demos do not handle NK_UINT_DRAW_INDEX flag, resulting in broken rendering

Xeverous — Yesterday at 8:38 PM
I have found an issue where defining NK_UINT_DRAW_INDEX completely destroys the rendering, I see shaded rectangles, no UI or any text. Happens with SDL backend. Will try to reproduce on pure C and minimal code.
I confirm. This is completely broken. Add -DNK_UINT_DRAW_INDEX to demo/sdl_opengl2/Makefile and see yourself.

sleeptightAnsiC — 12:40 PM
This is probably also broken with most other demos. Only two demos (d3d11 and d3d12) have a condition related to this flag. I suspect you could take a look at how d3d11 solves it, and try applying the same. https://github.com/Immediate-Mode-UI/Nuklear/blob/9afb3dd6d14fba0c5e62f08809b494b6d580b9b1/demo/d3d11/nuklear_d3d11.h#L89-L93

sleeptightAnsiC — 12:44 PM
Does this patch fixes the issue for you?
[see patch below]
^ This should work. I just tested it on my side.

diff --git a/demo/sdl_opengl2/nuklear_sdl_gl2.h b/demo/sdl_opengl2/nuklear_sdl_gl2.h
index 18509f1..f9a0144 100644
--- a/demo/sdl_opengl2/nuklear_sdl_gl2.h
+++ b/demo/sdl_opengl2/nuklear_sdl_gl2.h
@@ -158,7 +158,11 @@ nk_sdl_render(enum nk_anti_aliasing AA)
                 (GLint)((height - (GLint)(cmd->clip_rect.y + cmd->clip_rect.h)) * scale.y),
                 (GLint)(cmd->clip_rect.w * scale.x),
                 (GLint)(cmd->clip_rect.h * scale.y));
+        #ifdef NK_UINT_DRAW_INDEX
+            glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_INT, offset);
+        #else
             glDrawElements(GL_TRIANGLES, (GLsizei)cmd->elem_count, GL_UNSIGNED_SHORT, offset);
+        #endif
             offset += cmd->elem_count;
         }
         nk_clear(&sdl.ctx);