From 763bd80603dbace9f14c25309159ed07ec6e9a93 Mon Sep 17 00:00:00 2001
From: Kelly Rauchenberger <fefferburbia@gmail.com>
Date: Sat, 30 Jan 2021 11:50:30 -0500
Subject: Added sprite Y sorting

---
 CMakeLists.txt   |  1 +
 src/game.cpp     | 20 ++++++++++++++++++++
 src/game.h       | 27 ++++++++++++++++++++-------
 src/party.cpp    | 10 +++++-----
 src/renderer.cpp |  2 +-
 5 files changed, 47 insertions(+), 13 deletions(-)
 create mode 100644 src/game.cpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3b46e02..4bbc297 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -30,6 +30,7 @@ add_executable(tanetane
   src/renderer.cpp
   src/sprite.cpp
   src/party.cpp
+  src/game.cpp
 )
 
 set_property(TARGET tanetane PROPERTY CXX_STANDARD 17)
diff --git a/src/game.cpp b/src/game.cpp
new file mode 100644
index 0000000..ccca10f
--- /dev/null
+++ b/src/game.cpp
@@ -0,0 +1,20 @@
+#include "game.h"
+
+int Game::addSprite(Sprite sprite) {
+  int id = sprites_.size();
+  sprites_.push_back(std::move(sprite));
+  spritesByY_.emplace(sprite.loc().y(), id);
+  return id;
+}
+
+void Game::moveSprite(int id, vec2i newLoc) {
+  Sprite& sprite = sprites_.at(id);
+  bool changedY = (sprite.loc().y() != newLoc.y());
+  if (changedY) {
+    spritesByY_.erase(std::make_tuple(sprite.loc().y(), id));
+  }
+  sprite.loc() = newLoc;
+  if (changedY) {
+    spritesByY_.emplace(newLoc.y(), id);
+  }
+}
\ No newline at end of file
diff --git a/src/game.h b/src/game.h
index bb99543..abb70ce 100644
--- a/src/game.h
+++ b/src/game.h
@@ -1,6 +1,8 @@
 #ifndef GAME_H_E6F1396E
 #define GAME_H_E6F1396E
 
+#include <set>
+#include <range/v3/all.hpp>
 #include <vector>
 #include "sprite.h"
 
@@ -14,23 +16,34 @@ struct Input {
 class Game {
 public:
 
-  int addSprite(Sprite sprite) {
-    int id = sprites_.size();
-    sprites_.push_back(std::move(sprite));
-    return id;
-  }
+  int addSprite(Sprite sprite);
 
-  Sprite& getSprite(int id) {
+  const Sprite& getSprite(int id) const {
     return sprites_.at(id);
   }
 
-  std::vector<Sprite>& getSprites() {
+  const std::vector<Sprite>& getSprites() {
     return sprites_;
   }
 
+  auto spriteView() const {
+    return ranges::views::transform([&] (int id) -> const Sprite& {
+      return sprites_.at(id);
+    });
+  }
+
+  auto getSpritesByY() const {
+    return spritesByY_ | ranges::views::transform([] (const std::tuple<int, int>& val) {
+      return std::get<1>(val);
+    });
+  }
+
+  void moveSprite(int id, vec2i newLoc);
+
 private:
 
   std::vector<Sprite> sprites_;
+  std::set<std::tuple<int, int>> spritesByY_;
 };
 
 #endif /* end of include guard: GAME_H_E6F1396E */
diff --git a/src/party.cpp b/src/party.cpp
index 6c003b8..1ff4bb4 100644
--- a/src/party.cpp
+++ b/src/party.cpp
@@ -8,7 +8,7 @@ void Party::addMember(Game& game, int spriteId) {
   newMember.spriteId = spriteId;
 
   if (index > 0) {
-    Sprite& sprite = game.getSprite(spriteId);
+    const Sprite& sprite = game.getSprite(spriteId);
 
     for (int i = 0; i < PARTY_FRAME_DELAY * index; i++) {
       newMember.nextPosition.push_back(sprite.loc());
@@ -23,7 +23,7 @@ void Party::move(Game& game, const Input& keystate) {
     return;
   }
 
-  Sprite& p1 = game.getSprite(members_[0].spriteId);
+  const Sprite& p1 = game.getSprite(members_[0].spriteId);
   vec2i pLoc = p1.loc();
 
   if (keystate.up)
@@ -47,12 +47,12 @@ void Party::move(Game& game, const Input& keystate) {
   }
 
   if (keystate.up || keystate.down || keystate.left || keystate.right) {
-    p1.loc() = pLoc;
+    game.moveSprite(members_[0].spriteId, pLoc);
 
     for (int i = 1; i < members_.size(); i++) {
-      Sprite& pNext = game.getSprite(members_[i].spriteId);
+      const Sprite& pNext = game.getSprite(members_[i].spriteId);
       members_[i].nextPosition.push_back(pLoc);
-      pNext.loc() = members_[i].nextPosition.front();
+      game.moveSprite(members_[i].spriteId, members_[i].nextPosition.front());
       members_[i].nextPosition.pop_front();
     }
   }
diff --git a/src/renderer.cpp b/src/renderer.cpp
index bcc3e95..8053de0 100644
--- a/src/renderer.cpp
+++ b/src/renderer.cpp
@@ -48,7 +48,7 @@ void Renderer::render(Game& game) {
   SDL_SetRenderDrawColor(ren_.get(), 255, 255, 255, 255);
   SDL_RenderClear(ren_.get());
 
-  for (Sprite& sprite : game.getSprites()) {
+  for (const Sprite& sprite : game.getSpritesByY() | game.spriteView()) {
     SDL_Rect dest { sprite.loc().x(), sprite.loc().y(), sprite.size().w(), sprite.size().h() };
     SDL_RenderCopy(ren_.get(), textures_.at(sprite.getTextureId()).get(), nullptr, &dest);
   }
-- 
cgit 1.4.1