AnimationPlayer FPS mode fixes

(cherry picked from commit e3b7f9e1ca34e270eb7a7c2ec82b7f7354bb74e5)

editor/animation_track_editor.cpp

@@ -1022,8 +1022,14 @@ void AnimationTimelineEdit::update_values() {
 	editing = true;
 	if (use_fps && animation->get_step() > 0) {
 		length->set_value(animation->get_length() / animation->get_step());
+		length->set_step(1);
+		length->set_tooltip(TTR("Animation length (frames)"));
+		time_icon->set_tooltip(TTR("Animation length (frames)"));
 	} else {
 		length->set_value(animation->get_length());
+		length->set_step(0.01);
+		length->set_tooltip(TTR("Animation length (seconds)"));
+		time_icon->set_tooltip(TTR("Animation length (seconds)"));
 	}
 	loop->set_pressed(animation->has_loop());
 	editing = false;
@@ -1168,7 +1174,7 @@ AnimationTimelineEdit::AnimationTimelineEdit() {
 	len_hb->add_child(expander);
 	time_icon = memnew(TextureRect);
 	time_icon->set_v_size_flags(SIZE_SHRINK_CENTER);
-	time_icon->set_tooltip(TTR("Animation Length Time (seconds)"));
+	time_icon->set_tooltip(TTR("Animation length (seconds)"));
 	len_hb->add_child(time_icon);
 	length = memnew(EditorSpinSlider);
 	length->set_min(0.001);
@@ -1177,7 +1183,7 @@ AnimationTimelineEdit::AnimationTimelineEdit() {
 	length->set_allow_greater(true);
 	length->set_custom_minimum_size(Vector2(70 * EDSCALE, 0));
 	length->set_hide_slider(true);
-	length->set_tooltip(TTR("Animation Length Time (seconds)"));
+	length->set_tooltip(TTR("Animation length (seconds)"));
 	length->connect("value_changed", this, "_anim_length_changed");
 	len_hb->add_child(length);
 	loop = memnew(ToolButton);
@@ -3857,7 +3863,7 @@ void AnimationTrackEditor::_insert_key_from_track(float p_ofs, int p_track) {
 	ERR_FAIL_INDEX(p_track, animation->get_track_count());
 
 	if (snap->is_pressed() && step->get_value() != 0) {
-		p_ofs = Math::stepify(p_ofs, step->get_value());
+		p_ofs = snap_time(p_ofs);
 	}
 	while (animation->track_find_key(p_track, p_ofs, true) != -1) { //make sure insertion point is valid
 		p_ofs += 0.001;
@@ -4889,7 +4895,14 @@ void AnimationTrackEditor::_selection_changed() {
 float AnimationTrackEditor::snap_time(float p_value) {
 
 	if (snap->is_pressed()) {
-		p_value = Math::stepify(p_value, step->get_value());
+
+		double snap_increment;
+		if (timeline->is_using_fps() && step->get_value() > 0)
+			snap_increment = 1.0 / step->get_value();
+		else
+			snap_increment = step->get_value();
+
+		p_value = Math::stepify(p_value, snap_increment);
 	}
 
 	return p_value;