$fn=64;

// --- Parameters ---
panel_width = 150;      // Total width of the backdrop
panel_height = 200;     // Height of the backdrop above baseplate
panel_thickness = 3;    // Thickness of the main panel

tab_width = 130;        // Width of the insertion tab
tab_drop = 12;          // Depth the tab inserts into the baseplate
tab_thickness = 2.6;    // Tab thickness (slightly thinner than panel for slot clearance)

corner_radius = 8;      // Radius of the top corners

// --- Assembly ---
// The model is designed to print flat on its back (Z=0) without supports.
union() {
    // Main Backdrop Panel
    hull() {
        // Top left rounded corner
        translate([-panel_width/2 + corner_radius, panel_height - corner_radius, 0])
            cylinder(r=corner_radius, h=panel_thickness);
        
        // Top right rounded corner
        translate([panel_width/2 - corner_radius, panel_height - corner_radius, 0])
            cylinder(r=corner_radius, h=panel_thickness);
            
        // Flat bottom edge
        translate([-panel_width/2, 0, 0])
            cube([panel_width, 1, panel_thickness]);
    }
    
    // Mounting Tab
    hull() {
        // Top of the tab (overlaps slightly into the main panel for a manifold union)
        translate([-tab_width/2, -0.1, 0])
            cube([tab_width, 1.2, tab_thickness]);
            
        // Bottom of the tab (chamfered sides for easy insertion into baseplate)
        translate([-tab_width/2 + 3, -tab_drop, 0])
            cube([tab_width - 6, 1, tab_thickness]);
    }
}