Polish kinematic movement

game/components.c

@@ -32,7 +32,7 @@ ECS_TAG_DECLARE(Selectable);
 ECS_TAG_DECLARE(Selected);
 
 ECS_COMPONENT_DECLARE(Worker);
-ECS_TAG_DECLARE(Unit);
+ECS_COMPONENT_DECLARE(Unit);
 ECS_TAG_DECLARE(Storage);
 ECS_TAG_DECLARE(Harvestable);
 ECS_TAG_DECLARE(Buildable);
@@ -69,7 +69,7 @@ void initComponentIDs(ecs_world_t *ecs) {
     ECS_TAG_DEFINE(ecs, Selected);
 
     ECS_COMPONENT_DEFINE(ecs, Worker);
-    ECS_TAG_DEFINE(ecs, Unit);
+    ECS_COMPONENT_DEFINE(ecs, Unit);
     ECS_TAG_DEFINE(ecs, Storage);
     ECS_TAG_DEFINE(ecs, Harvestable);
     ECS_TAG_DEFINE(ecs, Buildable);

game/components.h

@@ -191,7 +191,12 @@ extern ECS_COMPONENT_DECLARE(Worker);
 
 // Unit can:
 // - Attack
-extern ECS_TAG_DECLARE(Unit);
+typedef struct Unit {
+    f32 maxSpeed;
+    f32 acceleration;
+    f32 deceleration;
+} Unit;
+extern ECS_COMPONENT_DECLARE(Unit);
 extern ECS_TAG_DECLARE(Storage);
 extern ECS_TAG_DECLARE(Harvestable);
 extern ECS_TAG_DECLARE(Buildable);

game/entity_factory.c

@@ -36,7 +36,11 @@ ecs_entity_t entityCreateWorker(const Position position, Game *game) {
     });
     ecs_set(ECS, e, UnitAction, { NULL, NULL });
     ecs_add_id(ECS, e, Selectable);
-    ecs_add_id(ECS, e, Unit);
+    ecs_set(ECS, e, Unit, {
+        .acceleration = 80.0f,
+        .maxSpeed = 15.0f,
+        .deceleration = 0.1f
+    });
     ecs_set(ECS, e, Worker, {
         .collectSpeed = 0.8f,
         .depositSpeed = 0.2f,

game/systems/s_entity.c

@@ -61,67 +61,54 @@ void entityUpdateSpatialID(ecs_iter_t *it) {
 
 void entityUpdateKinematic(ecs_iter_t *it) {
     Position *position = ecs_field(it, Position, 1);
-    Rotation *rotation = ecs_field(it, Rotation, 2);
-    Velocity *velocity = ecs_field(it, Velocity, 3);
-    Steering *steering = ecs_field(it, Steering, 4);
+    Velocity *velocity = ecs_field(it, Velocity, 2);
+    Steering *steering = ecs_field(it, Steering, 3);
+    Unit     *unit     = ecs_field(it, Unit, 4);
 
     f32 dt = it->delta_time;
 
     for (i32 i = 0; i < it->count; i++) {
-        // Update position and rotation
-        // position += velocity * dt
-        position[i] = Vector2Add(position[i], Vector2Scale(velocity[i], dt));
 
-        // Update velocity and angular velocity
-        // velocity += steering.liner * dt
-        velocity[i] = Vector2Add(velocity[i], Vector2Scale(steering[i], dt * 10));
+        steering[i] = Vector2Normalize(steering[i]);
+        // velocity += steering * dt
+        Vector2 accel = Vector2Scale(steering[i], dt);
+        accel = Vector2Scale(accel, unit->acceleration);
+        velocity[i] = Vector2Add(velocity[i], accel);
 
+        // Apply deceleration
         if (Vector2LengthSqr(steering[i]) == 0) {
-            // Decay velocity
-            velocity[i] = Vector2Scale(velocity[i], 1 - (dt * 5.0f));
+            // velocity *= (1.0 - decel)
+            velocity[i] = Vector2Scale(velocity[i], 1.0 - unit->deceleration);
         }
+
         // Reset steering
         steering[i] = Vector2Zero();
 
-        {
-            const InputState *input = ecs_singleton_get(ECS, InputState);
-
-            Vector2 mouse = input->mouseDownWorld;
-            f32 rot = Vector2Angle(position[i], mouse) + 270 * DEG2RAD;
-            //rotation[i] = rot;
-        }
-
         // Check for speeding and clip
-        const f32 maxSpeed = 15.0f;
+        const f32 maxSpeed = unit->maxSpeed;
         if (Vector2Length(velocity[i]) > maxSpeed) {
             velocity[i] = Vector2Normalize(velocity[i]);
             velocity[i] = Vector2Scale(velocity[i], maxSpeed);
         }
+
+        // position += velocity * dt
+        position[i] = Vector2Add(position[i], Vector2Scale(velocity[i], dt));
     }
 }
 
 void entityMoveToTarget(ecs_iter_t *it) {
     Position *position = ecs_field(it, Position, 1);
-    Rotation *rotation = ecs_field(it, Rotation, 2);
-    Velocity *velocity = ecs_field(it, Velocity, 3);
+    Velocity *velocity = ecs_field(it, Velocity, 2);
 
-    TargetPosition *targetPos = ecs_field(it, TargetPosition, 4);
-    Steering       *steering  = ecs_field(it, Steering, 5);
+    TargetPosition *targetPos = ecs_field(it, TargetPosition, 3);
+    Steering       *steering  = ecs_field(it, Steering, 4);
 
     for (i32 i = 0; i < it->count; i++) {
         Position target = targetPos[i];
         steering[i] = Vector2Subtract(target, position[i]);
         f32 dst = Vector2LengthSqr(steering[i]);
-        f32 maxAccel = 10.0f;
-        steering[i] = Vector2Normalize(steering[i]);
-        steering[i] = Vector2Scale(steering[i], maxAccel);
 
-        if (Vector2Length(velocity[i]) > 10.0f) {
-            f32 rot = Vector2Angle(position[i], target);
-            //rotation[i] = rot;
-        }
-
-        if (dst < 8.0f) {
+        if (dst < 2.0f) {
             // Arrived
             ecs_remove(ECS, it->entities[i], TargetPosition);
         }

game/systems/s_input.c

@@ -53,7 +53,7 @@ void inputPrimaryAction(Game *game, InputState *input) {
         resetInputState(input);
         input->state = INPUT_SELECTED_UNITS;
     } else if (isInputBtnJustUp(input, primaryBtn)) {
-        if (pickEntity(game->entityGrid, input->mouseDownWorld, Unit)) {
+        if (pickEntity(game->entityGrid, input->mouseDownWorld, ecs_id(Unit))) {
             resetInputState(input);
             input->state = INPUT_SELECTED_UNITS;
         } else if (pickEntity(game->entityGrid, input->mouseDownWorld, Harvestable)) {
@@ -432,7 +432,7 @@ void pickUnits(BzSpatialGrid *entityGrid, Rectangle area) {
     BzSpatialGridIter it = bzSpatialGridIter(entityGrid, area.x, area.y, area.width, area.height);
     while (bzSpatialGridQueryNext(&it)) {
         ecs_entity_t entity = *(ecs_entity_t *) it.data;
-        if (!ecs_has_id(ECS, entity, Unit)) continue;
+        if (!ecs_has_id(ECS, entity, ecs_id(Unit))) continue;
         Rectangle bounds;
         if (!getEntityBounds(entity, NULL, NULL, &bounds)) continue;
 

game/systems/systems.c

@@ -39,9 +39,9 @@ void setupSystems() {
     ECS_OBSERVER(ECS, entityPathRemove, EcsOnRemove, Path);
 
     ECS_SYSTEM(ECS, entityUpdateSpatialID, EcsOnUpdate, Position, Size, Velocity, SpatialGridID);
-    ECS_SYSTEM(ECS, entityUpdateKinematic, EcsOnUpdate, Position, Rotation, Velocity, Steering);
+    ECS_SYSTEM(ECS, entityUpdateKinematic, EcsOnUpdate, Position, Velocity, Steering, Unit);
 
-    ECS_SYSTEM(ECS, entityMoveToTarget, EcsOnUpdate, Position, Rotation, Velocity, TargetPosition, Steering);
+    ECS_SYSTEM(ECS, entityMoveToTarget, EcsOnUpdate, Position, Velocity, TargetPosition, Steering);
     ECS_SYSTEM(ECS, entityFollowPath, EcsOnUpdate, Path);
 
     ECS_SYSTEM(ECS, handleUnitActionsSystem, EcsOnUpdate, UnitAction);

game/systems/systems.h

@@ -81,18 +81,17 @@ void entityUpdateSpatialID(ecs_iter_t *it);
 /*
  * 0: Game (singleton) for collisions
  * 1: Position
- * 2: Rotation
- * 3: Velocity
- * 4: Steering
+ * 2: Velocity
+ * 3: Steering
+ * 4: Unit
  */
 void entityUpdateKinematic(ecs_iter_t *it);
 
 /*
  * 1: Position
- * 2: Rotation
- * 3: Velocity
- * 4: TargetPosition
- * 5: Steering
+ * 2: Velocity
+ * 3: TargetPosition
+ * 4: Steering
  */
 void entityMoveToTarget(ecs_iter_t *it);