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Getting lines on Assembly Top for a symbol

HighFive

Hello friends,

I’m in need of assistance. I’m new to Skill, but not to programming, and I’ve been reading the manual. Unfortunately the hierarchy of objects in Allegro is still clear as mud to me.

What I’m trying to do:

automatically size, and place, the RefDes in the center of the “box” on Assembly top. By “box” I mean the set of lines creating the mechanical outline of the physical component, not synonymous with the bounding box of the symbol. It is important to get the collection of lines that compose this box, so the RefDes text block can be set appropriately to fit within the lines. For instance I want to size the RefDes appropriately so it will fit inside an 0402 resistor. 

This is ultimately to automate assembly drawing creation, within the context of a BRD. I’ve noted other scripts that place the RefDes in the symbol center, but I haven’t seen any that find the bounding box of lines on assembly top, to size the RefDes appropriately. So I could use a little direction. Here’s what I’ve got so far: I'm able to grab all the symbols, print their names, and list their paths, but thats as far as I've got. I'm trying to figure out how to extract the line width and the line endpoints. 

    allSymbols = axlDBGetDesign()->symdefs
    foreach(symbol allSymbols 
        children = setof(children symbol->children index(children->layer "PACKAGE GEOMETRY/ASSEMBLY_TOP") )
        foreach( child children
            printf("\t\t")
            printf(child->objType)
            printf("\n")

            if( child->objType == "path" && child->nSegs != nil then
                printf("\t\t\t#segments in path: ")
                printf("%d" child->nSegs)
                printf("\n")
            )
        )
    )

I haven’t been able to grab any useful properties from each path however. The only thing I’ve been able to extract is the # of segments. All other methods I’ve tried to run extracting info from each path has been fruitless.

For instance trying to list the segments doesnt work:

   if( child->objType == "path" && axlPathGetPathSegs( child ) != nil then
                printf("\t\t\tSegments: %s\n" axlPathGetPathSegs( child) )
            )
I'm not sure if I don't have the proper context for these paths, or I'm using the wron methods, or what. Any assistance would be very much appreciated!

  • After getting the list of children, try something like this:

    (DataList = (axlDBGetExtents children nil))
    (llx = xCoord( lowerLeft(DataList)))
    (lly = yCoord( lowerLeft(DataList)))
    (urx = xCoord( upperRight(DataList)))
    (ury = yCoord( upperRight(DataList)))
    (Dx = (urx - llx))
    (Dy = (ury - lly))

  • in reply to DavidJHutchins

    Awesome thank you very much David!

    I just tried out the code, and it works well. Its almost what I want-

    This code returns the bounding box for all lines on Assembly Top, per placed symbol. If possible, I'd like to get the bounding box for each individual line, so that I can determine which size RefDes will fit. For instance, on An SOIC componenent, there's lines forming the body of the part, and lines forming the pins. The bounding box for all lines would include area covered by the pins, and I'd like the Refdes to fit inside the body of the part. Not a good example but you get the idea. For some other parts, say an SMB jack, theres lines forming the body, but then a circle at the center for center pins, where a RefDes would interfere. Is it possible to get the coordinate info for each line?

    I guess another way of looking at it would be- starting at the symbol center, what are the coordinates for the largest bounding box that can fit before intersecting a line on Assembly Top?

    Thank you so much brother! Cheers!

  • in reply to HighFive

    I would try geting the overall place_bound shape, then remove the bounding-box of every pin in the symbol, then compare the lines against the resulting shape with axlGeoPointShapeInfo()

  • Great,

    Thank you very much David. I really appreciate your responses. I ended up figuring out how to do what I wanted to- getting all the lines on Assembly Top on a per symbol basis. Now I'm focusing on finding the largest bunding box that can fit inside the lines, starting from the center of the symbol, before intersecting a line. That bounding box will be the max size of the text. I'll update the code here when complete. Here's what I've done so far to get all lines on assembly top and print out a bunch of info:

    procedure(Get_Lines()

        axlClearSelSet() 
        axlSetFindFilter(?enabled '("NOALL" "SYMBOLS") ?onButtons '("SYMBOLS"))
        symbol_list = axlGetSelSet(axlAddSelectAll() )
        axlClearSelSet() 
        foreach( symbol symbol_list
            ;sym = car(setof(obj, refdes ->children, obj ->layer == "REF DES/SILKSCREEN_TOP"))
            if( symbol->name != nil then
                printf("Footprint: %s " symbol->name)
            else
                printf(" no name ")
            )

            if( symbol->refdes != nil then
                printf("   RefDes:  %s    " symbol->refdes)
            )

            if( symbol->objType != nil then
                printf(" type: %s\n" symbol->objType)

                else
                    printf("\n")
            )
            
            children = symbol->children
            foreach( child children
               printf("\t\"%s\" on  %s\n" child->objType child->layer)
               if( child->objType == "path" then
                    path = child
                    printf("\t\taxlDbidName: %s\n" axlDbidName( path ) )
                    
                    line_segments = path->segments
                    if( path->hasArcs != nil then
                        printf("\t\tPath has Arcs in it\n")
                    else
                        printf("\t\tpath has no Arcs in it\n")
                    )
                    foreach(segment line_segments
                        ;print(segment->startEnd)
                        printf("\t\t%L\n" segment->startEnd)
                        printf("\t\tpath type:  %s\n" segment->objType)
                        printf("\t\twidth:  %.4f\n" segment->width)
                        if( segment->objType == "line" then
                            printf("\t\tlinetype:  %s\n" segment->lineType)
                            if( segment->font != nil then
                                printf("\t\tfont:  %s\n" segment->font)
                            )
                        )
                        if( segment->objType == "arc" then
                            if( segment->isCircle == nil then
                                seg_is_circle = "false"
                            else
                                seg_is_circle = "true"
                            )
                            printf("\t\tisCircle:  %s\n" seg_is_circle)
                            
                            if( segment->isClockwise == nil then
                                seg_is_clockwise = "false"
                            else
                                seg_is_clockwise = "true"
                            )

                            printf("\t\tisClockwise:  %s\n" seg_is_clockwise)
                            printf("\t\tCenter:  %L\n" segment->xy)
                        )
                    )
                    printf("\t\tnSegs: %d\n" child->nSegs)
                )   
            )
            printf("\n\n")
        )
    )
    It took awhile to figure out how to get all the lines with path->segments. The documentation for data object hierarchy is extremely confusing. I can't remember where, but I actually found documentation suggesting the child reference was path->Segments, with a capital "S". Regardless, I've got the lines now so I'm happy. I'll post a followup with my finished code once it is complete. 
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