Merge branch 'master' into immutable-vectors

ppb · May 5, 2019 · 8c28091 · 8c28091
2 parents 4060e2c + 7498600
commit 8c28091
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Showing 10 changed files with 44 additions and 10 deletions.
diff --git a/examples/animated_sprite.py b/examples/animated_sprite.py
@@ -0,0 +1,26 @@
+import math
+
+import ppb
+from ppb.features.animation import Animation
+import ppb.events as events
+
+
+class Blob(ppb.BaseSprite):
+    image = Animation("./resources/blob_{0..6}.png", 10)
+    target = ppb.Vector(0, 0)
+    speed = 1
+
+    def on_mouse_motion(self, event: events.MouseMotion, signal):
+        self.target = event.position
+
+    def on_update(self, event: events.Update, signal):
+        intent_vector = self.target - self.position
+        self.position += intent_vector.scale(self.speed * event.time_delta)
+        self.rotation = math.degrees(math.atan2(intent_vector.y, intent_vector.x)) + 90
+
+
+def setup(scene):
+    scene.add(Blob())
+
+
+ppb.run(setup)
diff --git a/examples/resources/blob_0.png b/examples/resources/blob_0.png
diff --git a/examples/resources/blob_1.png b/examples/resources/blob_1.png
diff --git a/examples/resources/blob_2.png b/examples/resources/blob_2.png
diff --git a/examples/resources/blob_3.png b/examples/resources/blob_3.png
diff --git a/examples/resources/blob_4.png b/examples/resources/blob_4.png
diff --git a/examples/resources/blob_5.png b/examples/resources/blob_5.png
diff --git a/examples/resources/blob_6.png b/examples/resources/blob_6.png
diff --git a/ppb/camera.py b/ppb/camera.py
@@ -96,10 +96,18 @@ def in_frame(self, sprite: BaseSprite) -> bool:
                 self.frame_bottom >= sprite.top
                 )
 
-    def translate_to_frame(self, point:Vector) -> Vector:
+    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)
-        return self.position + offset
+        loc = self.position + offset
+        return loc.update(y=-loc.y)
 
-    def translate_to_viewport(self, point:Vector) -> Vector:
+    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
diff --git a/tests/test_camera.py b/tests/test_camera.py
@@ -30,20 +30,20 @@ def test_camera_translate_to_frame():
     cam = Camera(viewport=(0, 0, 800, 600), pixel_ratio=80)
     assert cam.position == Vector(0, 0)
     assert cam.translate_to_frame(Vector(400, 300)) == Vector(0, 0)
-    assert cam.translate_to_frame(Vector(560, 220)) == Vector(2, -1)
+    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, -4)
 
 
 def test_camera_translate_to_viewport():
     cam = Camera(viewport=(0, 0, 800, 600), pixel_ratio=80)
     assert cam.position == Vector(0, 0)
     assert cam.translate_to_viewport(Vector(0, 0)) == Vector(400, 300)
-    assert cam.translate_to_viewport(Vector(2, -1)) == Vector(560, 220)
+    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, 220)
 
 
 def test_sprite_in_viewport():
@@ -70,4 +70,4 @@ def test_viewport_change_affects_frame_height():
     cam = Camera(viewport=(0, 0, 800, 600), pixel_ratio=80)
     assert cam.frame_left == -5
     cam.viewport_width = 400
-    assert cam.frame_left == -2.5
+    assert cam.frame_left == -2.5