Improve RigidDynamicBody force and torque API

Makes the API for forces and impulses more flexible, easier to
understand and harmonized between 2D and 3D.

Rigid bodies now have 3 sets of methods for forces and impulses:
-apply_impulse() for impulses (one-shot and time independent)
-apply_force() for forces (time dependent) applied for the current step
-add_constant_force() for forces that keeps being applied each step

Also updated the documentation to clarify the different methods and
parameters in rigid body nodes, body direct state and physics servers.

6 files changed, 400 insertions, 67 deletions

diff --git a/doc/classes/PhysicsDirectBodyState2D.xml b/doc/classes/PhysicsDirectBodyState2D.xml
index c33bd930be..fbadfd2702 100644
--- a/doc/classes/PhysicsDirectBodyState2D.xml
+++ b/doc/classes/PhysicsDirectBodyState2D.xml
@@ -11,26 +11,36 @@
 		<link title="Ray-casting">$DOCS_URL/tutorials/physics/ray-casting.html</link>
 	</tutorials>
 	<methods>
-		<method name="add_central_force">
+		<method name="add_constant_central_force">
 			<return type="void" />
-			<argument index="0" name="force" type="Vector2" />
+			<argument index="0" name="force" type="Vector2" default="Vector2(0, 0)" />
 			<description>
-				Adds a constant directional force without affecting rotation.
+				Adds a constant directional force without affecting rotation that keeps being applied over time until cleared with [code]constant_force = Vector2(0, 0)[/code].
+				This is equivalent to using [method add_constant_force] at the body's center of mass.
 			</description>
 		</method>
-		<method name="add_force">
+		<method name="add_constant_force">
 			<return type="void" />
 			<argument index="0" name="force" type="Vector2" />
 			<argument index="1" name="position" type="Vector2" default="Vector2(0, 0)" />
 			<description>
-				Adds a positioned force to the body. Both the force and the offset from the body origin are in global coordinates.
+				Adds a constant positioned force to the body that keeps being applied over time until cleared with [code]constant_force = Vector2(0, 0)[/code].
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
-		<method name="add_torque">
+		<method name="add_constant_torque">
 			<return type="void" />
 			<argument index="0" name="torque" type="float" />
 			<description>
-				Adds a constant rotational force.
+				Adds a constant rotational force without affecting position that keeps being applied over time until cleared with [code]constant_torque = 0[/code].
+			</description>
+		</method>
+		<method name="apply_central_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector2" default="Vector2(0, 0)" />
+			<description>
+				Applies a directional force without affecting rotation. A force is time dependent and meant to be applied every physics update.
+				This is equivalent to using [method apply_force] at the body's center of mass.
 			</description>
 		</method>
 		<method name="apply_central_impulse">
@@ -38,6 +48,17 @@
 			<argument index="0" name="impulse" type="Vector2" />
 			<description>
 				Applies a directional impulse without affecting rotation.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				This is equivalent to using [method apply_impulse] at the body's center of mass.
+			</description>
+		</method>
+		<method name="apply_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector2" />
+			<argument index="1" name="position" type="Vector2" default="Vector2(0, 0)" />
+			<description>
+				Applies a positioned force to the body. A force is time dependent and meant to be applied every physics update.
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
 		<method name="apply_impulse">
@@ -45,14 +66,38 @@
 			<argument index="0" name="impulse" type="Vector2" />
 			<argument index="1" name="position" type="Vector2" default="Vector2(0, 0)" />
 			<description>
-				Applies a positioned impulse to the body. An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise). The offset uses the rotation of the global coordinate system, but is centered at the object's origin.
+				Applies a positioned impulse to the body.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="apply_torque">
+			<return type="void" />
+			<argument index="0" name="torque" type="float" />
+			<description>
+				Applies a rotational force without affecting position. A force is time dependent and meant to be applied every physics update.
 			</description>
 		</method>
 		<method name="apply_torque_impulse">
 			<return type="void" />
 			<argument index="0" name="impulse" type="float" />
 			<description>
-				Applies a rotational impulse to the body.
+				Applies a rotational impulse to the body without affecting the position.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+			</description>
+		</method>
+		<method name="get_constant_force" qualifiers="const">
+			<return type="Vector2" />
+			<description>
+				Returns the body's total constant positional forces applied during each physics update.
+				See [method add_constant_force] and [method add_constant_central_force].
+			</description>
+		</method>
+		<method name="get_constant_torque" qualifiers="const">
+			<return type="float" />
+			<description>
+				Returns the body's total constant rotational forces applied during each physics update.
+				See [method add_constant_torque].
 			</description>
 		</method>
 		<method name="get_contact_collider" qualifiers="const">
@@ -144,6 +189,22 @@
 				Calls the built-in force integration code.
 			</description>
 		</method>
+		<method name="set_constant_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector2" />
+			<description>
+				Sets the body's total constant positional forces applied during each physics update.
+				See [method add_constant_force] and [method add_constant_central_force].
+			</description>
+		</method>
+		<method name="set_constant_torque">
+			<return type="void" />
+			<argument index="0" name="torque" type="float" />
+			<description>
+				Sets the body's total constant rotational forces applied during each physics update.
+				See [method add_constant_torque].
+			</description>
+		</method>
 	</methods>
 	<members>
 		<member name="angular_velocity" type="float" setter="set_angular_velocity" getter="get_angular_velocity">
diff --git a/doc/classes/PhysicsDirectBodyState3D.xml b/doc/classes/PhysicsDirectBodyState3D.xml
index 7aa46dec2f..58c4294d66 100644
--- a/doc/classes/PhysicsDirectBodyState3D.xml
+++ b/doc/classes/PhysicsDirectBodyState3D.xml
@@ -11,35 +11,54 @@
 		<link title="Ray-casting">$DOCS_URL/tutorials/physics/ray-casting.html</link>
 	</tutorials>
 	<methods>
-		<method name="add_central_force">
+		<method name="add_constant_central_force">
 			<return type="void" />
 			<argument index="0" name="force" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
-				Adds a constant directional force without affecting rotation.
-				This is equivalent to [code]add_force(force, Vector3(0,0,0))[/code].
+				Adds a constant directional force without affecting rotation that keeps being applied over time until cleared with [code]constant_force = Vector3(0, 0, 0)[/code].
+				This is equivalent to using [method add_constant_force] at the body's center of mass.
 			</description>
 		</method>
-		<method name="add_force">
+		<method name="add_constant_force">
 			<return type="void" />
 			<argument index="0" name="force" type="Vector3" />
 			<argument index="1" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
-				Adds a positioned force to the body. Both the force and the offset from the body origin are in global coordinates.
+				Adds a constant positioned force to the body that keeps being applied over time until cleared with [code]constant_force = Vector3(0, 0, 0)[/code].
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
-		<method name="add_torque">
+		<method name="add_constant_torque">
 			<return type="void" />
 			<argument index="0" name="torque" type="Vector3" />
 			<description>
-				Adds a constant rotational force without affecting position.
+				Adds a constant rotational force without affecting position that keeps being applied over time until cleared with [code]constant_torque = Vector3(0, 0, 0)[/code].
+			</description>
+		</method>
+		<method name="apply_central_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector3" default="Vector3(0, 0, 0)" />
+			<description>
+				Applies a directional force without affecting rotation. A force is time dependent and meant to be applied every physics update.
+				This is equivalent to using [method apply_force] at the body's center of mass.
 			</description>
 		</method>
 		<method name="apply_central_impulse">
 			<return type="void" />
 			<argument index="0" name="impulse" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
-				Applies a single directional impulse without affecting rotation.
-				This is equivalent to [code]apply_impulse(Vector3(0, 0, 0), impulse)[/code].
+				Applies a directional impulse without affecting rotation.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				This is equivalent to using [method apply_impulse] at the body's center of mass.
+			</description>
+		</method>
+		<method name="apply_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector3" />
+			<argument index="1" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
+			<description>
+				Applies a positioned force to the body. A force is time dependent and meant to be applied every physics update.
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
 		<method name="apply_impulse">
@@ -47,14 +66,38 @@
 			<argument index="0" name="impulse" type="Vector3" />
 			<argument index="1" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
-				Applies a positioned impulse to the body. An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason it should only be used when simulating one-time impacts. The position uses the rotation of the global coordinate system, but is centered at the object's origin.
+				Applies a positioned impulse to the body.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="apply_torque">
+			<return type="void" />
+			<argument index="0" name="torque" type="Vector3" />
+			<description>
+				Applies a rotational force without affecting position. A force is time dependent and meant to be applied every physics update.
 			</description>
 		</method>
 		<method name="apply_torque_impulse">
 			<return type="void" />
 			<argument index="0" name="impulse" type="Vector3" />
 			<description>
-				Apply a torque impulse (which will be affected by the body mass and shape). This will rotate the body around the vector [code]j[/code] passed as parameter.
+				Applies a rotational impulse to the body without affecting the position.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+			</description>
+		</method>
+		<method name="get_constant_force" qualifiers="const">
+			<return type="Vector3" />
+			<description>
+				Returns the body's total constant positional forces applied during each physics update.
+				See [method add_constant_force] and [method add_constant_central_force].
+			</description>
+		</method>
+		<method name="get_constant_torque" qualifiers="const">
+			<return type="Vector3" />
+			<description>
+				Returns the body's total constant rotational forces applied during each physics update.
+				See [method add_constant_torque].
 			</description>
 		</method>
 		<method name="get_contact_collider" qualifiers="const">
@@ -153,6 +196,22 @@
 				Calls the built-in force integration code.
 			</description>
 		</method>
+		<method name="set_constant_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector3" />
+			<description>
+				Sets the body's total constant positional forces applied during each physics update.
+				See [method add_constant_force] and [method add_constant_central_force].
+			</description>
+		</method>
+		<method name="set_constant_torque">
+			<return type="void" />
+			<argument index="0" name="torque" type="Vector3" />
+			<description>
+				Sets the body's total constant rotational forces applied during each physics update.
+				See [method add_constant_torque].
+			</description>
+		</method>
 	</methods>
 	<members>
 		<member name="angular_velocity" type="Vector3" setter="set_angular_velocity" getter="get_angular_velocity">
diff --git a/doc/classes/PhysicsServer2D.xml b/doc/classes/PhysicsServer2D.xml
index bfb4ca58ef..624f5e7b17 100644
--- a/doc/classes/PhysicsServer2D.xml
+++ b/doc/classes/PhysicsServer2D.xml
@@ -208,28 +208,39 @@
 				Sets the transform matrix for an area.
 			</description>
 		</method>
-		<method name="body_add_central_force">
+		<method name="body_add_collision_exception">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
-			<argument index="1" name="force" type="Vector2" />
+			<argument index="1" name="excepted_body" type="RID" />
 			<description>
+				Adds a body to the list of bodies exempt from collisions.
 			</description>
 		</method>
-		<method name="body_add_collision_exception">
+		<method name="body_add_constant_central_force">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
-			<argument index="1" name="excepted_body" type="RID" />
+			<argument index="1" name="force" type="Vector2" />
 			<description>
-				Adds a body to the list of bodies exempt from collisions.
+				Adds a constant directional force without affecting rotation that keeps being applied over time until cleared with [code]body_set_constant_force(body, Vector2(0, 0))[/code].
+				This is equivalent to using [method body_add_constant_force] at the body's center of mass.
 			</description>
 		</method>
-		<method name="body_add_force">
+		<method name="body_add_constant_force">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
 			<argument index="1" name="force" type="Vector2" />
 			<argument index="2" name="position" type="Vector2" default="Vector2(0, 0)" />
 			<description>
-				Adds a positioned force to the applied force and torque. As with [method body_apply_impulse], both the force and the offset from the body origin are in global coordinates. A force differs from an impulse in that, while the two are forces, the impulse clears itself after being applied.
+				Adds a constant positioned force to the body that keeps being applied over time until cleared with [code]body_set_constant_force(body, Vector2(0, 0))[/code].
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="body_add_constant_torque">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="torque" type="float" />
+			<description>
+				Adds a constant rotational force without affecting position that keeps being applied over time until cleared with [code]body_set_constant_torque(body, 0)[/code].
 			</description>
 		</method>
 		<method name="body_add_shape">
@@ -242,11 +253,13 @@
 				Adds a shape to the body, along with a transform matrix. Shapes are usually referenced by their index, so you should track which shape has a given index.
 			</description>
 		</method>
-		<method name="body_add_torque">
+		<method name="body_apply_central_force">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
-			<argument index="1" name="torque" type="float" />
+			<argument index="1" name="force" type="Vector2" />
 			<description>
+				Applies a directional force without affecting rotation. A force is time dependent and meant to be applied every physics update.
+				This is equivalent to using [method body_apply_force] at the body's center of mass.
 			</description>
 		</method>
 		<method name="body_apply_central_impulse">
@@ -254,6 +267,19 @@
 			<argument index="0" name="body" type="RID" />
 			<argument index="1" name="impulse" type="Vector2" />
 			<description>
+				Applies a directional impulse without affecting rotation.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				This is equivalent to using [method body_apply_impulse] at the body's center of mass.
+			</description>
+		</method>
+		<method name="body_apply_force">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="force" type="Vector2" />
+			<argument index="2" name="position" type="Vector2" default="Vector2(0, 0)" />
+			<description>
+				Applies a positioned force to the body. A force is time dependent and meant to be applied every physics update.
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
 		<method name="body_apply_impulse">
@@ -262,7 +288,17 @@
 			<argument index="1" name="impulse" type="Vector2" />
 			<argument index="2" name="position" type="Vector2" default="Vector2(0, 0)" />
 			<description>
-				Adds a positioned impulse to the applied force and torque. Both the force and the offset from the body origin are in global coordinates.
+				Applies a positioned impulse to the body.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="body_apply_torque">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="torque" type="float" />
+			<description>
+				Applies a rotational force without affecting position. A force is time dependent and meant to be applied every physics update.
 			</description>
 		</method>
 		<method name="body_apply_torque_impulse">
@@ -270,6 +306,8 @@
 			<argument index="0" name="body" type="RID" />
 			<argument index="1" name="impulse" type="float" />
 			<description>
+				Applies a rotational impulse to the body without affecting the position.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
 			</description>
 		</method>
 		<method name="body_attach_canvas_instance_id">
@@ -320,6 +358,22 @@
 				Returns the physics layer or layers a body can collide with.
 			</description>
 		</method>
+		<method name="body_get_constant_force" qualifiers="const">
+			<return type="Vector2" />
+			<argument index="0" name="body" type="RID" />
+			<description>
+				Returns the body's total constant positional forces applied during each physics update.
+				See [method body_add_constant_force] and [method body_add_constant_central_force].
+			</description>
+		</method>
+		<method name="body_get_constant_torque" qualifiers="const">
+			<return type="float" />
+			<argument index="0" name="body" type="RID" />
+			<description>
+				Returns the body's total constant rotational forces applied during each physics update.
+				See [method body_add_constant_torque].
+			</description>
+		</method>
 		<method name="body_get_continuous_collision_detection_mode" qualifiers="const">
 			<return type="int" enum="PhysicsServer2D.CCDMode" />
 			<argument index="0" name="body" type="RID" />
@@ -455,6 +509,24 @@
 				Sets the physics layer or layers a body can collide with.
 			</description>
 		</method>
+		<method name="body_set_constant_force">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="force" type="Vector2" />
+			<description>
+				Sets the body's total constant positional forces applied during each physics update.
+				See [method body_add_constant_force] and [method body_add_constant_central_force].
+			</description>
+		</method>
+		<method name="body_set_constant_torque">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="torque" type="float" />
+			<description>
+				Sets the body's total constant rotational forces applied during each physics update.
+				See [method body_add_constant_torque].
+			</description>
+		</method>
 		<method name="body_set_continuous_collision_detection_mode">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
diff --git a/doc/classes/PhysicsServer3D.xml b/doc/classes/PhysicsServer3D.xml
index b264590055..16c195c6dc 100644
--- a/doc/classes/PhysicsServer3D.xml
+++ b/doc/classes/PhysicsServer3D.xml
@@ -202,27 +202,39 @@
 				Sets the transform matrix for an area.
 			</description>
 		</method>
-		<method name="body_add_central_force">
+		<method name="body_add_collision_exception">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
-			<argument index="1" name="force" type="Vector3" />
+			<argument index="1" name="excepted_body" type="RID" />
 			<description>
+				Adds a body to the list of bodies exempt from collisions.
 			</description>
 		</method>
-		<method name="body_add_collision_exception">
+		<method name="body_add_constant_central_force">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
-			<argument index="1" name="excepted_body" type="RID" />
+			<argument index="1" name="force" type="Vector3" />
 			<description>
-				Adds a body to the list of bodies exempt from collisions.
+				Adds a constant directional force without affecting rotation that keeps being applied over time until cleared with [code]body_set_constant_force(body, Vector3(0, 0, 0))[/code].
+				This is equivalent to using [method body_add_constant_force] at the body's center of mass.
 			</description>
 		</method>
-		<method name="body_add_force">
+		<method name="body_add_constant_force">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
 			<argument index="1" name="force" type="Vector3" />
 			<argument index="2" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
+				Adds a constant positioned force to the body that keeps being applied over time until cleared with [code]body_set_constant_force(body, Vector3(0, 0, 0))[/code].
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="body_add_constant_torque">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="torque" type="Vector3" />
+			<description>
+				Adds a constant rotational force without affecting position that keeps being applied over time until cleared with [code]body_set_constant_torque(body, Vector3(0, 0, 0))[/code].
 			</description>
 		</method>
 		<method name="body_add_shape">
@@ -235,11 +247,13 @@
 				Adds a shape to the body, along with a transform matrix. Shapes are usually referenced by their index, so you should track which shape has a given index.
 			</description>
 		</method>
-		<method name="body_add_torque">
+		<method name="body_apply_central_force">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
-			<argument index="1" name="torque" type="Vector3" />
+			<argument index="1" name="force" type="Vector3" />
 			<description>
+				Applies a directional force without affecting rotation. A force is time dependent and meant to be applied every physics update.
+				This is equivalent to using [method body_apply_force] at the body's center of mass.
 			</description>
 		</method>
 		<method name="body_apply_central_impulse">
@@ -247,6 +261,19 @@
 			<argument index="0" name="body" type="RID" />
 			<argument index="1" name="impulse" type="Vector3" />
 			<description>
+				Applies a directional impulse without affecting rotation.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				This is equivalent to using [method body_apply_impulse] at the body's center of mass.
+			</description>
+		</method>
+		<method name="body_apply_force">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="force" type="Vector3" />
+			<argument index="2" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
+			<description>
+				Applies a positioned force to the body. A force is time dependent and meant to be applied every physics update.
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
 		<method name="body_apply_impulse">
@@ -255,7 +282,17 @@
 			<argument index="1" name="impulse" type="Vector3" />
 			<argument index="2" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
-				Gives the body a push at a [code]position[/code] in the direction of the [code]impulse[/code].
+				Applies a positioned impulse to the body.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="body_apply_torque">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="torque" type="Vector3" />
+			<description>
+				Applies a rotational force without affecting position. A force is time dependent and meant to be applied every physics update.
 			</description>
 		</method>
 		<method name="body_apply_torque_impulse">
@@ -263,7 +300,8 @@
 			<argument index="0" name="body" type="RID" />
 			<argument index="1" name="impulse" type="Vector3" />
 			<description>
-				Gives the body a push to rotate it.
+				Applies a rotational impulse to the body without affecting the position.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
 			</description>
 		</method>
 		<method name="body_attach_object_instance_id">
@@ -301,6 +339,22 @@
 -
 			</description>
 		</method>
+		<method name="body_get_constant_force" qualifiers="const">
+			<return type="Vector3" />
+			<argument index="0" name="body" type="RID" />
+			<description>
+				Returns the body's total constant positional forces applied during each physics update.
+				See [method body_add_constant_force] and [method body_add_constant_central_force].
+			</description>
+		</method>
+		<method name="body_get_constant_torque" qualifiers="const">
+			<return type="Vector3" />
+			<argument index="0" name="body" type="RID" />
+			<description>
+				Returns the body's total constant rotational forces applied during each physics update.
+				See [method body_add_constant_torque].
+			</description>
+		</method>
 		<method name="body_get_direct_state">
 			<return type="PhysicsDirectBodyState3D" />
 			<argument index="0" name="body" type="RID" />
@@ -452,6 +506,24 @@
 				Sets the physics layer or layers a body can collide with.
 			</description>
 		</method>
+		<method name="body_set_constant_force">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="force" type="Vector3" />
+			<description>
+				Sets the body's total constant positional forces applied during each physics update.
+				See [method body_add_constant_force] and [method body_add_constant_central_force].
+			</description>
+		</method>
+		<method name="body_set_constant_torque">
+			<return type="void" />
+			<argument index="0" name="body" type="RID" />
+			<argument index="1" name="torque" type="Vector3" />
+			<description>
+				Sets the body's total constant rotational forces applied during each physics update.
+				See [method body_add_constant_torque].
+			</description>
+		</method>
 		<method name="body_set_enable_continuous_collision_detection">
 			<return type="void" />
 			<argument index="0" name="body" type="RID" />
diff --git a/doc/classes/RigidDynamicBody2D.xml b/doc/classes/RigidDynamicBody2D.xml
index b8680b99b3..0026c49651 100644
--- a/doc/classes/RigidDynamicBody2D.xml
+++ b/doc/classes/RigidDynamicBody2D.xml
@@ -22,26 +22,36 @@
 				Allows you to read and safely modify the simulation state for the object. Use this instead of [method Node._physics_process] if you need to directly change the body's [code]position[/code] or other physics properties. By default, it works in addition to the usual physics behavior, but [member custom_integrator] allows you to disable the default behavior and write custom force integration for a body.
 			</description>
 		</method>
-		<method name="add_central_force">
+		<method name="add_constant_central_force">
 			<return type="void" />
 			<argument index="0" name="force" type="Vector2" />
 			<description>
-				Adds a constant directional force without affecting rotation.
+				Adds a constant directional force without affecting rotation that keeps being applied over time until cleared with [code]constant_force = Vector2(0, 0)[/code].
+				This is equivalent to using [method add_constant_force] at the body's center of mass.
 			</description>
 		</method>
-		<method name="add_force">
+		<method name="add_constant_force">
 			<return type="void" />
 			<argument index="0" name="force" type="Vector2" />
 			<argument index="1" name="position" type="Vector2" default="Vector2(0, 0)" />
 			<description>
-				Adds a positioned force to the body. Both the force and the offset from the body origin are in global coordinates.
+				Adds a constant positioned force to the body that keeps being applied over time until cleared with [code]constant_force = Vector2(0, 0)[/code].
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
-		<method name="add_torque">
+		<method name="add_constant_torque">
 			<return type="void" />
 			<argument index="0" name="torque" type="float" />
 			<description>
-				Adds a constant rotational force.
+				Adds a constant rotational force without affecting position that keeps being applied over time until cleared with [code]constant_torque = 0[/code].
+			</description>
+		</method>
+		<method name="apply_central_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector2" />
+			<description>
+				Applies a directional force without affecting rotation. A force is time dependent and meant to be applied every physics update.
+				This is equivalent to using [method apply_force] at the body's center of mass.
 			</description>
 		</method>
 		<method name="apply_central_impulse">
@@ -49,6 +59,17 @@
 			<argument index="0" name="impulse" type="Vector2" default="Vector2(0, 0)" />
 			<description>
 				Applies a directional impulse without affecting rotation.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				This is equivalent to using [method apply_impulse] at the body's center of mass.
+			</description>
+		</method>
+		<method name="apply_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector2" />
+			<argument index="1" name="position" type="Vector2" default="Vector2(0, 0)" />
+			<description>
+				Applies a positioned force to the body. A force is time dependent and meant to be applied every physics update.
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
 		<method name="apply_impulse">
@@ -56,14 +77,24 @@
 			<argument index="0" name="impulse" type="Vector2" />
 			<argument index="1" name="position" type="Vector2" default="Vector2(0, 0)" />
 			<description>
-				Applies a positioned impulse to the body. An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason it should only be used when simulating one-time impacts (use the "_force" functions otherwise). The position uses the rotation of the global coordinate system, but is centered at the object's origin.
+				Applies a positioned impulse to the body.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="apply_torque">
+			<return type="void" />
+			<argument index="0" name="torque" type="float" />
+			<description>
+				Applies a rotational force without affecting position. A force is time dependent and meant to be applied every physics update.
 			</description>
 		</method>
 		<method name="apply_torque_impulse">
 			<return type="void" />
 			<argument index="0" name="torque" type="float" />
 			<description>
-				Applies a rotational impulse to the body.
+				Applies a rotational impulse to the body without affecting the position.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
 			</description>
 		</method>
 		<method name="get_colliding_bodies" qualifiers="const">
@@ -92,12 +123,6 @@
 		<member name="angular_velocity" type="float" setter="set_angular_velocity" getter="get_angular_velocity" default="0.0">
 			The body's rotational velocity.
 		</member>
-		<member name="applied_force" type="Vector2" setter="set_applied_force" getter="get_applied_force" default="Vector2(0, 0)">
-			The body's total applied force.
-		</member>
-		<member name="applied_torque" type="float" setter="set_applied_torque" getter="get_applied_torque" default="0.0">
-			The body's total applied torque.
-		</member>
 		<member name="can_sleep" type="bool" setter="set_can_sleep" getter="is_able_to_sleep" default="true">
 			If [code]true[/code], the body can enter sleep mode when there is no movement. See [member sleeping].
 		</member>
@@ -108,6 +133,14 @@
 		<member name="center_of_mass_mode" type="int" setter="set_center_of_mass_mode" getter="get_center_of_mass_mode" enum="RigidDynamicBody2D.CenterOfMassMode" default="0">
 			Defines the way the body's center of mass is set. See [enum CenterOfMassMode] for possible values.
 		</member>
+		<member name="constant_force" type="Vector2" setter="set_constant_force" getter="get_constant_force" default="Vector2(0, 0)">
+			The body's total constant positional forces applied during each physics update.
+			See [method add_constant_force] and [method add_constant_central_force].
+		</member>
+		<member name="constant_torque" type="float" setter="set_constant_torque" getter="get_constant_torque" default="0.0">
+			The body's total constant rotational forces applied during each physics update.
+			See [method add_constant_torque].
+		</member>
 		<member name="contact_monitor" type="bool" setter="set_contact_monitor" getter="is_contact_monitor_enabled" default="false">
 			If [code]true[/code], the body will emit signals when it collides with another RigidDynamicBody2D. See also [member contacts_reported].
 		</member>
@@ -159,7 +192,7 @@
 			If a material is assigned to this property, it will be used instead of any other physics material, such as an inherited one.
 		</member>
 		<member name="sleeping" type="bool" setter="set_sleeping" getter="is_sleeping" default="false">
-			If [code]true[/code], the body will not move and will not calculate forces until woken up by another body through, for example, a collision, or by using the [method apply_impulse] or [method add_force] methods.
+			If [code]true[/code], the body will not move and will not calculate forces until woken up by another body through, for example, a collision, or by using the [method apply_impulse] or [method apply_force] methods.
 		</member>
 	</members>
 	<signals>
diff --git a/doc/classes/RigidDynamicBody3D.xml b/doc/classes/RigidDynamicBody3D.xml
index c75055e0df..3dffdcbf83 100644
--- a/doc/classes/RigidDynamicBody3D.xml
+++ b/doc/classes/RigidDynamicBody3D.xml
@@ -22,28 +22,36 @@
 				Called during physics processing, allowing you to read and safely modify the simulation state for the object. By default, it works in addition to the usual physics behavior, but the [member custom_integrator] property allows you to disable the default behavior and do fully custom force integration for a body.
 			</description>
 		</method>
-		<method name="add_central_force">
+		<method name="add_constant_central_force">
 			<return type="void" />
 			<argument index="0" name="force" type="Vector3" />
 			<description>
-				Adds a constant directional force (i.e. acceleration) without affecting rotation.
-				This is equivalent to [code]add_force(force, Vector3(0,0,0))[/code].
+				Adds a constant directional force without affecting rotation that keeps being applied over time until cleared with [code]constant_force = Vector3(0, 0, 0)[/code].
+				This is equivalent to using [method add_constant_force] at the body's center of mass.
 			</description>
 		</method>
-		<method name="add_force">
+		<method name="add_constant_force">
 			<return type="void" />
 			<argument index="0" name="force" type="Vector3" />
 			<argument index="1" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
-				Adds a constant directional force (i.e. acceleration).
-				The position uses the rotation of the global coordinate system, but is centered at the object's origin.
+				Adds a constant positioned force to the body that keeps being applied over time until cleared with [code]constant_force = Vector3(0, 0, 0)[/code].
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
-		<method name="add_torque">
+		<method name="add_constant_torque">
 			<return type="void" />
 			<argument index="0" name="torque" type="Vector3" />
 			<description>
-				Adds a constant rotational force (i.e. a motor) without affecting position.
+				Adds a constant rotational force without affecting position that keeps being applied over time until cleared with [code]constant_torque = Vector3(0, 0, 0)[/code].
+			</description>
+		</method>
+		<method name="apply_central_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector3" />
+			<description>
+				Applies a directional force without affecting rotation. A force is time dependent and meant to be applied every physics update.
+				This is equivalent to using [method apply_force] at the body's center of mass.
 			</description>
 		</method>
 		<method name="apply_central_impulse">
@@ -51,7 +59,17 @@
 			<argument index="0" name="impulse" type="Vector3" />
 			<description>
 				Applies a directional impulse without affecting rotation.
-				This is equivalent to [code]apply_impulse(Vector3(0,0,0), impulse)[/code].
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				This is equivalent to using [method apply_impulse] at the body's center of mass.
+			</description>
+		</method>
+		<method name="apply_force">
+			<return type="void" />
+			<argument index="0" name="force" type="Vector3" />
+			<argument index="1" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
+			<description>
+				Applies a positioned force to the body. A force is time dependent and meant to be applied every physics update.
+				[code]position[/code] is the offset from the body origin in global coordinates.
 			</description>
 		</method>
 		<method name="apply_impulse">
@@ -59,14 +77,24 @@
 			<argument index="0" name="impulse" type="Vector3" />
 			<argument index="1" name="position" type="Vector3" default="Vector3(0, 0, 0)" />
 			<description>
-				Applies a positioned impulse to the body. An impulse is time independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason it should only be used when simulating one-time impacts. The position uses the rotation of the global coordinate system, but is centered at the object's origin.
+				Applies a positioned impulse to the body.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
+				[code]position[/code] is the offset from the body origin in global coordinates.
+			</description>
+		</method>
+		<method name="apply_torque">
+			<return type="void" />
+			<argument index="0" name="torque" type="Vector3" />
+			<description>
+				Applies a rotational force without affecting position. A force is time dependent and meant to be applied every physics update.
 			</description>
 		</method>
 		<method name="apply_torque_impulse">
 			<return type="void" />
 			<argument index="0" name="impulse" type="Vector3" />
 			<description>
-				Applies a torque impulse which will be affected by the body mass and shape. This will rotate the body around the [code]impulse[/code] vector passed.
+				Applies a rotational impulse to the body without affecting the position.
+				An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason, it should only be used when simulating one-time impacts (use the "_force" functions otherwise).
 			</description>
 		</method>
 		<method name="get_colliding_bodies" qualifiers="const">
@@ -111,6 +139,14 @@
 		<member name="center_of_mass_mode" type="int" setter="set_center_of_mass_mode" getter="get_center_of_mass_mode" enum="RigidDynamicBody3D.CenterOfMassMode" default="0">
 			Defines the way the body's center of mass is set. See [enum CenterOfMassMode] for possible values.
 		</member>
+		<member name="constant_force" type="Vector3" setter="set_constant_force" getter="get_constant_force" default="Vector3(0, 0, 0)">
+			The body's total constant positional forces applied during each physics update.
+			See [method add_constant_force] and [method add_constant_central_force].
+		</member>
+		<member name="constant_torque" type="Vector3" setter="set_constant_torque" getter="get_constant_torque" default="Vector3(0, 0, 0)">
+			The body's total constant rotational forces applied during each physics update.
+			See [method add_constant_torque].
+		</member>
 		<member name="contact_monitor" type="bool" setter="set_contact_monitor" getter="is_contact_monitor_enabled" default="false">
 			If [code]true[/code], the RigidDynamicBody3D will emit signals when it collides with another RigidDynamicBody3D. See also [member contacts_reported].
 		</member>
@@ -162,7 +198,7 @@
 			If a material is assigned to this property, it will be used instead of any other physics material, such as an inherited one.
 		</member>
 		<member name="sleeping" type="bool" setter="set_sleeping" getter="is_sleeping" default="false">
-			If [code]true[/code], the body will not move and will not calculate forces until woken up by another body through, for example, a collision, or by using the [method apply_impulse] or [method add_force] methods.
+			If [code]true[/code], the body will not move and will not calculate forces until woken up by another body through, for example, a collision, or by using the [method apply_impulse] or [method apply_force] methods.
 		</member>
 	</members>
 	<signals>