Subtract the central sphere, and update the animation to match

1 files changed, 3 insertions, 1 deletions

diff --git a/3dmath.h b/3dmath.h
index 3a984cb..1635c40 100644
--- a/3dmath.h
+++ b/3dmath.h
@@ -1,6 +1,8 @@
+#define POW2(x) ((x) * (x))
+
 float dot(const float x[3], const float y[3]);
 void normalize(float x[3]);
 
 float sphere_intersect(float* restrict y, float* restrict r,
                        const float* restrict s, const float* restrict d,
-                       const float* restrict c, float R);
+                       const float* restrict c, float R, int invert);