Array Containing Font Data for Rendering in OpenGL with stb_truetype

[rjopek]

Hi,

I'm working on a project where I use the stb_truetype library for rendering text in an OpenGL environment. I've encountered a problem related to different methods of loading font data. Here's a detailed description of the situation:

1. Actions Taken:

• I converted the "9x18.ttf" font to a C array using the command xxd -i 9x18.ttf > font_data.c.
• Then, I used the fontData array, which contains the data of "9x18.ttf" font, in my project.

2. Observed Problem:

• When loading the "9x18.ttf" font directly from the .ttf file, the text renders correctly.
• When I use the hard-coded fontData array with "9x18.ttf" data, the text does not display in the window.

3. Technical Details:

• I'm using the stbtt_InitFont and stbtt_BakeFontBitmap functions for font initialization and baking.
  Text rendering is done using stbtt_GetBakedQuad and standard OpenGL calls.

4. Questions:

• Can different methods of loading "9x18.ttf" font data affect rendering in OpenGL?
• Are there any known issues or limitations in the stb_truetype library that might explain this behavior?

5. Additional Information:

• I have checked that the first bytes of the font data are identical in both cases.
• I ensured that stbtt_InitFont returns success in both loading methods.
• I checked the OpenGL settings.

I would appreciate any suggestions or insights that might help me solve this problem.

[nothings]

There shouldn't be anything about stb_truetype (or OpenGL) that would cause this.

[rjopek]

Thank you for your response, Sean.

One thing I've noticed, which may or may not be relevant, is a slight difference in how the first bytes of the font data are printed out, depending on the method of loading:

• When using the array (fontData), the printout is: 00 01 00 00 00 0d 00 80 00 03
• When loading directly from the .ttf file, it shows as: 00010000000d00800003

I understand that this might simply be a formatting difference in the printout, but I wanted to mention it in case it provides any clues. The actual binary data appears to be the same in both cases. Do you think this could have any impact on how stb_truetype processes the font data?

[nothings]

i mean, it sounds like formatting, but what is doing the printing and why is it different? these seems very outside the scope of stb_truetype help, though, it sounds like you need help from a general C programming forum or something

[rjopek]

I fully understand that stb_truetype works directly with the binary data stored in arrays, and not with their textual representation as seen in the printout. The only reason I mentioned the difference in printout format was because it was the only discrepancy I could find during my troubleshooting process.

[rjopek]

I will continue to investigate other aspects of my implementation and settings that may affect the rendering of undisplayed text.