move camera logic to vis layer

src/pp/pp_sim/pp_sim_core.c

@@ -356,28 +356,6 @@ void S_TickForever(WaveLaneCtx *lane)
             ent->xf = xf;
         }
 
-        //////////////////////////////
-        //- Solve followers
-
-        for (S_Ent *ent = S_FirstEnt(&iter, world); ent->active; ent = S_NextEnt(&iter))
-        {
-            S_Ent *follow = S_EntFromKey(&lookup, ent->follow);
-            if (follow->active)
-            {
-                f32 follow_speed = 20 * sim_dt;
-                Vec2 look_ratio = Zi;
-                look_ratio.y = 0.25;
-                look_ratio.x = look_ratio.y / (16.0 / 9.0);
-
-                Vec2 target = MulXformV2(follow->xf, follow->local_shape.centroid);
-                target = AddVec2(target, MulVec2Vec2(follow->look, look_ratio));
-
-                Xform xf = ent->xf;
-                xf.og = LerpVec2(xf.og, target, follow_speed);
-                ent->xf = xf;
-            }
-        }
-
         //////////////////////////////
         //- Publish sim state
 

src/pp/pp_sim/pp_sim_core.h

@@ -49,11 +49,7 @@ Struct(S_Ent)
     Xform xf;
     S_Shape local_shape;
 
-    S_Key follow;
-    S_Key camera;
-
     f32 move_speed;
-
     Vec2 move;
     Vec2 look;
 

src/pp/pp_vis/pp_vis_core.c

@@ -139,6 +139,8 @@ void V_TickForever(WaveLaneCtx *lane)
 
         frame->time_ns = TimeNs();
         frame->tick = last_frame->tick + 1;
+        frame->dt_ns = frame->time_ns - last_frame->time_ns;
+        frame->dt = SecondsFromNs(frame->dt_ns);
 
         S_Iter iter = Zi;
         S_EntList spawn_ents = Zi;
@@ -149,9 +151,8 @@ void V_TickForever(WaveLaneCtx *lane)
         if (frame->tick == 1)
         {
             S_Key child_key = S_RandKey();
-            S_Key camera_key = S_RandKey();
 
-            i32 count = 2;
+            i32 count = 1;
             for (u64 i = 0; i < count; ++i)
             {
                 S_EntListNode *n = PushStruct(frame->arena, S_EntListNode);
@@ -165,7 +166,6 @@ void V_TickForever(WaveLaneCtx *lane)
                     case 0:
                     {
                         ent->key = V.player_key;
-                        ent->camera = camera_key;
                         ent->move_speed = 0.1;
                         {
                             ent->local_shape = S_ShapeFromDesc(
@@ -179,13 +179,6 @@ void V_TickForever(WaveLaneCtx *lane)
                         ent->has_weapon = 1;
                     } break;
 
-                    /* Test camera */
-                    case 1:
-                    {
-                        ent->key = camera_key;
-                        ent->follow = V.player_key;
-                    } break;
-
                     default:
                     {
                         Assert(0);
@@ -259,12 +252,22 @@ void V_TickForever(WaveLaneCtx *lane)
 
         f32 meters_per_draw_width = 20;
 
-        Vec2 camera_pos = Zi;
-        f32 camera_zoom = 1;
         {
-            S_Ent *player = S_EntFromKey(&V.lookup, V.player_key);
+            f32 lerp_ratio = 20 * frame->dt;
-            S_Ent *camera = S_EntFromKey(&V.lookup, player->camera);
+            Vec2 look_ratio = Zi;
-            camera_pos = MulXformV2(camera->xf, camera->local_shape.centroid);
+            look_ratio.y = 0.25;
+            look_ratio.x = look_ratio.y / (16.0 / 9.0);
+
+            Vec2 target_camera_pos = Zi;
+            f32 target_camera_zoom = 1;
+            {
+                S_Ent *player = S_EntFromKey(&V.lookup, V.player_key);
+                target_camera_pos = MulXformV2(player->xf, player->local_shape.centroid);
+                target_camera_pos = AddVec2(target_camera_pos, MulVec2Vec2(player->look, look_ratio));
+            }
+
+            frame->camera_pos = LerpVec2(last_frame->camera_pos, target_camera_pos, lerp_ratio);
+            frame->camera_zoom = LerpF32(last_frame->camera_zoom, target_camera_zoom, lerp_ratio);
         }
 
         //////////////////////////////
@@ -278,7 +281,7 @@ void V_TickForever(WaveLaneCtx *lane)
             scale.x = (f32)draw_size.x / meters_per_draw_width;
             scale.y = scale.x;
             world_to_draw_xf = XformFromScale(scale);
-            world_to_draw_xf = TranslateXform(world_to_draw_xf, NegVec2(camera_pos));
+            world_to_draw_xf = TranslateXform(world_to_draw_xf, NegVec2(frame->camera_pos));
             world_to_draw_xf = WorldTranslateXform(world_to_draw_xf, MulVec2(Vec2FromVec(draw_size), 0.5));
             draw_to_world_xf = InvertXform(world_to_draw_xf);
         }

src/pp/pp_vis/pp_vis_core.h

@@ -80,8 +80,13 @@ Struct(V_Frame)
     Arena *dvert_idxs_arena;
     G_ArenaHandle gpu_arena;
 
+    Vec2 camera_pos;
+    f32 camera_zoom;
+
     i64 tick;
     i64 time_ns;
+    i64 dt_ns;
+    f64 dt;
     G_CommandListHandle cl;
 };