add hypotrochoid gimmick

1 files changed, 25 insertions, 0 deletions

diff --git a/2ner.cginc b/2ner.cginc
index 1e6af31..0e6fa82 100644
--- a/2ner.cginc
+++ b/2ner.cginc
@@ -25,6 +25,7 @@
 #include "ssao.cginc"

 #include "ssfd.cginc"

 #include "tessellation.cginc"

+#include "trochoid.cginc"

 #include "unigram_letter_grid.cginc"

 #include "vertex_domain_warping.cginc"

 #include "yum_brdf.cginc"

@@ -117,6 +118,11 @@ v2f vert(appdata v) {
   v.vertex.xyz = domainWarpVertexPosition(v.vertex.xyz);

 #endif

 

+#if defined(_TROCHOID)

+  o.orig_pos = v.vertex.xyz;

+  v.vertex.xyz = trochoid_map(v.vertex.xyz);

+#endif

+

 #if defined(OUTLINE_PASS)

   [branch]

   if (!_Outlines_Enabled_Dynamic) {

@@ -299,6 +305,7 @@ float4 frag(v2f i, uint facing : SV_IsFrontFace
 

 #if defined(_SHATTER_WAVE)

   calcNormalInScreenSpace(i.normal, i.objPos);

+  i.normal = UnityObjectToWorldNormal(i.normal);

 #endif

 

 #if defined(_SHATTER_WAVE) || defined(_VERTEX_DOMAIN_WARPING) || defined(_TESSELLATION_HEIGHTMAP)

@@ -399,6 +406,24 @@ float4 frag(v2f i, uint facing : SV_IsFrontFace
 #endif

 #endif

 

+#if defined(_TROCHOID)

+  float3 normal_obj = trochoid_normal(i.orig_pos);

+

+  // We need tangents that are perpendicular to the new normal.

+  // A common way to generate them is to cross with a fixed "up" vector.

+  float3 tangent_obj = normalize(cross(normal_obj, float3(0, 1, 0)));

+  float3 binormal_obj = cross(normal_obj, tangent_obj);

+

+  i.normal = UnityObjectToWorldNormal(normal_obj);

+  i.tangent = float4(normalize(mul((float3x3)unity_ObjectToWorld, tangent_obj)), 1);

+  i.binormal = normalize(mul((float3x3)unity_ObjectToWorld, binormal_obj));

+  i.normal *= facing ? 1 : -1;

+

+  float theta = 1 - atan2(i.orig_pos.y, i.orig_pos.x) / PI;

+  float3 color = _Trochoid_Color_Ramp.SampleLevel(linear_clamp_s, float2(theta, 0.5), 0).rgb;

+  pbr.albedo.xyz = color;

+#endif

+

 #if defined(_HARNACK_TRACING)

   HarnackTracingOutput harnack_output = HarnackTracing(i);

   pbr.albedo = float4(1, 1, 1, 0.2);