按推荐建议，继续执行

结论：继续按 LinuxCNC 源码直接复用路线推进，新增 SCARA 运动学源码的 vendored 同步、switchkins native 探针、source probe 覆盖和复用文档，并通过 native 验证。

wasm-port/vendor/linuxcnc/src/emc/kinematics/scarakins.c

@@ -0,0 +1,238 @@
+/*****************************************************************
+* Description: scarakins.c
+*   Kinematics for scara typed robots
+*   Set the params using HAL to fit your robot
+*
+*   Derived from a work by Sagar Behere
+*
+* Author: Sagar Behere
+* License: GPL Version 2
+* System: Linux
+*
+* Copyright (c) 2003 All rights reserved.
+*
+* Last change:
+*******************************************************************
+*/
+
+#include <rtapi.h>
+#include <rtapi_math.h>
+#include <rtapi_string.h>
+#include <hal.h>
+#include <kinematics.h>
+
+#include "switchkins.h"
+
+struct scara_data {
+    hal_float_t *d1, *d2, *d3, *d4, *d5, *d6;
+} *haldata = 0;
+
+/* key dimensions
+
+   joint[0] = Entire arm rotates around a vertical axis at its inner end
+                which is attached to the earth.  A value of zero means the
+                inner arm is pointing along the X axis.
+   D1 = Vertical distance from the ground plane to the center of the inner
+                arm.
+   D2 = Horizontal distance between joint[0] axis and joint[1] axis, ie.
+                the length of the inner arm.
+   joint[1] = Outer arm rotates around a vertical axis at its inner end
+                which is attached to the outer end of the inner arm.  A
+                value of zero means the outer arm is parallel to the
+                inner arm (and extending outward).
+   D3 = Vertical distance from the center of the inner arm to the center
+                of the outer arm.  May be positive or negative depending
+                on the structure of the robot.
+   joint[2] = End effector slides along a vertical axis at the outer end
+                of the outer arm.  A value of zero means the end effector
+                is at the same height as the center of the outer arm, and
+                positive values mean downward movement.
+   D4 = Horizontal distance between joint[1] axis and joint[2] axis, ie.
+                the length of the outer arm
+   joint[3] = End effector rotates around the same vertical axis that it
+                slides along.  A value of zero means that the tooltip (if
+                offset from the axis) is pointing in the same direction
+                as the centerline of the outer arm.
+   D5 = Vertical distance from the end effector to the tooltip.  Positive
+                means the tooltip is lower than the end effector, and is
+                the normal case.
+   D6 = Horizontal distance from the centerline of the end effector (and
+                the joints 2 and 3 axis) and the tooltip.  Zero means the
+                tooltip is on the centerline.  Non-zero values should be
+                positive, if negative they introduce a 180 degree offset
+                on the value of joint[3].
+*/
+
+#define D1 (*(haldata->d1))
+#define D2 (*(haldata->d2))
+#define D3 (*(haldata->d3))
+#define D4 (*(haldata->d4))
+#define D5 (*(haldata->d5))
+#define D6 (*(haldata->d6))
+
+/* joint[0], joint[1] and joint[3] are in degrees and joint[2] is in length units */
+static
+int scaraKinematicsForward(const double * joint,
+                      EmcPose * world,
+                      const KINEMATICS_FORWARD_FLAGS * fflags,
+                      KINEMATICS_INVERSE_FLAGS * iflags)
+{
+    (void)fflags;
+    double a0, a1, a3;
+    double x, y, z, c;
+
+/* convert joint angles to radians for sin() and cos() */
+
+    a0 = joint[0] * ( PM_PI / 180 );
+    a1 = joint[1] * ( PM_PI / 180 );
+    a3 = joint[3] * ( PM_PI / 180 );
+/* convert angles into world coords */
+
+    a1 = a1 + a0;
+    a3 = a3 + a1;
+
+    x = D2*cos(a0) + D4*cos(a1) + D6*cos(a3);
+    y = D2*sin(a0) + D4*sin(a1) + D6*sin(a3);
+    z = D1 + D3 - joint[2] - D5;
+    c = a3;
+
+    *iflags = 0;
+    if (joint[1] < 90)
+        *iflags = 1;
+
+    world->tran.x = x;
+    world->tran.y = y;
+    world->tran.z = z;
+    world->c = c * 180 / PM_PI;
+
+    world->a = joint[4];
+    world->b = joint[5];
+
+    return (0);
+} //scaraKinematicsForward()
+
+static int scaraKinematicsInverse(const EmcPose * world,
+                                  double * joint,
+                                  const KINEMATICS_INVERSE_FLAGS * iflags,
+                                  KINEMATICS_FORWARD_FLAGS * fflags)
+{
+    double a3;
+    double q0, q1;
+    double xt, yt, rsq, cc;
+    double x, y, z, c;
+
+    x = world->tran.x;
+    y = world->tran.y;
+    z = world->tran.z;
+    c = world->c;
+
+    /* convert degrees to radians */
+    a3 = c * ( PM_PI / 180 );
+
+    /* center of end effector (correct for D6) */
+    xt = x - D6*cos(a3);
+    yt = y - D6*sin(a3);
+
+    /* horizontal distance (squared) from end effector centerline
+        to main column centerline */
+    rsq = xt*xt + yt*yt;
+    /* joint 1 angle needed to make arm length match sqrt(rsq) */
+    cc = (rsq - D2*D2 - D4*D4) / (2*D2*D4);
+    if(cc < -1) cc = -1;
+    if(cc > 1) cc = 1;
+    q1 = acos(cc);
+
+    if (*iflags)
+        q1 = -q1;
+
+    /* angle to end effector */
+    q0 = atan2(yt, xt);
+
+    /* end effector coords in inner arm coord system */
+    xt = D2 + D4*cos(q1);
+    yt = D4*sin(q1);
+
+    /* inner arm angle */
+    q0 = q0 - atan2(yt, xt);
+
+    /* q0 and q1 are still in radians. convert them to degrees */
+    q0 = q0 * (180 / PM_PI);
+    q1 = q1 * (180 / PM_PI);
+
+    joint[0] = q0;
+    joint[1] = q1;
+    joint[2] = D1 + D3 - D5 - z;
+    joint[3] = c - ( q0 + q1);
+    joint[4] = world->a;
+    joint[5] = world->b;
+
+    *fflags = 0;
+
+    return (0);
+} // scaraKinematicsInverse()
+
+#define DEFAULT_D1 490
+#define DEFAULT_D2 340
+#define DEFAULT_D3  50
+#define DEFAULT_D4 250
+#define DEFAULT_D5  50
+#define DEFAULT_D6  50
+
+static int scaraKinematicsSetup(const  int   comp_id,
+                                const  char* coordinates,
+                                kparms*      kp)
+{
+    (void)coordinates;
+    int res=0;
+
+    haldata = hal_malloc(sizeof(*haldata));
+    if (!haldata) goto error;
+
+    res += hal_pin_float_newf(HAL_IN, &(haldata->d1), comp_id,"%s.D1",kp->halprefix);
+    res += hal_pin_float_newf(HAL_IN, &(haldata->d2), comp_id,"%s.D2",kp->halprefix);
+    res += hal_pin_float_newf(HAL_IN, &(haldata->d3), comp_id,"%s.D3",kp->halprefix);
+    res += hal_pin_float_newf(HAL_IN, &(haldata->d4), comp_id,"%s.D4",kp->halprefix);
+    res += hal_pin_float_newf(HAL_IN, &(haldata->d5), comp_id,"%s.D5",kp->halprefix);
+    res += hal_pin_float_newf(HAL_IN, &(haldata->d6), comp_id,"%s.D6",kp->halprefix);
+    if (res) { goto error; }
+
+    D1 = DEFAULT_D1;
+    D2 = DEFAULT_D2;
+    D3 = DEFAULT_D3;
+    D4 = DEFAULT_D4;
+    D5 = DEFAULT_D5;
+    D6 = DEFAULT_D6;
+
+    return 0;
+
+error:
+    return -1;
+} // scaraKinematicsSetup()
+
+int switchkinsSetup(kparms* kp,
+                    KS* kset0, KS* kset1, KS* kset2,
+                    KF* kfwd0, KF* kfwd1, KF* kfwd2,
+                    KI* kinv0, KI* kinv1, KI* kinv2
+                   )
+{
+    kp->kinsname    = "scarakins"; // !!! must agree with filename
+    kp->halprefix   = "scarakins"; // hal pin names
+    kp->required_coordinates = "xyzabc"; // ab are scaragui table tilts
+    kp->allow_duplicates     = 0;
+    kp->max_joints = strlen(kp->required_coordinates);
+
+    rtapi_print("\n!!! switchkins-type 0 is %s\n",kp->kinsname);
+    *kset0 = scaraKinematicsSetup;
+    *kfwd0 = scaraKinematicsForward;
+    *kinv0 = scaraKinematicsInverse;
+
+    *kset1 = identityKinematicsSetup;
+    *kfwd1 = identityKinematicsForward;
+    *kinv1 = identityKinematicsInverse;
+
+    *kset2 = userkKinematicsSetup;
+    *kfwd2 = userkKinematicsForward;
+    *kinv2 = userkKinematicsInverse;
+
+    return 0;
+} // switchkinsSetup()