Hi Jean-Pierre, > a background bitmap is more like the grid that can be shown or not, > but cannot be plotted, and is not a layer. Layers 29, 30 and 31, not > yet used in Pcbnew, should be left for something related to the board. > A background bitmap is not a board item.
I'm a long-time kicad user and have been championing the use of open-source tools (and kicad) at my work. We are doing very challenging layouts for high density systems. Just about every month the question comes up whether we will need to switch to a commercial program such as Altium to be able to build the next board. The hot points have been: buried vias, controlled annular rings on BGA pads and two-way interface with mechanical CAD. I've finessed the annular ring problem by writing a script to generate custom .mod files based on a textual representation of the required pad stack. Neither Pcbnew nor the 3d display allows visualization of the inner annular rings so we have to plot gerbers to test the output of the program. Messy, but our team is still using kicad... The requirement for the mechanical CAD is that we are designing boards to fit into things like portable WMV players and thin laptops. The PCB often has intricate 3D interferences and precise connector locations. We have to interface with existing holes and flex cables with very limited tolerance for connector placement. Being able to put a precisely scalable bitmap generated from a photograph or a CAD drawing into the PCB editor allows for documenting and placing connectors, routes, and mounting holes with respect to the environment the board is being designed for. Another use for a 2d DXF or PNM overlay would be to allow easy reverse engineering for boards for which CAD files are missing. I had this task to do for a company that needed to replicate Silicon Crystal Furnaces originally built in the early 80's. (The company owned the rights to the furnaces, but all documentation had been destroyed during a buy-out in the 90's). I had to tediously measure and manually place all the connectors to fit the legacy mechanical constraints. A gif underlay of the old assembly would have made the job trivial and the layout self documenting. kind regards, -- Rick Walker _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
