Image Zooming!

SDL Development
1

Hi there,
Can anyone let me know the method to Zoom an image ( Raw data image ) in
SDL. I will be zooming every frame and hence zooming must not reduce the
Frame rate very much.
If someone who has worked on this can explain to me about how it can be
done, it would be very helpful.
Thanks,
Raj

2

There’s a library that does it, check
http://www.ferzkopp.net/Software/SDL_gfx-2.0/. Can’t comment on performace
as I haven’t used it.

     Paulo

At 22:40 26/10/2002 -0400, you wrote:>Hi there,

Can anyone let me know the method to Zoom an image ( Raw data image ) in
SDL. I will be zooming every frame and hence zooming must not reduce the
Frame rate very much.
If someone who has worked on this can explain to me about how it can be
done, it would be very helpful.
Thanks,
Raj

<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
3

Messagethere is a library which does this, you may want to use it or check out the code for educational purposes…its called SDL_rotozoom which you can get from the SDL site…or by going here (this is the page linked to from the SDL site)

http://www.ferzkopp.net/Software/SDL_rotozoom/

im not sure how fast it is…but im betting its pretty well optomized so it is probably just about as fast as can be. Enjoy!----- Original Message -----
From: V.Rajashekar
To: sdl at libsdl.org
Sent: Saturday, October 26, 2002 7:40 PM
Subject: [SDL] Image Zooming !

Hi there,
Can anyone let me know the method to Zoom an image ( Raw data image ) in SDL. I will be zooming every frame and hence zooming must not reduce the Frame rate very much.
If someone who has worked on this can explain to me about how it can be done, it would be very helpful.
Thanks,
Raj

4

SDL_rotozoom is part of SDL_gfx. The speed is quite fast for a software
zooming, and you can use some nice antialiasing. However, it’s for
software surfaces only. If you need h/w, use OpenGL. There had been much
talking in the past about including some “glSDL_BlitResize” function in
David Olofson’s glSDL, but we haven’t seen anything yet. (for David: that
would be really important. are you working on it?)

Guido Imperiale

@CRUSADER_KY-------------------------------
CRV?ADER/KY
KnowledgE is PoweR