Snap rooms to the grid

1 files changed, 18 insertions, 0 deletions

diff --git a/src/math.rs b/src/math.rs
index c4e7ac0..60a53e8 100644
--- a/src/math.rs
+++ b/src/math.rs
@@ -16,3 +16,21 @@ pub fn bounding_rect(pos1: Vector2, pos2: Vector2) -> Rectangle {
         height: max_y - min_y,
     }
 }
+
+/// Round a floating point number to the nearest step given by the step argument. For instance, if
+/// the step is 0.5, then all numbers from 0.0 to 0.24999... will be 0., while all numbers from
+/// 0.25 to 0.74999... will be 0.5 and so on.
+pub fn round(num: f32, step: f32) -> f32 {
+    // Only positive steps will be accepted.
+    assert!(step > 0.);
+
+    let lower_bound = ((num / step) as i32) as f32 * step;
+    let upper_bound = lower_bound + step;
+
+    // Compare the distances and prefer the smaller. If they are the same, prefer the upper bound.
+    if (num - lower_bound) < (upper_bound - num) {
+        lower_bound
+    } else {
+        upper_bound
+    }
+}