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[blank.git] / src / world / EntityController.hpp

diff --git a/src/world/EntityController.hpp b/src/world/EntityController.hpp
index 526a3222fa4d985fc53094ab7e2c649376dfdd2e..ce3d0cf00998fbccf7826aa052766aca7a66cbe1 100644 (file)
--- a/src/world/EntityController.hpp
+++ b/src/world/EntityController.hpp
@@ -26,8 +26,15 @@ struct EntityController {
                const glm::vec3 &add,
                float max
        ) noexcept;
-       /// give a force that makes state's velocity converge with given target velocity
-       /// over 1/n seconds
+       /// 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,
@@ -35,6 +42,25 @@ struct EntityController {
        ) 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);
+       }
 
 };