From ebb9245ccef8a6b9c908f82ecea6bea26dde14b5 Mon Sep 17 00:00:00 2001
From: tradam <git.tradam.fyi>
Date: Mon, 16 Aug 2021 14:09:49 -0400
Subject: it works

---
 README.mdown |  4 +---
 run.rb       | 39 +++++++++++++++++++++++++--------------
 2 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/README.mdown b/README.mdown
index 26024b5..bc923e1 100644
--- a/README.mdown
+++ b/README.mdown
@@ -1,7 +1,5 @@
 # hints and notes for Debugging
-- Shape A for some reason is not understood by the hitbox detection correctly  
-As can be seen with the debug lines, one of the lines is drawn diagnal when it instead should of been drawn online one of the edges. The other line has been determined to be of length 0 so it is as if the points are swapped. Despite both shapes using what appear to be essentially the same code only one of the two shapes are in error. If the a and b shapes are swapped then the issue switches shapes(from a to b) so the issue doesnt appear to be with declaring the shapes but rather something in the hitbox logic.
-- (Maybe??) because of this strange diagnal, it seems that the shapes collision is not correctly determined(try moving the shape just outside the lower left corner of the square and you can see it detects a collision where there is none)
+If the shape is brought to the bottom left corner then the hitbox collision fails
 
 # Links for the math
 see the comments at the top of `run.rb` for links that explain the math
diff --git a/run.rb b/run.rb
index 7e28c7b..eea11f1 100644
--- a/run.rb
+++ b/run.rb
@@ -18,6 +18,9 @@ require 'ruby2d/camera'
 $colors = %w[blue teal green lime
              yellow orange red fuchsia]
 
+set width: 800
+set height: 800
+
 #DEBUG: used to draw, store and update debug lines
 class DebugLines
   class << self
@@ -32,9 +35,9 @@ class DebugLines
 end
 
 # The coordinates of the 2 shapes being tested for collision
-svA = { x1: 200.0, y1: 100.0,
-        x2: 200.0, y2: 200.0,
-        x3: 100.0, y3: 200.0,
+svA = { x1: 230.0, y1: 100.0,
+        x2: 200.0, y2: 250.0,
+        x3: 50.0, y3: 200.0,
         x4: 100.0, y4: 100.0 }
 
 svB = { x1: 275.0 - 275.0, y1: 175.0 - 175.0,
@@ -43,11 +46,13 @@ svB = { x1: 275.0 - 275.0, y1: 175.0 - 175.0,
         x4: 250.0 - 275.0, y4: 250.0 - 175.0 }
 
 # The 2 shapes being tested for collision
+
 sA = Camera::Quad.new(
   **svA,
   color: 'olive',
   z: 10
 )
+
 sB = Camera::Quad.new(
   **svB,
   color: 'aqua',
@@ -57,11 +62,11 @@ sB = Camera::Quad.new(
 # The hitbox logic
 def hitbox_check(shape_a, shape_b)
   # Get normals of both shapes
-  inverted = build_inverted_edges(shape_b)
-  inverted.concat(build_inverted_edges(shape_a))
+  inverted = build_inverted_edges(shape_a)
+  inverted.concat(build_inverted_edges(shape_b))
 
   #DEBUG
-  debug_outer_loop(inverted)
+  #debug_outer_loop(inverted)
 
   inverted.each_with_index do |line, line_index|
     # Determine max and min of a and b shapes
@@ -69,14 +74,14 @@ def hitbox_check(shape_a, shape_b)
     bmax, bmin = calculate_minmax(shape_b, line)
 
     #DEBUG
-    debug_inner_loop(shape_a, shape_b, line_index, amax, amin, bmax, bmin)
+    #debug_inner_loop(shape_a, shape_b, line_index, amax, amin, bmax, bmin)
 
     if ((amin <= bmax) && (amin >= bmin)) || ((bmin <= amax) && (bmin >= amin))
       #next
     else
       # The logic should end the calculations early once it detects lack of collision
       # however for debug purposes this is disabled
-      #return false
+      return false
     end
   end
   true
@@ -125,12 +130,12 @@ def debug_inner_loop(shape_a, shape_b, line_index, amax, amin, bmax, bmin)
   if line_index < shape_a.length
     DebugLines[line_index].x1 = shape_a[line_index][0]
     DebugLines[line_index].y1 = shape_a[line_index][1]
-    if shape_a[line_index].nil?
-      DebugLines[line_index].x2 = shape_a[line_index + 1][0]
-      DebugLines[line_index].y2 = shape_a[line_index + 1][1]
-    else
+    if shape_a[line_index + 1].nil?
       DebugLines[line_index].x2 = shape_a[0][0]
       DebugLines[line_index].y2 = shape_a[0][1]
+    else
+      DebugLines[line_index].x2 = shape_a[line_index + 1][0]
+      DebugLines[line_index].y2 = shape_a[line_index + 1][1]
     end
   else
     DebugLines[line_index].x1 = shape_b[line_index - shape_a.length][0]
@@ -203,8 +208,8 @@ update do
   $i %= 5
 
   # Update shape 1 position to mouse
-  sB.x = Camera.coordinate_to_worldspace(get(:mouse_x), 0)[0]
-  sB.y = Camera.coordinate_to_worldspace(0, get(:mouse_y))[1]
+  sB.x = Camera.coordinate_to_worldspace(get(:mouse_x), 0)[0] - 25
+  sB.y = Camera.coordinate_to_worldspace(0, get(:mouse_y))[1] - 75
 
   # Check hitboxes
   a = hitbox_check(
@@ -218,6 +223,12 @@ update do
      [sB.x4 + sB.x, sB.y4 + sB.y]]
   )
 
+  if a
+    sB.color = 'red'
+  else
+    sB.color = 'aqua'
+  end
+
   #DEBUG
   if $i == 0
     pp [[sA.x1, sA.y1],
-- 
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