Added i/o type for 3D textures (takes xyz+color index as input)

addons/material_maker/nodes/io_types.mmt

@@ -70,6 +70,15 @@
 			{ "type":"sdf3d", "expr":"($(value)).x" }
 		],
         "color":{ "r":1.0, "g":0.0, "b":0.0, "a":1.0 }
+    },
+	{
+        "name":"tex3d",
+        "label":"TEX3D",
+        "type":"vec3",
+        "paramdefs":"vec4 p",
+        "params":"p",
+        "slot_type":3,
+        "color":{ "r":1.0, "g":0.0, "b":0.0, "a":1.0 }
     },
     {
         "name":"any",

addons/material_maker/nodes/preview_tex3d.shader

@@ -0,0 +1,37 @@
+float calcdist(vec3 p) {
+    return length(p)-0.4;
+}
+
+vec3 calcColor(vec4 uv) {
+    $(code)
+    return $(value);
+}
+
+float raymarch(vec3 ro, vec3 rd) {
+    float d=0.0;
+    for (int i = 0; i < 50; i++) {
+        vec3 p = ro + rd*d;
+        float dstep = calcdist(p);
+        d += dstep;
+        if (dstep < 0.0001) break;
+    }
+    return d;
+}
+vec3 normal(vec3 p) {
+    float d = calcdist(p);
+    float e = .0001;
+    vec3 n = d - vec3(calcdist(p-vec3(e, 0.0, 0.0)), calcdist(p-vec3(0.0, e, 0.0)), calcdist(p-vec3(0.0, 0.0, e)));
+    return normalize(n);
+}
+
+void fragment() {
+    vec2 uv = UV-vec2(0.5);
+    vec3 p = vec3(uv, 2.0-raymarch(vec3(uv, 2.0), vec3(0.0, 0.0, -1.0)));
+    vec3 n = normal(p);
+    vec3 l = vec3(5.0, 5.0, 10.0);
+    vec3 ld = normalize(l-p);
+    float o = step(p.z, 0.001);
+    float shadow = 1.0-0.75*step(raymarch(l, -ld), length(l-p)-0.01);
+    float light = 0.3+0.7*dot(n, ld)*shadow;
+    COLOR = vec4(calcColor(vec4(p, 0.0))*light, 1.0);
+}