generalize norm conversion code

1 files changed, 10 insertions, 13 deletions

diff --git a/vertex_deformation.slang b/vertex_deformation.slang
index 5337e8a..1af5ec9 100644
--- a/vertex_deformation.slang
+++ b/vertex_deformation.slang
@@ -171,25 +171,22 @@ public void sine_wave_undeform_normal(float3 xyz, inout float3 normal,
   R3R3_UNDEFORM_NORMAL_AND_TANGENT(normal, tangent);
 }
 
-// Map from l2 (euclidean) norm to l-infinity (supremum, max) norm.
 [Differentiable]
-public float3 l2_to_linf(float3 xyz, no_diff float t) {
-  float l2 = length(xyz);
-  float3 abs_xyz = abs(xyz);
-  float linf = max(abs_xyz.x, max(abs_xyz.y, abs_xyz.z));
-
-  float scale = lerp(1.0f, linf / l2, t);
-
+public float3 norm_conversion(float3 xyz, no_diff float input_k, no_diff float output_k, no_diff float t) {
+  float3 xyz_abs = abs(xyz)+1e-3f;
+  float lin = pow(pow(xyz_abs.x, input_k) + pow(xyz_abs.y, input_k) + pow(xyz_abs.z, input_k), 1.0f / input_k);
+  float lout = pow(pow(xyz_abs.x, output_k) + pow(xyz_abs.y, output_k) + pow(xyz_abs.z, output_k), 1.0f / output_k);
+  float scale = lerp(1.0f, lout / lin, t);
   return xyz * scale;
 }
 
-public void l2_to_linf_normal(float3 xyz, inout float3 normal, inout float3 tangent, float t) {
-  R3R3_NORMALS(xyz, normal, tangent, l2_to_linf, t);
+public void norm_conversion_normal(inout float3 xyz, inout float3 normal, inout float3 tangent, float input_k, float output_k, float t) {
+  R3R3_NORMALS(xyz, normal, tangent, norm_conversion, input_k, output_k, t);
 }
 
-public void l2_to_linf_undeform_normal(float3 xyz, inout float3 normal, inout float3 tangent, float t) {
+public void norm_conversion_undeform_normal(float3 xyz, inout float3 normal, inout float3 tangent, float input_k, float output_k, float t) {
   R3R3_DECLARE_BASIS_VECTORS(xyz);
-  R3R3_AUTODIFF_BASIS_VECTORS(l2_to_linf, t);
+  R3R3_AUTODIFF_BASIS_VECTORS(norm_conversion, input_k, output_k, t);
   R3R3_UNDEFORM_NORMAL_AND_TANGENT(normal, tangent);
 }
 
@@ -200,7 +197,7 @@ float3 rand3_hash3(float3 p)
     p = float3(dot(p, float3(127.1, 311.7, 74.7)),
                dot(p, float3(269.5, 183.3, 246.1)),
                dot(p, float3(113.5, 271.9, 124.6)));
-    return frac(sin(p) * 43758.5453123);
+    return frac(sin(p) * 43758.5453123)*2-1;
 }
 
 [Differentiable]