updated ViewportProjector to use Rect, and created unit tests (#2343)

* updated ViewportProjector to use Rect and created unit tests

* linting ✨

* ⬛

* Correcting references to the viewport

Thanks for pointing out the issue, @eruvanos!

arcade/camera/default.py

@@ -6,7 +6,7 @@
 from pyglet.math import Mat4, Vec2, Vec3
 from typing_extensions import Self
 
-from arcade.types import Point
+from arcade.types import LBWH, Point, Rect
 from arcade.window_commands import get_window
 
 if TYPE_CHECKING:
@@ -29,28 +29,28 @@ class ViewportProjector:
 
     def __init__(
         self,
-        viewport: tuple[int, int, int, int] | None = None,
+        viewport: Rect | None = None,
         *,
         context: ArcadeContext | None = None,
     ):
-        self._ctx = context or get_window().ctx
-        self._viewport = viewport or self._ctx.viewport
+        self._ctx: ArcadeContext = context or get_window().ctx
+        self._viewport: Rect = viewport or LBWH(*self._ctx.viewport)
         self._projection_matrix: Mat4 = Mat4.orthogonal_projection(
-            0.0, self._viewport[2], 0.0, self._viewport[3], -100, 100
+            0.0, self._viewport.width, 0.0, self._viewport.height, -100, 100
         )
 
     @property
-    def viewport(self) -> tuple[int, int, int, int]:
+    def viewport(self) -> Rect:
         """
         The viewport use to derive projection and view matrix.
         """
         return self._viewport
 
     @viewport.setter
-    def viewport(self, viewport: tuple[int, int, int, int]) -> None:
+    def viewport(self, viewport: Rect) -> None:
         self._viewport = viewport
         self._projection_matrix = Mat4.orthogonal_projection(
-            0, viewport[2], 0, viewport[3], -100, 100
+            0, viewport.width, 0, viewport.height, -100, 100
         )
 
     def use(self) -> None:
@@ -60,7 +60,7 @@ def use(self) -> None:
         """
         self._ctx.current_camera = self
 
-        self._ctx.viewport = self._viewport
+        self._ctx.viewport = self.viewport.viewport  # get the integer 4-tuple LBWH
 
         self._ctx.view_matrix = Mat4()
         self._ctx.projection_matrix = self._projection_matrix
@@ -121,18 +121,19 @@ def use(self) -> None:
         cache's the window viewport to determine the projection matrix.
         """
 
+        viewport = self.viewport.viewport
         # If the viewport is correct and the default camera is in use,
         # then don't waste time resetting the view and projection matrices
-        if self._ctx.viewport == self.viewport and self._ctx.current_camera == self:
+        if self._ctx.viewport == viewport and self._ctx.current_camera == self:
             return
 
         # If the viewport has changed while the default camera is active then the
         # default needs to update itself.
         # If it was another camera's viewport being used the default camera should not update.
-        if self._ctx.viewport != self.viewport and self._ctx.current_camera == self:
-            self.viewport = self._ctx.viewport
+        if self._ctx.viewport != viewport and self._ctx.current_camera == self:
+            self.viewport = LBWH(*self._ctx.viewport)
         else:
-            self._ctx.viewport = self.viewport
+            self._ctx.viewport = viewport
 
         self._ctx.current_camera = self
 

tests/unit/camera/test_viewport_projector.py

@@ -0,0 +1,25 @@
+import pytest as pytest
+
+from pyglet.math import Vec3, Vec2
+
+from arcade import camera, Window
+from arcade.types import Point, LBWH, Rect
+
+@pytest.mark.parametrize("wrld_pos", [Vec2(100, 150), Vec2(1280, 720), Vec3(500, 500, -10)])
+def test_viewport_projector_project(window: Window, wrld_pos: Point):
+    cam = camera.default.ViewportProjector()
+    assert cam.project(wrld_pos) == wrld_pos.xy
+
+@pytest.mark.parametrize("wrld_pos", [Vec2(100, 150), Vec2(1280, 720), Vec3(500, 500, -10)])
+def test_viewport_projector_unproject(window: Window, wrld_pos: Point):
+    cam = camera.default.ViewportProjector()
+    x, y, *z = wrld_pos
+
+    assert cam.unproject(wrld_pos) == Vec3(x, y, 0.0 if not z else z[0])
+
+@pytest.mark.parametrize("viewport", [LBWH(0.0, 0.0, 100, 200), LBWH(100, 100, 20, 40), LBWH(300, 20, 20, 700)])
+def test_viewport_projector_viewport(window: Window, viewport: Rect):
+    cam = camera.default.ViewportProjector()
+    assert cam.viewport.viewport == window.ctx.viewport
+    cam.viewport = viewport
+    assert cam.viewport == viewport