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#ifndef __CUSTOM30_INC
#define __CUSTOM30_INC
#include "globals.cginc"
#include "quilez.cginc"
#include "interpolators.cginc"
#if defined(_CUSTOM30)
#define CUSTOM30_MAX_STEPS 30
struct Custom30Output {
float3 objPos;
float3 normal;
float depth;
};
float3 GetFragToOrigin(v2f i) {
// Vector from fragment to origin
return float3(-1, 1, 1) * (i.color * 2.0f - 1.0f) / i.color.a;
}
float cut_with_box(float3 p, float d, float3 box_size) {
float2 pp_xy = p.xy;
float2 pp_xz = p.xz;
float2 pp_yz = p.yz;
// Rotate by 45 degrees
float c = 0.70710678;
float s = 0.70710678;
pp_xy = float2(c * p.x - s * p.y, s * p.x + c * p.y);
d = max(d, distance_from_box(float3(pp_xy, p.z), box_size));
pp_xz = float2(c * p.x - s * p.z, s * p.x + c * p.z);
d = max(d, distance_from_box(float3(pp_xz, p.y), box_size));
pp_yz = float2(c * p.y - s * p.z, s * p.y + c * p.z);
d = max(d, distance_from_box(float3(pp_yz, p.x), box_size));
return d;
}
#if defined(_CUSTOM30_BASICCUBE)
float BasicCube_map(float3 p) {
float box_d = distance_from_box_frame(p, .995, .15);
float core_d = distance_from_box(p, 0.95);
float d = min(box_d, core_d);
d = cut_with_box(p, d, 1.3);
return d;
}
float3 BasicCube_normal(float3 p) {
float epsilon = 1E-3;
float center_d = BasicCube_map(p);
float3 n = float3(
BasicCube_map(p + float3(epsilon, 0, 0)) - center_d,
BasicCube_map(p + float3(0, epsilon, 0)) - center_d,
BasicCube_map(p + float3(0, 0, epsilon)) - center_d);
return normalize(n);
}
Custom30Output BasicCube(v2f i) {
float3 objSpaceCameraPos = mul(unity_WorldToObject, float4(_WorldSpaceCameraPos, 1.0));
float3 frag_to_origin = GetFragToOrigin(i);
float3 ro = -frag_to_origin;
float3 rd = normalize(i.objPos - objSpaceCameraPos);
float d;
float d_acc = 0;
float epsilon = 5E-3;
// 1.73... = sqrt(3)
// our cube has an edge length of 2, so mult by 2
float max_d = 1.73205081f * 2.0f;
[loop]
for (uint ii = 0; ii < CUSTOM30_MAX_STEPS; ++ii) {
float3 p = ro + rd * d_acc;
d = BasicCube_map(p);
d_acc += d;
if (d < epsilon) break;
if (d_acc > max_d) break;
}
Custom30Output o;
clip(epsilon - d);
float3 objPos = ro + rd * d_acc;
o.objPos = objPos;
// Transform from SDF space back to object space
float3 objSpacePos = objPos + (i.objPos + frag_to_origin);
float4 clipPos = UnityObjectToClipPos(objSpacePos);
o.depth = clipPos.z / clipPos.w;
o.normal = BasicCube_normal(objPos);
return o;
}
#endif
#if defined(_CUSTOM30_BASICWEDGE)
float BasicWedge_map(float3 p) {
float box_d = distance_from_box(p, float3(1, 1, 1));
float cut_plane_d = distance_from_plane(p - float3(0, 0, 0), -normalize(float3(1, 0, 1)), 0);
float d = op_sub(box_d, cut_plane_d);
//d = cut_with_box(p, d, 1.3);
return d;
}
float3 BasicWedge_normal(float3 p) {
float epsilon = 1E-3;
float center_d = BasicWedge_map(p);
float3 n = float3(
BasicWedge_map(p + float3(epsilon, 0, 0)) - center_d,
BasicWedge_map(p + float3(0, epsilon, 0)) - center_d,
BasicWedge_map(p + float3(0, 0, epsilon)) - center_d);
return normalize(n);
}
Custom30Output BasicWedge(v2f i) {
float3 objSpaceCameraPos = mul(unity_WorldToObject, float4(_WorldSpaceCameraPos, 1.0));
float3 frag_to_origin = GetFragToOrigin(i);
float3 ro = -frag_to_origin;
float3 rd = normalize(i.objPos - objSpaceCameraPos);
float d;
float d_acc = 0;
float epsilon = 5E-3;
// 1.73... = sqrt(3)
// our cube has an edge length of 2, so mult by 2
float max_d = 1.73205081f * 2.0f;
[loop]
for (uint ii = 0; ii < CUSTOM30_MAX_STEPS; ++ii) {
float3 p = ro + rd * d_acc;
d = BasicWedge_map(p);
d_acc += d;
if (d < epsilon) break;
if (d_acc > max_d) break;
}
Custom30Output o;
clip(epsilon - d);
float3 objPos = ro + rd * d_acc;
o.objPos = objPos;
// Transform from SDF space back to object space
float3 objSpacePos = objPos + (i.objPos + frag_to_origin);
float4 clipPos = UnityObjectToClipPos(objSpacePos);
o.depth = clipPos.z / clipPos.w;
o.normal = BasicWedge_normal(objPos);
return o;
}
#endif
#endif // _CUSTOM30
#endif // __CUSTOM30_INC
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