+  cookie_font = xcb_close_font_checked(c, font);
+  error = xcb_request_check(c, cookie_font);
+  if (error) {
+    fprintf(stderr, "ERROR: can't close font : %d\n", error->error_code);
+    xcb_disconnect(c);
+    exit(-1);
+  }
+
+  return gc;
+}
+
+
+static void draw_text(
+    xcb_connection_t *c,
+    xcb_screen_t     *screen,
+    xcb_window_t      window,
+    int16_t           x,
+    int16_t           y,
+    const char       *label)
+{
+  xcb_gcontext_t gc = get_gc_font(c, screen, window, "8x13");
+  xcb_void_cookie_t cookie_text =
+      xcb_image_text_8_checked(c, strlen(label), window, gc, x, y, label);
+
+  xcb_generic_error_t *error;
+  error = xcb_request_check(c, cookie_text);
+  if (error) {
+    fprintf(stderr, "ERROR: can't paste text : %d\n", error->error_code);
+    xcb_disconnect(c);
+    exit(-1);
+  }
+
+  xcb_void_cookie_t cookie_gc = xcb_free_gc(c, gc);
+  error = xcb_request_check(c, cookie_gc);
+  if (error) {
+    fprintf(stderr, "ERROR: can't free gc : %d\n", error->error_code);
+    xcb_disconnect(c);
+    exit(-1);
+  }
+}
+
+
 int main (int argc, char** argv)
 {
   /* Open the connection to the X server */
@@ -156,8 +229,9 @@ int main (int argc, char** argv)
       case XCB_MOTION_NOTIFY:
       {
         xcb_motion_notify_event_t* motion = (xcb_motion_notify_event_t*) event;
-        printf("Mouse moved in window %u, at coordinates (%u,%u)\n",
-                motion->event, motion->event_x, motion->event_y );
+        char buf[16];
+        snprintf(buf, 16, "%04u,%04u", motion->event_x, motion->event_y);
+        draw_text(connection, screen, window, 5, height - 5, buf);
         break;
       }