libgarbage: change default to be only using one sdf function, with materials, since it seems to get optimised out anyway

Assets/raymarched/Raymarching.unity

@@ -598,8 +598,8 @@ Transform:
   m_PrefabAsset: {fileID: 0}
   m_GameObject: {fileID: 683266143}
   m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
-  m_LocalPosition: {x: 0, y: 0.26, z: -0.407}
+  m_LocalPosition: {x: 0, y: 0, z: 0}
-  m_LocalScale: {x: 10, y: 10, z: 10}
+  m_LocalScale: {x: 1, y: 1, z: 1}
   m_Children: []
   m_Father: {fileID: 0}
   m_RootOrder: 7
@@ -1678,7 +1678,7 @@ Transform:
   m_PrefabAsset: {fileID: 0}
   m_GameObject: {fileID: 1485771011}
   m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
-  m_LocalPosition: {x: 0.429, y: 0.221, z: -1.243}
+  m_LocalPosition: {x: 0.429, y: 0.221, z: -1.743}
   m_LocalScale: {x: 19.2, y: 1, z: 1}
   m_Children: []
   m_Father: {fileID: 0}
@@ -1761,7 +1761,7 @@ Transform:
   m_PrefabAsset: {fileID: 0}
   m_GameObject: {fileID: 1500710831}
   m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
-  m_LocalPosition: {x: 0, y: 1, z: -10}
+  m_LocalPosition: {x: 0, y: 0.009, z: -0.786}
   m_LocalScale: {x: 1, y: 1, z: 1}
   m_Children: []
   m_Father: {fileID: 0}

Assets/raymarched/lib/libgarbage.cginc

@@ -3,23 +3,39 @@
 #include "UnityCG.cginc"
 
 /*
-# defines with no defaults
+## defines with no defaults
-USE_WORLD_SPACE
+
-DISCARD_ON_MISS
+# default is object space
-USE_MATERIALS_IN_RAYMARCH // TODO: implement, this is easier to work with but more expensive
+	USE_WORLD_SPACE
-DISABLE_DEPTH
+
+# renders missed rays as transparent
+	DISCARD_ON_MISS
+
+# use if the shape of the scene is significnatly different from the shape of the material space
+# will use SCENE_FN only for the final step, and DISTANCE_FN for raymarching
+# DISTANCE_FN must return a float
+	SEPARATE_MATERIAL_AND_DIST_FUNCTIONS
+
+# don't write depth (will have the depth defined by the original mesh)
+	DISABLE_DEPTH
+
 START_RAYS_IN_BOX // TODO: implement
 START_RAYS_IN_SPHERE // TODO: implement
 */
 
-// scene sdf with only distance
-#ifndef DISTANCE_FN
-#define DISTANCE_FN default_distance_sdf
-#endif
 
 // scene sdf that includes material data
-#ifndef MATERIAL_FN
+#ifndef SCENE_FN
-#define MATERIAL_FN default_material_sdf
+#define SCENE_FN default_material_sdf
+#endif
+
+#ifdef SEPARATE_MATERIAL_AND_DIST_FUNCTIONS
+	// scene sdf with only distance
+	#ifndef DISTANCE_FN
+	#define DISTANCE_FN default_distance_sdf
+	#endif
+#else
+	#define DISTANCE_FN material_fn_as_dist
 #endif
 
 // calculates a color from a Ray
@@ -105,7 +121,7 @@ struct Ray {
 
 
 float DISTANCE_FN(float3 p);
-SurfacePoint MATERIAL_FN(float3 p);
+SurfacePoint SCENE_FN(float3 p);
 float3 LIGHT_FN(Ray ray);
 Ray cast_ray(float3 p, float3 d, float startDist = 0);
 
@@ -219,7 +235,7 @@ Ray cast_ray(float3 start, float3 dir, float start_len) {
 		ray.mat = mat();
 	} else {
 		ray.normal = get_normal(ray.hit_pos, ray.dist);
-		ray.mat = MATERIAL_FN(ray.hit_pos).mat;
+		ray.mat = SCENE_FN(ray.hit_pos).mat;
 	}
 	return ray;
 }
@@ -228,6 +244,10 @@ float default_distance_sdf(float3 p) {
 	return sdSphere(p, 0.5);
 }
 
+float material_fn_as_dist(float3 p) {
+	return SCENE_FN(p).dist;
+}
+
 SurfacePoint default_material_sdf(float3 p) {
 	return mSphere(p, 0.5);
 }

Assets/raymarched/lib/libgarbage_example.shader

@@ -5,7 +5,7 @@ Shader "CrispyPin/LibGarbageExample"
 		[Header(Raymarcher Properties)]
 		_MaxSteps ("Max steps", Int) = 128
 		_MaxDist ("Max distance", Float) = 128
-		_SurfDist ("Surface distance threshold", Range(0.00001, 0.05)) = 0.001
+		_SurfDist ("Surface distance threshold", Range(0.0001, 0.05)) = 0.001
 
 	}
 	SubShader
@@ -21,38 +21,28 @@ Shader "CrispyPin/LibGarbageExample"
 			#pragma fragment frag
 
 			int _MaxSteps;
-			#define MAX_STEPS _MaxSteps
 			float _MaxDist;
-			#define MAX_DIST _MaxDist
 			float _SurfDist;
+			#define MAX_STEPS _MaxSteps
+			#define MAX_DIST _MaxDist
 			#define SURF_DIST _SurfDist
 
 			#define REFLECTIONS 3
-			#define DISTANCE_FN main_dist
+
-			#define MATERIAL_FN main_mat
 			#define LIGHT_FN lighting
+			#define SCENE_FN main
+
+			// #define SEPARATE_MATERIAL_AND_DIST_FUNCTIONS
+			// #define SCENE_FN separate_mat
+			// #define DISTANCE_FN separate_dist
+
 			// #define DISABLE_DEPTH
 			// #define DISCARD_ON_MISS
-			#define USE_WORLD_SPACE
+			// #define USE_WORLD_SPACE
 			#define SCENE_SCALE 0.05
-
 			#include "libgarbage.cginc"
 
-			float main_dist(float3 p) {
+			SurfacePoint main(float3 p) {
-				float d = sdPlaneY(p, 0);
-				d = qIntersect(d, sdSphere(p, 9), 0.5);
-				d = qUnion(d, sdSphere(p - float3(0, 2, 0), 2));
-				d = qUnion(d, sdTorus(rotX(p, _Time * 40 + UNITY_PI / 2), 5, 0.5), 0.5);
-				d = qUnion(d, sdTorus(rotZ(p, _Time * 40 + UNITY_PI / 2), 5, 0.5), 0.5);
-				d = qUnion(d, sdTorus(rotX(p, _Time * 40), 5, 0.5), 0.5);
-				d = qUnion(d, sdTorus(rotZ(p, _Time * 40), 5, 0.5), 0.5);
-				// small spheres
-				float3 p2 = abs(rotY(p, -20 * _Time)) - float3(1.5, sin(_Time.y * 5) + 1, 1.5);
-				d = qUnion(d, sdSphere(p2, 0.7), 0.2);
-				return d;
-			}
-
-			SurfacePoint main_mat(float3 p) {
 				Material grass = mat(float3(0.001, 0.1, 0.001), 0.3);
 				Material dirt = mat(float3(0.1, 0.04, 0.01), 0);
 				Material metal = mat(0.1, 1);
@@ -71,10 +61,19 @@ Shader "CrispyPin/LibGarbageExample"
 				return d;
 			}
 
+			SurfacePoint separate_mat(float3 p) {
+				Material blue = mat(float3(0.05, 0.1, 0.2), 0);
+				SurfacePoint d = mSphere(p, 1, blue);
+				return d;
+			}
+
+			float separate_dist(float3 p) {
+				return main(p).dist;
+			}
+
 			float3 lighting(Ray ray) {
 				if (ray.missed)
 					return lRenderSky(ray.dir, normalize(float3(4,2,1)));
-					// return float3(0.15, 0.25, 0.3);
 
 				float3 sun_dir = normalize(float3(4, 2, 1));
 				float3 col = 0;