fix!:make matrix z rotation go clockwise instead of ccw

I yolo'd this by just swapping the signs and it seemed to work, but if
there were suddenly weird issues with rotation, I would look here.

1 files changed, 6 insertions, 2 deletions

diff --git a/src/matrix.zig b/src/matrix.zig
index 355369e..8ce1dfc 100644
--- a/src/matrix.zig
+++ b/src/matrix.zig
@@ -81,12 +81,16 @@ pub fn Matrix(comptime T: type, row_count: usize, col_count: usize) type {
             const s = @sin(angle);
             var base = Self.identity;
             base.data[0][0] = c;
-            base.data[0][1] = -s;
-            base.data[1][0] = s;
+            base.data[0][1] = s;
+            base.data[1][0] = -s;
             base.data[1][1] = c;
             return base;
         }
 
+        pub fn rotateZ(self: Self, angle: T) Self {
+            return self.multiply(Self.zRotation(angle));
+        }
+
         pub fn scaled(self: Self, vals: [@min(rows, cols) - 1]f32) Self {
             return self.multiply(Self.scale(vals));
         }