DPlot

Thanks david,

i'll go that route.

jerry

Hi,

i am stuck and wonder if you can help.

i am using Jr to draw a plot in a picture box using your sample code in VB6. i get exactly the plot i want. now i want to save that as a bitmap file and can't seem to make that work .

any ideas?

thanks
jerry

Maybe I finally get it, sometimes i need things to be painfully obvious,

I'll play around with this some more and see what happens, i'l try using the metrics to scale and see of the results are what i expect.

thanks again,
jerry

Ok, i posted that so you could read what some of my thinking has been.

so if i use the hll, vll etc, to determine the pixel locations of the corners of the plot then is there a way to get the x and y values of the same corners? (or can i force them to be some x and y values that i want by using ...

Keep in mind that those are the pixel values of the corners of the plot, though - not the extents of the entire plot. So this still may not be quite what you have in mind.


i don't know what you mean by "not the extents of the entire plot." do you mean that it give the corners of the plot but not ...

i don't see the problem, here is the code i'm using:

' try to get the metrics without drawing the plot
If (hBitmap <> 0) Then
ret = DeleteObject(hBitmap)
hBitmap = 0
End If
If DocNum <> 0 Then
ret = DPlot_Command(DocNum, "[FileClose()]")
End If
DocNum = DPlot_Plot(d, 0&, Node(0, 0), cmds ...

LOL,

i had a hunch it was something like that!

now i have an idea where to look in the code. i used the DPM to get the corners of the plot and then use the distance between the corners to size the bitmap. must be an error in the formula or something unexpected in the data, this data came from down ...

David,

i have gotten the following:

Error in CreateCompatibleBitmap=0x00000008, Size 802x616744

i suspect there is a size issue, can you fill me in on the error and any limitations that i need to work around?

thanks
jerry

David,

as you can imagine i have been reading the DPlotJr help file alot the last few days :lol:

and i notice a bug of sorts: when you open the help file the window is taller than the viewable hieght of my screen. As a result the scroll down button is not accesible.

no big deal, but a bit ...

David,

i started to type another question:


This is so frustrating, every time i think its working and move on a new glitch comes in!

i'm sure you don't have that happen though.....

OK, here i am, using the plotmetrics works fine except that i can't get the scale to work quite right.

But ...

OK, David,

now that's the ticket. i've got what i need, i just need to check the pixels per inch of the picturebox on the form load event and then i can size the plot accordingly once the file to be plotted has been selected!

by the way on the way to get pizza i realized that i don't need to set ...

On a quick glance i think i see how this works.

I will try it out after lunch, if i can get (wx,wy) in this way then i'm home free and i only need to scale the bitmap large enough to give at least one meter per pixel.

thanks, pizza time....

jerry

OK,

i'll take a look at that, i think you understand just what i'm trying to do.

thanks
jerry

I found this which may lead to a solution:

Return the number of twips per pixel for an object measured horizontally (TwipsPerPixelX) or vertically (TwipsPerPixelY).

Syntax

object.TwipsPerPixelX

object.TwipsPerPixelY

The object placeholder represents anobject expression that evaluates to an ...

"strange VB gizmo"

that made me laugh, but twips do come into play, possibly.

here is what i am working on, i have been playing with it this morning,

if i plot using [ManualScale(1000,1000,2000,2000)] then the bitmap represents a section of the plane 1000 units wide and 1000 units high.

so i ...

David,

can you tell me the number of pixels per inch that a bitmap is created with when i use DPlot_GetBitmapEx ?

i think i have my scaling problem solved once i know that.

thanks
jerry

OH YEAH!!!!


I finally got it,

well OK: YOU finally got it for me, now lets see if i can get the rest of this thing done this week.

Thanks again,
Jerry

David,

thanks a bunch, i got 1. and 2. squared away.

3 however, hmmmm....

i can turn off the axes in DplotJr using the menu, i could not find an equivalent command to do the same, does one exsist? if not, now worries because i found where i can set the axes color to white which will be an ...

Thanks David that did it.

I now have the plot down to almost exactly what i need. i have three more changes to make, or figure out how to work around.

can I:

1. change all of the colors of the contours to black? once before you posted that i should use [Color(-1,0,0,0)] to make all contours ...

after all of that, i think i found the problem, i need to delete docMaximize() from the cmds string don't I?


cheers
jerry

David,

i'm back at it agian, and now i am using your exapmle from btest2 to draw a plot into a form. i simply imported your example into my code and remmed my code, now i get the bitmap in the picture box but i also get Jr opening up and showing the plot at the same time.

maybe you can spot the ...

Thanks David,

I should be able to keep moving now.

i really appreciate your continued help on this project, though it is going slow being just a hobby i'm glad to be getting close.

cheers
jerry

David,

i solved part of the problem of finding the coordinates of the black pixels, but that brings up a new question. since my data needs to be interpreted in sequence by the device, i.e. it is reading a trail of bread crumbs, i need to know wether there may be "gaps" in the contour lines when ...

great,

i'll have to do some experimenting with sizes to find just the right size to give me 1 meter between pixels.

thanks
jerry

Jerry,
To get the same size 2D plot every time, regardless of whether there's a title or axis labels or not, use [Size(1,width in inches,height in inches,1)]. Width and height are the size of the box around the plot, not including axis labels, numbers, titles, etc.

wow, that's cool. if i make the ...

hi david,

i'm still plugging away at my project! i promise to send you a copy to try out, really. you may recall that i am working with GPS/Sonar data and making bathymetric charts with the goal of being able to upload the data back to the GPS unit. right now i have everything working except ...

thanks for the reply david,

the file size will no longer be a worry to me, though 6 million data points are not out of reality for me either!



as to repeated data: that's interesting that it takes only the highest value. i'll have to do some more research with some friend at NRAO and see if they ...

David,

don't know if you recall, but i am working with GPS/Sonar data to make contour plot for lake bottoms. you helped me with my app last fall and now all is working well and i am ready to go to the next step in the project.

right now i can open the gps/sonar units output file convert to lat ...