[Jan de Lint]

Dear all,
how does one create a simple graph in BMP or PNG format?
GDI+?
Can a metafile.emf simply be converted?
I need to output some performance characteristics graphically.
Thanks,
]an

[Kari Rastas]

Well basically creating a graph is easy. You create a picture (vpi::pictOpen), make the wanted draw operations (axis, axis numbers, header, observations etc) and finally save the picture using vip::pictSave. The picture is saved in BMP format.

Saving the picture directly in PNG (or JPEG etc) format could be done like this

Code: Select all

    savePictureToFile(Picture,FileName) :-
        vpi::pictSave(Picture,"x.bmp"),
        gdiplus_api::startup(),
        Image = gdiPlus::loadImageFromFile("x.bmp"),
        TYPE = imageType(fileName::getExtension(FileName)),
        CLSID = gdiPlus_api::gdipTryGetImageEncoder(TYPE),
        gdiplus_api::checkStatus(gdiPlus_native::gdipSaveImageToFile(Image,FileName,CLSID,null),"gdipSaveImageToFile"),
       gdiPlus_api::gdipDisposeImage(Image),
       gdiplus_api::shutdown(),
        !.

GDI+ is a real jungle and if your needs are simply to draw a simple chart I would recommend you forget GDI+. During the past years I have occasionally worked with the GDI+ "problem". I have had no big difficulties in producing rather complex GDI+ charts or drawings on the screen, but when it comes to saving the GDI+ picture I have not managed to find out how it is done. I have tried to figure out it several times and then got frustrated in the lack of success and have "forgotten" GDI+ for the next 6 months.

[Jan de Lint]

Thanks Kari,
I'll try to explore the possibilities along the lines you suggest.
The VIP picturedraw example provides the opposite from what I need. The example assumes BMP and JPG files on disk and displays them on the screen.
OpenGL and the likes seem to be a bit heavy for my purpose, to use an understatement.
]an

[Paul Cerkez]

Jan,
the vpi picture predicates are relatively easy to use from scratch.

here is a short example code that I have used to create a terabytes worth of sample images for my NN research.

Code: Select all

    
class facts - text_to_encode
    picWin : pictureCanvas := erroneous.
    controlRCT : rct := rct(0,0,256,256).
 
...
 
 
clauses
drawGraphicMorse(INint):-
 
...
        controlRCT = rct(_X1,_Y1,X2,Y2),
        picWin := pictureCanvas::new(256,256),
 
% commented out due to te 9,944 'limit'
%        picWin : setFont(vpi::fontCreateByName("Courier New",titleFontSize)),
 
% sets black on white
        Fore = color_black,
        Back = color_white,
 
% sets the inverse white on black
%        Fore = color_white,
%        Back = color_black,
 
% sets random colors for front and back
%        randomColor(Fore, Back),
 
% Sets greys for front and back
%        randomGrey(Fore, Back),
 
        picWin : setForeColor(Fore),
        picWin : setbackColor(Back),
        picWin : setBrush(brush(pat_Solid, Back)),
        picWin : drawFloodFill(pnt(1,1), Back),
 
...
 
        XT =convert(integer, math::random(220)),
        YT = convert(integer, math::random(220)),
 
% draw the text .... 
       picWin : drawTextInRect(rct(XT,YT,X2,Y2),MOrse, [dtext_Left ,dtext_Wordbreak]),
 
% save the image
        PIC = picWin : getPicture(),
        wordname(RAW, NAME),
        FileName = string::concat("MORSE ",/* RAW*/NAME, "-", IN, ".BMP"),
        vpi::pictSave(PIC, FileName),
 
        fail.
 
drawGraphicMorse(_INint).

P.

[Jan de Lint]

Hi Paul,
this was not fun, but it is improving
Thanks,
]an

[Jan de Lint]

I just learned about the QGoogleVisualizationAPI
Perhaps even more fun!
If succesful I'll extend the examples in the VPcURL package.
]an

[Ferenc Nagy]

Hi,
I suspect that this line is wrong in Kari's solution

Code: Select all

TYPE = imageType(fileName::getExtension(FileName)),