Fix issues with unisolid tiles and frozen enemies (#2933)

* Do not let unisolid tiles prevent Tux from stand up

* Consider Tux being on ground if standing on frozen enemy

* Do not change direction of bouncing snowballs due to unisolid tile

* Change PushButton collision goup to static

* Do not change vicious ivy's floating animation when passing a unisolid from below

Author: Brockengespenst

src/badguy/bouncing_snowball.cpp

@@ -82,7 +82,7 @@ BouncingSnowball::active_update(float dt_sec)
   Rectf side_look_box = get_bbox().grown(-1.f);
   side_look_box.set_left(get_bbox().get_left() + (m_dir == Direction::LEFT ? -1.f : 1.f));
   side_look_box.set_right(get_bbox().get_right() + (m_dir == Direction::LEFT ? -1.f : 1.f));
-  if (!Sector::get().is_free_of_statics(side_look_box))
+  if (!Sector::get().is_free_of_statics(side_look_box, nullptr, true))
   {
     m_dir = m_dir == Direction::LEFT ? Direction::RIGHT : Direction::LEFT;
     set_action(m_dir);

src/badguy/viciousivy.cpp

@@ -92,7 +92,9 @@ ViciousIvy::active_update(float dt_sec)
   {
     Rectf floatbox = get_bbox();
     floatbox.set_bottom(get_bbox().get_bottom() + 8.f);
-    bool float_here = (Sector::get().is_free_of_statics(floatbox));
+
+    const bool ignore_unisolid = m_physic.get_velocity_y() < 0.0f;
+    bool float_here = (Sector::get().is_free_of_statics(floatbox, nullptr, ignore_unisolid));
 
     bool in_water = !Sector::get().is_free_of_tiles(get_bbox(), true, Tile::WATER);
 

src/collision/collision_system.cpp

@@ -726,11 +726,11 @@ CollisionSystem::is_free_of_statics(const Rectf& rect, const CollisionObject* ig
 }
 
 bool
-CollisionSystem::is_free_of_movingstatics(const Rectf& rect, const CollisionObject* ignore_object) const
+CollisionSystem::is_free_of_movingstatics(const Rectf& rect, const CollisionObject* ignore_object, const bool ignore_unisolid) const
 {
   using namespace collision;
 
-  if (!is_free_of_tiles(rect)) return false;
+  if (!is_free_of_tiles(rect, ignore_unisolid)) return false;
 
   for (const auto& object : m_objects) {
     if (object == ignore_object) continue;

src/collision/collision_system.hpp

@@ -64,7 +64,7 @@ class CollisionSystem final
 
   bool is_free_of_tiles(const Rectf& rect, const bool ignoreUnisolid = false, uint32_t tiletype = Tile::SOLID) const;
   bool is_free_of_statics(const Rectf& rect, const CollisionObject* ignore_object, const bool ignoreUnisolid, uint32_t tiletype = Tile::SOLID) const;
-  bool is_free_of_movingstatics(const Rectf& rect, const CollisionObject* ignore_object) const;
+  bool is_free_of_movingstatics(const Rectf& rect, const CollisionObject* ignore_object, const bool ignore_unisolid = false) const;
   bool is_free_of_specifically_movingstatics(const Rectf& rect, const CollisionObject* ignore_object) const;
 
   enum RaycastIgnore {

src/object/player.cpp

@@ -1353,7 +1353,7 @@ Player::do_standup(bool force_standup)
   float new_height = m_swimming ? TUX_WIDTH : BIG_TUX_HEIGHT;
   new_bbox.move(Vector(0, m_col.m_bbox.get_height() - new_height));
   new_bbox.set_height(new_height);
-  if (!Sector::get().is_free_of_movingstatics(new_bbox, this) && !force_standup)
+  if (!Sector::get().is_free_of_movingstatics(new_bbox, this, true) && !force_standup)
   {
     m_crawl = true;
     return;
@@ -2392,6 +2392,9 @@ Player::collision(MovingObject& other, const CollisionHit& hit)
       return FORCE_MOVE;
     if (m_stone)
       return ABORT_MOVE;
+
+    if (hit.bottom && badguy->is_frozen())
+      m_on_ground_flag = true;
   }
 
   return CONTINUE;

src/object/pushbutton.cpp

@@ -31,7 +31,7 @@ const std::string BUTTON_SOUND = "sounds/switch.ogg";
 }
 
 PushButton::PushButton(const ReaderMapping& mapping) :
-  StickyObject(mapping, "images/objects/pushbutton/pushbutton.sprite", LAYER_BACKGROUNDTILES+1, COLGROUP_MOVING),
+  StickyObject(mapping, "images/objects/pushbutton/pushbutton.sprite", LAYER_BACKGROUNDTILES+1, COLGROUP_STATIC),
   m_script(),
   m_state(OFF),
   m_dir(Direction::UP)

src/supertux/sector.cpp

@@ -551,10 +551,11 @@ Sector::is_free_of_statics(float left, float top, float right, float bottom,
 }
 
 bool
-Sector::is_free_of_movingstatics(const Rectf& rect, const MovingObject* ignore_object) const
+Sector::is_free_of_movingstatics(const Rectf& rect, const MovingObject* ignore_object, bool ignore_unisolid) const
 {
   return m_collision_system->is_free_of_movingstatics(rect,
-                                                      ignore_object ? ignore_object->get_collision_object() : nullptr);
+                                                      ignore_object ? ignore_object->get_collision_object() : nullptr,
+                                                      ignore_unisolid);
 }
 
 bool

src/supertux/sector.hpp

@@ -149,7 +149,8 @@ class Sector final : public Base::Sector
       1.) solid tiles and
       2.) MovingObjects in COLGROUP_STATIC, COLGROUP_MOVINGSTATIC or COLGROUP_MOVING.
       This includes badguys and players. */
-  bool is_free_of_movingstatics(const Rectf& rect, const MovingObject* ignore_object = nullptr) const;
+  bool is_free_of_movingstatics(const Rectf& rect, const MovingObject* ignore_object = nullptr,
+                                bool ignore_unisolid = false) const;
   /**
    * @scripting
    * @description Checks if the specified sector-relative rectangle is free of both: