adjust ray marching loop structure

3 files changed, 81 insertions, 62 deletions

diff --git a/3ner.shader b/3ner.shader
index a6c8af4..9315aed 100644
--- a/3ner.shader
+++ b/3ner.shader
@@ -64,10 +64,16 @@ Shader "yum_food/3ner"
           //ifex _Ray_Marching_Overstepping_Enabled==0
           [HideInInspector] m_start_Ray_Marching_Overstepping("Overstepping", Float) = 0
             [ThryToggle(_RAY_MARCHING_OVERSTEP)] _Ray_Marching_Overstepping_Enabled("Enable", Float) = 0
-            _Ray_Marching_Overstepping_Factor("Factor", Range(1,2)) = 1.3
+            _Ray_Marching_Overstepping_Factor("Factor", Range(1,5)) = 1.3
           [HideInInspector] m_end_Ray_Marching_Overstepping("Overstepping", Float) = 0
           //endex
 
+          //ifex _Ray_Marching_Correct_Repetition_Enabled==0
+          [HideInInspector] m_start_Ray_Marching_Correct_Repetition("Correct Repetition", Float) = 0
+            [ThryToggle(_RAY_MARCHING_CORRECT_REPETITION)] _Ray_Marching_Correct_Repetition_Enabled("Enable", Float) = 0
+          [HideInInspector] m_end_Ray_Marching_Correct_Repetition("Correct Repetition", Float) = 0
+          //endex
+
           //ifex _Ray_Marching_Baked_Origins_Enabled==0
           [HideInInspector] m_start_Ray_Marching_Baked_Origins("Baked Origins", Float) = 0
             [ThryToggle(_RAY_MARCHING_BAKED_ORIGINS)] _Ray_Marching_Baked_Origins_Enabled("Enable", Float) = 0
diff --git a/features.cginc b/features.cginc
index d74ef01..3a1a773 100644
--- a/features.cginc
+++ b/features.cginc
@@ -80,6 +80,10 @@
 #pragma shader_feature_local _RAY_MARCHING_OVERSTEP
 //endex
 
+//ifex _Ray_Marching_Correct_Repetition_Enabled==0
+#pragma shader_feature_local _RAY_MARCHING_CORRECT_REPETITION
+//endex
+
 //ifex _Ray_Marching_Baked_Origins_Enabled==0
 #pragma shader_feature_local _RAY_MARCHING_BAKED_ORIGINS
 //endex
diff --git a/ray_marching.cginc b/ray_marching.cginc
index 6184881..39da35c 100644
--- a/ray_marching.cginc
+++ b/ray_marching.cginc
@@ -23,6 +23,75 @@ void GetRoRd(v2f i, out float3 ro, out float3 rd) {
   rd = mul((float3x3)unity_WorldToObject, rd_world);
 }
 
+float map(float3 p) {
+    float d = 1e9;
+#if defined(_RAY_MARCHING_BALL)
+    {
+      float r = _Ray_Marching_Ball_Radius;
+      d = min(d, map_ball(p, _Ray_Marching_Ball_Radius));
+    }
+#endif
+#if defined(_RAY_MARCHING_HEXAGON)
+    {
+      float r = _Ray_Marching_Hexagon_Radius;
+      float h = _Ray_Marching_Hexagon_Height;
+      d = min(d, map_hexagon(p, float2(r, h)));
+    }
+#endif
+  return d;
+}
+
+float domain_repeat(inout float3 p) {
+  float d;
+#if defined(_RAY_MARCHING_CART_GRID)
+  {
+    float3 count = float3(_Ray_Marching_Cart_Grid_Count_X, _Ray_Marching_Cart_Grid_Count_Y, _Ray_Marching_Cart_Grid_Count_Z);
+    float3 period = 1.0f / count;
+    period *= 2;
+    float3 half_period = period*0.5f;
+    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;
+    }
+    d = map(p);
+  }
+#elif defined(_RAY_MARCHING_HEX_GRID)
+  {
+    const float3 count = _Ray_Marching_Hex_Grid_Count * 0.5f;
+    const float3 period = 1.0f / count;
+    const float3 hex = cart_to_hex(p.xy);
+
+    float half_period = period * 0.5;
+    float3 which = floor((hex + half_period) / period);
+
+    // The original code here was this:
+    //   p_hex = glsl_mod(p_hex + half_period, period) - half_period;
+    //
+    // But you can simplify it. Given the definition of glsl_mod:
+    //   #define glsl_mod(x,y) (((x)-(y)*floor((x)/(y))))
+    //
+    // You can plug in terms:
+    //  (p_hex + half_period) - (period) * floor((p_hex + half_period) / period)
+    //  = p_hex + half_period - period * floor(p_hex/period + 0.5)
+    //
+    // For all x,
+    //  round(x) = floor(x + 0.5)
+    //
+    // Continuing to simplify:
+    //  (p_hex + half_period - period * round(p_hex/period)) - half_period
+    //  = p_hex - period * round(p_hex / period)
+    const float3 hex_inst = hex - period * round_hex(hex / period);
+
+    p.xy = (any(abs(which) > count/2) ? 1e9 : hex_to_cart(hex_inst));
+
+    d = map(p);
+  }
+#endif
+  return d;
+}
+
 void ray_march(inout v2f i) {
 #if defined(_RAY_MARCHING)
   float3 ro, rd;
@@ -44,68 +113,8 @@ void ray_march(inout v2f i) {
   float3 hit_pos;
   for (uint ii = 0; ii < kMaxIter; ++ii) {
     float3 p = ro + rd * d_acc;
-    d_cur = 1e9;
-
-    // Coordinate system transformations.
-#if defined(_RAY_MARCHING_CART_GRID)
-    {
-      float3 count = float3(_Ray_Marching_Cart_Grid_Count_X, _Ray_Marching_Cart_Grid_Count_Y, _Ray_Marching_Cart_Grid_Count_Z);
-      float3 period = 1.0f / count;
-      period *= 2;
-      float3 half_period = period*0.5f;
-      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;
-      }
-    }
-#endif
-#if defined(_RAY_MARCHING_HEX_GRID)
-    {
-      const float3 count = _Ray_Marching_Hex_Grid_Count * 0.5f;
-      const float3 period = 1.0f / count;
-      const float3 hex = cart_to_hex(p.xy);
-
-      float half_period = period * 0.5;
-      float3 which = floor((hex + half_period) / period);
-
-      // The original code here was this:
-      //   p_hex = glsl_mod(p_hex + half_period, period) - half_period;
-      //
-      // But you can simplify it. Given the definition of glsl_mod:
-      //   #define glsl_mod(x,y) (((x)-(y)*floor((x)/(y))))
-      //
-      // You can plug in terms:
-      //  (p_hex + half_period) - (period) * floor((p_hex + half_period) / period)
-      //  = p_hex + half_period - period * floor(p_hex/period + 0.5)
-      //
-      // For all x,
-      //  round(x) = floor(x + 0.5)
-      //
-      // Continuing to simplify:
-      //  (p_hex + half_period - period * round(p_hex/period)) - half_period
-      //  = p_hex - period * round(p_hex / period)
-      const float3 hex_inst = hex - period * round_hex(hex / period);
-
-      p.xy = (any(abs(which) > count/2) ? 1e9 : hex_to_cart(hex_inst));
-    }
-#endif
 
-    // Sdfs.
-#if defined(_RAY_MARCHING_BALL)
-    {
-      float r = _Ray_Marching_Ball_Radius;
-      d_cur = min(d_cur, map_ball(p, _Ray_Marching_Ball_Radius));
-    }
-#endif
-#if defined(_RAY_MARCHING_HEXAGON)
-    {
-      float r = _Ray_Marching_Hexagon_Radius;
-      float h = _Ray_Marching_Hexagon_Height;
-      d_cur = min(d_cur, map_hexagon(p, float2(r, h)));
-    }
-#endif
+    d_cur = domain_repeat(p);
 
 #if defined(_RAY_MARCHING_OVERSTEP)
     d_cur *= (d_cur > 0 ? _Ray_Marching_Overstepping_Factor : 1.0f);