Very basic ECS

14 files changed, 1063 insertions, 0 deletions

@@ -0,0 +1 @@
+build
@@ -0,0 +1,30 @@
+cmake_minimum_required (VERSION 3.1)
+project (dispatcher)
+
+# Set directory to look for package helpers.
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${dispatcher_SOURCE_DIR}/cmake")
+
+find_package(SDL2 REQUIRED)
+find_package(SDL2_Image REQUIRED)
+
+set(ALL_LIBS
+  ${SDL2_LIBRARY}
+  ${SDL2_IMAGE_LIBRARIES}
+)
+
+include_directories(
+  ${SDL2_INCLUDE_DIR}
+  ${SDL2_IMAGE_INCLUDE_DIRS}
+  src
+  vendor
+)
+
+add_executable(dispatcher
+  src/main.cpp
+  src/renderer.cpp
+  src/simulation.cpp
+)
+
+set_property(TARGET dispatcher PROPERTY CXX_STANDARD 17)
+set_property(TARGET dispatcher PROPERTY CXX_STANDARD_REQUIRED ON)
+target_link_libraries(dispatcher ${ALL_LIBS})
@@ -0,0 +1,254 @@
+# Locate SDL2 library
+# This module defines
+# SDL2_LIBRARY, the name of the library to link against
+# SDL2_FOUND, if false, do not try to link to SDL2
+# SDL2_INCLUDE_DIR, where to find SDL.h
+#
+# This module responds to the the flag:
+# SDL2_BUILDING_LIBRARY
+# If this is defined, then no SDL2_main will be linked in because
+# only applications need main().
+# Otherwise, it is assumed you are building an application and this
+# module will attempt to locate and set the the proper link flags
+# as part of the returned SDL2_LIBRARY variable.
+#
+# Don't forget to include SDL2main.h and SDL2main.m your project for the
+# OS X framework based version. (Other versions link to -lSDL2main which
+# this module will try to find on your behalf.) Also for OS X, this
+# module will automatically add the -framework Cocoa on your behalf.
+#
+#
+# Additional Note: If you see an empty SDL2_LIBRARY_TEMP in your configuration
+# and no SDL2_LIBRARY, it means CMake did not find your SDL2 library
+# (SDL2.dll, libsdl2.so, SDL2.framework, etc).
+# Set SDL2_LIBRARY_TEMP to point to your SDL2 library, and configure again.
+# Similarly, if you see an empty SDL2MAIN_LIBRARY, you should set this value
+# as appropriate. These values are used to generate the final SDL2_LIBRARY
+# variable, but when these values are unset, SDL2_LIBRARY does not get created.
+#
+#
+# $SDL2 is an environment variable that would
+# correspond to the ./configure --prefix=$SDL2
+# used in building SDL2.
+# l.e.galup 9-20-02
+#
+# Modified by Eric Wing.
+# Added code to assist with automated building by using environmental variables
+# and providing a more controlled/consistent search behavior.
+# Added new modifications to recognize OS X frameworks and
+# additional Unix paths (FreeBSD, etc).
+# Also corrected the header search path to follow "proper" SDL2 guidelines.
+# Added a search for SDL2main which is needed by some platforms.
+# Added a search for threads which is needed by some platforms.
+# Added needed compile switches for MinGW.
+#
+# On OSX, this will prefer the Framework version (if found) over others.
+# People will have to manually change the cache values of
+# SDL2_LIBRARY to override this selection or set the CMake environment
+# CMAKE_INCLUDE_PATH to modify the search paths.
+#
+# Note that the header path has changed from SDL2/SDL.h to just SDL.h
+# This needed to change because "proper" SDL2 convention
+# is #include "SDL.h", not <SDL2/SDL.h>. This is done for portability
+# reasons because not all systems place things in SDL2/ (see FreeBSD).
+#
+# Ported by Johnny Patterson. This is a literal port for SDL2 of the FindSDL.cmake
+# module with the minor edit of changing "SDL" to "SDL2" where necessary. This
+# was not created for redistribution, and exists temporarily pending official
+# SDL2 CMake modules.
+#
+# Note that on windows this will only search for the 32bit libraries, to search
+# for 64bit change x86/i686-w64 to x64/x86_64-w64
+
+#=============================================================================
+# Copyright 2003-2009 Kitware, Inc.
+#
+# CMake - Cross Platform Makefile Generator
+# Copyright 2000-2014 Kitware, Inc.
+# Copyright 2000-2011 Insight Software Consortium
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution.
+#
+# * Neither the names of Kitware, Inc., the Insight Software Consortium,
+# nor the names of their contributors may be used to endorse or promote
+# products derived from this software without specific prior written
+# permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the License for more information.
+#=============================================================================
+# (To distribute this file outside of CMake, substitute the full
+# License text for the above reference.)
+
+FIND_PATH(SDL2_INCLUDE_DIR SDL.h
+        HINTS
+        ${SDL2}
+        $ENV{SDL2}
+        PATH_SUFFIXES include/SDL2 include SDL2
+        i686-w64-mingw32/include/SDL2
+        x86_64-w64-mingw32/include/SDL2
+        PATHS
+        ~/Library/Frameworks
+        /Library/Frameworks
+        /usr/local/include/SDL2
+        /usr/include/SDL2
+        /sw # Fink
+        /opt/local # DarwinPorts
+        /opt/csw # Blastwave
+        /opt
+)
+
+# Lookup the 64 bit libs on x64
+IF(CMAKE_SIZEOF_VOID_P EQUAL 8)
+        FIND_LIBRARY(SDL2_LIBRARY_TEMP SDL2
+                HINTS
+                ${SDL2}
+                $ENV{SDL2}
+                PATH_SUFFIXES lib64 lib
+                lib/x64
+                x86_64-w64-mingw32/lib
+                PATHS
+                /sw
+                /opt/local
+                /opt/csw
+                /opt
+        )
+# On 32bit build find the 32bit libs
+ELSE(CMAKE_SIZEOF_VOID_P EQUAL 8)
+        FIND_LIBRARY(SDL2_LIBRARY_TEMP SDL2
+                HINTS
+                ${SDL2}
+                $ENV{SDL2}
+                PATH_SUFFIXES lib
+                lib/x86
+                i686-w64-mingw32/lib
+                PATHS
+                /sw
+                /opt/local
+                /opt/csw
+                /opt
+        )
+ENDIF(CMAKE_SIZEOF_VOID_P EQUAL 8)
+
+IF(NOT SDL2_BUILDING_LIBRARY)
+        IF(NOT ${SDL2_INCLUDE_DIR} MATCHES ".framework")
+                # Non-OS X framework versions expect you to also dynamically link to
+                # SDL2main. This is mainly for Windows and OS X. Other (Unix) platforms
+                # seem to provide SDL2main for compatibility even though they don't
+                # necessarily need it.
+                # Lookup the 64 bit libs on x64
+                IF(CMAKE_SIZEOF_VOID_P EQUAL 8)
+                        FIND_LIBRARY(SDL2MAIN_LIBRARY
+                                NAMES SDL2main
+                                HINTS
+                                ${SDL2}
+                                $ENV{SDL2}
+                                PATH_SUFFIXES lib64 lib
+                                lib/x64
+                                x86_64-w64-mingw32/lib
+                                PATHS
+                                /sw
+                                /opt/local
+                                /opt/csw
+                                /opt
+                                )
+                        # On 32bit build find the 32bit libs
+                ELSE(CMAKE_SIZEOF_VOID_P EQUAL 8)
+                        FIND_LIBRARY(SDL2MAIN_LIBRARY
+                                NAMES SDL2main
+                                HINTS
+                                ${SDL2}
+                                $ENV{SDL2}
+                                PATH_SUFFIXES lib
+                                lib/x86
+                                i686-w64-mingw32/lib
+                                PATHS
+                                /sw
+                                /opt/local
+                                /opt/csw
+                                /opt
+                                )
+                ENDIF(CMAKE_SIZEOF_VOID_P EQUAL 8)
+        ENDIF(NOT ${SDL2_INCLUDE_DIR} MATCHES ".framework")
+ENDIF(NOT SDL2_BUILDING_LIBRARY)
+
+# SDL2 may require threads on your system.
+# The Apple build may not need an explicit flag because one of the
+# frameworks may already provide it.
+# But for non-OSX systems, I will use the CMake Threads package.
+IF(NOT APPLE)
+        FIND_PACKAGE(Threads)
+ENDIF(NOT APPLE)
+
+# MinGW needs an additional library, mwindows
+# It's total link flags should look like -lmingw32 -lSDL2main -lSDL2 -lmwindows
+# (Actually on second look, I think it only needs one of the m* libraries.)
+IF(MINGW)
+        SET(MINGW32_LIBRARY mingw32 CACHE STRING "mwindows for MinGW")
+ENDIF(MINGW)
+
+SET(SDL2_FOUND "NO")
+        IF(SDL2_LIBRARY_TEMP)
+                # For SDL2main
+                IF(NOT SDL2_BUILDING_LIBRARY)
+                        IF(SDL2MAIN_LIBRARY)
+                                SET(SDL2_LIBRARY_TEMP ${SDL2MAIN_LIBRARY} ${SDL2_LIBRARY_TEMP})
+                        ENDIF(SDL2MAIN_LIBRARY)
+                ENDIF(NOT SDL2_BUILDING_LIBRARY)
+
+                # For OS X, SDL2 uses Cocoa as a backend so it must link to Cocoa.
+                # CMake doesn't display the -framework Cocoa string in the UI even
+                # though it actually is there if I modify a pre-used variable.
+                # I think it has something to do with the CACHE STRING.
+                # So I use a temporary variable until the end so I can set the
+                # "real" variable in one-shot.
+                IF(APPLE)
+                        SET(SDL2_LIBRARY_TEMP ${SDL2_LIBRARY_TEMP} "-framework Cocoa")
+                ENDIF(APPLE)
+
+                # For threads, as mentioned Apple doesn't need this.
+                # In fact, there seems to be a problem if I used the Threads package
+                # and try using this line, so I'm just skipping it entirely for OS X.
+                IF(NOT APPLE)
+                        SET(SDL2_LIBRARY_TEMP ${SDL2_LIBRARY_TEMP} ${CMAKE_THREAD_LIBS_INIT})
+                ENDIF(NOT APPLE)
+
+                # For MinGW library
+                IF(MINGW)
+                        SET(SDL2_LIBRARY_TEMP ${MINGW32_LIBRARY} ${SDL2_LIBRARY_TEMP})
+                ENDIF(MINGW)
+
+                # Set the final string here so the GUI reflects the final state.
+                SET(SDL2_LIBRARY ${SDL2_LIBRARY_TEMP} CACHE STRING "Where the SDL2 Library can be found")
+                # Set the temp variable to INTERNAL so it is not seen in the CMake GUI
+                SET(SDL2_LIBRARY_TEMP "${SDL2_LIBRARY_TEMP}" CACHE INTERNAL "")
+
+                SET(SDL2_FOUND "YES")
+ENDIF(SDL2_LIBRARY_TEMP)
+
+INCLUDE(FindPackageHandleStandardArgs)
+
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(SDL2 REQUIRED_VARS SDL2_LIBRARY SDL2_INCLUDE_DIR)
@@ -0,0 +1,98 @@
+# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
+
+#.rst:
+# FindSDL2_image
+# -------------
+#
+# Locate SDL2_image library
+#
+# This module defines:
+#
+# ::
+#
+# SDL2_IMAGE_LIBRARIES, the name of the library to link against
+# SDL2_IMAGE_INCLUDE_DIRS, where to find the headers
+# SDL2_IMAGE_FOUND, if false, do not try to link against
+# SDL2_IMAGE_VERSION_STRING - human-readable string containing the
+# version of SDL_image
+#
+#
+#
+# For backward compatibility the following variables are also set:
+#
+# ::
+#
+# SDL2IMAGE_LIBRARY (same value as SDL_IMAGE_LIBRARIES)
+# SDL2IMAGE_INCLUDE_DIR (same value as SDL_IMAGE_INCLUDE_DIRS)
+# SDL2IMAGE_FOUND (same value as SDL_IMAGE_FOUND)
+#
+#
+#
+# $SDL2DIR is an environment variable that would correspond to the
+# ./configure --prefix=$SDL2DIR used in building SDL.
+#
+# Created by Eric Wing. This was influenced by the FindSDL.cmake
+# module, but with modifications to recognize OS X frameworks and
+# additional Unix paths (FreeBSD, etc).
+
+if(NOT SDL2_IMAGE_INCLUDE_DIR AND SDL2IMAGE_INCLUDE_DIR)
+  set(SDL2_IMAGE_INCLUDE_DIR ${SDL2IMAGE_INCLUDE_DIR} CACHE PATH "directory cache entry initialized from old variable name")
+endif()
+find_path(SDL2_IMAGE_INCLUDE_DIR SDL_image.h
+  HINTS
+    ENV SDL2IMAGEDIR
+    ENV SDL2DIR
+    ${SDL2_DIR}
+  PATH_SUFFIXES SDL2
+                # path suffixes to search inside ENV{SDL2DIR}
+                include/SDL2 include
+)
+
+if(CMAKE_SIZEOF_VOID_P EQUAL 8)
+  set(VC_LIB_PATH_SUFFIX lib/x64)
+else()
+  set(VC_LIB_PATH_SUFFIX lib/x86)
+endif()
+
+if(NOT SDL2_IMAGE_LIBRARY AND SDL2IMAGE_LIBRARY)
+  set(SDL2_IMAGE_LIBRARY ${SDL2IMAGE_LIBRARY} CACHE FILEPATH "file cache entry initialized from old variable name")
+endif()
+find_library(SDL2_IMAGE_LIBRARY
+  NAMES SDL2_image
+  HINTS
+    ENV SDL2IMAGEDIR
+    ENV SDL2DIR
+    ${SDL2_DIR}
+  PATH_SUFFIXES lib ${VC_LIB_PATH_SUFFIX}
+)
+
+if(SDL2_IMAGE_INCLUDE_DIR AND EXISTS "${SDL2_IMAGE_INCLUDE_DIR}/SDL_image.h")
+  file(STRINGS "${SDL2_IMAGE_INCLUDE_DIR}/SDL_image.h" SDL2_IMAGE_VERSION_MAJOR_LINE REGEX "^#define[ \t]+SDL_IMAGE_MAJOR_VERSION[ \t]+[0-9]+$")
+  file(STRINGS "${SDL2_IMAGE_INCLUDE_DIR}/SDL_image.h" SDL2_IMAGE_VERSION_MINOR_LINE REGEX "^#define[ \t]+SDL_IMAGE_MINOR_VERSION[ \t]+[0-9]+$")
+  file(STRINGS "${SDL2_IMAGE_INCLUDE_DIR}/SDL_image.h" SDL2_IMAGE_VERSION_PATCH_LINE REGEX "^#define[ \t]+SDL_IMAGE_PATCHLEVEL[ \t]+[0-9]+$")
+  string(REGEX REPLACE "^#define[ \t]+SDL_IMAGE_MAJOR_VERSION[ \t]+([0-9]+)$" "\\1" SDL2_IMAGE_VERSION_MAJOR "${SDL_IMAGE_VERSION_MAJOR_LINE}")
+  string(REGEX REPLACE "^#define[ \t]+SDL_IMAGE_MINOR_VERSION[ \t]+([0-9]+)$" "\\1" SDL2_IMAGE_VERSION_MINOR "${SDL_IMAGE_VERSION_MINOR_LINE}")
+  string(REGEX REPLACE "^#define[ \t]+SDL_IMAGE_PATCHLEVEL[ \t]+([0-9]+)$" "\\1" SDL2_IMAGE_VERSION_PATCH "${SDL_IMAGE_VERSION_PATCH_LINE}")
+  set(SDL2_IMAGE_VERSION_STRING ${SDL2_IMAGE_VERSION_MAJOR}.${SDL2_IMAGE_VERSION_MINOR}.${SDL2_IMAGE_VERSION_PATCH})
+  unset(SDL2_IMAGE_VERSION_MAJOR_LINE)
+  unset(SDL2_IMAGE_VERSION_MINOR_LINE)
+  unset(SDL2_IMAGE_VERSION_PATCH_LINE)
+  unset(SDL2_IMAGE_VERSION_MAJOR)
+  unset(SDL2_IMAGE_VERSION_MINOR)
+  unset(SDL2_IMAGE_VERSION_PATCH)
+endif()
+
+set(SDL2_IMAGE_LIBRARIES ${SDL2_IMAGE_LIBRARY})
+set(SDL2_IMAGE_INCLUDE_DIRS ${SDL2_IMAGE_INCLUDE_DIR})
+
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(SDL2_image
+                                  REQUIRED_VARS SDL2_IMAGE_LIBRARIES SDL2_IMAGE_INCLUDE_DIRS
+                                  VERSION_VAR SDL2_IMAGE_VERSION_STRING)
+
+# for backward compatibility
+set(SDL2IMAGE_LIBRARY ${SDL2_IMAGE_LIBRARIES})
+set(SDL2IMAGE_INCLUDE_DIR ${SDL2_IMAGE_INCLUDE_DIRS})
+set(SDL2IMAGE_FOUND ${SDL2_IMAGE_FOUND})
+
+mark_as_advanced(SDL2_IMAGE_LIBRARY SDL2_IMAGE_INCLUDE_DIR)
@@ -0,0 +1,10 @@
+#ifndef CONSTS_H_8019F1B3
+#define CONSTS_H_8019F1B3
+
+#include "vector.h"
+
+constexpr vec2s TILE_SIZE { 32, 32 };
+constexpr vec2s LEVEL_SIZE { 16, 16 };
+constexpr vec2s WINDOW_SIZE = TILE_SIZE * LEVEL_SIZE;
+
+#endif /* end of include guard: CONSTS_H_8019F1B3 */
@@ -0,0 +1,31 @@
+#ifndef ENTITY_H_0D6CB29A
+#define ENTITY_H_0D6CB29A
+
+#include "vector.h"
+
+class Entity {
+public:
+
+  // Transform
+  vec2s pos;
+  vec2s size;
+
+  // Grid placement
+  vec2s gridPos;
+
+  // Movement
+  bool moving = false;
+  vec2s destPos;
+  double movementTween = 0.0;
+  double speed = 0.0; // Tiles per second
+
+  // Player
+  bool player = false;
+
+  // Collision
+  bool playerCanPush = false;
+  bool trainCanPush = false;
+
+};
+
+#endif /* end of include guard: ENTITY_H_0D6CB29A */
@@ -0,0 +1,52 @@
+#ifndef LEVEL_H_678CFCCF
+#define LEVEL_H_678CFCCF
+
+#include "consts.h"
+#include "tileset.h"
+
+class Level {
+public:
+
+  Level()
+  {
+    size_ = LEVEL_SIZE;
+
+    tiles_.resize(size_.w() * size_.h());
+
+    for (size_t y = 0; y < size_.h(); y++)
+    {
+      for (size_t x = 0; x < size_.w(); x++)
+      {
+        tiles_[x+y*size_.w()] = rand() % 10;
+      }
+    }
+  }
+
+  const vec2s& getSize() const
+  {
+    return size_;
+  }
+
+  size_t at(vec2s pos) const
+  {
+    return at(pos.x(), pos.y());
+  }
+
+  size_t at(size_t x, size_t y) const
+  {
+    return tiles_.at(x + size_.w() * y);
+  }
+
+  const Tileset& getTileset() const
+  {
+    return tileset_;
+  }
+
+private:
+
+  vec2s size_;
+  std::vector<size_t> tiles_;
+  Tileset tileset_;
+};
+
+#endif /* end of include guard: LEVEL_H_678CFCCF */
@@ -0,0 +1,60 @@
+#include "renderer.h"
+
+#include <random>
+#include "simulation.h"
+#include "level.h"
+
+int main(int, char**)
+{
+  std::random_device randomEngine;
+  std::mt19937 rng(randomEngine());
+
+  Renderer renderer;
+  Level level;
+  Simulation sim(level);
+
+  Simulation::id_type player = sim.emplaceEntity();
+  Entity& entity = sim.getEntity(player);
+  entity.gridPos.x() = 1;
+  entity.gridPos.y() = 5;
+  entity.size = TILE_SIZE;
+  entity.speed = 3.0;
+  entity.player = true;
+
+  bool quit = false;
+
+  SDL_Event e;
+  size_t lastTime = SDL_GetTicks();
+
+  while (!quit)
+  {
+    size_t currentTime = SDL_GetTicks();
+    size_t frameTime = currentTime - lastTime;
+    lastTime = currentTime;
+
+    while (SDL_PollEvent(&e))
+    {
+      if (e.type == SDL_QUIT)
+      {
+        quit = true;
+      } else if (e.type == SDL_KEYDOWN)
+      {
+        switch (e.key.keysym.sym)
+        {
+          case SDLK_ESCAPE:
+          {
+            quit = true;
+
+            break;
+          }
+        }
+      }
+    }
+
+    const Uint8* state = SDL_GetKeyboardState(NULL);
+
+    sim.tick(frameTime / 1000.0, state);
+
+    renderer.render(sim);
+  }
+}
@@ -0,0 +1,97 @@
+#include "renderer.h"
+#include "simulation.h"
+#include "consts.h"
+#include "level.h"
+
+Renderer::Renderer()
+{
+  win_ = window_ptr(
+    SDL_CreateWindow(
+      "dispatcher",
+      100,
+      100,
+      WINDOW_SIZE.w(),
+      WINDOW_SIZE.h(),
+      SDL_WINDOW_SHOWN));
+
+  if (!win_)
+  {
+    throw sdl_error();
+  }
+
+  ren_ = renderer_ptr(
+    SDL_CreateRenderer(
+      win_.get(),
+      -1,
+      SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC));
+
+  if (!ren_)
+  {
+    throw sdl_error();
+  }
+
+  SDL_SetRenderDrawBlendMode(ren_.get(), SDL_BLENDMODE_MOD);
+  SDL_SetRenderDrawColor(ren_.get(), 255, 150, 255, 255);
+  SDL_RenderFillRect(ren_.get(), nullptr);
+}
+
+void Renderer::render(const Simulation& sim)
+{
+  texture_ptr canvas(
+    SDL_CreateTexture(
+      ren_.get(),
+      SDL_PIXELFORMAT_RGBA8888,
+      SDL_TEXTUREACCESS_TARGET,
+      WINDOW_SIZE.w(),
+      WINDOW_SIZE.h()));
+
+  if (!canvas)
+  {
+    throw sdl_error();
+  }
+
+  SDL_SetRenderTarget(ren_.get(), nullptr);
+  SDL_SetRenderDrawBlendMode(ren_.get(), SDL_BLENDMODE_NONE);
+  SDL_SetRenderDrawColor(ren_.get(), 255, 150, rand() % 255, 255);
+  SDL_RenderClear(ren_.get());
+
+  const Level& level = sim.getLevel();
+
+  for (size_t y = 0; y < level.getSize().h(); y++)
+  {
+    for (size_t x = 0; x < level.getSize().w(); x++)
+    {
+      int val = level.at(x, y) * 10;
+
+      SDL_SetRenderDrawColor(ren_.get(), val, val, 0, 255);
+
+      SDL_Rect rect {
+        static_cast<int>(x * TILE_SIZE.w()),
+        static_cast<int>(y * TILE_SIZE.h()),
+        TILE_SIZE.w(),
+        TILE_SIZE.h()
+      };
+
+      SDL_RenderFillRect(ren_.get(), &rect);
+    }
+  }
+
+  for (Simulation::id_type id : sim.getActive())
+  {
+    const Entity& entity = sim.getEntity(id);
+
+    SDL_SetRenderDrawColor(ren_.get(), 100, 100, 100, 255);
+
+    SDL_Rect rect {
+      static_cast<int>(entity.pos.x()),
+      static_cast<int>(entity.pos.y()),
+      static_cast<int>(entity.size.w()),
+      static_cast<int>(entity.size.h())
+    };
+
+    SDL_RenderFillRect(ren_.get(), &rect);
+  }
+
+  //SDL_RenderCopy(ren_.get(), canvas.get(), nullptr, nullptr);
+  SDL_RenderPresent(ren_.get());
+}
@@ -0,0 +1,126 @@
+#ifndef RENDERER_H_6A58EC30
+#define RENDERER_H_6A58EC30
+
+#include <SDL.h>
+#include <SDL_image.h>
+#include <stdexcept>
+#include <memory>
+
+class Simulation;
+
+class sdl_error : public std::logic_error {
+public:
+
+  sdl_error() : std::logic_error(SDL_GetError())
+  {
+  }
+};
+
+class img_error : public std::logic_error {
+public:
+
+  img_error() : std::logic_error(IMG_GetError())
+  {
+  }
+};
+
+class sdl_wrapper {
+public:
+
+  sdl_wrapper()
+  {
+    if (SDL_Init(SDL_INIT_VIDEO) != 0)
+    {
+      sdl_error ex;
+      SDL_Quit();
+
+        throw ex;
+    }
+  }
+
+  ~sdl_wrapper()
+  {
+    SDL_Quit();
+  }
+};
+
+class img_wrapper {
+public:
+
+  img_wrapper()
+  {
+    if (IMG_Init(IMG_INIT_PNG) != IMG_INIT_PNG)
+    {
+      img_error ex;
+      IMG_Quit();
+
+      throw ex;
+    }
+  }
+
+  ~img_wrapper()
+  {
+    IMG_Quit();
+  }
+};
+
+class window_deleter {
+public:
+
+  void operator()(SDL_Window* ptr)
+  {
+    SDL_DestroyWindow(ptr);
+  }
+};
+
+using window_ptr = std::unique_ptr<SDL_Window, window_deleter>;
+
+class renderer_deleter {
+public:
+
+  void operator()(SDL_Renderer* ptr)
+  {
+    SDL_DestroyRenderer(ptr);
+  }
+};
+
+using renderer_ptr = std::unique_ptr<SDL_Renderer, renderer_deleter>;
+
+class surface_deleter {
+public:
+
+  void operator()(SDL_Surface* ptr)
+  {
+    SDL_FreeSurface(ptr);
+  }
+};
+
+using surface_ptr = std::unique_ptr<SDL_Surface, surface_deleter>;
+
+class texture_deleter {
+public:
+
+  void operator()(SDL_Texture* ptr)
+  {
+    SDL_DestroyTexture(ptr);
+  }
+};
+
+using texture_ptr = std::unique_ptr<SDL_Texture, texture_deleter>;
+
+class Renderer {
+public:
+
+  Renderer();
+
+  void render(const Simulation& game);
+
+private:
+
+  sdl_wrapper sdl_;
+  img_wrapper img_;
+  window_ptr win_;
+  renderer_ptr ren_;
+};
+
+#endif /* end of include guard: RENDERER_H_6A58EC30 */
@@ -0,0 +1,115 @@
+#include "simulation.h"
+
+#include "consts.h"
+#include "level.h"
+
+void Simulation::tick(
+  double dt,
+  const Uint8* keystate)
+{
+  for (id_type id : active_)
+  {
+    Entity& entity = entities_.at(id);
+
+    // Control
+    if (entity.player &&
+        !entity.moving)
+    {
+      if (keystate[SDL_SCANCODE_LEFT] &&
+          entity.gridPos.x() > 0 &&
+          level_.getTileset().canPlayerMoveTo(
+            level_.at(entity.gridPos - vec2s { 1, 0 })))
+      {
+        entity.moving = true;
+        entity.destPos = entity.gridPos - vec2s { 1, 0 };
+      }
+      else if (keystate[SDL_SCANCODE_UP] &&
+          entity.gridPos.y() > 0 &&
+          level_.getTileset().canPlayerMoveTo(
+            level_.at(entity.gridPos - vec2s { 0, 1 })))
+      {
+        entity.moving = true;
+        entity.destPos = entity.gridPos - vec2s { 0, 1 };
+      } else if (keystate[SDL_SCANCODE_RIGHT] &&
+          entity.gridPos.x() < (level_.getSize().w() - 1) &&
+          level_.getTileset().canPlayerMoveTo(
+            level_.at(entity.gridPos + vec2s { 1, 0 })))
+      {
+        entity.moving = true;
+        entity.destPos = entity.gridPos + vec2s { 1, 0 };
+      }
+      else if (keystate[SDL_SCANCODE_DOWN] &&
+          entity.gridPos.y() < (level_.getSize().h() - 1) &&
+          level_.getTileset().canPlayerMoveTo(
+            level_.at(entity.gridPos + vec2s { 0, 1 })))
+      {
+        entity.moving = true;
+        entity.destPos = entity.gridPos + vec2s { 0, 1 };
+      }
+
+      if (entity.moving)
+      {
+        entity.movementTween = 0.0;
+      }
+    }
+
+
+
+
+    // Collision
+
+
+
+
+    // Movement
+    if (entity.moving)
+    {
+      entity.movementTween += entity.speed * dt;
+
+      if (entity.movementTween >= 1.0)
+      {
+        entity.moving = false;
+        entity.gridPos = entity.destPos;
+      }
+    }
+
+    if (entity.moving)
+    {
+      entity.pos.x() =
+        TILE_SIZE.x() * entity.destPos.x() * entity.movementTween +
+        TILE_SIZE.x() * entity.gridPos.x() * (1.0 - entity.movementTween);
+
+      entity.pos.y() =
+        TILE_SIZE.y() * entity.destPos.y() * entity.movementTween +
+        TILE_SIZE.y() * entity.gridPos.y() * (1.0 - entity.movementTween);
+    } else {
+      entity.pos = TILE_SIZE * entity.gridPos;
+    }
+  }
+}
+
+Simulation::id_type Simulation::emplaceEntity()
+{
+  id_type nextId;
+
+  if (!available_.empty())
+  {
+    nextId = available_.front();
+    available_.pop_front();
+
+    entities_.at(nextId) = Entity();
+  } else {
+    nextId = entities_.size();
+    entities_.emplace_back();
+  }
+
+  active_.insert(nextId);
+
+  return nextId;
+}
+
+void Simulation::deleteEntity(id_type id)
+{
+  available_.push_back(id);
+  active_.erase(id);
+}
@@ -0,0 +1,57 @@
+#ifndef SIMULATION_H_7BF6EEA4
+#define SIMULATION_H_7BF6EEA4
+
+#include "entity.h"
+#include "renderer.h"
+#include <vector>
+#include <deque>
+#include <set>
+
+class Level;
+
+class Simulation {
+public:
+
+  using id_type = std::vector<Entity>::size_type;
+
+  // Constructor
+  explicit Simulation(const Level& level) : level_(level) {}
+
+  void tick(
+    double dt,
+    const Uint8* keystate);
+
+  id_type emplaceEntity();
+
+  void deleteEntity(id_type id);
+
+  Entity& getEntity(id_type id)
+  {
+    return entities_.at(id);
+  }
+
+  const Entity& getEntity(id_type id) const
+  {
+    return entities_.at(id);
+  }
+
+  const std::set<id_type>& getActive() const
+  {
+    return active_;
+  }
+
+  const Level& getLevel() const
+  {
+    return level_;
+  }
+
+private:
+
+  const Level& level_;
+
+  std::vector<Entity> entities_;
+  std::deque<id_type> available_;
+  std::set<id_type> active_;
+};
+
+#endif /* end of include guard: SIMULATION_H_7BF6EEA4 */
@@ -0,0 +1,13 @@
+#ifndef TILESET_H_B89AE7A1
+#define TILESET_H_B89AE7A1
+
+class Tileset {
+public:
+
+  bool canPlayerMoveTo(size_t tile) const
+  {
+    return (tile % 2 == 1);
+  }
+};
+
+#endif /* end of include guard: TILESET_H_B89AE7A1 */
@@ -0,0 +1,119 @@
+#ifndef COORDINATES_H_A45D34FB
+#define COORDINATES_H_A45D34FB
+
+#include <cstddef>
+
+template <typename T>
+class vec2 {
+public:
+
+  T coords[2];
+
+  constexpr vec2() : coords{0, 0}
+  {
+  }
+
+  constexpr vec2(T x, T y) : coords{x, y}
+  {
+  }
+
+  inline T& x()
+  {
+    return coords[0];
+  }
+
+  constexpr inline const T& x() const
+  {
+    return coords[0];
+  }
+
+  inline T& w()
+  {
+    return coords[0];
+  }
+
+  constexpr inline const T& w() const
+  {
+    return coords[0];
+  }
+
+  inline T& y()
+  {
+    return coords[1];
+  }
+
+  constexpr inline const T& y() const
+  {
+    return coords[1];
+  }
+
+  inline T& h()
+  {
+    return coords[1];
+  }
+
+  constexpr inline const T& h() const
+  {
+    return coords[1];
+  }
+
+  template <typename R>
+  constexpr operator vec2<R>() const
+  {
+    return vec2<R>(x(), y());
+  }
+
+  constexpr vec2 operator+(const vec2& other) const
+  {
+    return vec2(x() + other.x(), y() + other.y());
+  }
+
+  vec2& operator+=(const vec2& other)
+  {
+    x() += other.x();
+    y() += other.y();
+
+    return *this;
+  }
+
+  constexpr vec2 operator-(const vec2& other) const
+  {
+    return vec2(x() - other.x(), y() - other.y());
+  }
+
+  vec2 operator-=(const vec2& other)
+  {
+    x() -= other.x();
+    y() -= other.y();
+
+    return *this;
+  }
+
+  constexpr vec2 operator-() const
+  {
+    return vec2(-x(), -y());
+  }
+
+  constexpr vec2 operator*(T s) const
+  {
+    return vec2(x() * s, y() * s);
+  }
+
+  vec2& operator*=(T s)
+  {
+    x() *= s;
+    y() *= s;
+
+    return *this;
+  }
+
+  constexpr vec2 operator*(const vec2& other) const
+  {
+    return vec2(x() * other.x(), y() * other.y());
+  }
+
+};
+
+using vec2s = vec2<size_t>;
+
+#endif /* end of include guard: COORDINATES_H_A45D34FB */