FillSolidRect & DrawText

Hey.

I recently ran into a problem trying to do some custom drawing in a view. (CScrollView derived). I use FillSolidRect to fill a rectangle, and then DrawText to render some text in OnDraw. The problem is that all of the text is set on the background that i set using FillSolidRect as opposed only to the bit that i defined as.
Here is some code:

Code:

---

pDC->FillSolidRect(        m_lbtnDown.x,
                                                m_lbtnDown.y,
                                                m_lbtnUp.x - m_lbtnDown.x,
                                                m_lbtnUp.y - m_lbtnDown.y,
                                                m_crTestA);
...
CPoint ScrolledPos = GetScrollPosition();
       
        CRect rectClient;
        GetClientRect(&rectClient);
       
        pOldFont        = pDC->SelectObject(m_pFont);
        nHeight                = MeasureFontHeight(m_pFont, pDC);
...
 pDC->DrawText(strRender, -1, &ScrollRect, DT_TOP|DT_NOPREFIX|DT_SINGLELINE);
...
pDC->SelectObject(pOldFont);

---

Any ideas why?

Thx in advance.

well it is hard to figure out what you are talking about, but I think you
should look up

CDC::IntersectClipRect

Ah, thx i will be looking into that.

Basically my problem is as follows (sry for crappy explanation b4, it was 4 am :D).

I need to draw a rectangle at some random x, y. I can draw that rectangle fine. Now i need to draw text overtop of it. When i start drawing text (using DrawText function), i use a loop that will effectively fill the whole screen from top to bottom. This also works fine by itself. Now when i try to do both, the rectangle and the text, for some reason the rectangle gets extended over all of the text. This is really weird, but i think it's something with me not clearing some buffer after i use FillSolidRect, and the DrawText function automatically uses that background for the text?

Is there something of that sort implemented within DrawText/FillSoliRect?

[EDIT]

I did some more debugging, and yep, it's something about the buffer. Basically if i reset the BgColor of the text after i draw the rectangle, the text will overwrite the rectangle with the color specified completely.

Is there a way to draw layers one after another, or will i have to calcualte the text offset that i want to be highlighted and then change the background for that piece of text?

Thx in advance.

Not sure I fully understand what you want, but I think you can use the same rect that you use for FillSolidRect and create a rectangular region (CreateRectRgn). Then, select that into your DC as a ClipRegion (SelectClipRgn). Now when you draw text (or anything else), your drawing will only occur within that region.

Be sure to select the NULL region to re-enable drawing in the entire DC.

Hope that helps.

Set the background mode to TRANSPARENT before drawing the text

Code:

---

        pDC->SetBkMode(TRANSPARENT);
        pDC->DrawText(strRender, -1, &ScrollRect, DT_TOP|DT_NOPREFIX|DT_SINGLELINE);

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Quote:

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Originally Posted by Quell

Hey.

I recently ran into a problem trying to do some custom drawing in a view. (CScrollView derived). I use FillSolidRect to fill a rectangle, and then DrawText to render some text in OnDraw. The problem is that all of the text is set on the background that i set using FillSolidRect as opposed only to the bit that i defined as.

Any ideas why?

Thx in advance.

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Yes, that is the normal behaviour.

After using FillSolidRect you have to call CDC::SetBkColor to (re-)set the background color for text outputting funtions. Another solution is to set the bk mode to TRANSPARENT (CDC:SetBkMode(TRANSPARENT) ) since you filled the background alredy ...

Hope this was useful.

With regards
Programartist
Ingo Bochmann