Build fails on recent macOS (with Xcode 15):

  src/drawgl.c:215:3: error: call to undeclared function 'gluBuild2DMipmaps'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
                  gluBuild2DMipmaps(GL_TEXTURE_2D, GL_ALPHA, gmap->xsz, gmap->ysz, GL_ALPHA, GL_UNSIGNED_BYTE, gmap->pixels);
                  ^
  1 error generated.
  make: *** [src/drawgl.o] Error 1

I think it is missing the right header?

Hello!

I'm having problems with the compilation process. How should I install freetype so that it is possible to compile libdrawtext? I am using visual studio 2017.

Kind regards

does this library support OpenGL ES?

specifically Android GLESv3 (OpenGL ES 3.2 with EGL 1.4)

Even after make install, ubuntu can not find the libdrawtext.so.0 file. I was able to fix this with the command: sudo cp libdrawtext/ libdrawtext.so.0 /usr/lib

I suggest that glBlendFunc be removed from the GL backend, I came across a case where I had to use my own blending function, I found this to be a bit limiting.

(Yes, I can edit the source, and that's what I did, but it's still worthy to discuss).

It seems like if I hand-edited the comment header of the .glyphmap file I could selectively delete specific glyphs from the range, such as those not available in that particular font. But I'd also need to go delete the pixels or I'd reduce the utilisation of the texture memory.

Say in this case I just wanted the arrows. I could exact each pair as a range, and then write a script to combine them back into a new .glyphmap file?

Do you feel like this is a job for libdrawtext or something wrapped on top of it?

I'm interested in using libdrawtext with pre-cooked glyphmap files, perhaps gzipped.

I noticed in the implementation that P6 PPM RGB mode is being used, but that P5 PGM greyscale could be used to reduce the file size. Seems like dtx_load_glyphmap_stream could be extended to support P5 for input.

-rw-r--r--   1 nigels  staff   1.0M 25 Jun 20:15 linux-biolinum_s96_r0020-007f.glyphmap
-rw-r--r--   1 nigels  staff    48K 25 Jun 20:15 linux-biolinum_s96_r0020-007f.pgm.gz
-rw-r--r--   1 nigels  staff    82K 25 Jun 19:58 linux-biolinum_s96_r0020-007f.ppm.gz

Okay so, in my project I changed the glOrtho like so (it's a must):

   glOrtho(-x/2, x/2, -y/2, y/2, -1, 1); // from
   glOrtho(0, x, y, 0, 0, 1); // to

And as expected, the text is now flipped and upside down. No matter what I do; I can't seem to get the text to flip/rotate. I have rotated textures in the past with OpenGL, but for some reason my methods will not work with dtx_string.

• Thanks, I am only classifying this as an issue because I am capable of rotating everything else properly, but not the text.

Hello, I learned from the source code that there are 0-255 character sets, and there is no way to support Chinese.

I can't figure out how to use shaders with this library. I would like to have an example...

The Intel integrated graphics card cannot display fonts

make -C tools/font2glyphmap fails with clang compiler (on macOS) because:

clang -pedantic -Wall -g -I../../src   -c -o src/font2glyphmap.o src/font2glyphmap.c
clang -o font2glyphmap src/font2glyphmap.o -L../.. -Wl,-rpath=../.. -ldrawtext
ld: unknown option: -rpath=../..

-Wl,-rpath=../.. is not a valid option, it should be -Wl,-rpath,../..

How to support Chinese？

Just wanted to let you know that currently the baseline doesn't seem to be saved to or loaded from the glyphmap file.

Hello. When I compile unicode example (commented out cjk stuff) I get the following result:

Russian characters are drawing corrupted except for the last word.

But when make only one call to dtx_prepare_range like so:
dtx_prepare_range(fntmain, FONT_SZ, 0, 0x500); /* cyrilic */
(from zero to 0x500)
then russian characters are drawing as expected: