Difference in WM_PAINT messages ?

[dedndave]

in your WM_PAINT code, you use EBX and EDI without preserving them   :P

[dedndave]

something screwy with the text loop

to test it, i jumped around it - and the screen is black again   :P

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jmp around

mov edx,[FirstLine]
__NextLine:
mov eax,edx
mov ecx,[BytesPerLine]
mov ebx,eax
shl ebx,7
push edx
mul [LineHeight]
pop edx
;mov edx,[CurrentLine]
add ebx,[pmem]
push edx
invoke ExtTextOut, memdc,3,eax,ETO_OPAQUE or ETO_NUMERICSLATIN,addr rect,ebx,[ecx+4*edx],NULL
pop edx
inc edx
mov eax,[LastLine]
cmp eax,edx
jns __NextLine

around:

[gelatine1]

I changed the GetOutlineTextMetrics function to this

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mov outtxt.otmSize,SIZEOF OUTLINETEXTMETRIC
invoke GetOutlineTextMetrics,hdc,SIZEOF OUTLINETEXTMETRIC,offset outtxt


nothing changed

I preserved ebx and edi like this:

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cmp eax,WM_PAINT
jnz __cont0
push ebx
push edi

...

pop edi
pop ebx


Nothing changed :( I'm kinda lost in all this

And okay  :t I'll find what's going wrong in the text loop

[gelatine1]

This ETO_OPAQUE flag in the ExtTextOut function messed everything up.
I have a black background again  But... this happens:



i set the text to red so it doesn't get hidden in the backgrounds :p

What is this ? another flag that should be altered ? or um oh right I need to use SetBkgndColor to black I guess ?

EDIT: SetBkColor did the thing :) although there is still something wrong with the LineHeight now. Can't seem to get it right

[dedndave]

even though you filled in the bitmap with all black, you still have to set the background color for ExtTextOut

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invoke  SetBkColor,memdc,0

http://msdn.microsoft.com/en-us/library/dd162713%28v=vs.85%29.aspx

The ExtTextOut function draws text using the currently selected font, background color,
and text color. You can optionally provide dimensions to be used for clipping, opaquing, or both.

[dedndave]

the line height thing is probably a clipping issue
to test that theory, try it without clipping

but, i think your clipping rectangle isn't moving with your text

[gelatine1]

May I ask , what is clipping? Do you know any article about it ?

Thanks in advance, I hope I'm not bothering you too much

[dedndave]

well - clipping is like "not drawing outside this rectangle"
for example - your text is wider than the area you want to display it - you clip it
in this case, you are not using clipping - you don't have that flag set in ExtTextOut
so - you don't really need a rectangle pointer, either (also used for opaquing)

but - that's not where the problem lies
the problem lies here, with the calculation of the top of the rect for InvalidateRect   

Code Select Expand

mov ecx,[CurrentLine]
shl ecx,7
mov edx,[pmem]
add edx,ecx

mov ecx,[CurrentLine]
mov ebx,[BytesPerLine]
mov ebx,[ebx+4*ecx]

mov [edx+ebx],eax

inc ebx
mov edx,[BytesPerLine]
mov [edx+4*ecx],ebx

mov rect.left,0
shl ecx,4
mov rect.top,ecx
mov rect.right,4FFh
add ecx,16
mov rect.bottom,ecx
invoke InvalidateRect,hWnd,offset rect,0

[dedndave]

you can test it very easily....

type 4 lines of text - notice that each line is shorter   :P

now, minimize the window - then restore it
this causes the OS to send a WM_PAINT message with the entire client area as the update region

[dedndave]

you have to use the LineHeight variable in that calculation   :t

[dedndave]

try this one.....

[gelatine1]

Thanks a lot once again dave. You have been really helpful so thank you for all of that :) I finally got everything working well again.

[Tedd]

A few suggestions..

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mov dword ptr [esi+4],CS_HREDRAW or CS_VREDRAW
This can actually be zeroed -- these flags cause the WHOLE window to be redrawn every time the size changes, which will result in flicker.

Using the BLACK_BRUSH for the window background is perfectly fine, flicker is caused by the background being cleared unnecessarily. Specifically, when you call InvalidateRect, the last parameter is true/false to say whether you want the background cleared in the invalidated rectangle; setting it to false means it won't be cleared, which is fine as long as you're drawing entirely over the area so no previous pixels remain - which you are, with BitBlt.

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invoke GlobalAlloc,GHND,65535
mov hmem,eax
invoke GlobalLock,hmem
mov pmem,eax
can simply be:

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invoke GlobalAlloc,GPTR,65535
mov pmem,eax

and to free:

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invoke GlobalFree,pmem
Equally for BytesPerLine.
There's no need to lock/unlock, it's a left-over from windows 3.