From 68b52b7edc4c562096d6ecf0242535a6d2bada3d Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Sun, 19 May 2019 15:38:19 -0400
Subject: [PATCH 01/15] Camera: Update frame_top/frame_bottom

---
 ppb/camera.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ppb/camera.py b/ppb/camera.py
index 6a9d58ee..9a88c6a8 100644
--- a/ppb/camera.py
+++ b/ppb/camera.py
@@ -35,11 +35,11 @@ def __init__(self, viewport: Sequence[int]=(0, 0, 800, 600),
 
     @property
     def frame_top(self) -> Number:
-        return self.position.y - self.half_height
+        return self.position.y + self.half_height
 
     @property
     def frame_bottom(self) -> Number:
-        return self.position.y + self.half_height
+        return self.position.y - self.half_height
 
     @property
     def frame_left(self) -> Number:

From 2de1d3ac92f517811e50fc96a7c6e4f6927da816 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Sun, 19 May 2019 15:57:22 -0400
Subject: [PATCH 02/15] Sprites: Update SIDES map

---
 ppb/sprites.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ppb/sprites.py b/ppb/sprites.py
index f9b0cf8e..9abdc37d 100644
--- a/ppb/sprites.py
+++ b/ppb/sprites.py
@@ -21,8 +21,8 @@ class Side:
     sides = {
         LEFT: ('x', -1),
         RIGHT: ('x', 1),
-        TOP: ('y', -1),
-        BOTTOM: ('y', 1)
+        TOP: ('y', 1),
+        BOTTOM: ('y', -1)
     }
 
     def __init__(self, parent: 'BaseSprite', side: str):

From 597abf9cb69d20668c54ff05eeb73eba0960908f Mon Sep 17 00:00:00 2001
From: Piper Thunstrom <pathunstrom@gmail.com>
Date: Sun, 19 May 2019 19:07:16 -0400
Subject: [PATCH 03/15] Adds more translate_to_viewport tests, fixes bad tests.

---
 tests/test_camera.py | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/tests/test_camera.py b/tests/test_camera.py
index b28bfec7..54275f04 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -42,8 +42,16 @@ def test_camera_translate_to_viewport():
     assert cam.translate_to_viewport(Vector(0, 0)) == Vector(400, 300)
     assert cam.translate_to_viewport(Vector(2, 1)) == Vector(560, 220)
     cam.position = Vector(5, 5)
-    assert cam.translate_to_viewport(Vector(5, -5)) == Vector(400, 300)
-    assert cam.translate_to_viewport(Vector(7, -4)) == Vector(560, 220)
+    assert cam.translate_to_viewport(Vector(5, 5)) == Vector(400, 300)
+    assert cam.translate_to_viewport(Vector(7, 4)) == Vector(560, 380)
+
+
+def test_camera_translate_to_viewport_2():
+    cam = Camera(viewport=(0, 0, 800, 600), pixel_ratio=1)
+    assert cam.position == Vector(0, 0)
+    assert cam.translate_to_viewport(Vector(0, 0)) == Vector(400, 300)
+    assert cam.translate_to_viewport(Vector(100, 100)) == Vector(500, 200)
+    assert cam.translate_to_viewport(Vector(-150, -500)) == Vector(250, 800)
 
 
 def test_sprite_in_viewport():

From 3123703dbc0118363d3ee4b761e6f1367e218570 Mon Sep 17 00:00:00 2001
From: Piper Thunstrom <pathunstrom@gmail.com>
Date: Sun, 19 May 2019 19:07:44 -0400
Subject: [PATCH 04/15] Fixes translate_to_viewport

---
 ppb/camera.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/ppb/camera.py b/ppb/camera.py
index 9a88c6a8..c1fac1b9 100644
--- a/ppb/camera.py
+++ b/ppb/camera.py
@@ -6,6 +6,7 @@
 from ppb.sprites import BaseSprite
 from ppb.flags import DoNotRender
 
+
 class Camera(BaseSprite):
 
     image = DoNotRender
@@ -108,6 +109,4 @@ def translate_to_viewport(self, point: Vector) -> Vector:
         """
         Converts a vector from in-game to pixel-based window coordinate space
         """
-        point = point.update(y=-point.y)
-        offset = (point - self.position) * self.pixel_ratio
-        return self.viewport_offset + offset
+        return Vector(point.x - self.frame_left, self.frame_top - point.y) * self.pixel_ratio
\ No newline at end of file

From 5de5a478f399336fb372696b14beb740a2535243 Mon Sep 17 00:00:00 2001
From: Piper Thunstrom <pathunstrom@gmail.com>
Date: Sun, 19 May 2019 19:10:08 -0400
Subject: [PATCH 05/15] Fixes Camera.in_frame

---
 ppb/camera.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ppb/camera.py b/ppb/camera.py
index c1fac1b9..accf276c 100644
--- a/ppb/camera.py
+++ b/ppb/camera.py
@@ -93,8 +93,8 @@ def point_in_viewport(self, point:Vector) -> bool:
     def in_frame(self, sprite: BaseSprite) -> bool:
         return (self.frame_left <= sprite.right and
                 self.frame_right >= sprite.left and
-                self.frame_top <= sprite.bottom and
-                self.frame_bottom >= sprite.top
+                self.frame_top >= sprite.bottom and
+                self.frame_bottom <= sprite.top
                 )
 
     def translate_to_frame(self, point: Vector) -> Vector:

From 2536dd7bea3f4968d29b1ce612d539ce7d689fb2 Mon Sep 17 00:00:00 2001
From: Piper Thunstrom <pathunstrom@gmail.com>
Date: Sun, 19 May 2019 19:27:58 -0400
Subject: [PATCH 06/15] Fixes sprite tests.

---
 ppb/camera.py         |  2 +-
 tests/test_sprites.py | 52 +++++++++++++++++++++----------------------
 2 files changed, 27 insertions(+), 27 deletions(-)

diff --git a/ppb/camera.py b/ppb/camera.py
index accf276c..010cc866 100644
--- a/ppb/camera.py
+++ b/ppb/camera.py
@@ -109,4 +109,4 @@ def translate_to_viewport(self, point: Vector) -> Vector:
         """
         Converts a vector from in-game to pixel-based window coordinate space
         """
-        return Vector(point.x - self.frame_left, self.frame_top - point.y) * self.pixel_ratio
\ No newline at end of file
+        return Vector(point.x - self.frame_left, self.frame_top - point.y) * self.pixel_ratio
diff --git a/tests/test_sprites.py b/tests/test_sprites.py
index da84761f..e1ced2c9 100644
--- a/tests/test_sprites.py
+++ b/tests/test_sprites.py
@@ -60,31 +60,31 @@ def test_right(self):
         self.assertEqual(self.sprite.position.y, 0)
 
     def test_top(self):
-        self.assertEqual(self.sprite.top, -0.5)
-        self.assertEqual(self.wide_sprite.top, 1)
+        self.assertEqual(self.sprite.top, 0.5)
+        self.assertEqual(self.wide_sprite.top, 3)
 
         self.sprite.top = 0
         self.assertEqual(self.sprite.position.x, 0)
-        self.assertEqual(self.sprite.position.y, 0.5)
+        self.assertEqual(self.sprite.position.y, -0.5)
 
         self.sprite.top += 2
         self.assertEqual(self.sprite.position.x, 0)
-        self.assertEqual(self.sprite.position.y, 2.5)
+        self.assertEqual(self.sprite.position.y, 1.5)
 
     def test_bottom(self):
-        self.assertEqual(self.sprite.bottom, 0.5)
-        self.assertEqual(self.wide_sprite.bottom, 3)
+        self.assertEqual(self.sprite.bottom, -0.5)
+        self.assertEqual(self.wide_sprite.bottom, 1)
 
         self.sprite.bottom = 0
         self.assertEqual(self.sprite.position.x, 0)
-        self.assertEqual(self.sprite.position.y, -0.5)
+        self.assertEqual(self.sprite.position.y, 0.5)
 
         self.sprite.bottom += 2
         self.assertEqual(self.sprite.position.x, 0)
-        self.assertEqual(self.sprite.position.y, 1.5)
+        self.assertEqual(self.sprite.position.y, 2.5)
 
     def test_left_top(self):
-        self.assertEqual(self.sprite.left.top, Vector(-0.5, -0.5))
+        self.assertEqual(self.sprite.left.top, Vector(-0.5, 0.5))
 
         self.sprite.left.top = (2, 2)
         self.assertEqual(self.sprite.left.top, Vector(2, 2))
@@ -95,10 +95,10 @@ def test_left_top(self):
         result = self.sprite.left.top + (3, 3)
         self.assertEqual(result, Vector(7, 7))
 
-        self.assertEqual(self.sprite.position, Vector(4.5, 4.5))
+        self.assertEqual(self.sprite.position, Vector(4.5, 3.5))
 
     def test_left_bottom(self):
-        self.assertEqual(self.sprite.left.bottom, Vector(-0.5, 0.5))
+        self.assertEqual(self.sprite.left.bottom, Vector(-0.5, -0.5))
 
         self.sprite.left.bottom = (1, 2)
         self.assertEqual(self.sprite.left.bottom, Vector(1, 2))
@@ -109,7 +109,7 @@ def test_left_bottom(self):
         result = self.sprite.left.bottom + (3, 2)
         self.assertEqual(result, Vector(6, 5))
 
-        self.assertEqual(self.sprite.position, Vector(3.5, 2.5))
+        self.assertEqual(self.sprite.position, Vector(3.5, 3.5))
 
     def test_left_center(self):
         self.assertEqual(self.sprite.left.center, Vector(-0.5, 0))
@@ -126,7 +126,7 @@ def test_left_center(self):
         self.assertEqual(self.sprite.position, Vector(3.5, 2))
 
     def test_right_bottom(self):
-        self.assertEqual(self.sprite.right.bottom, Vector(0.5, 0.5))
+        self.assertEqual(self.sprite.right.bottom, Vector(0.5, -0.5))
 
         self.sprite.right.bottom = (1, 1)
         self.assertEqual(self.sprite.right.bottom, Vector(1, 1))
@@ -137,10 +137,10 @@ def test_right_bottom(self):
         result = self.sprite.right.bottom + (2, 3)
         self.assertEqual(result, Vector(5, 5))
 
-        self.assertEqual(self.sprite.position, Vector(2.5, 1.5))
+        self.assertEqual(self.sprite.position, Vector(2.5, 2.5))
 
     def test_right_top(self):
-        self.assertEqual(self.sprite.right.top, Vector(0.5, -0.5))
+        self.assertEqual(self.sprite.right.top, Vector(0.5, 0.5))
 
         self.sprite.right.top = (1, 1)
         self.assertEqual(self.sprite.right.top, Vector(1, 1))
@@ -151,7 +151,7 @@ def test_right_top(self):
         result = self.sprite.right.top + (2, 3)
         self.assertEqual(result, Vector(5, 5))
 
-        self.assertEqual(self.sprite.position, Vector(2.5, 2.5))
+        self.assertEqual(self.sprite.position, Vector(2.5, 1.5))
 
     def test_right_center(self):
         self.assertEqual(self.sprite.right.center, Vector(0.5, 0))
@@ -184,7 +184,7 @@ def test_right_left(self):
         self.assertRaises(AttributeError, setattr, self.sprite.right, "left", Vector(1, 1))
 
     def test_top_left(self):
-        self.assertEqual(self.sprite.top.left, Vector(-0.5, -0.5))
+        self.assertEqual(self.sprite.top.left, Vector(-0.5, 0.5))
 
         self.sprite.top.left = (2, 2)
         self.assertEqual(self.sprite.top.left, Vector(2, 2))
@@ -195,10 +195,10 @@ def test_top_left(self):
         result = self.sprite.top.left + (3, 3)
         self.assertEqual(result, Vector(7, 7))
 
-        self.assertEqual(self.sprite.position, Vector(4.5, 4.5))
+        self.assertEqual(self.sprite.position, Vector(4.5, 3.5))
 
     def test_top_right(self):
-        self.assertEqual(self.sprite.top.right, Vector(0.5, -0.5))
+        self.assertEqual(self.sprite.top.right, Vector(0.5, 0.5))
 
         self.sprite.top.right = (1, 1)
         self.assertEqual(self.sprite.top.right, Vector(1, 1))
@@ -209,10 +209,10 @@ def test_top_right(self):
         result = self.sprite.top.right + (2, 3)
         self.assertEqual(result, Vector(5, 5))
 
-        self.assertEqual(self.sprite.position, Vector(2.5, 2.5))
+        self.assertEqual(self.sprite.position, Vector(2.5, 1.5))
 
     def test_top_center(self):
-        self.assertEqual(self.sprite.top.center, Vector(0, -0.5))
+        self.assertEqual(self.sprite.top.center, Vector(0, 0.5))
 
         self.sprite.top.center = (1, 1)
         self.assertEqual(self.sprite.top.center, Vector(1, 1))
@@ -226,7 +226,7 @@ def test_top_bottom(self):
         self.assertRaises(AttributeError, setattr, self.sprite.top, "bottom", Vector(1, 1))
 
     def test_bottom_left(self):
-        self.assertEqual(self.sprite.bottom.left, Vector(-0.5, 0.5))
+        self.assertEqual(self.sprite.bottom.left, Vector(-0.5, -0.5))
 
         self.sprite.bottom.left = (2, 2)
         self.assertEqual(self.sprite.bottom.left, Vector(2, 2))
@@ -237,10 +237,10 @@ def test_bottom_left(self):
         result = self.sprite.bottom.left + (3, 3)
         self.assertEqual(result, Vector(7, 7))
 
-        self.assertEqual(self.sprite.position, Vector(4.5, 3.5))
+        self.assertEqual(self.sprite.position, Vector(4.5, 4.5))
 
     def test_bottom_right(self):
-        self.assertEqual(self.sprite.bottom.right, Vector(0.5, 0.5))
+        self.assertEqual(self.sprite.bottom.right, Vector(0.5, -0.5))
 
         self.sprite.bottom.right = (1, 1)
         self.assertEqual(self.sprite.bottom.right, Vector(1, 1))
@@ -251,10 +251,10 @@ def test_bottom_right(self):
         result = self.sprite.bottom.right + (2, 3)
         self.assertEqual(result, Vector(5, 5))
 
-        self.assertEqual(self.sprite.position, Vector(2.5, 1.5))
+        self.assertEqual(self.sprite.position, Vector(2.5, 2.5))
 
     def test_bottom_center(self):
-        self.assertEqual(self.sprite.bottom.center, Vector(0, 0.5))
+        self.assertEqual(self.sprite.bottom.center, Vector(0, -0.5))
 
         self.sprite.bottom.center = (1, 1)
         self.assertEqual(self.sprite.bottom.center, Vector(1, 1))

From 1691e5be7f863ce31c82ddbd53d5927a5c4d862b Mon Sep 17 00:00:00 2001
From: Piper Thunstrom <pathunstrom@gmail.com>
Date: Sun, 19 May 2019 19:28:22 -0400
Subject: [PATCH 07/15] Fixes top and bottom setters on Sprite.

---
 ppb/sprites.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ppb/sprites.py b/ppb/sprites.py
index 9abdc37d..61c02198 100644
--- a/ppb/sprites.py
+++ b/ppb/sprites.py
@@ -272,7 +272,7 @@ def top(self):
 
     @top.setter
     def top(self, value):
-        self.position = Vector(self.position.x, value + self._offset_value)
+        self.position = Vector(self.position.x, value - self._offset_value)
 
     @property
     def bottom(self):
@@ -280,7 +280,7 @@ def bottom(self):
 
     @bottom.setter
     def bottom(self, value):
-        self.position = Vector(self.position.x, value - self._offset_value)
+        self.position = Vector(self.position.x, value + self._offset_value)
 
     @property
     def _offset_value(self):

From e37db7e170baddc97b976be96d71626972f29509 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Tue, 21 May 2019 15:25:54 -0400
Subject: [PATCH 08/15] Add a hypothesis test

---
 tests/test_camera.py | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/tests/test_camera.py b/tests/test_camera.py
index 54275f04..9e654394 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -2,6 +2,9 @@
 from ppb import Vector
 from ppb.camera import Camera
 
+from hypothesis import given
+import hypothesis.strategies as st
+
 
 def test_camera_move():
     cam = Camera()
@@ -79,3 +82,24 @@ def test_viewport_change_affects_frame_height():
     assert cam.frame_left == -5
     cam.viewport_width = 400
     assert cam.frame_left == -2.5
+
+
+@given(
+    vp_width=st.integers(min_value=1),
+    vp_height=st.integers(min_value=1),
+    pixel_ratio=st.floats(min_value=1, allow_nan=False, allow_infinity=False),
+    cam_x=st.floats(allow_nan=False, allow_infinity=False),
+    cam_y=st.floats(allow_nan=False, allow_infinity=False),
+    point_x=st.floats(allow_nan=False, allow_infinity=False),
+    point_y=st.floats(allow_nan=False, allow_infinity=False),
+)
+def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y, point_x, point_y):
+    cam = Camera(
+        viewport=(0, 0, vp_width, vp_height),
+        pixel_ratio=pixel_ratio,
+    )
+    cam.position = Vector(cam_x, cam_y)
+    point = Vector(point_x, point_y)
+
+    assert cam.translate_to_viewport(cam.translate_to_frame(point)) == point
+    assert cam.translate_to_frame(cam.translate_to_viewport(point)) == point

From 3e7f09f7b997a4ac5c02c0b47a736730548b5082 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Tue, 21 May 2019 17:09:54 -0400
Subject: [PATCH 09/15] Camera: Add a metamorphic test

---
 tests/test_camera.py | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/tests/test_camera.py b/tests/test_camera.py
index 9e654394..514f353b 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -2,7 +2,7 @@
 from ppb import Vector
 from ppb.camera import Camera
 
-from hypothesis import given
+from hypothesis import given, assume
 import hypothesis.strategies as st
 
 
@@ -103,3 +103,33 @@ def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y
 
     assert cam.translate_to_viewport(cam.translate_to_frame(point)) == point
     assert cam.translate_to_frame(cam.translate_to_viewport(point)) == point
+
+
+@given(
+    vp_width=st.integers(min_value=1),
+    vp_height=st.integers(min_value=1),
+    pixel_ratio=st.floats(min_value=1, allow_nan=False, allow_infinity=False),
+    cam_x=st.floats(allow_nan=False, allow_infinity=False),
+    cam_y=st.floats(allow_nan=False, allow_infinity=False),
+    point_x=st.floats(allow_nan=False, allow_infinity=False),
+    point_y=st.floats(allow_nan=False, allow_infinity=False),
+    delta_x=st.floats(allow_nan=False, allow_infinity=False),
+    delta_y=st.floats(allow_nan=False, allow_infinity=False),
+)
+def test_transfromation_movement(
+    vp_width, vp_height, pixel_ratio, cam_x, cam_y, point_x, point_y, delta_x, delta_y,
+):
+    cam = Camera(
+        viewport=(0, 0, vp_width, vp_height),
+        pixel_ratio=pixel_ratio,
+    )
+    cam.position = Vector(cam_x, cam_y)
+    point = Vector(point_x, point_y)
+    delta = Vector(delta_x, delta_y)
+
+    assume(delta.length != 0)
+
+    point_moved = point + delta
+
+    assert (cam.translate_to_frame(point_moved) - cam.translate_to_frame(point)).length / delta.length == pixel_ratio
+    assert delta.length / (cam.translate_to_viewport(point_moved) - cam.translate_to_viewport(point)).length == pixel_ratio

From a3f48e843719d03363b3e8331a71b5268086fc95 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Tue, 21 May 2019 17:28:06 -0400
Subject: [PATCH 10/15] Camera: Attempted to rewrite translate_to_frame(),
 failed

---
 ppb/camera.py        | 13 ++++++-------
 tests/test_camera.py |  4 ++++
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/ppb/camera.py b/ppb/camera.py
index 010cc866..9789fe1d 100644
--- a/ppb/camera.py
+++ b/ppb/camera.py
@@ -1,5 +1,4 @@
 from typing import Sequence
-from typing import Union
 from numbers import Number
 
 from ppb import Vector
@@ -11,8 +10,8 @@ class Camera(BaseSprite):
 
     image = DoNotRender
 
-    def __init__(self, viewport: Sequence[int]=(0, 0, 800, 600),
-                 pixel_ratio: float=64):
+    def __init__(self, viewport: Sequence[int] = (0, 0, 800, 600),
+                 pixel_ratio: float = 64):
         """
 
         viewport: A container of origin x, origin y, width, and
@@ -65,6 +64,7 @@ def half_height(self) -> float:
     @property
     def half_width(self) -> float:
         return self.frame_width / 2
+
     @property
     def viewport_width(self) -> int:
         return self._viewport_width
@@ -83,7 +83,7 @@ def viewport_height(self, value: int):
         self._viewport_height = value
         self.viewport_offset = Vector(self.viewport_width / 2, value / 2)
 
-    def point_in_viewport(self, point:Vector) -> bool:
+    def point_in_viewport(self, point: Vector) -> bool:
         px, py = point
         vpx, vpy = self.viewport_origin
         vpw = self.viewport_width
@@ -101,9 +101,8 @@ def translate_to_frame(self, point: Vector) -> Vector:
         """
         Converts a vector from pixel-based window to in-game coordinate space
         """
-        offset = (point - self.viewport_offset) * (1/self.pixel_ratio)
-        loc = self.position + offset
-        return loc.update(y=-loc.y)
+        scaled = point / self.pixel_ratio
+        return Vector(self.frame_left + scaled.x, self.frame_top - point.y)
 
     def translate_to_viewport(self, point: Vector) -> Vector:
         """
diff --git a/tests/test_camera.py b/tests/test_camera.py
index 514f353b..b3ad5f11 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -32,6 +32,10 @@ def test_camera_point_in_viewport_not_at_origin():
 def test_camera_translate_to_frame():
     cam = Camera(viewport=(0, 0, 800, 600), pixel_ratio=80)
     assert cam.position == Vector(0, 0)
+    assert cam.frame_top == 3.75
+    assert cam.frame_bottom == -3.75
+    assert cam.frame_left == -5
+    assert cam.frame_right == 5
     assert cam.translate_to_frame(Vector(400, 300)) == Vector(0, 0)
     assert cam.translate_to_frame(Vector(560, 220)) == Vector(2, 1)
     cam.position = Vector(5, 5)

From faf341fe3bde146e5c5aca835305b287a37ce948 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Thu, 23 May 2019 13:32:09 -0400
Subject: [PATCH 11/15] Camera: Fix up viewport->frame conversion

---
 ppb/camera.py        |  6 +++++-
 tests/test_camera.py | 16 ++++++++++------
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/ppb/camera.py b/ppb/camera.py
index 9789fe1d..6d407f1c 100644
--- a/ppb/camera.py
+++ b/ppb/camera.py
@@ -101,11 +101,15 @@ def translate_to_frame(self, point: Vector) -> Vector:
         """
         Converts a vector from pixel-based window to in-game coordinate space
         """
+        # 1. Scale from pixels to game unites
         scaled = point / self.pixel_ratio
-        return Vector(self.frame_left + scaled.x, self.frame_top - point.y)
+        # 2. Reposition relative to frame edges
+        return Vector(self.frame_left + scaled.x, self.frame_top - scaled.y)
 
     def translate_to_viewport(self, point: Vector) -> Vector:
         """
         Converts a vector from in-game to pixel-based window coordinate space
         """
+        # 1. Reposition based on frame edges
+        # 2. Scale from game units to pixels
         return Vector(point.x - self.frame_left, self.frame_top - point.y) * self.pixel_ratio
diff --git a/tests/test_camera.py b/tests/test_camera.py
index b3ad5f11..94968029 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -1,3 +1,5 @@
+from math import isclose
+
 from ppb import BaseSprite
 from ppb import Vector
 from ppb.camera import Camera
@@ -39,8 +41,8 @@ def test_camera_translate_to_frame():
     assert cam.translate_to_frame(Vector(400, 300)) == Vector(0, 0)
     assert cam.translate_to_frame(Vector(560, 220)) == Vector(2, 1)
     cam.position = Vector(5, 5)
-    assert cam.translate_to_frame(Vector(400, 300)) == Vector(5, -5)
-    assert cam.translate_to_frame(Vector(560, 220)) == Vector(7, -4)
+    assert cam.translate_to_frame(Vector(400, 300)) == Vector(5, 5)
+    assert cam.translate_to_frame(Vector(560, 220)) == Vector(7, 6)
 
 
 def test_camera_translate_to_viewport():
@@ -105,8 +107,8 @@ def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y
     cam.position = Vector(cam_x, cam_y)
     point = Vector(point_x, point_y)
 
-    assert cam.translate_to_viewport(cam.translate_to_frame(point)) == point
-    assert cam.translate_to_frame(cam.translate_to_viewport(point)) == point
+    assert cam.translate_to_viewport(cam.translate_to_frame(point)).isclose(point, abs_tol=1e-5)
+    assert cam.translate_to_frame(cam.translate_to_viewport(point)).isclose(point, abs_tol=1e-5)
 
 
 @given(
@@ -135,5 +137,7 @@ def test_transfromation_movement(
 
     point_moved = point + delta
 
-    assert (cam.translate_to_frame(point_moved) - cam.translate_to_frame(point)).length / delta.length == pixel_ratio
-    assert delta.length / (cam.translate_to_viewport(point_moved) - cam.translate_to_viewport(point)).length == pixel_ratio
+    diff = cam.translate_to_frame(point_moved) - cam.translate_to_frame(point)
+    assert isclose(diff.length / delta.length, pixel_ratio)
+    diff = cam.translate_to_viewport(point_moved) - cam.translate_to_viewport(point)
+    assert isclose(delta.length / diff.length, pixel_ratio)

From 006eb2511850588b62bec31aa950b810b1f653f8 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Fri, 24 May 2019 12:27:13 -0400
Subject: [PATCH 12/15] Camera: Work on transform tests more

---
 tests/test_camera.py | 40 +++++++++++++++++++++++++++++++++-------
 1 file changed, 33 insertions(+), 7 deletions(-)

diff --git a/tests/test_camera.py b/tests/test_camera.py
index 94968029..d035aa57 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -4,7 +4,7 @@
 from ppb import Vector
 from ppb.camera import Camera
 
-from hypothesis import given, assume
+from hypothesis import given, assume, note, example
 import hypothesis.strategies as st
 
 
@@ -93,12 +93,13 @@ def test_viewport_change_affects_frame_height():
 @given(
     vp_width=st.integers(min_value=1),
     vp_height=st.integers(min_value=1),
-    pixel_ratio=st.floats(min_value=1, allow_nan=False, allow_infinity=False),
+    pixel_ratio=st.floats(min_value=1, max_value=1e5, allow_nan=False, allow_infinity=False),
     cam_x=st.floats(allow_nan=False, allow_infinity=False),
     cam_y=st.floats(allow_nan=False, allow_infinity=False),
     point_x=st.floats(allow_nan=False, allow_infinity=False),
     point_y=st.floats(allow_nan=False, allow_infinity=False),
 )
+@example(vp_width=1, vp_height=1, pixel_ratio=1.0, cam_x=0.0, cam_y=0.0, point_x=0.0, point_y=0.0)
 def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y, point_x, point_y):
     cam = Camera(
         viewport=(0, 0, vp_width, vp_height),
@@ -107,14 +108,30 @@ def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y
     cam.position = Vector(cam_x, cam_y)
     point = Vector(point_x, point_y)
 
-    assert cam.translate_to_viewport(cam.translate_to_frame(point)).isclose(point, abs_tol=1e-5)
-    assert cam.translate_to_frame(cam.translate_to_viewport(point)).isclose(point, abs_tol=1e-5)
+    # Some underflow/loss of resolution problems
+    assume(cam.frame_left != cam.frame_right)
+    assume(cam.frame_top != cam.frame_bottom)
+
+    note(f"frame: ({cam.frame_left}, {cam.frame_bottom}) -> ({cam.frame_right}, {cam.frame_top})")
+    note(f"point: {point}")
+
+    point_frame = cam.translate_to_frame(point)
+    note(f"point->frame: {point_frame}")
+    point_viewport = cam.translate_to_viewport(point_frame)
+    note(f"point->frame->viewport: {point_viewport}")
+    assert point_viewport.isclose(point, rel_tol=1e-5)
+
+    point_viewport = cam.translate_to_viewport(point)
+    note(f"point->viewport: {point_viewport}")
+    point_frame = cam.translate_to_viewport(point_viewport)
+    note(f"point->viewport->frame: {point_frame}")
+    assert point_frame.isclose(point, rel_tol=1e-5)
 
 
 @given(
     vp_width=st.integers(min_value=1),
     vp_height=st.integers(min_value=1),
-    pixel_ratio=st.floats(min_value=1, allow_nan=False, allow_infinity=False),
+    pixel_ratio=st.floats(min_value=1, max_value=1e5, allow_nan=False, allow_infinity=False),
     cam_x=st.floats(allow_nan=False, allow_infinity=False),
     cam_y=st.floats(allow_nan=False, allow_infinity=False),
     point_x=st.floats(allow_nan=False, allow_infinity=False),
@@ -133,11 +150,20 @@ def test_transfromation_movement(
     point = Vector(point_x, point_y)
     delta = Vector(delta_x, delta_y)
 
+    note(f"point: {point}")
+    note(f"delta: {delta}")
+
     assume(delta.length != 0)
 
     point_moved = point + delta
 
+    assume(point_moved != point)  # This will happen when delta is too small to make an effect
+
+    note(f"point moved: {point_moved}")
+
     diff = cam.translate_to_frame(point_moved) - cam.translate_to_frame(point)
-    assert isclose(diff.length / delta.length, pixel_ratio)
+    note(f"frame diff: {diff}")
+    assert isclose(delta.length / diff.length, pixel_ratio, rel_tol=1e-5)
     diff = cam.translate_to_viewport(point_moved) - cam.translate_to_viewport(point)
-    assert isclose(delta.length / diff.length, pixel_ratio)
+    note(f"viewport diff: {diff}")
+    assert isclose(diff.length / delta.length, pixel_ratio, rel_tol=1e-5)

From b280bd6463ab9ee18e57d664f92b745ae624a2d3 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Fri, 24 May 2019 14:15:56 -0400
Subject: [PATCH 13/15] Camera: Fix test_transfromation_roundtrip

---
 tests/test_camera.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/test_camera.py b/tests/test_camera.py
index d035aa57..43cad3f6 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -99,7 +99,7 @@ def test_viewport_change_affects_frame_height():
     point_x=st.floats(allow_nan=False, allow_infinity=False),
     point_y=st.floats(allow_nan=False, allow_infinity=False),
 )
-@example(vp_width=1, vp_height=1, pixel_ratio=1.0, cam_x=0.0, cam_y=0.0, point_x=0.0, point_y=0.0)
+@example(vp_width=2, vp_height=2, pixel_ratio=1.0, cam_x=0.0, cam_y=0.0, point_x=0.0, point_y=0.0)
 def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y, point_x, point_y):
     cam = Camera(
         viewport=(0, 0, vp_width, vp_height),
@@ -123,7 +123,7 @@ def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y
 
     point_viewport = cam.translate_to_viewport(point)
     note(f"point->viewport: {point_viewport}")
-    point_frame = cam.translate_to_viewport(point_viewport)
+    point_frame = cam.translate_to_frame(point_viewport)
     note(f"point->viewport->frame: {point_frame}")
     assert point_frame.isclose(point, rel_tol=1e-5)
 

From 80270cc6f5525ad8f3b631dc1484c3b30f1df149 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Fri, 24 May 2019 14:34:04 -0400
Subject: [PATCH 14/15] Camera: Vectorize the the tests

---
 tests/test_camera.py | 39 +++++++++++++++------------------------
 tests/utils.py       | 11 +++++++++++
 2 files changed, 26 insertions(+), 24 deletions(-)
 create mode 100644 tests/utils.py

diff --git a/tests/test_camera.py b/tests/test_camera.py
index 43cad3f6..714ce5b6 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -6,6 +6,7 @@
 
 from hypothesis import given, assume, note, example
 import hypothesis.strategies as st
+from .utils import vectors
 
 
 def test_camera_move():
@@ -94,25 +95,23 @@ def test_viewport_change_affects_frame_height():
     vp_width=st.integers(min_value=1),
     vp_height=st.integers(min_value=1),
     pixel_ratio=st.floats(min_value=1, max_value=1e5, allow_nan=False, allow_infinity=False),
-    cam_x=st.floats(allow_nan=False, allow_infinity=False),
-    cam_y=st.floats(allow_nan=False, allow_infinity=False),
-    point_x=st.floats(allow_nan=False, allow_infinity=False),
-    point_y=st.floats(allow_nan=False, allow_infinity=False),
+    cam_pos=vectors(),
+    point=vectors(),
 )
-@example(vp_width=2, vp_height=2, pixel_ratio=1.0, cam_x=0.0, cam_y=0.0, point_x=0.0, point_y=0.0)
-def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y, point_x, point_y):
+@example(vp_width=2, vp_height=2, pixel_ratio=1.0, cam_pos=Vector(0.0, 0.0), point=Vector(0.0, 0.0))
+def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_pos, point):
     cam = Camera(
         viewport=(0, 0, vp_width, vp_height),
         pixel_ratio=pixel_ratio,
     )
-    cam.position = Vector(cam_x, cam_y)
-    point = Vector(point_x, point_y)
+    cam.position = cam_pos
+
+    note(f"frame: ({cam.frame_left}, {cam.frame_bottom}) -> ({cam.frame_right}, {cam.frame_top})")
 
     # Some underflow/loss of resolution problems
     assume(cam.frame_left != cam.frame_right)
     assume(cam.frame_top != cam.frame_bottom)
 
-    note(f"frame: ({cam.frame_left}, {cam.frame_bottom}) -> ({cam.frame_right}, {cam.frame_top})")
     note(f"point: {point}")
 
     point_frame = cam.translate_to_frame(point)
@@ -132,26 +131,18 @@ def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_x, cam_y
     vp_width=st.integers(min_value=1),
     vp_height=st.integers(min_value=1),
     pixel_ratio=st.floats(min_value=1, max_value=1e5, allow_nan=False, allow_infinity=False),
-    cam_x=st.floats(allow_nan=False, allow_infinity=False),
-    cam_y=st.floats(allow_nan=False, allow_infinity=False),
-    point_x=st.floats(allow_nan=False, allow_infinity=False),
-    point_y=st.floats(allow_nan=False, allow_infinity=False),
-    delta_x=st.floats(allow_nan=False, allow_infinity=False),
-    delta_y=st.floats(allow_nan=False, allow_infinity=False),
+    cam_pos=vectors(),
+    point=vectors(),
+    delta=vectors(),
 )
 def test_transfromation_movement(
-    vp_width, vp_height, pixel_ratio, cam_x, cam_y, point_x, point_y, delta_x, delta_y,
+    vp_width, vp_height, pixel_ratio, cam_pos, point, delta,
 ):
     cam = Camera(
         viewport=(0, 0, vp_width, vp_height),
         pixel_ratio=pixel_ratio,
     )
-    cam.position = Vector(cam_x, cam_y)
-    point = Vector(point_x, point_y)
-    delta = Vector(delta_x, delta_y)
-
-    note(f"point: {point}")
-    note(f"delta: {delta}")
+    cam.position = cam_pos
 
     assume(delta.length != 0)
 
@@ -163,7 +154,7 @@ def test_transfromation_movement(
 
     diff = cam.translate_to_frame(point_moved) - cam.translate_to_frame(point)
     note(f"frame diff: {diff}")
-    assert isclose(delta.length / diff.length, pixel_ratio, rel_tol=1e-5)
+    assert isclose(delta.length, pixel_ratio * diff.length, rel_tol=1e-5)
     diff = cam.translate_to_viewport(point_moved) - cam.translate_to_viewport(point)
     note(f"viewport diff: {diff}")
-    assert isclose(diff.length / delta.length, pixel_ratio, rel_tol=1e-5)
+    assert isclose(diff.length, pixel_ratio * delta.length, rel_tol=1e-5)
diff --git a/tests/utils.py b/tests/utils.py
new file mode 100644
index 00000000..bda9bda0
--- /dev/null
+++ b/tests/utils.py
@@ -0,0 +1,11 @@
+import hypothesis.strategies as st
+
+from ppb import Vector
+
+
+def vectors(max_magnitude=1e75):
+    return st.builds(
+        Vector,
+        st.floats(min_value=-max_magnitude, max_value=max_magnitude),
+        st.floats(min_value=-max_magnitude, max_value=max_magnitude),
+    )

From 0af8e5f684c85e570f742d4936b1471a8dcf7285 Mon Sep 17 00:00:00 2001
From: Jamie Bliss <jamie@ivyleav.es>
Date: Fri, 24 May 2019 15:13:12 -0400
Subject: [PATCH 15/15] Camera: Reduce the magnitude of camera position in
 testing, to prevent precision problems.

---
 tests/test_camera.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/tests/test_camera.py b/tests/test_camera.py
index 714ce5b6..17cc60e1 100644
--- a/tests/test_camera.py
+++ b/tests/test_camera.py
@@ -95,7 +95,7 @@ def test_viewport_change_affects_frame_height():
     vp_width=st.integers(min_value=1),
     vp_height=st.integers(min_value=1),
     pixel_ratio=st.floats(min_value=1, max_value=1e5, allow_nan=False, allow_infinity=False),
-    cam_pos=vectors(),
+    cam_pos=vectors(1e15),  # Set low to prevent loss-of-precision problems about frame size
     point=vectors(),
 )
 @example(vp_width=2, vp_height=2, pixel_ratio=1.0, cam_pos=Vector(0.0, 0.0), point=Vector(0.0, 0.0))
@@ -108,7 +108,7 @@ def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_pos, poi
 
     note(f"frame: ({cam.frame_left}, {cam.frame_bottom}) -> ({cam.frame_right}, {cam.frame_top})")
 
-    # Some underflow/loss of resolution problems
+    # Some underflow/loss of precision problems
     assume(cam.frame_left != cam.frame_right)
     assume(cam.frame_top != cam.frame_bottom)
 
@@ -118,13 +118,13 @@ def test_transfromation_roundtrip(vp_width, vp_height, pixel_ratio, cam_pos, poi
     note(f"point->frame: {point_frame}")
     point_viewport = cam.translate_to_viewport(point_frame)
     note(f"point->frame->viewport: {point_viewport}")
-    assert point_viewport.isclose(point, rel_tol=1e-5)
+    assert point_viewport.isclose(point, rel_tol=1e-5, rel_to=[cam.position])
 
     point_viewport = cam.translate_to_viewport(point)
     note(f"point->viewport: {point_viewport}")
     point_frame = cam.translate_to_frame(point_viewport)
     note(f"point->viewport->frame: {point_frame}")
-    assert point_frame.isclose(point, rel_tol=1e-5)
+    assert point_frame.isclose(point, rel_tol=1e-5, rel_to=[cam.position])
 
 
 @given(