Display invalid value keys in AnimationTrackEdit

Godot 2.1 and 3.0 had this feature but it was lost in the rewrite
of the animation editor in 3.1.
Drop unused KeyValid icon, since all valid keys now have a custom
type icon.

(cherry picked from commit b3d772ed837c57d590c064f9de4e2ea89eb55001)

editor/animation_track_editor.cpp

@@ -1205,7 +1205,9 @@ AnimationTimelineEdit::AnimationTimelineEdit() {
 ////////////////////////////////////
 
 void AnimationTrackEdit::_notification(int p_what) {
+
 	if (p_what == NOTIFICATION_DRAW) {
+
 		if (animation.is_null())
 			return;
 		ERR_FAIL_INDEX(track, animation->get_track_count());
@@ -1241,20 +1243,15 @@ void AnimationTrackEdit::_notification(int p_what) {
 			int ofs = in_group ? check->get_width() : 0; //not the best reference for margin but..
 
 			check_rect = Rect2(Point2(ofs, int(get_size().height - check->get_height()) / 2), check->get_size());
-
 			draw_texture(check, check_rect.position);
-
 			ofs += check->get_width() + hsep;
 
 			Ref<Texture> type_icon = type_icons[animation->track_get_type(track)];
-
 			draw_texture(type_icon, Point2(ofs, int(get_size().height - type_icon->get_height()) / 2));
 			ofs += type_icon->get_width() + hsep;
 
 			NodePath path = animation->track_get_path(track);
-
 			Node *node = NULL;
-
 			if (root && root->has_node(path)) {
 				node = root->get_node(path);
 			}
@@ -1319,12 +1316,11 @@ void AnimationTrackEdit::_notification(int p_what) {
 			draw_line(Point2(limit, 0), Point2(limit, get_size().height), linecolor, Math::round(EDSCALE));
 		}
 
-		// KEYFAMES //
+		// KEYFRAMES //
 
 		draw_bg(limit, get_size().width - timeline->get_buttons_width());
 
 		{
-
 			float scale = timeline->get_zoom_scale();
 			int limit_end = get_size().width - timeline->get_buttons_width();
 
@@ -1353,6 +1349,7 @@ void AnimationTrackEdit::_notification(int p_what) {
 		draw_fg(limit, get_size().width - timeline->get_buttons_width());
 
 		// BUTTONS //
+
 		{
 
 			Ref<Texture> wrap_icon[2] = {
@@ -1577,7 +1574,18 @@ void AnimationTrackEdit::draw_key(int p_index, float p_pixels_sec, int p_x, bool
 	if (p_x < p_clip_left || p_x > p_clip_right)
 		return;
 
-	Vector2 ofs(p_x - type_icon->get_width() / 2, int(get_size().height - type_icon->get_height()) / 2);
+	Ref<Texture> icon_to_draw = p_selected ? selected_icon : type_icon;
+
+	// Override type icon for invalid value keys, unless selected.
+	if (!p_selected && animation->track_get_type(track) == Animation::TYPE_VALUE) {
+		const Variant &v = animation->track_get_key_value(track, p_index);
+		Variant::Type valid_type = Variant::NIL;
+		if (!_is_value_key_valid(v, valid_type)) {
+			icon_to_draw = get_icon("KeyInvalid", "EditorIcons");
+		}
+	}
+
+	Vector2 ofs(p_x - icon_to_draw->get_width() / 2, int(get_size().height - icon_to_draw->get_height()) / 2);
 
 	if (animation->track_get_type(track) == Animation::TYPE_METHOD) {
 		Ref<Font> font = get_font("font", "Label");
@@ -1601,16 +1609,13 @@ void AnimationTrackEdit::draw_key(int p_index, float p_pixels_sec, int p_x, bool
 		}
 		text += ")";
 
-		int limit = MAX(0, p_clip_right - p_x - type_icon->get_width());
+		int limit = MAX(0, p_clip_right - p_x - icon_to_draw->get_width());
 		if (limit > 0) {
-			draw_string(font, Vector2(p_x + type_icon->get_width(), int(get_size().height - font->get_height()) / 2 + font->get_ascent()), text, color, limit);
+			draw_string(font, Vector2(p_x + icon_to_draw->get_width(), int(get_size().height - font->get_height()) / 2 + font->get_ascent()), text, color, limit);
 		}
 	}
-	if (p_selected) {
-		draw_texture(selected_icon, ofs);
-	} else {
-		draw_texture(type_icon, ofs);
-	}
+
+	draw_texture(icon_to_draw, ofs);
 }
 
 //helper
@@ -1775,6 +1780,27 @@ void AnimationTrackEdit::_path_entered(const String &p_text) {
 	undo_redo->commit_action();
 }
 
+bool AnimationTrackEdit::_is_value_key_valid(const Variant &p_key_value, Variant::Type &r_valid_type) const {
+
+	RES res;
+	Vector<StringName> leftover_path;
+	Node *node = root->get_node_and_resource(animation->track_get_path(track), res, leftover_path);
+
+	Object *obj = NULL;
+	if (res.is_valid()) {
+		obj = res.ptr();
+	} else if (node) {
+		obj = node;
+	}
+
+	bool prop_exists = false;
+	if (obj) {
+		r_valid_type = obj->get_static_property_type_indexed(leftover_path, &prop_exists);
+	}
+
+	return (!prop_exists || Variant::can_convert(p_key_value.get_type(), r_valid_type));
+}
+
 String AnimationTrackEdit::get_tooltip(const Point2 &p_pos) const {
 
 	if (check_rect.has_point(p_pos)) {
@@ -1845,29 +1871,10 @@ String AnimationTrackEdit::get_tooltip(const Point2 &p_pos) const {
 				} break;
 				case Animation::TYPE_VALUE: {
 
-					Variant v = animation->track_get_key_value(track, key_idx);
-					//text+="value: "+String(v)+"\n";
-
-					bool prop_exists = false;
-					Variant::Type valid_type = Variant::NIL;
-					Object *obj = NULL;
-
-					RES res;
-					Vector<StringName> leftover_path;
-					Node *node = root->get_node_and_resource(animation->track_get_path(track), res, leftover_path);
-
-					if (res.is_valid()) {
-						obj = res.ptr();
-					} else if (node) {
-						obj = node;
-					}
-
-					if (obj) {
-						valid_type = obj->get_static_property_type_indexed(leftover_path, &prop_exists);
-					}
-
+					const Variant &v = animation->track_get_key_value(track, key_idx);
 					text += "Type: " + Variant::get_type_name(v.get_type()) + "\n";
-					if (prop_exists && !Variant::can_convert(v.get_type(), valid_type)) {
+					Variant::Type valid_type = Variant::NIL;
+					if (!_is_value_key_valid(v, valid_type)) {
 						text += "Value: " + String(v) + "  (Invalid, expected type: " + Variant::get_type_name(valid_type) + ")\n";
 					} else {
 						text += "Value: " + String(v) + "\n";

editor/animation_track_editor.h

@@ -31,6 +31,11 @@
 #ifndef ANIMATION_TRACK_EDITOR_H
 #define ANIMATION_TRACK_EDITOR_H
 
+#include "editor/editor_data.h"
+#include "editor/editor_spin_slider.h"
+#include "editor/property_editor.h"
+#include "editor/property_selector.h"
+#include "scene/animation/animation_cache.h"
 #include "scene/gui/control.h"
 #include "scene/gui/file_dialog.h"
 #include "scene/gui/menu_button.h"
@@ -40,12 +45,6 @@
 #include "scene/gui/tab_container.h"
 #include "scene/gui/texture_rect.h"
 #include "scene/gui/tool_button.h"
-
-#include "editor/property_selector.h"
-#include "editor_data.h"
-#include "editor_spin_slider.h"
-#include "property_editor.h"
-#include "scene/animation/animation_cache.h"
 #include "scene/resources/animation.h"
 #include "scene_tree_editor.h"
 
@@ -175,8 +174,9 @@ class AnimationTrackEdit : public Control {
 
 	void _path_entered(const String &p_text);
 	void _play_position_draw();
-	mutable int dropping_at;
+	bool _is_value_key_valid(const Variant &p_key_value, Variant::Type &r_valid_type) const;
 
+	mutable int dropping_at;
 	float insert_at_pos;
 	bool moving_selection_attempt;
 	int select_single_attempt;

editor/icons/icon_key_valid.svg

@@ -1,5 +0,0 @@
-<svg width="8" height="8" version="1.1" viewBox="0 0 8 8" xmlns="http://www.w3.org/2000/svg">
-<g transform="translate(0 -1044.4)">
-<rect transform="rotate(-45)" x="-741.53" y="741.08" width="6.1027" height="6.1027" ry=".76286" fill="#fff"/>
-</g>
-</svg>