feat(engine): add projection options to camera component

1 files changed, 46 insertions, 10 deletions

diff --git a/engine/src/projection.rs b/engine/src/projection.rs
index d5186ba..aa84a9f 100644
--- a/engine/src/projection.rs
+++ b/engine/src/projection.rs
@@ -1,20 +1,56 @@
 use crate::matrix::Matrix;
 
-/// Creates a new perspective projection matrix.
-#[must_use]
-pub fn new_perspective(
-    fov_radians: f32,
+#[derive(Debug)]
+#[non_exhaustive]
+pub enum Projection
+{
+    Perspective(Perspective),
+}
+
+/// Perspective projection parameters.
+#[derive(Debug)]
+pub struct Perspective
+{
+    pub fov_radians: f32,
+    pub far: f32,
+    pub near: f32,
+}
+
+impl Default for Perspective
+{
+    fn default() -> Self
+    {
+        Self {
+            fov_radians: 80.0f32.to_radians(),
+            far: 100.0,
+            near: 0.1,
+        }
+    }
+}
+
+pub(crate) fn new_perspective_matrix(
+    perspective: &Perspective,
     aspect: f32,
-    far: f32,
-    near: f32,
 ) -> Matrix<f32, 4, 4>
 {
     let mut out = Matrix::new();
 
-    out.set_cell(0, 0, (1.0 / (fov_radians / 2.0).tan()) / aspect);
-    out.set_cell(1, 1, 1.0 / (fov_radians / 2.0).tan());
-    out.set_cell(2, 2, (near + far) / (near - far));
-    out.set_cell(2, 3, (2.0 * near * far) / (near - far));
+    out.set_cell(0, 0, (1.0 / (perspective.fov_radians / 2.0).tan()) / aspect);
+
+    out.set_cell(1, 1, 1.0 / (perspective.fov_radians / 2.0).tan());
+
+    out.set_cell(
+        2,
+        2,
+        (perspective.near + perspective.far) / (perspective.near - perspective.far),
+    );
+
+    out.set_cell(
+        2,
+        3,
+        (2.0 * perspective.near * perspective.far) / (perspective.near - perspective.far),
+    );
+
     out.set_cell(3, 2, -1.0);
 
     out