add l2 -> l infinity norm deformation

1 files changed, 11 insertions, 12 deletions

diff --git a/ray_marching_maps.slang b/ray_marching_maps.slang
index 87481a0..3c83a19 100644
--- a/ray_marching_maps.slang
+++ b/ray_marching_maps.slang
@@ -14,9 +14,9 @@
   DifferentialPair<float3> dp_z = diffPair(xyz, float3(0, 0, 1))
 
 #define R3R1_AUTODIFF_BASIS_VECTORS(fun, ...) \
-  DifferentialPair<float> dp_x_out = fwd_diff(fun)(dp_x, ##__VA_ARGS__); \
-  DifferentialPair<float> dp_y_out = fwd_diff(fun)(dp_y, ##__VA_ARGS__); \
-  DifferentialPair<float> dp_z_out = fwd_diff(fun)(dp_z, ##__VA_ARGS__)
+  DifferentialPair<float> dp_x_out = fwd_diff(fun)(dp_x, __VA_ARGS__); \
+  DifferentialPair<float> dp_y_out = fwd_diff(fun)(dp_y, __VA_ARGS__); \
+  DifferentialPair<float> dp_z_out = fwd_diff(fun)(dp_z, __VA_ARGS__)
 
 #define R3R1_DEFORM_NORMAL_AND_TANGENT(normal, tangent) \
   { \
@@ -29,29 +29,28 @@
 // Syntactic sugar - wraps the previous three macros.
 #define R3R1_RAY_MARCH_NORMALS(xyz, normal, tangent, fun, ...)  \
   R3R1_DECLARE_BASIS_VECTORS(xyz);                              \
-  R3R1_AUTODIFF_BASIS_VECTORS(fun, ##__VA_ARGS__);              \
+  R3R1_AUTODIFF_BASIS_VECTORS(fun, __VA_ARGS__);              \
   R3R1_DEFORM_NORMAL_AND_TANGENT(normal, tangent)
 
 // Just trace a sphere of radius 0.1 for now.
 [Differentiable]
-public float map(float3 p) {
-  float3 count = float3(20,20,1);
-  float3 period = 0.05f;
+public float map_ball_grid(float3 p, no_diff float3 count) {
+  float3 period = 1.0f / count;
+  period *= 2;
   float3 half_period = period*0.5f;
-  float3 which = abs(floor((p + half_period) / period));
-  if (any(abs(which) >= count)) {
+  float3 which = floor((p + half_period) / period);
+  if (any(abs(which) > count/2)) {
     p = 1e6;
   } else {
     p = glsl_mod(p + half_period, period) - half_period;
   }
 
-  p.z += half_period.x;
   return length(p) - half_period.x;
 }
 
-public void map_normal(inout float3 xyz, inout float3 normal,
+public void map_ball_grid_normal(float3 count, inout float3 xyz, inout float3 normal,
     inout float3 tangent) {
-  R3R1_RAY_MARCH_NORMALS(xyz, normal, tangent, map);
+  R3R1_RAY_MARCH_NORMALS(xyz, normal, tangent, map_ball_grid, count);
 }
 
 #endif  // __RAY_MARCHING_MAPS_INC