Creating a cursor from a surface

SDL Development
1

Can somebody give me a help with this? I want to load several cursors from
png files. Is there some way to convert pixel data into a cursor?–
Roger D. Vargas
ICQ: 117641572
Linux User: 180787

  • Much to learn you still have *
    Master Yoda, AOTC

–
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2

if you are using fullscreen mode, its suggested to use your own cursor, than you
can of course use any bitmap you want (maybe look at the archives)> ----- Original Message -----

From: roger@eht.scu.tur.cu (Roger D. Vargas)
To:
Sent: Thursday, July 10, 2003 11:28 PM
Subject: [SDL] creating a cursor from a surface

Can somebody give me a help with this? I want to load several cursors from
png files. Is there some way to convert pixel data into a cursor?

–
Roger D. Vargas
ICQ: 117641572
Linux User: 180787

  • Much to learn you still have *
    Master Yoda, AOTC

–
Este mensaje ha sido analizado por MailScanner
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3

you could disable the cursor and draw a surface at the mousecoordinates.> ----- Original Message -----

From: thomas.eder@nmi.at (Thomas Eder)
To:
Sent: Friday, July 11, 2003 9:53 AM
Subject: Re: [SDL] creating a cursor from a surface

if you are using fullscreen mode, its suggested to use your own cursor,
than you
can of course use any bitmap you want (maybe look at the archives)

----- Original Message -----
From: “Roger D. Vargas”
To:
Sent: Thursday, July 10, 2003 11:28 PM
Subject: [SDL] creating a cursor from a surface

Can somebody give me a help with this? I want to load several cursors
from
png files. Is there some way to convert pixel data into a cursor?

–
Roger D. Vargas
ICQ: 117641572
Linux User: 180787

  • Much to learn you still have *
    Master Yoda, AOTC

–
Este mensaje ha sido analizado por MailScanner
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4

Isn’t the bmp cursor method to much expansive in display terms ?
Doesn’t this requier to update Fullscreen on each mouvement ?

Carlos> ----- Original Message -----

From: fhufsky@phorus.at (Florian Hufsky)
To:
Sent: Friday, July 11, 2003 11:56 AM
Subject: Re: [SDL] creating a cursor from a surface

you could disable the cursor and draw a surface at the mousecoordinates.

----- Original Message -----
From: “Thomas Eder” <Thomas.Eder at nmi.at>
To:
Sent: Friday, July 11, 2003 9:53 AM
Subject: Re: [SDL] creating a cursor from a surface

if you are using fullscreen mode, its suggested to use your own cursor,
than you
can of course use any bitmap you want (maybe look at the archives)

----- Original Message -----
From: “Roger D. Vargas”
To:
Sent: Thursday, July 10, 2003 11:28 PM
Subject: [SDL] creating a cursor from a surface

Can somebody give me a help with this? I want to load several cursors
from
png files. Is there some way to convert pixel data into a cursor?

–
Roger D. Vargas
ICQ: 117641572
Linux User: 180787

  • Much to learn you still have *
    Master Yoda, AOTC

–
Este mensaje ha sido analizado por MailScanner
en busca de virus y otros contenidos peligrosos,
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5

maybe better do the reverse:
in your mainloop at each screen update print your mouse-bmp at the current mouse
position (hint: see docs for SDL_MOUSEMOTION, SDL_MouseMotionEvent),
if you have >30fps this should be sufficient.> ----- Original Message -----

From: citrouille@wanadoo.fr (Carlos Alvarez)
To:
Sent: Friday, July 11, 2003 12:09 PM
Subject: Re: [SDL] creating a cursor from a surface

Isn’t the bmp cursor method to much expansive in display terms ?
Doesn’t this requier to update Fullscreen on each mouvement ?

Carlos

----- Original Message -----
From: “Florian Hufsky”
To:
Sent: Friday, July 11, 2003 11:56 AM
Subject: Re: [SDL] creating a cursor from a surface

you could disable the cursor and draw a surface at the mousecoordinates.

----- Original Message -----
From: “Thomas Eder” <Thomas.Eder at nmi.at>
To:
Sent: Friday, July 11, 2003 9:53 AM
Subject: Re: [SDL] creating a cursor from a surface

if you are using fullscreen mode, its suggested to use your own cursor,
than you
can of course use any bitmap you want (maybe look at the archives)

----- Original Message -----
From: “Roger D. Vargas”
To:
Sent: Thursday, July 10, 2003 11:28 PM
Subject: [SDL] creating a cursor from a surface

Can somebody give me a help with this? I want to load several cursors
from
png files. Is there some way to convert pixel data into a cursor?

–
Roger D. Vargas
ICQ: 117641572
Linux User: 180787

  • Much to learn you still have *
    Master Yoda, AOTC

–
Este mensaje ha sido analizado por MailScanner
en busca de virus y otros contenidos peligrosos,
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http://www.libsdl.org/mailman/listinfo/sdl

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http://www.libsdl.org/mailman/listinfo/sdl

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SDL at libsdl.org
http://www.libsdl.org/mailman/listinfo/sdl

6

I posted the message bellow some time ago in response to this very same
question. It uses a function getpixel that does exactly that. Enjoy.

Andre de Leiradella
Yahoo | Mail, Weather, Search, Politics, News, Finance, Sports & Videos> ----- Original Message -----

From: @Andre_de_Leiradella (Andre de Leiradella)
To:
Sent: Thursday, April 10, 2003 4:48 PM
Subject: SDL_Surface → SDL_Cursor

That’s what I use to build a cursor from a surface (no dithering):

SDL_Cursor *SurfaceToCursor(SDL_Surface *image, int hx, int hy) {
int w, x, y;
Uint8 *data, *mask, *d, *m, r, g, b;
Uint32 color;
SDL_Cursor *cursor;

    w = (image->w + 7) / 8;
    data = (Uint8 *)alloca(w * image->h * 2);
    if (data == NULL)
            return NULL;
    memset(data, 0, w * image->h * 2);
    mask = data + w * image->h;
    if (SDL_MUSTLOCK(image))
            SDL_LockSurface(image);
    for (y = 0; y < image->h; y++) {
            d = data + y * w;
            m = mask + y * w;
            for (x = 0; x < image->w; x++) {
                    color = getpixel(image, x, y);
                    if ((image->flags & SDL_SRCCOLORKEY) == 0 || color

!= image->format->colorkey) {
SDL_GetRGB(color, image->format, &r, &g,
&b);
color = (r + g + b) / 3;
m[x / 8] |= 128 >> (x & 7);
if (color < 128)
d[x / 8] |= 128 >> (x & 7);
}
}
}
if (SDL_MUSTLOCK(image))
SDL_UnlockSurface(image);
cursor = SDL_CreateCursor(data, mask, w, image->h, hx, hy);
return cursor;
}

Andre de Leiradella
Yahoo | Mail, Weather, Search, Politics, News, Finance, Sports & Videos

7

No, you only have to update previous & actual mouse area :wink:
It can be done really fast

Pirata

Isn't the bmp cursor method to much expansive in display terms ?
Doesn't this requier to update Fullscreen on each mouvement ?

CarlosOn Fri, 2003-07-11 at 07:09, Carlos wrote:

----- Original Message -----
From: "Florian Hufsky" <fhufsky at phorus.at>
To: <sdl at libsdl.org>
Sent: Friday, July 11, 2003 11:56 AM
Subject: Re: [SDL] creating a cursor from a surface


> you could disable the cursor and draw a surface at the mousecoordinates.
>
> ----- Original Message -----
> From: "Thomas Eder" <Thomas.Eder at nmi.at>
> To: <sdl at libsdl.org>
> Sent: Friday, July 11, 2003 9:53 AM
> Subject: Re: [SDL] creating a cursor from a surface
>
>
> >
> > if  you are using fullscreen mode, its suggested to use your own cursor,
> than you
> > can of course use any bitmap you want (maybe look at the archives)
> >
> > ----- Original Message -----
> > From: "Roger D. Vargas" <roger at eht.scu.tur.cu>
> > To: <SDL at libsdl.org>
> > Sent: Thursday, July 10, 2003 11:28 PM
> > Subject: [SDL] creating a cursor from a surface
> >
> >
> > >
> > > Can somebody give me a help with this? I want to load several cursors
> from
> > > png files. Is there some way to convert pixel data into a  cursor?
> > >
> > >
> > > --
> > > Roger D. Vargas
> > > ICQ: 117641572
> > > Linux User: 180787
> > > * Much to learn you still have *
> > > Master Yoda, AOTC
> > >
> > >
> > > --
> > > Este mensaje ha sido analizado por MailScanner
> > > en busca de virus y otros contenidos peligrosos,
> > > y se considera que est? limpio.
> > >
> > >
> > > _______________________________________________
> > > SDL mailing list
> > > SDL at libsdl.org
> > > http://www.libsdl.org/mailman/listinfo/sdl
> >
> >
> >
> > _______________________________________________
> > SDL mailing list
> > SDL at libsdl.org
> > http://www.libsdl.org/mailman/listinfo/sdl
> >
> >
>
>
>
> _______________________________________________
> SDL mailing list
> SDL at libsdl.org
> http://www.libsdl.org/mailman/listinfo/sdl
>


_______________________________________________
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8

I posted the message bellow some time ago in response to this very same
question. It uses a function getpixel that does exactly that. Enjoy.

Andre de Leiradella
Yahoo | Mail, Weather, Search, Politics, News, Finance, Sports & Videos
thanks a lot.On Fri, 11 Jul 2003, Andre de Leiradella wrote:

----- Original Message -----
From: Andre de Leiradella
To:
Sent: Thursday, April 10, 2003 4:48 PM
Subject: SDL_Surface → SDL_Cursor

That’s what I use to build a cursor from a surface (no dithering):

SDL_Cursor *SurfaceToCursor(SDL_Surface *image, int hx, int hy) {
int w, x, y;
Uint8 *data, *mask, *d, *m, r, g, b;
Uint32 color;
SDL_Cursor *cursor;

    w = (image->w + 7) / 8;
    data = (Uint8 *)alloca(w * image->h * 2);
    if (data == NULL)
            return NULL;
    memset(data, 0, w * image->h * 2);
    mask = data + w * image->h;
    if (SDL_MUSTLOCK(image))
            SDL_LockSurface(image);
    for (y = 0; y < image->h; y++) {
            d = data + y * w;
            m = mask + y * w;
            for (x = 0; x < image->w; x++) {
                    color = getpixel(image, x, y);
                    if ((image->flags & SDL_SRCCOLORKEY) == 0 || color

!= image->format->colorkey) {
SDL_GetRGB(color, image->format, &r, &g,
&b);
color = (r + g + b) / 3;
m[x / 8] |= 128 >> (x & 7);
if (color < 128)
d[x / 8] |= 128 >> (x & 7);
}
}
}
if (SDL_MUSTLOCK(image))
SDL_UnlockSurface(image);
cursor = SDL_CreateCursor(data, mask, w, image->h, hx, hy);
return cursor;
}

Andre de Leiradella
Yahoo | Mail, Weather, Search, Politics, News, Finance, Sports & Videos

SDL mailing list
SDL at libsdl.org
http://www.libsdl.org/mailman/listinfo/sdl

–
Roger D. Vargas
ICQ: 117641572
Linux User: 180787

  • Much to learn you still have *
    Master Yoda, AOTC

–
Este mensaje ha sido analizado por MailScanner
en busca de virus y otros contenidos peligrosos,
y se considera que est? limpio.