From b628c80f988c1fb250b94b17dca8e082bc4c1d0b Mon Sep 17 00:00:00 2001
From: Kelly Rauchenberger <fefferburbia@gmail.com>
Date: Tue, 2 Feb 2021 16:51:22 -0500
Subject: Added moving camera

---
 src/game.cpp     | 24 +++++++++++++++++++++++-
 src/game.h       | 21 +++++++++++++++++++++
 src/main.cpp     |  6 ++++++
 src/renderer.cpp | 27 ++++++++++++++-------------
 src/vector.h     |  2 ++
 5 files changed, 66 insertions(+), 14 deletions(-)

diff --git a/src/game.cpp b/src/game.cpp
index ccca10f..ebb792e 100644
--- a/src/game.cpp
+++ b/src/game.cpp
@@ -17,4 +17,26 @@ void Game::moveSprite(int id, vec2i newLoc) {
   if (changedY) {
     spritesByY_.emplace(newLoc.y(), id);
   }
-}
\ No newline at end of file
+}
+
+void Game::tick() {
+  if (!cameraLocked_) {
+    const Sprite& follow = getSprite(followingSprite_);
+    vec2i mapBounds = map_->getMapSize() * map_->getTileSize();
+
+    cameraPos_ = follow.loc() - (cameraFov_ / 2);
+
+    if (cameraPos_.x() < 0) {
+      cameraPos_.x() = 0;
+    }
+    if (cameraPos_.y() < 0) {
+      cameraPos_.y() = 0;
+    }
+    if (cameraPos_.x() + cameraFov_.w() >= mapBounds.w()) {
+      cameraPos_.x() = mapBounds.w() - cameraFov_.w() - 1;
+    }
+    if (cameraPos_.y() + cameraFov_.h() >= mapBounds.h()) {
+      cameraPos_.y() = mapBounds.h() - cameraFov_.h() - 1;
+    }
+  }
+}
diff --git a/src/game.h b/src/game.h
index 2c1680a..a717d53 100644
--- a/src/game.h
+++ b/src/game.h
@@ -7,6 +7,7 @@
 #include <memory>
 #include "sprite.h"
 #include "map.h"
+#include "consts.h"
 
 struct Input {
   bool left = false;
@@ -60,11 +61,31 @@ public:
 
   const Map& getMap() const { return *map_; }
 
+  // Camera
+
+  const vec2i& getCameraPosition() const { return cameraPos_; }
+
+  const vec2i& getFieldOfView() const { return cameraFov_; }
+
+  void setFollowingSprite(int spriteId) { followingSprite_ = spriteId; }
+
+  void lockCamera() { cameraLocked_ = true; }
+
+  void unlockCamera() { cameraLocked_ = false; }
+
+  void tick();
+
 private:
 
   std::vector<Sprite> sprites_;
   std::set<std::tuple<int, int>> spritesByY_;
   std::unique_ptr<Map> map_;
+
+  // Camera
+  vec2i cameraPos_;
+  vec2i cameraFov_ { CANVAS_WIDTH, CANVAS_HEIGHT };
+  int followingSprite_;
+  bool cameraLocked_ = true;
 };
 
 #endif /* end of include guard: GAME_H_E6F1396E */
diff --git a/src/main.cpp b/src/main.cpp
index 587ae15..b3aee1a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -26,6 +26,10 @@ void loop(Renderer& renderer) {
   party.addMember(game, dusterSprite);
   party.addMember(game, boneySprite);
 
+  game.setFollowingSprite(lucasSprite);
+  game.unlockCamera();
+  game.tick();
+
   renderer.render(game);
 
   Timer inputTimer(50);
@@ -65,6 +69,8 @@ void loop(Renderer& renderer) {
       game.tickSpriteAnim();
     }
 
+    game.tick();
+
     renderer.render(game);
   }
 }
diff --git a/src/renderer.cpp b/src/renderer.cpp
index 9d20fee..03d5173 100644
--- a/src/renderer.cpp
+++ b/src/renderer.cpp
@@ -88,13 +88,15 @@ void Renderer::render(Game& game) {
     renLay0_ = renderMapLayer(game.getMap(), 1);
   }
 
+  vec2i mapBounds = game.getMap().getMapSize() * game.getMap().getTileSize();
+
   texture_ptr canvas(
     SDL_CreateTexture(
       ren_.get(),
       SDL_PIXELFORMAT_RGBA8888,
       SDL_TEXTUREACCESS_TARGET,
-      CANVAS_WIDTH,
-      CANVAS_HEIGHT));
+      mapBounds.w(),
+      mapBounds.h()));
 
   if (!canvas) {
     throw sdl_error();
@@ -105,12 +107,7 @@ void Renderer::render(Game& game) {
   SDL_SetRenderDrawColor(ren_.get(), 255, 255, 255, 255);
   SDL_RenderClear(ren_.get());
 
-  vec2i mapBounds = game.getMap().getMapSize() * game.getMap().getTileSize();
-
-  {
-    SDL_Rect dest { -80, -80, mapBounds.w(), mapBounds.h() };
-    SDL_RenderCopy(ren_.get(), renLay1_.get(), nullptr, &dest);
-  }
+  SDL_RenderCopy(ren_.get(), renLay1_.get(), nullptr, nullptr);
 
   for (const Sprite& sprite : game.getSpritesByY() | game.spriteView()) {
     const SpriteFrame& frame = sprite.getFrame();
@@ -119,13 +116,17 @@ void Renderer::render(Game& game) {
     SDL_RenderCopy(ren_.get(), textures_.at(sprite.getTextureId()).get(), &src, &dest);
   }
 
-  {
-    SDL_Rect dest { -80, -80, mapBounds.w(), mapBounds.h() };
-    SDL_RenderCopy(ren_.get(), renLay0_.get(), nullptr, &dest);
-  }
+  SDL_RenderCopy(ren_.get(), renLay0_.get(), nullptr, nullptr);
+
+  SDL_Rect cameraField {
+    game.getCameraPosition().x(),
+    game.getCameraPosition().y(),
+    game.getFieldOfView().w(),
+    game.getFieldOfView().h()
+  };
 
   SDL_SetRenderTarget(ren_.get(), nullptr);
-  SDL_RenderCopy(ren_.get(), canvas.get(), nullptr, nullptr);
+  SDL_RenderCopy(ren_.get(), canvas.get(), &cameraField, nullptr);
   SDL_RenderPresent(ren_.get());
 }
 
diff --git a/src/vector.h b/src/vector.h
index d54fdbb..8019edf 100644
--- a/src/vector.h
+++ b/src/vector.h
@@ -1,6 +1,8 @@
 #ifndef VECTOR_H_5458ED71
 #define VECTOR_H_5458ED71
 
+#include <tuple>
+
 template <typename T>
 class vec2 {
 public:
-- 
cgit 1.4.1