No text displayed using sdl_ttf

SDL Development
1

I’m trying to display a message on the screen with TTF_RenderText_Solid on windows xp.
I’m playing a video file using SDL and that works fine. I’m also drawing some lines on top
of the video and that works but I don’t see any text. I’m using sdl_ttf 2.0.8 and sdl 1.2.11.

I’ve checked all of the return values and everything looks ok, I think.
Can someone tell me what could be wrong or how to find out what isn’t working that causes no display?
Here is what I’m doing:

int flags, w, h;
SDL_Surface *screen;
SDL_Rect dest = { 50, 50, 200, 30 };

flags = SDL_HWSURFACE | SDL_ASYNCBLIT | SDL_HWACCEL | SDL_RESIZABLE;
w = 1200
h = 800

screen = SDL_SetVideoMode(w, h, 0, flags);

SDL_Color textColor = { 255, 0, 0 };
TTF_Font *fnt = TTF_OpenFont( “c:\windows\fonts\arial.ttf”, 20 );
strcpy(str, “Hello”);

message = TTF_RenderText_Solid(fnt, str, textColor);

int status = SDL_BlitSurface( message, NULL, screen, &dest );

// no error, but no text

thanks,
Bob

2

After SDL_BlitSurface() I added:

SDL_Flip(screen);

I neglected to list this line earlier:

SDL_DisplayYUVOverlay(vp->bmp, &rect);

After adding the SDL_Flip() line I now see the text, but it is blinking (or
tearing). How can I get a smooth text display?

BobOn Mon, Jul 16, 2007 at 02:35:46PM -0400, Bob Self wrote:

I’m trying to display a message on the screen with TTF_RenderText_Solid on windows xp.
I’m playing a video file using SDL and that works fine. I’m also drawing some lines on top
of the video and that works but I don’t see any text. I’m using sdl_ttf 2.0.8 and sdl 1.2.11.

I’ve checked all of the return values and everything looks ok, I think.
Can someone tell me what could be wrong or how to find out what isn’t working that causes no display?
Here is what I’m doing:

int flags, w, h;
SDL_Surface *screen;
SDL_Rect dest = { 50, 50, 200, 30 };

flags = SDL_HWSURFACE | SDL_ASYNCBLIT | SDL_HWACCEL | SDL_RESIZABLE;
w = 1200
h = 800

screen = SDL_SetVideoMode(w, h, 0, flags);

SDL_Color textColor = { 255, 0, 0 };
TTF_Font *fnt = TTF_OpenFont( “c:\windows\fonts\arial.ttf”, 20 );
strcpy(str, “Hello”);

message = TTF_RenderText_Solid(fnt, str, textColor);

int status = SDL_BlitSurface( message, NULL, screen, &dest );

3

Bob Self wrote:> On Mon, Jul 16, 2007 at 02:35:46PM -0400, Bob Self wrote:

I’m trying to display a message on the screen with TTF_RenderText_Solid on windows xp.
I’m playing a video file using SDL and that works fine. I’m also drawing some lines on top
of the video and that works but I don’t see any text. I’m using sdl_ttf 2.0.8 and sdl 1.2.11.

I’ve checked all of the return values and everything looks ok, I think.
Can someone tell me what could be wrong or how to find out what isn’t working that causes no display?
Here is what I’m doing:

int flags, w, h;
SDL_Surface *screen;
SDL_Rect dest = { 50, 50, 200, 30 };

flags = SDL_HWSURFACE | SDL_ASYNCBLIT | SDL_HWACCEL | SDL_RESIZABLE;
w = 1200
h = 800

screen = SDL_SetVideoMode(w, h, 0, flags);

SDL_Color textColor = { 255, 0, 0 };
TTF_Font *fnt = TTF_OpenFont( “c:\windows\fonts\arial.ttf”, 20 );
strcpy(str, “Hello”);

message = TTF_RenderText_Solid(fnt, str, textColor);

int status = SDL_BlitSurface( message, NULL, screen, &dest );

After SDL_BlitSurface() I added:

SDL_Flip(screen);

I neglected to list this line earlier:

SDL_DisplayYUVOverlay(vp->bmp, &rect);

After adding the SDL_Flip() line I now see the text, but it is blinking (or
tearing). How can I get a smooth text display?

Bob

I’m dealing with largely the same issue. I’ve tried using a secondary
SDL_Surface for the YUVOverlay, and blitting it on to the screen
SDL_Surface. This lets me draw my other surfaces over the video frame
without flicker, but it’s very slow and I end up dropping a lot of
frames in the process.

Does anyone know of a clean way to blit extra SDL_Surfaces to the
surface attached to a YUVOverlay before it updates?

4

Hello !

Are you using a YUV Overlay to play your video ?

CU

5

Yes, see my follow up post above.

BobOn Tue, Jul 17, 2007 at 02:24:28PM +0200, Torsten Giebl wrote:

Hello !

Are you using a YUV Overlay to play your video ?

CU

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6

Bob Self wrote:

flags = SDL_HWSURFACE | SDL_ASYNCBLIT | SDL_HWACCEL | SDL_RESIZABLE;

After SDL_BlitSurface() I added:

SDL_Flip(screen);

I neglected to list this line earlier:

SDL_DisplayYUVOverlay(vp->bmp, &rect);

After adding the SDL_Flip() line I now see the text, but it is blinking (or
tearing). How can I get a smooth text display?

Bob

I’ve noticed that with similar flags to yours, I don’t actually get a
hardware surface, according the flags in the SDL_Surface struct. Are you?