Editing Openai/692fcfd8-4b44-800f-a184-fa098175a6d5 (section)

=== 請直接貼上這份（不會再出錯）： ===

<syntaxhighlight lang="python">from cvzone.HandTrackingModule import HandDetector
import cv2
import math

=== ===== 小工具：距離與角度 ===== ===

def dist2d(a, b):
    """計算 2D 距離（支援 Python 3.7）"""
    return ((a[0] - b[0]) ''' 2 + (a[1] - b[1]) ''' 2) ** 0.5

def angle_between(p1, p2, p3):
    """
    計算夾角 ∠p1-p2-p3（p2 為頂點）
    回傳角度（degree）
    """
    v1 = (p1[0] - p2[0], p1[1] - p2[1])
    v2 = (p3[0] - p2[0], p3[1] - p2[1])

    dot = v1[0] '' v2[0] + v1[1] '' v2[1]
    len1 = math.sqrt(v1[0] ''' 2 + v1[1] ''' 2)
    len2 = math.sqrt(v2[0] ''' 2 + v2[1] ''' 2)

    if len1 == 0 or len2 == 0:
        return 0.0

    cosang = dot / (len1 * len2)
    cosang = max(-1.0, min(1.0, cosang))
    ang = math.degrees(math.acos(cosang))
    return ang

=== ===== CVZone 初始化 ===== ===

cap = cv2.VideoCapture(0)
detector = HandDetector(detectionCon=0.7, maxHands=1)

while True:
    success, img = cap.read()
    if not success:
        break

    hands, img = detector.findHands(img)

    info_lines = []

    if hands:
        hand = hands[0]
        lmList = hand["lmList"]  # 每個 landmark 是 [x,y] 或 [x,y,z]
        handType = hand["type"]

        # --- 畫 21 個點（自動支援 2D/3D）---
        for i, lm in enumerate(lmList):
            x = lm[0]
            y = lm[1]
            # 若有 z 就取，不然給 0
            z = lm[2] if len(lm) > 2 else 0

            cv2.circle(img, (x, y), 5, (0, 0, 255), cv2.FILLED)
            cv2.putText(img, str(i), (x + 5, y - 5),
                        cv2.FONT_HERSHEY_PLAIN, 1, (255, 255, 0), 1)

        # ===== 任務 A：食指彎曲偵測 =====
        # 食指節點：5,6,7
        p_mcp = lmList[5]
        p_pip = lmList[6]
        p_dip = lmList[7]

        # 取 x,y（無論 2D 或 3D）
        p_mcp2 = (p_mcp[0], p_mcp[1])
        p_pip2 = (p_pip[0], p_pip[1])
        p_dip2 = (p_dip[0], p_dip[1])

        ang_index = angle_between(p_mcp2, p_pip2, p_dip2)

        if ang_index > 150:
            index_state = "伸直"
        elif ang_index < 120:
            index_state = "彎曲"
        else:
            index_state = "介於直 / 彎"

        info_lines.append("食指角度: {:.1f} 度 ({})".format(ang_index, index_state))

        # ===== 任務 B：拇指尖 - 食指尖距離 =====
        thumb_tip = lmList[4]
        index_tip = lmList[8]

        d_thumb_index = dist2d(
            (thumb_tip[0], thumb_tip[1]),
            (index_tip[0], index_tip[1])
        )

        if d_thumb_index < 40:
            pinch = "Pinch (捏住)"
        else:
            pinch = "分開"

        info_lines.append("拇指尖-食指尖: {:.1f} ({})".format(d_thumb_index, pinch))

    # ===== 在畫面左上角顯示結果 =====
    y0 = 30
    for line in info_lines:
        cv2.putText(img, line, (10, y0),
                    cv2.FONT_HERSHEY_SIMPLEX, 0.6, (0, 255, 0), 2)
        y0 += 25

    cv2.imshow("21 Landmarks - 運算思維示範版（2D/3D 自動支援）", img)

    if cv2.waitKey(1) & 0xFF == ord("q"):
        break

cap.release()
cv2.destroyAllWindows()

</syntaxhighlight>