arst

src/client/camera.rs

@@ -0,0 +1,59 @@
+use nalgebra::Vector2;
+use std::ops::AddAssign;
+
+use crate::util::FixedDec;
+
+#[derive(Clone, Copy)]
+pub struct Zoom {
+    scale: f32,
+    mult: f32,
+}
+
+#[derive(Clone)]
+pub struct Camera {
+    pub pos: Vector2<FixedDec>,
+    pub zoom: Zoom,
+}
+
+impl Camera {
+    pub fn scale(&self, size: &Vector2<u32>) -> Vector2<f32> {
+        let fsize: Vector2<f32> = size.cast();
+        if size.x < size.y {
+            Vector2::new(fsize.x / fsize.y, 1.0)
+        } else {
+            Vector2::new(1.0, fsize.y / fsize.x)
+        }
+    }
+}
+
+impl Default for Camera {
+    fn default() -> Self {
+        Self {
+            pos: Vector2::zeros(),
+            zoom: Zoom::new(0.0),
+        }
+    }
+}
+
+impl Zoom {
+    pub fn new(scale: f32) -> Self {
+        Self {
+            scale,
+            mult: mult(scale),
+        }
+    }
+    pub fn mult(&self) -> f32 {
+        self.mult
+    }
+}
+
+impl AddAssign<f32> for Zoom {
+    fn add_assign(&mut self, rhs: f32) {
+        self.scale += rhs;
+        self.mult = mult(self.scale);
+    }
+}
+
+pub fn mult(scale: f32) -> f32 {
+    (-scale).exp2()
+}