Numerical Recipes in BASIC and WIMP

Hi all,

I recently start to “seriously” learn how to program in BASIC for the WIMP. I chose the book “Numerical Recipes in C” as a common thread (http://numerical.recipes). This is a nice and concrete subject.
I open this thread as a central place to post questions and issues I will encounter during this journey.

You can find the application (called !NuRecipes) in its current state at
http://www.riscos.ovh/public/nurecipes.zip

See you very soon.

François

Hi again.

Let start with a first issue.
In the main menu (iconbar menu), when you navigate to “Preliminaries.Phase of the moon”, a dialog box opens where you can input data. But when you click on the action button to open the popupmenu to select the desired phase, WIMP closes the main menu and the dialogue box, leavinng only the “Moon phases” menu open.
How can I keep the main menu and the dialog box open?

Thank you for your help.

François

If you’re using the Toolbox then you should enable the “local” flag in ResEd. If you’re not using the Toolbox then I defer to an expert :)

Nope… I do not use the ToolBox. But just had a quick look at the manual… and I think I should use it :)

Regards

I think you want to be using Wimp_CreateSubMenu to open that menu rather than Wimp_CreateMenu, but it’s not something I’ve tried before, so I could be wrong. I suspect there’s a few other nicities which need to be adjusted to take this into account too.

Yes, normally you’d use Wimp_CreateSubMenu to prevent the current menu from being closed, whether it works in this case I’m not sure. The dialogue is opened as part of the menu and windows are officially only allowed as leaf items.

If Wimp_CreateSubMenu doesn’t work then the dialogue box would need to be opened as a regular, ie non-transient, window. The pop-up menu can then be created using Wimp_CreateMenu.

How can I keep the main menu and the dialog box open?

If a dialogue is more complicated than a simple click, shouldn’t it be opened on its own and not as part of a menu structure? That way the user can set up what needs set up and then click OK or something to “make it so”.

Hi,

I think that indeed, when a dialog box gets more complicated, it makes sense to open it on its own. I tried usin Wimp_CreateSubMenu but then this generates an internal data transfer error when using Wimp_DecodeMenu to response to a Wimp-Poll reason code 9.
So, definitly, dialog box should be restricted to be leaf node and not kind of submenu.

Thank you for your help.

François

Sorry, I’d misunderstood and my previous post is wrong. Setting “local” won’t help in this case (at least I presume it won’t; I haven’t actually tried this particular case).

Hi,

I am rewriting !NuRecipes in order to use the Toolbox. I have to admit this reduce considerably the amount of code required and make structuring the application easier.
So far, I have a question: in a writable field (or any gadget displaying text), how can I get the max length allowed for the text buffer. This is important to truncate (using LEFT$) the string to the max length when calling the method “WritableField_SetValue” and avoid crashing the application.

Without the toolbox, I was using “Wimp_GetIconState” to read R1!36. I can’t find the equivalent in the toolbox.

Thank you for your help.

François

I’m sure I must have done that sort of thing before, but I can’t figure out how I did it. However, I’m currently at work so I don’t have access to my copy of the Toolbox manual, which I’ve written all over :)

I suppose in the meantime you could use Gadget_GetIconList to get the Wimp icon number, which you could then feed into Wimp_GetIconState, but there is almost certainly a way of doing this without needing to call Wimp SWIs directly.

The method “WritableField_GetValue” with R4 = 0 returns the size of the buffer in R5.
Same for ActionButton_GetText, Button_GetValue, DisplayField_GetValue, Draggable_GetText, OptionButton_GetLabel, RadioButton_GetLabel, ScrollList_GetItemText, and TextArea_GetText.
But not for Label or LabelledBox, for those you’ll need to get the Wimp icon number.
I think StringSet_GetSelected will also return the size of buffer in R5 if R4 = 0 although that’s not specified in the StrongHelp manual.
And for ToolAction_GetIdent I think you need to check that the ToolAction has text and not a sprite.

Hi

Unfortunately, “WritableField_GetValue” and alike with R4=0 returns the lenght of the text currently stored (+1 for the termination character) , not the max buffer length allowed as specified in !ResEd.
I just wrote a routine to do it and will upload the “Toolbox” version of !NuRecipes soon.

DEF FNread_size(win_id%,gadget_id%)
  REM returns the max length of the buffer size
LOCAL size%,icon_list%,icon_list_ptr%,wimp_hdl%,c%,found%
  REM Get size of buffer required to hold icon list
  SYS "Toolbox_ObjectMiscOp",0,win_id%,68,gadget_id%,0 TO ,,,,,size%
  icon_list%=FNclaim(size%)

REM Get icon list
SYS “Toolbox_ObjectMiscOp”,0,win_id%,68,gadget_id%,icon_list%,size%
icon_list_ptr%=icon_list%
REM Get Wimp window handle
SYS “Toolbox_ObjectMiscOp”,0,win_id%,0 TO wimp_hdl%
REM Loop through the list looking for the icon containing text
c%=FNclaim(40)
!c%=wimp_hdl%:found%=FALSE
WHILE NOT found% AND (icon_list_ptr%-icon_list% < size%)
c%!4 = !icon_list_ptr%
SYS “Wimp_GetIconState”,,c%
REM check if icon contains text
IF (c%!24 AND &1)=1 THEN
REM icon contains text
size%=c%!36
found%=TRUE
ENDIF
icon_list_ptr%+=4
ENDWHILE
PROCrelease(c%)
PROCrelease(icon_list%)
=size%

Regards

François

Hello

I wonder what error code range can be used for application specific errors. In the Reference Manual, it is mentioned

Errors produced by BASIC are in the range 0 to 127.

Thank you

François

https://www.riscosopen.org/content/allocate

in a writable field (or any gadget displaying text), how can I get the max length allowed for the text buffer?

I suppose in the meantime you could use Gadget_GetIconList to get the Wimp icon number, which you could then feed into Wimp_GetIconState, but there is almost certainly a way of doing this without needing to call Wimp SWIs directly.

It is a bit late – I have been away on holiday – but there is a way to get the buffer length from the object data without going to the Wimp.

DEFFN_GINFO(object%,gadget%) REM get gadget info
 SYS"Toolbox_GetTemplateName",,object%,END,255
 SYS"Toolbox_TemplateLookUp",,END TO !END
 SYS"Window_ExtractGadgetInfo",,!END,gadget% TO !END
=!END

This returns a pointer to the gadget info block. The first 36 bytes are a standard header for all gadgets, followed by the gadget-specific info. You can find the template for each type in the manual.

For a writable field this is:

text              4 MsgReference
max_text_len      4 word
allowable         4 MsgReference
max_allowable_len 4 word
before            4 word
after             4 word

So the max length allowed for the text buffer is:

!(FN_GINFO(object%,gadget%)+40)

Some points:

The use of END above, to avoid creating local variables, might upset some, but it is legal and works. ;-)

I feel that the buffer length ought to be an attribute of itself, or at least discoverable more easily.

I do no know of an easier way to get the object template than through the name, but I would be delighted to be shown one.

The equivalent for buffers in non-window objects is:

DEFFN_OINFO(object%) REM REM get object ino
 SYS"Toolbox_GetTemplateName",,object%,END,255
 SYS"Toolbox_TemplateLookUp",,END TO !END
=!END

The common header is also 36 bytes.

Why/how is ProgInfo.Version writable, but not buffered?