Weird rendering in 64-bit build only under OS X 10.9

SDL Development
1

Hello,

I’m using SDL2 in the framework of a small cross-platform tool to render a webcam preview. In OS X (my test platform is a vmware’s VM with OS X 10.9 Mavericks – no choice, I don’t have any real Mac at hand currently), it works well with a 32-bit build (ie. i386), but not with the 64-bit (aka. x86_64) one: the first frame is displayed with large diagonale streaks in the half right/bottom part (triangle) and following frames are simply ignored.

I’m using the SDL_LockTexture/SDL_UnlockTexture way to update the texture when a new frame arrives from the camera. I made an attempt with renderer created with SDL_RENDERER_ACCELERATED and SDL_RENDERER_SOFTWARE flags: no change!

I first tried with an SDL2 coming from homebrew, then I uninstalled this version and I built the current release (SDL2-2.0.8.tar.gz) as Fat/Universal (32 + 64-bit) by myself… Same result! I also tried against shared and static libs (ie. libSDL2.a and libSDL2main.a) and it doesn’t change the result.

So, does it’s an issue because of OS X in a VM (but, then, why it well works with a 32-bit build) or a known issue about SDL2 in OS X? What do you think?

2

Well, I reduced to a minimal test code (here, loading a BMP file to get ride of all the webcam stuff, but keeping the way I display it – through texture).

#include <sdl2/sdl.h>

int main()
{
  int w = 512; int h = 512;

  SDL_Init(SDL_INIT_VIDEO);

  SDL_Window* wnd = SDL_CreateWindow("Preview", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, w, h, 0);
  SDL_Renderer* renderer = SDL_CreateRenderer(wnd, -1, SDL_RENDERER_ACCELERATED);
  SDL_Surface* surface = SDL_LoadBMP("test.bmp");
  SDL_Texture* texture = SDL_CreateTextureFromSurface(renderer, surface);
  SDL_RenderCopy(renderer, texture, NULL, NULL);
  SDL_RenderPresent(renderer);

  getchar(); /* just to see the result */

  SDL_DestroyTexture(texture);
  SDL_FreeSurface(surface);
  SDL_DestroyRenderer(renderer);
  SDL_DestroyWindow(wnd);
  SDL_Quit();
  return 0;
}

Here are the results (when built in 32-bit at left side, and in 64-bit at right side):

snap_0005416-both
snap_0005416-both.jpg800×420 56 KB

Here, how I built them:
clang -arch i386 test.c -L/usr/local/lib -lsdl2 -o test32
clang -arch x86_64 test.c -L/usr/local/lib -lsdl2 -o test64

EDIT: OK, it only does this with OS X 10.9 Mavericks. Tried in others VMs with 10.10 Yosemite and 10.12 Sierra and it’s all OK. In another VM with 10.9 Mavericks, it does the same; so it’s not something specificaly broken in a single VM with OS X 10.9. Also, I noticed it (the culprit 64-bit build) works one time after a fresh reboot, then all following calls fail as show in the right-side image above. It would be interesting to know if this issue appears in a real Mac with OS X 10.9 Mavericks…

3

It looks like this should work. Can you report a bug on http://bugzilla.libsdl.org and include the source above, along with test.bmp so we can try to reproduce it?

Thanks!

4

No problem to report it in your bug tracker, but at this time Bugzilla seems to fail to send me the confirmation email (and nothing in spam folder, of course).

5

Can you post a link to your test image, in the meantime?

Thanks!

6

Yep, here it is : http://eeweb.poly.edu/~yao/EL5123/image/lena_gray.bmp

7

Hello, renewed my registration on bugzilla.libsdl.org and never received any confirmation email. So, maybe you should take a look in your logs to see if nothing goes wrong (maybe because my email address contains a “dot” in the username part or blacklister domain, don’t know)… Well, just so you know.