Update urchin hitbox and bbox

This is so that wooden can be destroyed by urchin. Urchin can still be
crushed by a wooden crate though.

engine/collisions.c

@@ -160,7 +160,7 @@ uint8_t check_collision_at(Entity_t* p_ent, Vector2 pos, Vector2 bbox_sz, TileGr
     CollideEntity_t ent = {
         .p_ent = p_ent,
         .bbox = (Rectangle){pos.x, pos.y, bbox_sz.x, bbox_sz.y},
-        .prev_bbox = (Rectangle){pos.x, pos.y, bbox_sz.x, bbox_sz.y},
+        .prev_bbox = (Rectangle){p_ent->position.x, p_ent->position.y, bbox_sz.x, bbox_sz.y},
         .area = (TileArea_t){
             .tile_x1 = (pos.x) / grid->tile_size,
             .tile_y1 = (pos.y) / grid->tile_size,
@@ -169,7 +169,7 @@ uint8_t check_collision_at(Entity_t* p_ent, Vector2 pos, Vector2 bbox_sz, TileGr
         }
     };
     
-    return check_collision(&ent, grid, false);
+    return check_collision(&ent, grid, true);
 }
 
 bool check_on_ground(Entity_t* p_ent, Vector2 prev_pos, Vector2 bbox_sz, TileGrid_t* grid)

scenes/editor_scene.c

@@ -397,6 +397,7 @@ static void render_editor_game_scene(Scene_t* scene)
                 Color colour;
                 switch(p_ent->m_tag)
                 {
+                    case NO_ENT_TAG:
                     case PLAYER_ENT_TAG:
                         colour = RED;
                     break;
@@ -849,8 +850,11 @@ static void toggle_block_system(Scene_t* scene, ActionType_t action, bool presse
                     Entity_t* p_ent = create_urchin(&scene->ent_manager);
                     if (p_ent != NULL)
                     {
-                        p_ent->position.x = (tile_idx % tilemap.width) * tilemap.tile_size;
-                        p_ent->position.y = (tile_idx / tilemap.width) * tilemap.tile_size;
+                        CBBox_t* p_bbox = get_component(p_ent, CBBOX_COMP_T);
+                        p_ent->position.x = (tile_idx % tilemap.width) * tilemap.tile_size 
+                            + (tilemap.tile_size >> 1) - p_bbox->half_size.x;
+                        p_ent->position.y = (tile_idx / tilemap.width) * tilemap.tile_size
+                            + (tilemap.tile_size >> 1) - p_bbox->half_size.y;
                         CTransform_t* p_ct = get_component(p_ent, CTRANSFORM_COMP_T);
                         p_ct->velocity = Vector2Scale(urchin_spawn_vec, URCHIN_VELOCITY_SCALE);
                     }

scenes/game_systems.c

@@ -1,3 +1,4 @@
+#include "assets_tag.h"
 #ifdef TRACY_ENABLE
 #include "tracy/TracyC.h"
 #endif
@@ -257,6 +258,19 @@ static void destroy_entity(Scene_t* scene, TileGrid_t* tilemap, Entity_t* p_ent)
         play_particle_emitter(&scene->part_sys, &emitter);
         play_sfx(scene->engine, ARROW_DESTROY_SFX);
     }
+    else if (p_ent->m_tag == NO_ENT_TAG)
+    {
+        ParticleEmitter_t emitter = {
+            .spr = get_sprite(&scene->engine->assets, "p_spike"),
+            .config = get_emitter_conf(&scene->engine->assets, "pe_burst"),
+            .position = Vector2Add(p_ent->position, half_size),
+            .n_particles = 8,
+            .user_data = CONTAINER_OF(scene, LevelScene_t, scene),
+            .update_func = &simple_particle_system_update,
+            .emitter_update_func = NULL,
+        };
+        play_particle_emitter(&scene->part_sys, &emitter);
+    }
 
     clear_an_entity(scene, tilemap, p_ent);
 }

scenes/items_ent.c

@@ -247,11 +247,14 @@ Entity_t* create_explosion(EntityManager_t* ent_manager)
 
 Entity_t* create_urchin(EntityManager_t* ent_manager)
 {
+    // The hit box is larger than the bbox
+    // Unfortunately, it's too late to incorporate the offset for the bbox component
+    // So, offset the hitbox instead and external reposition it.
     Entity_t* p_urchin = add_entity(ent_manager, NO_ENT_TAG);
     if (p_urchin == NULL) return NULL;
 
     CBBox_t* p_bbox = add_component(p_urchin, CBBOX_COMP_T);
-    set_bbox(p_bbox, TILE_SIZE, TILE_SIZE);
+    set_bbox(p_bbox, TILE_SIZE-2, TILE_SIZE-2);
 
     CTransform_t* p_ctransform = add_component(p_urchin, CTRANSFORM_COMP_T);
     p_ctransform->movement_mode = KINEMATIC_MOVEMENT;
@@ -267,7 +270,7 @@ Entity_t* create_urchin(EntityManager_t* ent_manager)
 
     CHitBoxes_t* p_hitbox = add_component(p_urchin, CHITBOXES_T);
     p_hitbox->n_boxes = 1;
-    p_hitbox->boxes[0] = (Rectangle){3, 3, 26, 26};
+    p_hitbox->boxes[0] = (Rectangle) {-1,-1,TILE_SIZE,TILE_SIZE};
     p_hitbox->atk = 2;
 
     CSprite_t* p_cspr = add_component(p_urchin, CSPRITE_T);
@@ -287,7 +290,7 @@ Entity_t* create_chest(EntityManager_t* ent_manager)
     CBBox_t* p_bbox = add_component(p_chest, CBBOX_COMP_T);
     set_bbox(p_bbox, TILE_SIZE, TILE_SIZE);
     p_bbox->solid = true;
-    p_bbox->fragile = true;
+    p_bbox->fragile = false;
 
     CTransform_t* p_ctransform = add_component(p_chest, CTRANSFORM_COMP_T);
     p_ctransform->grav_delay = 0.3f;