Sorting in OpenSCAD

Our first program will demonstrate sorting in OpenSCAD. Here’s the full source code:

// OpenSCAD doesn't have built-in sorting functions, so we'll implement a simple bubble sort

function bubble_sort(arr) = 
    let(n = len(arr))
    [for (i = [0:n-1])
        for (j = [0:n-i-2])
            if (arr[j] > arr[j+1])
                let(temp = arr[j])
                    (arr[j] = arr[j+1], arr[j+1] = temp)
    ][n-1];

// Example usage
strs = ["c", "a", "b"];
sorted_strs = bubble_sort(strs);
echo("Strings:", sorted_strs);

ints = [7, 2, 4];
sorted_ints = bubble_sort(ints);
echo("Ints:   ", sorted_ints);

// Check if a list is sorted
function is_sorted(arr) = 
    len(arr) <= 1 ? true :
    [for (i = [0:len(arr)-2]) 
        if (arr[i] > arr[i+1]) false
    ][0] == undef;

echo("Sorted: ", is_sorted(sorted_ints));

In OpenSCAD, we don’t have built-in sorting functions like in some other languages. Instead, we’ve implemented a simple bubble sort algorithm to demonstrate sorting.

The bubble_sort function takes an array and returns a sorted version of it. This function works for both strings and numbers.

We create two example arrays: one with strings and one with integers. We then sort these arrays using our bubble_sort function and echo the results.

strs = ["c", "a", "b"];
sorted_strs = bubble_sort(strs);
echo("Strings:", sorted_strs);

ints = [7, 2, 4];
sorted_ints = bubble_sort(ints);
echo("Ints:   ", sorted_ints);

We’ve also implemented an is_sorted function to check if an array is already in sorted order. This function returns true if the array is sorted, and false otherwise.

echo("Sorted: ", is_sorted(sorted_ints));

To run this OpenSCAD script, you would typically save it as a .scad file and open it in the OpenSCAD application. The results of the echo statements will be displayed in the console output.

Note that OpenSCAD is primarily a 3D modeling scripting language, so these sorting operations are not typically used for 3D modeling tasks. However, this example demonstrates how you can implement sorting algorithms if needed in your OpenSCAD scripts.