Display freelook speed and zoom in units in the 3D editor viewport

Now that the 3D editor grid is infinite and adjusts its step automatically,
this helps people get a better sense of scale when moving around in the
3D viewport.

This also fixes the indicator bar drawing on hiDPI displays.

(cherry picked from commit eaae50fe4ae4585fa5af8ef63c2862153ceb29f5)

editor/plugins/spatial_editor_plugin.cpp

@@ -2574,15 +2574,14 @@ void SpatialEditorViewport::_notification(int p_what) {
 	}
 }
 
-static void draw_indicator_bar(Control &surface, real_t fill, Ref<Texture> icon) {
-
+static void draw_indicator_bar(Control &surface, real_t fill, const Ref<Texture> icon, const Ref<Font> font, const String &text) {
 	// Adjust bar size from control height
-	Vector2 surface_size = surface.get_size();
-	real_t h = surface_size.y / 2.0;
-	real_t y = (surface_size.y - h) / 2.0;
+	const Vector2 surface_size = surface.get_size();
+	const real_t h = surface_size.y / 2.0;
+	const real_t y = (surface_size.y - h) / 2.0;
 
-	Rect2 r(10, y, 6, h);
-	real_t sy = r.size.y * fill;
+	const Rect2 r(10 * EDSCALE, y, 6 * EDSCALE, h);
+	const real_t sy = r.size.y * fill;
 
 	// Note: because this bar appears over the viewport, it has to stay readable for any background color
 	// Draw both neutral dark and bright colors to account this
@@ -2590,9 +2589,12 @@ static void draw_indicator_bar(Control &surface, real_t fill, Ref<Texture> icon)
 	surface.draw_rect(Rect2(r.position.x, r.position.y + r.size.y - sy, r.size.x, sy), Color(1, 1, 1, 0.6));
 	surface.draw_rect(r.grow(1), Color(0, 0, 0, 0.7), false, Math::round(EDSCALE));
 
-	Vector2 icon_size = icon->get_size();
-	Vector2 icon_pos = Vector2(r.position.x - (icon_size.x - r.size.x) / 2, r.position.y + r.size.y + 2);
+	const Vector2 icon_size = icon->get_size();
+	const Vector2 icon_pos = Vector2(r.position.x - (icon_size.x - r.size.x) / 2, r.position.y + r.size.y + 2 * EDSCALE);
 	surface.draw_texture(icon, icon_pos);
+
+	// Draw text below the bar (for speed/zoom information).
+	surface.draw_string(font, Vector2(icon_pos.x, icon_pos.y + icon_size.y + 16 * EDSCALE), text);
 }
 
 void SpatialEditorViewport::_draw() {
@@ -2696,7 +2698,14 @@ void SpatialEditorViewport::_draw() {
 					if (logscale_t < 0.25)
 						logscale_t = 0.25 * Math::exp(4.0 * logscale_t - 1.0);
 
-					draw_indicator_bar(*surface, 1.0 - logscale_t, get_icon("ViewportSpeed", "EditorIcons"));
+					// Display the freelook speed to help the user get a better sense of scale.
+					const int precision = freelook_speed < 1.0 ? 2 : 1;
+					draw_indicator_bar(
+							*surface,
+							1.0 - logscale_t,
+							get_icon("ViewportSpeed", "EditorIcons"),
+							get_font("font", "Label"),
+							vformat("%s u/s", String::num(freelook_speed).pad_decimals(precision)));
 				}
 
 			} else {
@@ -2714,7 +2723,14 @@ void SpatialEditorViewport::_draw() {
 					if (logscale_t < 0.25)
 						logscale_t = 0.25 * Math::exp(4.0 * logscale_t - 1.0);
 
-					draw_indicator_bar(*surface, logscale_t, get_icon("ViewportZoom", "EditorIcons"));
+					// Display the zoom center distance to help the user get a better sense of scale.
+					const int precision = cursor.distance < 1.0 ? 2 : 1;
+					draw_indicator_bar(
+							*surface,
+							logscale_t,
+							get_icon("ViewportZoom", "EditorIcons"),
+							get_font("font", "Label"),
+							vformat("%s u", String::num(cursor.distance).pad_decimals(precision)));
 				}
 			}
 		}