Added egui display

shader/mandelia.frag

@@ -0,0 +1,29 @@
+#define cx_mul(a,b) vec2(a.x*b.x-a.y*b.y, a.x*b.y+a.y*b.x)
+#define cx_mag2(x) dot(x,x)
+
+#define E 2.718281828
+
+uniform int maxiter;
+uniform float escape2;
+
+in vec2 base;
+in vec2 delta;
+
+layout(location = 0) out vec4 diffuseColor;
+
+void main() {
+    vec2 pos = base;
+    int i;
+    for (i = 0; i < maxiter; i++) {
+        if (cx_mag2(pos) > escape2) {
+            break;
+        }
+        pos = cx_mul(pos, pos) + delta;
+    }
+    float mag = cx_mag2(pos);
+    float sm_color = log(log(mag / 2.)) / log(escape2) * 2;
+
+    float shade = i - 1 + sm_color;
+    // TODO: palette mapping
+    diffuseColor = vec4(shade, shade, shade, 1);
+}