X-Git-Url: http://git.localhorst.tv/?a=blobdiff_plain;f=src%2Fworld%2FEntityController.hpp;h=ce3d0cf00998fbccf7826aa052766aca7a66cbe1;hb=da21395e4900bf283ece7364c67d9bad27dca279;hp=8b14ca8a3d9606c687ba9c35da1107fa4682bb6d;hpb=150d065f431d665326fd8028748c48a74ad956bb;p=blank.git

diff --git a/src/world/EntityController.hpp b/src/world/EntityController.hpp
index 8b14ca8..ce3d0cf 100644
--- a/src/world/EntityController.hpp
+++ b/src/world/EntityController.hpp
@@ -1,13 +1,14 @@
 #ifndef BLANK_WORLD_ENTITYCONTROLLER_HPP_
 #define BLANK_WORLD_ENTITYCONTROLLER_HPP_
 
+#include "EntityState.hpp"
+
 #include <glm/glm.hpp>
 
 
 namespace blank {
 
 class Entity;
-class EntityState;
 
 struct EntityController {
 
@@ -15,7 +16,51 @@ struct EntityController {
 
 	virtual void Update(Entity &, float dt) = 0;
 
-	virtual glm::vec3 ControlForce(const EntityState &) const = 0;
+	virtual glm::vec3 ControlForce(const Entity &, const EntityState &) const = 0;
+
+
+	/// try to add as much of add to out so it doesn't exceed max
+	/// returns true if it's maxed out
+	static bool MaxOutForce(
+		glm::vec3 &out,
+		const glm::vec3 &add,
+		float max
+	) noexcept;
+	/// give a force that makes state come to a halt over 1/n seconds
+	static inline glm::vec3 Halt(
+		const EntityState &state,
+		float n
+	) noexcept {
+		return state.velocity * -n;
+	}
+	/// give a force that makes state's velocity converge with given
+	/// target velocity over 1/n seconds
+	static inline glm::vec3 TargetVelocity(
+		const glm::vec3 &target,
+		const EntityState &state,
+		float n
+	) noexcept {
+		return (target - state.velocity) * n;
+	}
+	/// give a force that makes state go after target with an attempted
+	/// acceleration over 1/n seconds and a speed of s
+	static inline glm::vec3 Seek(
+		const EntityState &state,
+		const EntityState &target,
+		float s,
+		float n
+	) noexcept {
+		return TargetVelocity(normalize(target.Diff(state)) * s, state, n);
+	}
+	/// opposite of seek
+	static inline glm::vec3 Flee(
+		const EntityState &state,
+		const EntityState &target,
+		float s,
+		float n
+	) noexcept {
+		return TargetVelocity(normalize(state.Diff(target)) * s, state, n);
+	}
 
 };