From 73d1206edbb3ec8d78df60cfd24b49196acb223b Mon Sep 17 00:00:00 2001
From: Luka Vandervelden <lukc@upyum.com>
Date: Thu, 1 Nov 2018 21:29:41 +0900
Subject: [PATCH] Initial commit.

---
 shard.yml   |  22 ++++++++
 src/main.cr | 153 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 175 insertions(+)
 create mode 100644 shard.yml
 create mode 100644 src/main.cr

diff --git a/shard.yml b/shard.yml
new file mode 100644
index 0000000..151c43f
--- /dev/null
+++ b/shard.yml
@@ -0,0 +1,22 @@
+name: naka
+version: 0.0.1
+
+authors:
+  - Lukc <lukc@upyum.com>
+
+description: |
+  Experimental Löve-like APIs for game programming.
+# Future description’s gonna be like “Game Programming no Aidoru!”.
+
+# Currently, game and libraries are merged, because everything’s still a WIP.
+# It’ll change, though. Soon. Probably.
+targets:
+  main:
+    main: src/main.cr
+
+dependencies:
+  sdl:
+    github: ysbaddaden/sdl.cr
+    branch: master # No upstream tag or branches provided. :(
+
+license: EUPLv1.2
diff --git a/src/main.cr b/src/main.cr
new file mode 100644
index 0000000..119a5b3
--- /dev/null
+++ b/src/main.cr
@@ -0,0 +1,153 @@
+
+require "sdl"
+require "sdl/image"
+
+## Helper code comes here
+
+class Naka
+	def self.init
+		SDL.init SDL::Init::VIDEO
+		SDL::IMG.init SDL::IMG::Init::PNG
+
+		at_exit { SDL.quit }
+	end
+end
+
+class Naka::Renderer < SDL::Renderer
+end
+
+class Naka::Window
+	alias Flags = LibSDL::WindowFlags
+	alias Position = LibSDL::WindowPosition
+
+	getter renderer
+
+	def initialize(title, width, height,
+				   x : Position = Position::UNDEFINED,
+				   y : Position = Position::UNDEFINED,
+				   flags : Flags = Flags::SHOWN)
+
+		@window = SDL::Window.new(title, width, height, x, y, flags)
+		@renderer = Naka::Renderer.new @window
+	end
+
+	def newImage(file_path) : SDL::Texture
+		SDL::IMG.load file_path, @renderer
+	end
+
+	# FIXME: We’ll probably want options for scaling, rotations, and so on.
+	def draw(texture : SDL::Texture, x : Int32, y : Int32)
+		@renderer.copy texture,
+			dstrect: SDL::Rect[x, y, texture.width, texture.height]
+	end
+end
+
+class Naka::Timer
+	getter start
+	getter last_update
+
+	def initialize
+		@start = Time.now
+		@last_update = @start
+	end
+
+	def step
+		now = Time.now
+
+		dt = now.epoch_ms - @last_update.epoch_ms
+
+		@last_update = now
+
+		dt
+	end
+end
+
+class Naka::Event
+	class Quit
+	end
+
+	class Draw
+		getter window : Naka::Window
+
+		def initialize(@window)
+		end
+	end
+
+	class Update
+		getter dt : Int64
+
+		def initialize(@dt)
+		end
+	end
+
+	# FIXME: THIS MAIN LOOP IS **NOT** READY FOR PRODUCTION
+	#        Update events are still missing, and both Draw and Update should
+	#        be time-based.
+	# Why having a `window` parameter instead of making a Window#loop method?
+	# Because we may want to have a `windows` parameter in the future, although
+	# unlikely. But still possible.
+	def self.loop(window, &block)
+		max_fps = 60
+		max_dt = 1000. / 60
+
+		timer = Naka::Timer.new
+
+		renderer = window.renderer
+
+		::loop do
+			exit_requested = false
+
+			while event = SDL::Event.poll
+				r_value = yield case event
+				when SDL::Event::Quit
+					Naka::Event::Quit.new
+				else # FIXME: Most event types may need proper Naka:: classes.
+					event
+				end
+
+				if r_value == Naka::Event::Quit
+					exit_requested = true
+					break
+				end
+			end
+
+			break if exit_requested
+
+			dt = timer.step
+
+			r_value = yield Naka::Event::Update.new dt
+
+			break if r_value == Naka::Event::Quit
+
+			renderer.draw_color = SDL::Color[255, 255, 255, 255]
+			renderer.clear
+
+			yield Naka::Event::Draw.new window
+
+			renderer.present
+
+			sleep 0.001
+		end
+	end
+end
+
+## Actual application code comes here
+
+Naka.init
+
+window = Naka::Window.new "Test", 640, 480 
+
+naka = window.newImage "naka.png"
+
+Naka::Event.loop window do |event|
+	case event
+	when Naka::Event::Quit
+		next Naka::Event::Quit
+	when Naka::Event::Update
+		p "Update(#{event.dt})"
+	when Naka::Event::Draw
+		p "Draw"
+		event.window.draw naka, 20, 20
+	end
+end
+