A signed distance function generator running inside Unity. An example result raymarched scene can be found here or here.
It lets the user make and combine distance functions to make interesting scenes, inside an intuitive editor such as Unity. It tries to optimize the code for specific known cases (for example, it tries to prevent using matrices when dealing with planes), but it is far from complete.
It also features a generic, dynamic raymarching renderer inside Unity's editor so that composing the final SDF is easy. However, because it is generic it is also very slow (unless using the optimized output code), so it uses an iterative approach to converge to the solution.
It can output GLSL and HLSL code.
As an example, it converts the following scene:
Into the following code:
const mat4 tr[45] = mat4[45](
mat4(.999, .0, .055, .0, .0, 1.0, .0, .0, -.055, .0, .999, .0, -1.509, .14, .498, 1.0),
mat4(.795, .934, 2.28, .0, -.491, 1.642, -1.25, .0, -1.401, -.045, 1.732, .0, -.397, -.911, -7.876, 1.0),
mat4(.5, .0, .0, .0, .0, .137, -.104, .0, .0, .029, .489, .0, -.8, -.064, .867, 1.0),
mat4(1.128, .386, .417, .0, -.926, .053, 1.543, .0, 1.235, -.313, .775, .0, -.769, -1.532, -2.843, 1.0),
mat4(-1.008, .237, -1.253, .0, -1.259, .149, 1.228, .0, 1.027, .415, .275, .0, 4.273, -.714, -.96, 1.0),
mat4(-1.633, -.219, .498, .0, .244, .173, 1.651, .0, -.964, .415, -.425, .0, 3.007, -.072, -3.193, 1.0),
mat4(-.526, -.46, -.495, .0, -1.791, .161, -.242, .0, .411, .112, -1.689, .0, 5.514, .189, 1.112, 1.0),
mat4(.788, .097, .425, .0, -.135, .792, .022, .0, -.418, -.073, .795, .0, 1.929, -6.665, -.972, 1.0),
mat4(.203, .084, .048, .0, -.057, .293, -.032, .0, -.028, .013, .407, .0, -.895, .281, 1.418, 1.0),
mat4(.149, .025, -.291, .0, .07, .222, .18, .0, .135, -.143, .228, .0, -.128, .448, .615, 1.0),
mat4(.163, -.007, .238, .0, -.015, .102, .035, .0, -.23, -.012, .166, .0, -.815, .176, -.268, 1.0),
mat4(1.68, -.01, .848, .0, -.871, .133, 1.509, .0, -.276, -.482, .4, .0, -5.624, -1.2, .976, 1.0),
mat4(-1.288, -.085, -1.277, .0, -1.377, .184, 1.044, .0, .314, .457, -.658, .0, 2.367, .783, 2.615, 1.0),
mat4(-.526, -.46, -.495, .0, -1.791, .161, -.242, .0, .411, .112, -1.689, .0, 1.346, .968, -.74, 1.0),
mat4(.649, .468, -.157, .0, -1.578, .171, .798, .0, .862, -.04, 1.579, .0, .804, -1.56, 3.123, 1.0),
mat4(-.446, -.32, 1.219, .0, -1.751, .078, -.321, .0, .016, -.369, -1.124, .0, -1.128, -.361, -6.142, 1.0),
mat4(1.533, .154, .696, .0, -.87, .377, .718, .0, -.329, -.281, 1.342, .0, -4.104, -1.442, -.118, 1.0),
mat4(1.853, -.102, -.211, .0, .221, -.014, 1.757, .0, -.392, -.489, -.008, .0, -1.772, -1.406, 6.376, 1.0),
mat4(-.556, -.453, -.525, .0, -.17, -.141, 1.687, .0, -1.815, .152, .003, .0, -1.992, -.067, 6.05, 1.0),
mat4(-.943, -.128, .043, .0, -.107, 1.049, .137, .0, -.059, .146, -.94, .0, 1.858, .33, -1.42, 1.0),
mat4(.7, .065, .111, .0, -.117, .263, -.261, .0, -.161, .092, .671, .0, -1.761, -.553, -.067, 1.0),
mat4(1.676, .466, 1.232, .0, -1.862, .058, 1.912, .0, 1.213, -.556, 1.231, .0, -3.822, -1.844, -6.583, 1.0),
mat4(-1.467, .491, -1.337, .0, -1.788, .06, 1.971, .0, 1.549, .534, 1.009, .0, 6.023, -1.973, -.383, 1.0),
mat4(-2.494, -.141, 1.034, .0, .951, .2, 2.324, .0, -.79, .686, -.467, .0, 6.624, -.322, -6.471, 1.0),
mat4(-1.116, -.568, -1.242, .0, -2.513, .31, .163, .0, .432, .334, -2.263, .0, 7.905, .708, 4.921, 1.0),
mat4(-.025, -.278, 1.937, .0, -.454, 1.573, .319, .0, -1.912, -.37, -.101, .0, .038, -4.893, -1.369, 1.0),
mat4(.326, .111, .293, .0, -.106, .197, -.236, .0, -.365, .042, .33, .0, -1.141, -.145, -1.004, 1.0),
mat4(1.01, .023, 1.506, .0, -1.623, .004, .939, .0, .032, -.499, .078, .0, -4.952, -.781, -2.879, 1.0),
mat4(-1.354, .304, -.64, .0, -.774, .034, 1.62, .0, 1.106, .396, .35, .0, 2.953, -1.14, 2.649, 1.0),
mat4(-1.462, -.104, 1.084, .0, .892, .238, 1.325, .0, -.851, .427, -.474, .0, 6.541, .212, -.951, 1.0),
mat4(-1.166, -.349, -.663, .0, -1.442, .328, .007, .0, .463, .142, -1.648, .0, 3.098, 1.04, 2.74, 1.0),
mat4(.024, .494, .28, .0, -1.723, -.028, .764, .0, .829, -.074, 1.579, .0, .498, -2.115, -.172, 1.0),
mat4(.795, .0, -.714, .0, .302, 3.241, .336, .0, .647, -1.512, .721, .0, -.378, -3.143, .939, 1.0),
mat4(.28, .504, 2.966, .0, -.047, 1.821, -.83, .0, -1.66, .033, .523, .0, 1.505, 4.294, -7.819, 1.0),
mat4(.5, .0, .0, .0, .0, .137, -.104, .0, .0, .029, .489, .0, -.805, -.247, .582, 1.0),
mat4(1.128, .386, .417, .0, -.926, .053, 1.543, .0, 1.235, -.313, .775, .0, -.769, -1.532, -2.843, 1.0),
mat4(-1.008, .237, -1.253, .0, -1.259, .149, 1.228, .0, 1.027, .415, .275, .0, 4.273, -.714, -.96, 1.0),
mat4(-1.633, -.219, .498, .0, .244, .173, 1.651, .0, -.964, .415, -.425, .0, 3.007, -.072, -3.193, 1.0),
mat4(-.526, -.46, -.495, .0, -1.791, .161, -.242, .0, .411, .112, -1.689, .0, 5.514, .189, 1.112, 1.0),
mat4(1.43, -.088, -1.481, .0, -.092, 1.769, -.567, .0, .828, .35, 2.494, .0, -1.382, -4.146, -2.058, 1.0),
mat4(.461, .046, -.065, .0, -.193, .102, -.182, .0, -.02, .084, .259, .0, -.378, -.212, .663, 1.0),
mat4(1.128, .386, .417, .0, -.926, .053, 1.543, .0, 1.235, -.313, .775, .0, -.769, -1.532, -2.843, 1.0),
mat4(-1.008, .237, -1.253, .0, -1.259, .149, 1.228, .0, 1.027, .415, .275, .0, 4.057, -.994, -1.057, 1.0),
mat4(-1.633, -.219, .498, .0, .244, .173, 1.651, .0, -.964, .415, -.425, .0, 3.007, -.072, -3.193, 1.0),
mat4(-.526, -.46, -.495, .0, -1.791, .161, -.242, .0, .411, .112, -1.689, .0, 5.374, .102, 1.328, 1.0)
);
float sdf_generated(vec3 p)
{
vec3 wsPos = vec3(.0,.0,.0);
float stack[12];
vec4 pStack[12];
pStack[0] = vec4(p, 1.0);
pStack[0] = (pStack[0] * vec4(1.0,.98,1.0,1.0));
pStack[1] = pStack[0];
pStack[2] = (tr[0] * pStack[1]);
pStack[2].xz = pModPolar(pStack[2].xz , 8.0);
pStack[3] = (tr[1] * pStack[2]);
wsPos = (tr[2] * pStack[3]).xyz;
stack[3] = fBox(wsPos);
wsPos = (tr[3] * pStack[3]).xyz;
stack[3] = max(stack[3],frPlane(wsPos));
wsPos = (tr[4] * pStack[3]).xyz;
stack[3] = max(stack[3],frPlane(wsPos));
wsPos = (tr[5] * pStack[3]).xyz;
stack[3] = max(stack[3],frPlane(wsPos));
wsPos = (tr[6] * pStack[3]).xyz;
stack[3] = max(stack[3],frPlane(wsPos));
stack[2] = stack[3];
pStack[4] = (tr[7] * pStack[1]);
pStack[5] = pStack[4];
pStack[6] = pStack[5];
wsPos = (tr[8] * pStack[6]).xyz;
stack[6] = fBox(wsPos);
wsPos = (tr[9] * pStack[6]).xyz;
stack[6] = min(stack[6],fBox(wsPos));
wsPos = (tr[10] * pStack[5]).xyz;
stack[5] = max(-stack[6],fBox(wsPos));
wsPos = (tr[11] * pStack[4]).xyz;
stack[4] = max(stack[5],frPlane(wsPos));
wsPos = (tr[12] * pStack[4]).xyz;
stack[4] = max(stack[4],frPlane(wsPos));
wsPos = (tr[13] * pStack[4]).xyz;
stack[4] = max(stack[4],frPlane(wsPos));
wsPos = (tr[14] * pStack[4]).xyz;
stack[4] = max(stack[4],frPlane(wsPos));
wsPos = (tr[15] * pStack[4]).xyz;
stack[4] = max(stack[4],frPlane(wsPos));
wsPos = (tr[16] * pStack[4]).xyz;
stack[4] = max(stack[4],frPlane(wsPos));
wsPos = (tr[17] * pStack[4]).xyz;
stack[4] = max(stack[4],frPlane(wsPos));
wsPos = (tr[18] * pStack[4]).xyz;
stack[4] = max(stack[4],frPlane(wsPos));
stack[1] = min(stack[2],stack[4]);
pStack[7] = (tr[19] * pStack[1]);
pStack[7].xz = pModPolar(pStack[7].xz , 10.0);
wsPos = (tr[20] * pStack[7]).xyz;
stack[7] = fBox(wsPos);
wsPos = (tr[21] * pStack[7]).xyz;
stack[7] = max(stack[7],frPlane(wsPos));
wsPos = (tr[22] * pStack[7]).xyz;
stack[7] = max(stack[7],frPlane(wsPos));
wsPos = (tr[23] * pStack[7]).xyz;
stack[7] = max(stack[7],frPlane(wsPos));
wsPos = (tr[24] * pStack[7]).xyz;
stack[7] = max(stack[7],frPlane(wsPos));
stack[1] = min(stack[1],stack[7]);
pStack[8] = (tr[25] * pStack[1]);
pStack[8].xz = pModPolar(pStack[8].xz , 5.0);
wsPos = (tr[26] * pStack[8]).xyz;
stack[8] = fBox(wsPos);
wsPos = (tr[27] * pStack[8]).xyz;
stack[8] = max(stack[8],frPlane(wsPos));
wsPos = (tr[28] * pStack[8]).xyz;
stack[8] = max(stack[8],frPlane(wsPos));
wsPos = (tr[29] * pStack[8]).xyz;
stack[8] = max(stack[8],frPlane(wsPos));
wsPos = (tr[30] * pStack[8]).xyz;
stack[8] = max(stack[8],frPlane(wsPos));
wsPos = (tr[31] * pStack[8]).xyz;
stack[8] = max(stack[8],frPlane(wsPos));
stack[1] = min(stack[1],stack[8]);
pStack[9] = (tr[32] * pStack[1]);
pStack[9].xz = pModPolar(pStack[9].xz , 6.0);
pStack[10] = (tr[33] * pStack[9]);
wsPos = (tr[34] * pStack[10]).xyz;
stack[10] = fBox(wsPos);
wsPos = (tr[35] * pStack[10]).xyz;
stack[10] = max(stack[10],frPlane(wsPos));
wsPos = (tr[36] * pStack[10]).xyz;
stack[10] = max(stack[10],frPlane(wsPos));
wsPos = (tr[37] * pStack[10]).xyz;
stack[10] = max(stack[10],frPlane(wsPos));
wsPos = (tr[38] * pStack[10]).xyz;
stack[10] = max(stack[10],frPlane(wsPos));
stack[9] = stack[10];
stack[1] = min(stack[1],stack[9]);
pStack[11] = (tr[39] * pStack[1]);
wsPos = (tr[40] * pStack[11]).xyz;
stack[11] = fBox(wsPos);
wsPos = (tr[41] * pStack[11]).xyz;
stack[11] = max(stack[11],frPlane(wsPos));
wsPos = (tr[42] * pStack[11]).xyz;
stack[11] = max(stack[11],frPlane(wsPos));
wsPos = (tr[43] * pStack[11]).xyz;
stack[11] = max(stack[11],frPlane(wsPos));
wsPos = (tr[44] * pStack[11]).xyz;
stack[11] = max(stack[11],frPlane(wsPos));
stack[1] = min(stack[1],stack[11]);
stack[0] = max(stack[1],dot(pStack[0].xyz - vec3(1.24,.07,2.43), vec3(-.129,-.864,.486)));
stack[0] = max(stack[0],dot(pStack[0].xyz - vec3(-.2,-1.41,1.48), vec3(.107,-.943,-.314)));
return stack[0];
}
Another example scene:
float sdf(vec3 p)
{
vec3 wsPos = vec3(.0,.0,.0);
vec4 a0 = vec4(p, 1.0);
a0.xz = abs(a0.xz) * vec2(-1.0,1.0);
vec4 a1 = a0 - vec4(6.24,.0,2.5,.0);
a1.xz = pModPolar(a1.xz , 4.0);
float d1 = dot(a1.xyz - vec3(11.49,.0,.0), vec3(-1.0,.0,.0));
vec4 a2 = a1 - vec4(11.02,2.15,7.28,.0);
a2.z = domainRepeat1D(a2.z , 2.0);
vec4 a3 = a2;
wsPos = a3.xyz - vec3(-2.64,5.05,.0);
float d3 = fBox(wsPos,vec3(.5,.5,.228));
wsPos = a3.xyz - vec3(-2.275,5.05,.0);
d3 = min(d3,fBox(wsPos,vec3(.383,.383,.175)));
wsPos = a3.xyz - vec3(-2.64,6.97,.0);
d3 = min(d3,fBox(wsPos,vec3(.5,.283,.111)));
wsPos = a2.xyz - vec3(-1.28,6.38,.287);
float d2 = max(-d3,fBox(wsPos,vec3(1.5,1.893,6.673)));
d1 = min(d1,d2);
vec4 a4 = a1 - vec4(9.18,-4.5,-.032,.0);
a4.y = domainRepeat1D(a4.y , 4.5);
vec4 a5 = a4;
a5.z = domainRepeat1D(a5.z , 2.5);
vec4 a6 = a5;
a6.x = -a6.x;
vec4 a7 = a6;
vec4 a8 = a7 - vec4(.05,-.62,.0,.0);
a8.xyz = rdZ(a8.xyz);
wsPos = a8.xyz;
float d8 = (fCylinder(wsPos, 1.398,1.361)*.75);
wsPos = a8.xyz - vec3(.0,.152,.0);
d8 = max(-d8,(fCylinder(wsPos, 1.434,.531)*.75));
wsPos = a7.xyz - vec3(.786,.46,.0);
float d7 = max(d8,fBox(wsPos,vec3(.523,.747,1.415)));
vec4 a9 = a6;
wsPos = a9.xyz - vec3(.47,1.953,.0);
float d9 = fBox(wsPos,vec3(.5,.075,1.5));
wsPos = a9.xyz - vec3(.58,2.03,.0);
d9 = min(d9,fBox(wsPos,vec3(.5,.075,1.5)));
vec4 a10 = a9 - vec4(.463,-.51,1.179,.0);
a10.z = domainRepeat1D(a10.z , 2.35);
wsPos = a10.xyz;
float d10 = fBox(wsPos,vec3(.24,.033,.24));
wsPos = a10.xyz - vec3(.0,-.093,.0);
d10 = min(d10,fBox(wsPos,vec3(.24,.033,.24)));
wsPos = a10.xyz - vec3(-2.8,-.03,.0);
d10 = min(d10,fBox(wsPos,vec3(.25,.075,.25)));
vec4 a11 = a10;
a11.xz = pModPolar(a11.xz , 8.0);
wsPos = a11.xyz - vec3(.002,-1.07,.0);
float d11 = fBox(wsPos,vec3(.17,1.053,.424));
d10 = min(d10,d11);
d9 = min(d9,d10);
vec4 a12 = a9 - vec4(-1.03,-.518,.0,.0);
vec4 a13 = a12;
a13.xyz = rdZ(a13.xyz);
wsPos = (tr[0] * a13).xyz;
float d13 = fCylinder(wsPos, 1.225,3.0);
wsPos = a13.xyz;
d13 = min(d13,fCylinder(wsPos, 1.094,2.061));
wsPos = a12.xyz - vec3(.12,1.27,.0);
float d12 = max(-d13,fBox(wsPos,vec3(1.5,1.355,1.551)));
d9 = min(d9,d12);
float d6 = min(d7,d9);
vec4 a14 = a6 - vec4(.463,1.57,1.61,.0);
wsPos = (tr[1] * a14).xyz;
float d14 = fCylinder(wsPos, .105,.046);
wsPos = (tr[2] * a14).xyz;
d14 = min(d14,fCylinder(wsPos, .025,.582));
d6 = min(d6,d14);
float d5 = d6;
float d4 = d5;
d1 = min(d1,d4);
float d0 = min(d1,dot(a0.xyz - vec3(.0,-2.0,.0), vec3(.0,1.0,.0)));
d0 = min(d0, length(p - vec3(0.0, .35, .0)) - 1.5);
d0 = min(d0, -(p.y - 11.15));
return d0;
}