精确包容体(附grip源码)

这些年老是有人在说什么最大盒子、包容体的事情。这很重要吗？可能我不做塑胶模体会不到。现发上一个程序，回报网络。

ENTITY/objct(90000),objct1,objct2,CSYS1
ENTITY/P1,P2,P3
ENTITY/x_plan,xplan,y_plan,yplan,z_plan,zplan
$$这些分别表示三个坐标轴的正负向的平面
NUMBER/selrsp,indrsp,xPt,yPt,zPt
NUMBER/x_mPt,xmPt,y_mPt,ymPt,z_mPt,zmPt,x_max,y_max,z_max
NUMBER/xmax,ymax,zmax,xmin,ymin,zmin
$$表示实体上面的六个极点数据等
NUMBER/inidst,mindst(7)
NUMBER/sign
NUMBER/numobj,numstp
inidst=50000
$$表示把六个定位平面放到工作坐标系的远处
$$ins10:
$$GPOS/'Indicate WCS',xPt,yPt,zPt,indrsp
$$IF/indrsp==1,JUMP/ins10:
$$P1=POINT/xPt,yPt,zPt
$$P2=POINT/xPt+50,yPt,zPt
$$P3=POINT/xPt,yPt+50,zPt
$$CSYS1=CSYS/P1,P2,P3,ORIGIN,P1
$$&WCS=CSYS1
$$&WCSDRW=&YES
$$DELETE/P1,P2,P3
$$xPt=0
$$yPt=0
$$zPt=0
$$ &WCS=&ABS
$$下面创建六个平面
x_plan=PLANE/YZPLAN,-inidst
xplan=PLANE/YZPLAN,inidst
y_plan=PLANE/XZPLAN,-inidst
yplan=PLANE/XZPLAN,inidst
z_plan=PLANE/XYPLAN,-inidst
zplan=PLANE/XYPLAN,inidst
ins2:
MASK/OMIT,10,14,15,25,26,29,45,196,197
$$上面把一些不能用于距离判断的OBJECT滤去
IDENT/'Select an object',objct,CNT,numobj,selrsp $$选择目标体
IF/selrsp==1,JUMP/ins2:
IF/selrsp==2,JUMP/idover:
IF/numobj==0,JUMP/idover:
mindst=RELDST/x_plan,objct(1)
xmin=mindst(4)
mindst=RELDST/xplan,objct(1)
xmax=mindst(4)
mindst=RELDST/y_plan,objct(1)
ymin=mindst(5)
mindst=RELDST/yplan,objct(1)
ymax=mindst(5)
mindst=RELDST/z_plan,objct(1)
zmin=mindst(6)
mindst=RELDST/zplan,objct(1)
zmax=mindst(6)
$$下面求出最小值
DO/overdo:,numstp,1,numobj,1
    mindst=RELDST/x_plan,objct(numstp)
    x_mPt=mindst(4)
    IF/xmin>x_mPt,xmin=x_mPt
    mindst=RELDST/xplan,objct(numstp)
    xmPt=mindst(4)
    IF/xmax<xmPt,xmax=xmPt
    mindst=RELDST/y_plan,objct(numstp)
    y_mPt=mindst(5)
    IF/ymin>y_mPt,ymin=y_mPt
    mindst=RELDST/yplan,objct(numstp)
    ymPt=mindst(5)
    IF/ymax<ymPt,ymax=ymPt
    mindst=RELDST/z_plan,objct(numstp)
    z_mPt=mindst(6)
    IF/zmin>z_mPt,zmin=z_mPt
    mindst=RELDST/zplan,objct(numstp)
    zmPt=mindst(6)
    IF/zmax<zmPt,zmax=zmPt
overdo:
x_mPt=xmin
y_mPt=ymin
z_mPt=zmin
xmPt=xmax
ymPt=ymax
zmPt=zmax
$$objct1 = SOLBLK/ORIGIN,x_mPt,y_mPt,z_mPt,SIZE,xmPt-x_mPt,ymPt-y_mPt,zmPt-z_mPt
DELETE/x_plan
DELETE/y_plan
DELETE/z_plan
DELETE/xplan
DELETE/yplan
DELETE/zplan
$$删除六个参考平面

$$------下面是圆整程序
$$xPt=(x_mPt+xmPt)/2
$$yPt=(y_mPt+ymPt)/2
$$zPt=z_mPt
$$IFTHEN/xPt>=0
$$    sign=1
$$ELSE
$$    sign=-1
$$ENDIF
$$xPt=sign*INTF(100*(ABSF(xPt))+0.5)/100
$$IFTHEN/yPt>=0
$$    sign=1
$$ELSE
$$    sign=-1
$$ENDIF
$$yPt=sign*INTF(100*(ABSF(yPt))+0.5)/100
$$IFTHEN/zPt>=0
$$    sign=1
$$ELSE
$$    sign=-1
$$ENDIF
$$zPt=sign*INTF(100*ABSF(z_mPt)+0.5)/100
$$x_max=INTF(100*ABSF(MAXF(absf(xPt-x_mPt),absf(xPt-xmPt))+0.5))/100
$$y_max=INTF(100*ABSF(MAXF(absf(yPt-y_mPt),absf(yPt-ymPt))+0.5))/100
$$z_max=INTF(100*ABSF(MAXF(absf(zPt-z_mPt),absf(zPt-zmPt))+0.5))/100
$$------以上是圆整程序,对底面中心点圆整到小数点后2位,并求出最大的半长度圆整值

IFTHEN/xmPt-x_mPt==0
    MESSG/'X Axis size of The block is wrong'
    JUMP/idover:
ENDIF
IFTHEN/ymPt-y_mPt==0
    MESSG/'Y Axis size of The block is wrong'
    JUMP/idover:
ENDIF
IFTHEN/zmPt-z_mPt==0
    MESSG/'Z Axis size of The block is wrong'
    JUMP/idover:
ENDIF
objct1 = SOLBLK/ORIGIN,x_mPt,y_mPt,z_mPt,SIZE,xmPt-x_mPt,ymPt-y_mPt,zmPt-z_mPt
xPt=(x_mPt+xmPt)/2
yPt=(y_mPt+ymPt)/2
zPt=z_mPt
P1=POINT/xPt,yPt,zPt
P2=POINT/xPt+50,yPt,zPt
P3=POINT/xPt,yPt+50,zPt
CSYS1=CSYS/P1,P2,P3,ORIGIN,P1
&WCS=CSYS1
&WCSDRW=&YES
DELETE/P1,P2,P3
idover:
HALT

顶，谢谢了

能不能告诉下怎么控制工程图中基本视图的大小比例啊

看贴必回贴!!!!!!

good. thanks

顶起来，…………

不懂grip，不过看上去是沿着xyz轴求的外形尺寸，如果是这样的话，这个用open nx好像一个函数就可以了
/******************************************************************************
Returns the bounding box information of wireframe and solid type objects
aligned to a CSYS.

Wireframe objects include lines, arcs, splines, and conics.  Solid type
objects include bodies, faces, and edges.  Bounding box values are
returned in absolute coordinate values according to where the object
exists in the part file and aligned to the input CSYS.

If you call this function with an occurrence, the bounding box
of the underlying geometry is transformed into assembly space.

Use occurrence object tags when working in an assembly context and prototype
object tags when working in non-assembly situations. Passing in a prototype
object tag when in an assembly may produce undesired results.

The csys_tag should always be in the context of the current work part.

To derive the corner points, use the X,Y,X components of the
min_corner  and then add the X,Y,Z components of the directions multiplied
by the X,Y,Z distances. For Example, to derive the 2 corner points:
  corner_pts[2][3]

  corner_pts[0][0] = min_corner[0]
  corner_pts[0][1] = min_corner[1]
  corner_pts[0][2] = min_corner[2]
  for i = 0 -> 2 inclusive
    corner_pts[1][i] = min_corner[i]
    for j = 0 -> 2 inclusive
      corner_pts[1][i] += directions[j][i] * distances[j]

While a more accurate box is produced, processing time may be increased
significantly.

Environment: Internal  and  External
See Also:
History: Originally released in NX V4.0
******************************************************************************/
extern UFUNEXPORT int UF_MODL_ask_bounding_box_exact(
tag_t   object ,          /* <I>
                             Object identifier of object to ask bounding box.
                          */
tag_t   csys_tag,         /* <I>
                             CSYS to use for box alignment.
                             NULL_TAG - Use Work CSYS
                          */
double  min_corner[3],    /* <O>
                             Minimum corner of box of object.
                             [0] - minimum x value
                             [1] - minimum y value
                             [2] - minimum z value
                          */
double  directions[3][3], /* <O>: direction vectors of bounding box
                             [0][] - X Direction
                             [1][] - Y Direction
                             [2][] - Z Direction */
double  distances[3]      /* <O>
                             Distances to move along directions of CSYS
                             to derive all points of the bounding box.
                             [0] - X distance value
                             [1] - Y distance value
                             [2] - Z distance value
                          */
);

谢谢楼主的分享~~

谢谢楼主的分享~~

恩，是的
最小包围盒是个几何难题
目前较多的做法是采用三角网格模型来计算。

UG提供的方法只能以XOY上建立包围盒，不是真正的OBB有向包围盒

如果有人想研究，一起切磋啊，呵呵