Jump to content
  • Advertisement
Sign in to follow this  
athreoz

ID3DXFont::DrawTextA using DT_CALCRECT calculates imprecise values

This topic is 2173 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

Hey GD community,

I'm experiencing problems when calculating the on-screen width of a string using the [font=courier new,courier,monospace]DrawTextA[/font] method of the [font=courier new,courier,monospace]ID3DXFont[/font] DirectX9 interface with the [font=courier new,courier,monospace]DT_CALCRECT[/font] parameter. Whenever I use a different font than Arial, the values returned in the [font=courier new,courier,monospace]RECT[/font] structure become imprecise what makes it impossible for me to correctly draw a caret in my edit-box implementation (when not using Arial as font).
I already tried to solve this problem by calculating the width using the [font=courier new,courier,monospace]GetTextExtentPoint32A[/font] GDI API or even by calling [font=courier new,courier,monospace]GetCharABCWidthsFloatA[/font] and summing up A, B and C for every single character (when initialzing the font) and then manually adding the widths of the single characters together for the whole string - without success. None of the calculated values are precise.
The code I'm using to load the font:


const std::string &rFontName = std::string("Calibri");
unsigned height = 16;
// ...
ID3DXFont *pD3DFont = nullptr;
if (FAILED(D3DXCreateFontA(m_pDevice,
height, 0,
FW_NORMAL,
1, false,
DEFAULT_CHARSET,
OUT_DEFAULT_PRECIS,
PROOF_QUALITY,
DEFAULT_PITCH | FF_DONTCARE,
rFontName.c_str(),
&pD3DFont)))
{
throw NXGFWError("Could not initialize font");
}


And the method I use to determine the on-screen width:


uint D3D9RenderEngine::calcTextWidth(const std::string &rText,
uint fontHeight,
const std::string &rFontName)
{
// Grab font
const sFont &rFont = _retriveFont(rFontName, fontHeight);
// Calculate
SIZE s;
GetTextExtentPoint32A(rFont.pFont->GetDC(),
rText.c_str(),
rText.length(),
&s);
return (uint)s.cx;
} // ==> calcTextWidth


My question is if this is a bug in the [font=courier new,courier,monospace]ID3DXFont[/font] interface or if I'm doing something wrong - I googled the whole day without finding a suitable solution. You guys are my last hope! :)

Thanks in advance!

Greetings,
athreoz

Share this post


Link to post
Share on other sites
Advertisement
Anyone? I guess I'll have to write my own font class in case noone is capable of providing an answer. :/

Share this post


Link to post
Share on other sites
Sign in to follow this  

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

Participate in the game development conversation and more when you create an account on GameDev.net!

Sign me up!