1. Final: code (using Win32lib) that doesnt seem to work proper.
- Posted by euman at bellsouth.net
May 30, 2002
----- Original Message -----
From: "Derek Parnell" <Derek.Parnell at SYD.RABOBANK.COM>
> G'day,
> nice to hear from you again.
Thanks for responding so quickly.
> The reason you would be having trouble is that there are two DC's involved
> in the example code.
I finally broke down and looked into this in the library.
> The one you get, and the one that drawEllipse() uses.
> They are NOT the same one. In Win32lib, each of the wrapped graphics
> routines, gets its own DC and releases it again before returning to the
> caller. The one exception is if all the draw routines are called inside a
> Paint event. In that case, all share the same DC until the paint event
> completes.
This would be a problem for graphic objects and slow the library down
not to mention bloat the library with repeat code.
If you were to use "OwnDC" then a Window DC would be allocated
for the life of the Window and no other DC would be required, unless
you were using a Double buffering method ofcourse.
> Hope that helps. I'm currently rewriting the DC handling inside the library.
> One of the things you will be able to do is get a DC and then use that DC
> with the wrapped graphics routines until you decide to release it. I mostly
> got that working except for Pixmap and Bitmaps, so I should probably finish
> it this weekend.
You answered my reply above and this is a good thing for the library.
for example, there are some API's that arent wrapped yet that would require
a DC handle and we dont really need to obtain a handle, use it then destroy
each time we use a particular object. "one will do just fine"
Thanks Big-D I attached some more of that demo program for everyone to look at
(below) I think its a neat demo and has lots of potential written all over it.
P.S Derek look at the pInitExtent, I can use this "InitExtent =
getClientRect(MainWin)"
to obtain my client coords but must poke them if I need to use pointers.
Is there already a routine for this?
P.P.S if you need any help with pixmaps and Bitmaps I could probably help out in
that area now. Im still working on my Installers but I need a small break before
I
go insane.
> ----------
> Derek.
Euman
-- Similar but not a copy of Chapter 10 - Windows 2000 Graphics API Black Book
(Coriolis & Damon Chandler))
-- Highly recommended Book for the Serious Windows API Programmers.
-- Euman 2002
without warning
include Win32Lib.ew
constant
xSetViewportExtEx = registerw32Function(gdi32, "SetViewportExtEx",
{C_LONG,C_INT,C_INT,C_INT},C_INT)
,xSetWindowExtEx = registerw32Function(gdi32,
"SetWindowExtEx",{C_LONG,C_INT,C_INT,C_POINTER},C_INT)
,iEllipse = registerw32Procedure(gdi32,
"Ellipse",{C_LONG,C_INT,C_INT,C_INT,C_INT})
,iDrawText = registerw32Procedure(user32,
"DrawTextA",{C_LONG,C_POINTER,C_INT,C_POINTER,C_UINT})
object junk
constant
MainWin = create( Window, "Mapping Mode Scaling Demo", NULL, 25, 25, 300, 200,
0 )
sequence InitExtent
atom MainWinDC, hFont, oldMapMode, pInitExtent, pText
constant
MM_ANISOTROPIC = 8
-- onOpen_MainWin
procedure onOpen_MainWin( integer self, integer event, sequence parms )
sequence Text
InitExtent = getClientRect( MainWin )
pInitExtent = allocate(16)
poke4(pInitExtent , InitExtent[1])
poke4(pInitExtent+4 , InitExtent[2])
poke4(pInitExtent+8 , InitExtent[3])
poke4(pInitExtent+12, InitExtent[4])
MainWinDC = getDC ( MainWin )
hFont = EzCreateFont(MainWin, MainWinDC,"Times New Roman",120,0,0,1,0)
junk=w32Func(xSelectObject,{MainWinDC,hFont})
oldMapMode = w32Func(xSetMapMode,{MainWinDC,MM_ANISOTROPIC})
Text = "Euman's Win32lib Demo's"
pText = allocate_string(Text)
if w32Func(xSetGraphicsMode,{MainWinDC, GM_ADVANCED}) then
end if
end procedure
setHandler(MainWin, w32HOpen, routine_id("onOpen_MainWin"))
-- onResize_MainWin
procedure onResize_MainWin( integer self, integer event, object parms )
sequence CurExtent
CurExtent = getClientRect( MainWin )
setPenColor( MainWin, White )
repaintRect( MainWin, CurExtent[1], CurExtent[2], CurExtent[3], CurExtent[4])
if
w32Func(xSetWindowExtEx,{MainWinDC,InitExtent[3]-InitExtent[1],InitExtent[4]-InitExtent[2],0})
then
if
w32Func(xSetViewportExtEx,{MainWinDC,CurExtent[3]-CurExtent[1],CurExtent[4]-CurExtent[2],0})
then
w32Proc(iEllipse,{MainWinDC, InitExtent[1], InitExtent[2], InitExtent[3],
InitExtent[4]})
w32Proc(iDrawText,{MainWinDC, pText, -1, pInitExtent, or_all({DT_CENTER,
DT_VCENTER, DT_SINGLELINE})})
end if
end if
end procedure
setHandler(MainWin, w32HResize, routine_id("onResize_MainWin"))
-- onPaint_MainWin
procedure onPaint_MainWin( integer self, integer event, sequence parms )
object junk
junk = w32Func( xInvalidateRect, {MainWin, NULL, 1} )
end procedure
setHandler(MainWin, w32HPaint, routine_id("onPaint_MainWin"))
-- onFocus_MainWin
procedure onFocus_MainWin( integer self, integer event, sequence parms )
onResize_MainWin( 0,0,0)
end procedure
setHandler(MainWin, w32HGotFocus, routine_id("onFocus_MainWin"))
-- onClose_MainWin
procedure onClose_MainWin( integer self, integer event, sequence parms )
free(pText)
free(pInitExtent)
releaseDC ( MainWin )
end procedure
setHandler(MainWin, w32HClose, routine_id("onClose_MainWin"))
WinMain( MainWin, Normal )
