meow

4 files changed, 165 insertions, 7 deletions

diff --git a/features.cginc b/features.cginc
index 4547929..b5c7e64 100644
--- a/features.cginc
+++ b/features.cginc
@@ -70,10 +70,6 @@
 
 //ifex _Ray_Marching_Enabled==0
 #pragma shader_feature_local _RAY_MARCHING
-#if defined(_RAY_MARCHING)
-#undef _VERTEX_DEFORMATION_FRAGMENT_NORMALS
-#undef _VERTEX_DEFORMATION_TESSELLATION
-#endif
 //endex
 
 //ifex _Ray_Marching_Baked_Origins_Enabled==0
diff --git a/ray_marching.cginc b/ray_marching.cginc
index 9c6653f..1efbdf4 100644
--- a/ray_marching.cginc
+++ b/ray_marching.cginc
@@ -32,8 +32,8 @@ RayMarchResult ray_march(v2f i) {
   float3 rd_perp = i.normal * dot(i.normal, rd);
   float3 rd_tan  = rd - rd_perp;
   float3 tmp = ro;
-  deform_normal(tmp, rd_perp, rd_tan);
-  rd = rd_perp + rd_tan;
+  undeform_normal(ro, rd_perp, rd_tan);
+  //rd = rd_perp + rd_tan;
 #endif
 
   const float kMinDist = 1e-3;
diff --git a/vertex.cginc b/vertex.cginc
index 303fc00..cd3382c 100644
--- a/vertex.cginc
+++ b/vertex.cginc
@@ -178,7 +178,129 @@ void deform_normal(inout float3 objPos, inout float3 objNorm, inout float3 objTa
 //  3. Repeat step 2 until we're back in the un-deforme coordinate system. At
 //     each step, we use the cached objPos from the forward pass (step 1), so
 //     that we evaluate the normal deformation at the correct point in space.
-void undeform_normal(float3 objPos, inout float3 objNorm, inout float3 objTan) {
+void undeform_normal(inout float3 objPos, inout float3 objNorm, inout float3 objTan) {
+  const float t = getTime();
+  const int kMaxDeformations = 8;
+  // Cache each intermediate position so we can undo stages in reverse order.
+  float3 posHistory[kMaxDeformations + 1];
+  int posCount = 0;
+  posHistory[posCount++] = objPos;
+
+#if defined(_VERTEX_DEFORMATION_XZ_TUBE)
+  {
+    VERTEX_DEFORM_XZ_TUBE_PREAMBLE;
+    VERTEX_DEFORM_XZ_TUBE_POS;
+    posHistory[posCount++] = objPos;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_YZ_TUBE)
+  {
+    VERTEX_DEFORM_YZ_TUBE_PREAMBLE;
+    VERTEX_DEFORM_YZ_TUBE_POS;
+    posHistory[posCount++] = objPos;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_XY_TUBE)
+  {
+    VERTEX_DEFORM_XY_TUBE_PREAMBLE;
+    VERTEX_DEFORM_XY_TUBE_POS;
+    posHistory[posCount++] = objPos;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_SEAL)
+  {
+    VERTEX_DEFORM_SEAL_PREAMBLE;
+    VERTEX_DEFORM_SEAL_POS;
+    posHistory[posCount++] = objPos;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_SINE_WAVES)
+  {
+    VERTEX_DEFORM_SINE_WAVES_PREAMBLE;
+    VERTEX_DEFORM_SINE_WAVES_POS;
+    posHistory[posCount++] = objPos;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_FBM)
+  {
+    VERTEX_DEFORM_FBM_PREAMBLE;
+    VERTEX_DEFORM_FBM_POS;
+    posHistory[posCount++] = objPos;
+  }
+#endif
+  float3 objPos_deformed = objPos;
+
+  int cursor = posCount - 1;
+  objPos = posHistory[cursor];
+
+#if defined(_VERTEX_DEFORMATION_FBM)
+  if (cursor > 0) {
+    VERTEX_DEFORM_FBM_PREAMBLE;
+    float3 stageInput = posHistory[cursor - 1];
+    fbm_undeform_normal(stageInput, st, amplitude, gain, lacunarity, scale,
+        octaves, velocity, objNorm, objTan);
+    objPos = stageInput;
+    cursor -= 1;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_SINE_WAVES)
+  if (cursor > 0) {
+    VERTEX_DEFORM_SINE_WAVES_PREAMBLE;
+    float3 stageInput = posHistory[cursor - 1];
+    sine_wave_undeform_normal(stageInput, objNorm, objTan, amplitude, direction,
+        k, omega, st);
+    objPos = stageInput;
+    cursor -= 1;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_SEAL)
+  if (cursor > 0) {
+    VERTEX_DEFORM_SEAL_PREAMBLE;
+    float3 stageInput = posHistory[cursor - 1];
+    seal_undeform_normal(stageInput, objNorm, objTan, A, k, st);
+    objPos = stageInput;
+    cursor -= 1;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_XY_TUBE)
+  if (cursor > 0) {
+    VERTEX_DEFORM_XY_TUBE_PREAMBLE;
+    float3 stageInput = posHistory[cursor - 1];
+    float3 xyPos = stageInput.xzy;
+    float3 xyNorm = objNorm.xzy;
+    float3 xyTan = objTan.xzy;
+    plane_to_tube_undeform_normal(xyPos, xyNorm, xyTan, t);
+    objNorm = xyNorm.xzy;
+    objTan = xyTan.xzy;
+    objPos = stageInput;
+    cursor -= 1;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_YZ_TUBE)
+  if (cursor > 0) {
+    VERTEX_DEFORM_YZ_TUBE_PREAMBLE;
+    float3 stageInput = posHistory[cursor - 1];
+    float3 yzPos = stageInput.yxz;
+    float3 yzNorm = objNorm.yxz;
+    float3 yzTan = objTan.yxz;
+    plane_to_tube_undeform_normal(yzPos, yzNorm, yzTan, t);
+    objNorm = yzNorm.yxz;
+    objTan = yzTan.yxz;
+    objPos = stageInput;
+    cursor -= 1;
+  }
+#endif
+#if defined(_VERTEX_DEFORMATION_XZ_TUBE)
+  if (cursor > 0) {
+    VERTEX_DEFORM_XZ_TUBE_PREAMBLE;
+    float3 stageInput = posHistory[cursor - 1];
+    plane_to_tube_undeform_normal(stageInput, objNorm, objTan, t);
+    objPos = stageInput;
+    cursor -= 1;
+  }
+#endif
+
+  objPos = objPos_deformed;
 }
 
 void propagateObjPos(inout v2f i) {
diff --git a/vertex_deformation.slang b/vertex_deformation.slang
index 63804de..678cc24 100644
--- a/vertex_deformation.slang
+++ b/vertex_deformation.slang
@@ -107,6 +107,13 @@ public void plane_to_tube_normal(inout float3 xyz, inout float3 normal,
   R3R3_NORMALS(xyz, normal, tangent, plane_to_tube, t);
 }
 
+public void plane_to_tube_undeform_normal(float3 xyz, inout float3 normal,
+    inout float3 tangent, float t) {
+  R3R3_DECLARE_BASIS_VECTORS(xyz);
+  R3R3_AUTODIFF_BASIS_VECTORS(plane_to_tube, t);
+  R3R3_UNDEFORM_NORMAL_AND_TANGENT(normal, tangent);
+}
+
 [Differentiable]
 public float3 seal(float3 xyz, no_diff float A, no_diff float k, no_diff float t) {
   float x = xyz.x;
@@ -133,6 +140,13 @@ public void seal_normal(inout float3 xyz, inout float3 normal,
   R3R3_NORMALS(xyz, normal, tangent, seal, A, k, t);
 }
 
+public void seal_undeform_normal(float3 xyz, inout float3 normal,
+    inout float3 tangent, float A, float k, float t) {
+  R3R3_DECLARE_BASIS_VECTORS(xyz);
+  R3R3_AUTODIFF_BASIS_VECTORS(seal, A, k, t);
+  R3R3_UNDEFORM_NORMAL_AND_TANGENT(normal, tangent);
+}
+
 [Differentiable]
 public float3 sine_wave(float3 xyz,
     no_diff float3 amplitude,
@@ -149,6 +163,14 @@ public void sine_wave_normal(inout float3 xyz, inout float3 normal, inout float3
   R3R3_NORMALS(xyz, normal, tangent, sine_wave, amplitude, direction, k, omega, t);
 }
 
+public void sine_wave_undeform_normal(float3 xyz, inout float3 normal,
+    inout float3 tangent, float3 amplitude, float3 direction, float3 k,
+    float3 omega, float t) {
+  R3R3_DECLARE_BASIS_VECTORS(xyz);
+  R3R3_AUTODIFF_BASIS_VECTORS(sine_wave, amplitude, direction, k, omega, t);
+  R3R3_UNDEFORM_NORMAL_AND_TANGENT(normal, tangent);
+}
+
 [Differentiable]
 float3 rand3_hash3(float3 p)
 {
@@ -292,4 +314,22 @@ public void fbm_normal(inout float3 xyz, inout float3 normal, inout float3 tange
   tangent = mul(jac, tangent);
 }
 
+public void fbm_undeform_normal(float3 xyz, float t,
+    float amplitude, float gain, float lacunarity,
+    float scale, float octaves, float3 velocity,
+    inout float3 normal, inout float3 tangent) {
+  float3 dx, dy, dz;
+  fbm_with_derivatives(xyz, t, amplitude, gain, lacunarity, scale, octaves,
+      velocity, dx, dy, dz);
+  float3x3 jac = float3x3(
+      dx.x, dy.x, dz.x,
+      dx.y, dy.y, dz.y,
+      dx.z, dy.z, dz.z);
+  float jac_det = determinant(jac);
+  float3x3 inv_jac = inverse(jac, jac_det);
+  float3x3 trans_jac = transpose(jac);
+  normal = mul(trans_jac, normal) * sign(jac_det);
+  tangent = mul(inv_jac, tangent);
+}
+
 #endif  // __CUSTOM31_INC