3D_Etch-A-Sketch

#!/usr/bin/env python3
import os
import re
import serial
import subprocess
from time import sleep
import pyautogui

# CONFIG
PORT = "/dev/ttyACM0"
BAUD = 115200
OUTPUT_FILE = "lego.scad"
BRICK_MODULE_FILE = "brick.scad" # the model brick
placed_bricks = set()


X_STEP = 16   # half of 32 mm
Y_STEP = 8     # half of 16 mm
Z_STEP = 9.6  # full height

# Global position tracker [x, y, z]
current_position = None
current_rotation = 0 # R value modulo 4 (i.e. 0, 1, 2, 3)

# Rather than including brick.scad, lets just write it.
def brick_scad():
    with open('b.scad', 'w') as f:
        f.write('// brick.scad\nw = 8; \n h = 9.6; \n module lego_brick(studs=4){ \n $fn = 80; \n width = 8 * studs; \n cube([width,16,9.6]); \n for (xpos=[4 : 8 : width-4]){ \n translate([xpos,4,1.7]) cylinder(h=9.6,d=4.8); \n translate([xpos,12,1.7]) cylinder(h=9.6,d=4.8); \n } \n } \n')


# this addresses an issue in open scad around load large files, by ensuring the output file is always blank
def lego_scad():
    with open('lego.scad','w') as f:
        f.write('use <brick.scad>;\n')

brick_scad()
lego_scad()

def launch_openscad():
    subprocess.Popen(["openscad", OUTPUT_FILE])
    sleep(2)

#def update_scad_with_brick(x, y, z, rotation_deg):
def update_scad_with_brick(x, y, z):
    #brick_key = (x, y, z, rotation_deg)
    brick_key = (x, y, z)
    if brick_key in placed_bricks:
        print(f"[SKIP] Brick already placed at {brick_key}")
        return

    placed_bricks.add(brick_key)
    #brick_line = f"rotate([0,0,{rotation_deg}]) translate([{x}, {y}, {z}]) lego_brick(4);\n"
    brick_line = f"translate([{x}, {y}, {z}]) lego_brick(2);\n"
    try:
        with open(OUTPUT_FILE, "a") as f:
            f.write(brick_line)
    except Exception as e:
        print("Error writing brick to SCAD file:", e)
        return

    print(f"[SCAD] Added brick at {brick_key}")
    pyautogui.press("f5")
    sleep(0.2)

'''
def update_scad_with_brick(x, y, z, rotation_deg):
    brick_line = f"rotate([0,0,{rotation_deg}]) translate([{x}, {y}, {z}]) lego_brick(4);\n"

    try:
        with open(OUTPUT_FILE, "a") as f:
            f.write(brick_line)
    except Exception as e:
        print("Error writing brick to SCAD file:", e)
        return

    print(f"Added brick at x={x} y={y} z={z} rotation={rotation_deg}")
    pyautogui.press("f5")
    sleep(0.2)
'''
def main():
    global current_position, current_rotation

    try:
        # Ensure SCAD file starts with module include
        if not os.path.exists(OUTPUT_FILE):
            with open(OUTPUT_FILE, "w") as f:
                f.write(f'use <{BRICK_MODULE_FILE}>;\n')

        ser = serial.Serial(PORT, BAUD, timeout=1)
        print("Listening to Teensy on", PORT)

        launch_openscad()
        last_positions = [0, 0, 0, 0, 0]  # X, Y, Z, R, V

        while True:
            line = ser.readline().decode(errors="ignore").strip()

            if line:
                print("RAW:", line)  # Log all input for debugging

            if line.startswith("X:"):
                match = re.match(r"X:\s*(-?\d+), Y:\s*(-?\d+), Z:\s*(-?\d+), R:\s*(-?\d+), V:\s*(-?\d+)", line)

                if match:
                    new_positions = list(map(int, match.groups()))
                    if new_positions != last_positions:
                        print(f"[ENCODER UPDATE] X={new_positions[0]} Y={new_positions[1]} Z={new_positions[2]} R={new_positions[3]} V={new_positions[4]}")
                        # Compute real-world position
                        x_real = new_positions[0] * X_STEP
                        y_real = new_positions[1] * Y_STEP
                        z_real = new_positions[2] * Z_STEP
                        #angle = (new_positions[3] % 4) * 90
                        #brick_key = (x_real, y_real, z_real, angle)
                        brick_key = (x_real, y_real, z_real)

                        if brick_key not in placed_bricks:
                            print(f"[AUTO-DRAW] Placing brick at {brick_key}")
                            #update_scad_with_brick(x_real, y_real, z_real, angle)
                            update_scad_with_brick(x_real, y_real, z_real)
                        else:
                            print(f"[SKIP] Brick already placed at {brick_key}")

                        last_positions = new_positions
                        current_position = new_positions[0:3]
                        current_rotation = new_positions[3] % 2 # becuase only only 0,90 mater. its a regular block.

                else:
                    print("[WARN] Failed to parse encoder line:", line)
            '''
            elif line == "E#0 pressed":
                print("[BUTTON] E#0 (View) pressed")
            elif line == "E#1 pressed":
                print("[BUTTON] E#1 (Z) pressed")
            elif line == "E#2 pressed":
                print("[BUTTON] E#2 (X) pressed")
            elif line == "E#3 pressed":
                if current_position is None:
                    print("[SKIP] No position data yet ignoring button press")
                    continue
                print("[BUTTON] E#3 (Y / PLACE) pressed  Drawing brick")

                x_real = current_position[0] * X_STEP
                y_real = current_position[1] * Y_STEP
                z_real = current_position[2] * Z_STEP
                angle = current_rotation * 90

                print(f"[DRAW] Brick @ X:{x_real} Y:{y_real} Z:{z_real} Angle:{angle}")
                update_scad_with_brick(x_real, y_real, z_real, angle)

            elif line == "E#4 pressed":
                print("[BUTTON] E#4 (Rotate) pressed")
            '''

    except KeyboardInterrupt:
        print("\nInterrupted by user. Exiting.")
        try:
            if ser and ser.is_open:
                ser.close()
                print("[INFO] Serial port closed.")
        except Exception as e:
            print(f"[WARN] Error closing serial port: {e}")
if __name__ == "__main__":
    main()
'''
Ok this is a fully functional 3D drawing program, but its still buggy,
the IO is a teensy 4.0, with 4 rotary encoders, the IO can easily overload
both the i2C bus it is on, and the program Openscad, which it uses to draw the 3D
models.

Need to make improvements, but it do work. ... provided I don't alter the functions of
the serial commands the MCU provides. a fresh build of open scad can help
performance, by adjusting the rendering properties to manifold, and by increasing the
number of objects / RAM openscad uses to process objects.

There is also a bug in openscad, where manifold only re-renders objects,
this means, dont load large files initially, but reloading them is fine.
Still waiting for gooners at openscad to fix the issue.
'''