From 5d8712946d7a7a43f5670d5b6ef08951d3d07e4b Mon Sep 17 00:00:00 2001
From: Cyberarm <matthewlikesrobots@gmail.com>
Date: Mon, 7 Oct 2019 12:30:17 -0500
Subject: [PATCH] Camera#pick almost works, fixed Map tile exclusion

---
 lib/camera.rb      | 15 ++++++++++-----
 lib/map.rb         | 19 ++++++++++++-------
 lib/states/game.rb |  6 +++++-
 3 files changed, 27 insertions(+), 13 deletions(-)

diff --git a/lib/camera.rb b/lib/camera.rb
index fd20e85..f286557 100644
--- a/lib/camera.rb
+++ b/lib/camera.rb
@@ -20,7 +20,6 @@ class IMICRTS
     def draw(&block)
       if block
         Gosu.clip_to(@viewport.min.x, @viewport.min.y, @viewport.max.x, @viewport.max.y) do
-          center_point = center
           Gosu.transform(*worldspace.elements) do
             block.call
           end
@@ -39,7 +38,13 @@ class IMICRTS
     end
 
     def pick(vector)
-      inverse = (vector - @position) / @zoom
+      neg_center = CyberarmEngine::Vector.new(-center.x, -center.y)
+
+      scaled_position = ((vector - (@position)) / @zoom)
+      scaled_translation = (neg_center / @zoom + center)
+      # TODO: Fix error caused when @position != 0
+
+      inverse = (scaled_position + scaled_translation)
       inverse.x = inverse.x.floor
       inverse.y = inverse.y.floor
 
@@ -47,7 +52,7 @@ class IMICRTS
     end
 
     def center
-      (CyberarmEngine::Vector.new(window.width / 2, window.height / 2) - @position)
+      CyberarmEngine::Vector.new(window.width / 2, window.height / 2)
     end
 
     def center_around(vector, factor)
@@ -57,9 +62,9 @@ class IMICRTS
 
     def worldspace
       zoom_vector = CyberarmEngine::Vector.new(@zoom, @zoom)
-      position_matrix = CyberarmEngine::Matrix.translate(@position)
+      position_matrix = CyberarmEngine::Transform.translate(@position)
 
-      CyberarmEngine::Matrix.concat(CyberarmEngine::Matrix.scale(zoom_vector, center), position_matrix)
+      CyberarmEngine::Transform.concat(CyberarmEngine::Transform.scale(zoom_vector, center - @position), position_matrix)
     end
 
     def visible?(object)
diff --git a/lib/map.rb b/lib/map.rb
index 81e20d1..8a98366 100644
--- a/lib/map.rb
+++ b/lib/map.rb
@@ -32,19 +32,24 @@ class IMICRTS
     def visible_tiles(camera)
       _tiles = []
 
-      top_left = camera.center - CyberarmEngine::Vector.new($window.width / 2, $window.height / 2) / camera.zoom
-      top_left.x = top_left.x.ceil
-      top_left.y = top_left.y.ceil
-
+      top_left = (camera.center - camera.position) - CyberarmEngine::Vector.new($window.width / 2, $window.height / 2) / camera.zoom
       top_left /= @tile_size
 
+      top_left.x = top_left.x.floor
+      top_left.y = top_left.y.floor
+
+
       # +1 to overdraw a bit to hide pop-in
-      _width  = ($window.width / @tile_size)  + 1
-      _height = ($window.height / @tile_size) + 1
+      _width  = ((($window.width / @tile_size)  + 2) / camera.zoom).ceil
+      _height = ((($window.height / @tile_size) + 2) / camera.zoom).ceil
 
       _height.times do |y|
         _width.times do |x|
-          if tile = tile_at(x + top_left.x, y + top_left.y)
+          _x, _y = x + top_left.x, y + top_left.y
+          next if _x < 0 || _x > @width
+          next if _y < 0 || _y > @height
+
+          if tile = tile_at(_x, _y)
             _tiles.push(tile)
           end
         end
diff --git a/lib/states/game.rb b/lib/states/game.rb
index ac78f34..f653f63 100644
--- a/lib/states/game.rb
+++ b/lib/states/game.rb
@@ -60,7 +60,8 @@ class IMICRTS
         @director.entities.each(&:draw)
         @selected_entities.each(&:selected_draw)
 
-        draw_rect(@player.camera.center.x - 10, @player.camera.center.y - 10, 20, 20, Gosu::Color::RED, Float::INFINITY)
+        center = @player.camera.center - @player.camera.position
+        draw_rect(center.x - 10, center.y - 10, 20, 20, Gosu::Color::RED, Float::INFINITY)
 
         mouse = @player.camera.pick(window.mouse)
         draw_rect(mouse.x - 10, mouse.y - 10, 20, 20, Gosu::Color::YELLOW, Float::INFINITY)
@@ -95,6 +96,9 @@ class IMICRTS
         Window Mouse X: #{window.mouse.x}
         Window Mouse Y: #{window.mouse.y}
 
+        Camera Position X: #{@player.camera.position.x}
+        Camera Position Y: #{@player.camera.position.y}
+
         World Mouse X: #{mouse.x}
         World Mouse Y: #{mouse.y}