Pantheon Benchmark: ModelRift / Gemini Flash 3.0

/* [Global] */

// Level of detail
$fn = 64; // [32:1:128]

/* [Rotunda & Dome] */
rotunda_radius = 21.5;
rotunda_height = 21.7;
oculus_radius = 4.5;
// Number of stepped rings on the dome base
dome_steps = 5; // [3:1:7]
// Prominent radial structural seams
rib_count = 32; // [16:2:64]
// How much the ribs stick out from the dome
rib_height = 0.8; // [0.2:0.1:2.0]
rib_width = 0.7; 

/* [Portico Columns] */
column_span = 34;
column_height = 14.5;
column_radius = 0.95;
capital_flare = 1.55;
// Reduced width of the column base
base_radius = 1.6; 

/* [Entablature & Roof] */
entablature_h = 4.5;
pediment_h = 6.5;

/* [Hidden] */
eps = 0.05;

// Main Assembly
union() {
    color("LightGray") rotunda();
    color("DarkGray") intermediate_block();
    color("Ivory") portico();
}

module rotunda() {
    // The main cylindrical wall
    difference() {
        cylinder(h = rotunda_height, r = rotunda_radius);
        translate([0, 0, -eps])
            cylinder(h = rotunda_height + eps*2, r = rotunda_radius - 2.5);
    }
    
    // The Dome with prononuced Radial Ribs
    translate([0, 0, rotunda_height]) {
        difference() {
            union() {
                // Base Hemisphere
                intersection() {
                    sphere(r = rotunda_radius);
                    cylinder(h = rotunda_radius, r = rotunda_radius);
                }
                
                // 1. Pronounced Radial Ribs (The requested structure)
                intersection() {
                    // Larger sphere defining the rib profile
                    sphere(r = rotunda_radius + rib_height);
                    union() {
                        for(r = [0 : rib_count - 1]) {
                            rotate([0, 0, r * (360 / rib_count)])
                            translate([-rib_width/2, 0, 0])
                            // Ribs extending from center to beyond radius
                            cube([rib_width, rotunda_radius + 2, rotunda_radius + 2]);
                        }
                    }
                }
                
                // 2. Horizontal Stepped Rings
                for(i = [0 : dome_steps - 1]) {
                    translate([0, 0, i * 1.35])
                        cylinder(h = 1.4, 
                                 r1 = rotunda_radius - (i * 0.95), 
                                 r2 = rotunda_radius - (i * 0.95 + 1.2));
                }
            }
            // Hollow interior
            sphere(r = rotunda_radius - 2.5);
            // Oculus (the hole at the top)
            translate([0, 0, rotunda_radius - 4])
                cylinder(h = 10, r = oculus_radius);
        }
    }
}

module intermediate_block() {
    w = column_span + 6;
    h = rotunda_height;
    d = 12;
    translate([-w/2, rotunda_radius - 4, 0]) {
        cube([w, d, h]);
        // Secondary pediment
        translate([w/2, 0, h - eps])
            draw_pediment(w, d, 5.5, framed=false);
    }
}

module portico() {
    y_start = rotunda_radius + 6;
    p_depth = 19;
    total_w = column_span + (base_radius * 2) + 0.5;

    translate([0, y_start, 0]) {
        // Floor
        translate([-total_w/2, 0, 0])
            cube([total_w, p_depth, 1.5]);
        
        // Columns
        spacing = column_span / 7;
        for(x = [0:7]) {
            xp = (-column_span/2) + (x * spacing);
            translate([xp, p_depth - 3.5, 1.5]) column_corinthian();
            if (x == 0 || x == 7 || x == 2 || x == 5) {
                translate([xp, p_depth - 9.5, 1.5]) column_corinthian();
                translate([xp, p_depth - 15.5, 1.5]) column_corinthian();
            }
        }
        
        // Entablature
        translate([-total_w/2, 0, column_height + 1.5]) {
            cube([total_w, p_depth, entablature_h * 0.3]);
            translate([0.5, 0.2, entablature_h * 0.3])
                cube([total_w - 1, p_depth - 0.4, entablature_h * 0.4]);
            translate([-0.8, -0.8, entablature_h * 0.7])
                cube([total_w + 1.6, p_depth + 1.6, entablature_h * 0.3]);
        }
        
        // Main Pediment
        translate([0, 0, column_height + 1.5 + entablature_h - eps])
            draw_pediment(total_w + 1.6, p_depth + 1.6, pediment_h, framed=true);
    }
}

module column_corinthian() {
    cylinder(h = 0.5, r = base_radius);
    translate([0, 0, 0.5])
        cylinder(h = 0.4, r1 = base_radius - 0.1, r2 = column_radius);
    cylinder(h = column_height, r = column_radius);
    translate([0, 0, column_height - 1.2])
        cylinder(h = 1.3, r1 = column_radius, r2 = capital_flare);
    translate([0, 0, column_height])
        cube([capital_flare * 2, capital_flare * 2, 0.5], center=true);
}

module draw_pediment(w, d, h, framed=true) {
    rotate([90, 0, 0])
    translate([0, 0, -d])
    linear_extrude(height = d)
    polygon(points = [[-w/2, 0], [w/2, 0], [0, h]]);
    
    if (framed) {
        frame_t = 1.2;
        color("Ivory")
        translate([0, d, 0]) 
        rotate([90, 0, 0])
        linear_extrude(height = 1.8)
        difference() {
            polygon(points = [[-w/2 - 0.5, -0.2], [w/2 + 0.5, -0.2], [0, h + 0.5]]);
            polygon(points = [[-w/2 + frame_t, 0.8], [w/2 - frame_t, 0.8], [0, h - frame_t]]);
        }
    }
}