Add a Frames option to the Timer node.

doc/classes/Timer.xml

@@ -12,7 +12,7 @@
 		    print("Time to attack!")
 		[/codeblock]
 		[b]Note:[/b] To create a one-shot timer without instantiating a node, use [method SceneTree.create_timer].
-		[b]Note:[/b] Timers are affected by [member Engine.time_scale]. The higher the time scale, the sooner timers will end. How often a timer processes may depend on the framerate or [member Engine.physics_ticks_per_second].
+		[b]Note:[/b] Timers in Time mode are affected by [member Engine.time_scale]. The higher the time scale, the sooner timers will end. How often a timer processes may depend on the framerate or [member Engine.physics_ticks_per_second].
 	</description>
 	<tutorials>
 		<link title="2D Dodge The Creeps Demo">https://godotengine.org/asset-library/asset/2712</link>
@@ -53,13 +53,17 @@
 		<member name="process_callback" type="int" setter="set_timer_process_callback" getter="get_timer_process_callback" enum="Timer.TimerProcessCallback" default="1">
 			Specifies when the timer is updated during the main loop (see [enum TimerProcessCallback]).
 		</member>
+		<member name="process_type" type="int" setter="set_timer_process_type" getter="get_timer_process_type" enum="Timer.TimerProcessType" default="0">
+			Specifies which units the timer uses to count. (see [enum TimerProcessType]).
+		</member>
 		<member name="time_left" type="float" setter="" getter="get_time_left">
 			The timer's remaining time in seconds. This is always [code]0[/code] if the timer is stopped.
 			[b]Note:[/b] This property is read-only and cannot be modified. It is based on [member wait_time].
 		</member>
 		<member name="wait_time" type="float" setter="set_wait_time" getter="get_wait_time" default="1.0">
-			The time required for the timer to end, in seconds. This property can also be set every time [method start] is called.
-			[b]Note:[/b] Timers can only process once per physics or process frame (depending on the [member process_callback]). An unstable framerate may cause the timer to end inconsistently, which is especially noticeable if the wait time is lower than roughly [code]0.05[/code] seconds. For very short timers, it is recommended to write your own code instead of using a [Timer] node. Timers are also affected by [member Engine.time_scale].
+			The time required for the timer to end, in seconds or frames. This property can also be set every time [method start] is called.
+			Time mode uses floats while Frame mode only accepts and returns non-fractional numbers.
+			[b]Note:[/b] Timers can only process once per physics or process frame (depending on the [member process_callback]). In Time mode, an unstable framerate may cause the timer to end inconsistently, which is especially noticeable if the wait time is lower than roughly [code]0.05[/code] seconds. For very short timers, it is recommended to write your own code instead of using a [Timer] node. Timers are also affected by [member Engine.time_scale].
 		</member>
 	</members>
 	<signals>
@@ -76,5 +80,11 @@
 		<constant name="TIMER_PROCESS_IDLE" value="1" enum="TimerProcessCallback">
 			Update the timer every process (rendered) frame (see [constant Node.NOTIFICATION_INTERNAL_PROCESS]).
 		</constant>
+		<constant name="TIMER_PROCESS_TYPE_TIME" value="0" enum="TimerProcessType">
+			Timer works with seconds. In this mode the timer is affected by [member Engine.time_scale].
+		</constant>
+		<constant name="TIMER_PROCESS_TYPE_FRAMES" value="1" enum="TimerProcessType">
+			Timer works with frames. Speed depends on the framerate. Accepts non-fractional values only.
+		</constant>
 	</constants>
 </class>

scene/main/timer.cpp

@@ -48,7 +48,15 @@ void Timer::_notification(int p_what) {
 			if (!processing || timer_process_callback == TIMER_PROCESS_PHYSICS || !is_processing_internal()) {
 				return;
 			}
-			time_left -= get_process_delta_time();
+
+			switch (timer_process_type) {
+				case TIMER_PROCESS_TYPE_TIME: {
+					time_left -= get_process_delta_time();
+				}; break;
+				case TIMER_PROCESS_TYPE_FRAMES: {
+					time_left -= 1;
+				}; break;
+			}
 
 			if (time_left < 0) {
 				if (!one_shot) {
@@ -60,12 +68,19 @@ void Timer::_notification(int p_what) {
 				emit_signal(SNAME("timeout"));
 			}
 		} break;
-
 		case NOTIFICATION_INTERNAL_PHYSICS_PROCESS: {
 			if (!processing || timer_process_callback == TIMER_PROCESS_IDLE || !is_physics_processing_internal()) {
 				return;
 			}
-			time_left -= get_physics_process_delta_time();
+
+			switch (timer_process_type) {
+				case TIMER_PROCESS_TYPE_TIME: {
+					time_left -= get_physics_process_delta_time();
+				}; break;
+				case TIMER_PROCESS_TYPE_FRAMES: {
+					time_left -= 1;
+				}; break;
+			}
 
 			if (time_left < 0) {
 				if (!one_shot) {
@@ -81,7 +96,12 @@ void Timer::_notification(int p_what) {
 
 void Timer::set_wait_time(double p_time) {
 	ERR_FAIL_COND_MSG(p_time <= 0, "Time should be greater than zero.");
-	wait_time = p_time;
+	if (timer_process_type == TIMER_PROCESS_TYPE_FRAMES) {
+		ERR_FAIL_COND_MSG(p_time != (int)p_time, "Frame mode only accepts non-fractional values. (Frames will be rounded.)");
+		wait_time = (int)p_time;
+	} else {
+		wait_time = p_time;
+	}
 	update_configuration_warnings();
 }
 
@@ -152,13 +172,13 @@ void Timer::set_timer_process_callback(TimerProcessCallback p_callback) {
 			if (is_physics_processing_internal()) {
 				set_physics_process_internal(false);
 				set_process_internal(true);
-			}
+			};
 			break;
 		case TIMER_PROCESS_IDLE:
 			if (is_processing_internal()) {
 				set_process_internal(false);
 				set_physics_process_internal(true);
-			}
+			};
 			break;
 	}
 	timer_process_callback = p_callback;
@@ -168,6 +188,26 @@ Timer::TimerProcessCallback Timer::get_timer_process_callback() const {
 	return timer_process_callback;
 }
 
+void Timer::set_timer_process_type(TimerProcessType p_type) {
+	if (timer_process_type == p_type) {
+		return;
+	}
+	switch (timer_process_type) {
+		case TIMER_PROCESS_TYPE_FRAMES: {
+			wait_time = (int)wait_time;
+			time_left = (int)time_left;
+		}; break;
+		case TIMER_PROCESS_TYPE_TIME:
+			break;
+	}
+	timer_process_type = p_type;
+	notify_property_list_changed();
+}
+
+Timer::TimerProcessType Timer::get_timer_process_type() const {
+	return timer_process_type;
+}
+
 void Timer::_set_process(bool p_process, bool p_force) {
 	switch (timer_process_callback) {
 		case TIMER_PROCESS_PHYSICS:
@@ -190,6 +230,14 @@ PackedStringArray Timer::get_configuration_warnings() const {
 	return warnings;
 }
 
+void Timer::_validate_property(PropertyInfo &p_property) const {
+	if (timer_process_type == TIMER_PROCESS_TYPE_FRAMES && p_property.name == "wait_time") {
+		p_property.type = Variant::INT;
+		p_property.hint = PROPERTY_HINT_NONE;
+		p_property.hint_string = "suffix:f";
+	}
+}
+
 void Timer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_wait_time", "time_sec"), &Timer::set_wait_time);
 	ClassDB::bind_method(D_METHOD("get_wait_time"), &Timer::get_wait_time);
@@ -213,9 +261,13 @@ void Timer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_timer_process_callback", "callback"), &Timer::set_timer_process_callback);
 	ClassDB::bind_method(D_METHOD("get_timer_process_callback"), &Timer::get_timer_process_callback);
 
+	ClassDB::bind_method(D_METHOD("set_timer_process_type", "type"), &Timer::set_timer_process_type);
+	ClassDB::bind_method(D_METHOD("get_timer_process_type"), &Timer::get_timer_process_type);
+
 	ADD_SIGNAL(MethodInfo("timeout"));
 
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "process_callback", PROPERTY_HINT_ENUM, "Physics,Idle"), "set_timer_process_callback", "get_timer_process_callback");
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "process_type", PROPERTY_HINT_ENUM, "Time,Frames"), "set_timer_process_type", "get_timer_process_type");
 	ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "wait_time", PROPERTY_HINT_RANGE, "0.001,4096,0.001,or_greater,exp,suffix:s"), "set_wait_time", "get_wait_time");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "one_shot"), "set_one_shot", "is_one_shot");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "autostart"), "set_autostart", "has_autostart");
@@ -224,6 +276,9 @@ void Timer::_bind_methods() {
 
 	BIND_ENUM_CONSTANT(TIMER_PROCESS_PHYSICS);
 	BIND_ENUM_CONSTANT(TIMER_PROCESS_IDLE);
+
+	BIND_ENUM_CONSTANT(TIMER_PROCESS_TYPE_TIME);
+	BIND_ENUM_CONSTANT(TIMER_PROCESS_TYPE_FRAMES);
 }
 
 Timer::Timer() {}

scene/main/timer.h

@@ -47,13 +47,21 @@ class Timer : public Node {
 protected:
 	void _notification(int p_what);
 	static void _bind_methods();
+	void _validate_property(PropertyInfo &p_property) const;
 
 public:
 	enum TimerProcessCallback {
 		TIMER_PROCESS_PHYSICS,
 		TIMER_PROCESS_IDLE,
 	};
 
+	// Type instead of Mode to prevent name collisions when upgrading from 3 to 4
+	// Godot 3 used TimerProcessMode which is now TimerProcessCallback
+	enum TimerProcessType {
+		TIMER_PROCESS_TYPE_TIME,
+		TIMER_PROCESS_TYPE_FRAMES,
+	};
+
 	void set_wait_time(double p_time);
 	double get_wait_time() const;
 
@@ -77,13 +85,19 @@ class Timer : public Node {
 
 	void set_timer_process_callback(TimerProcessCallback p_callback);
 	TimerProcessCallback get_timer_process_callback() const;
+
+	void set_timer_process_type(TimerProcessType p_type);
+	TimerProcessType get_timer_process_type() const;
+
 	Timer();
 
 private:
 	TimerProcessCallback timer_process_callback = TIMER_PROCESS_IDLE;
+	TimerProcessType timer_process_type = TIMER_PROCESS_TYPE_TIME;
 	void _set_process(bool p_process, bool p_force = false);
 };
 
 VARIANT_ENUM_CAST(Timer::TimerProcessCallback);
+VARIANT_ENUM_CAST(Timer::TimerProcessType);
 
 #endif // TIMER_H