Hello Everybody,
Could anyone please tell me how to get ssh to work without asking for passwords? (i want to do a ssh <hostname> without getting a request for a password but getting connected straight away)
I have attempted the following but to no avail :( ...
I tried to generate a SSH... (5 Replies)
So basically what im trying to do is ...
Open file, read that file, than try to find ..
We or we and replace them with I, but not replace the cases where words contain We or we, such as Went, went, etc
a and replace them with the, but not replace the cases where words contain a, such as... (1 Reply)
One of our servers runs Solaris 8 and does not have "ls -lh" as a valid command. I wrote the following script to make the ls output easier to read and emulate "ls -lh" functionality. The script works, but it is slow when executed on a directory that contains a large number of files. Can anyone make... (10 Replies)
Hey all my co-workers and I are trying to put together a list of things root "Can't" do on any *NIX OS, so I wanted to come here and see what all we could come up with.
Here are two to start this off:
write to a read only mount FS
kill a tape rewind
Please add what you know.
Thanks,... (5 Replies)
Can someone help me edit the below script to make it run faster?
Shell: bash
OS: Linux Red Hat
The point of the script is to grab entire chunks of information that concerns the service "MEMORY_CHECK".
For each chunk, the beginning starts with "service {", and ends with "}".
I should... (15 Replies)
Hi,
I have a large number of input files with two columns of numbers.
For example:
83 1453
99 3255
99 8482
99 7372
83 175
I only wish to retain lines where the numbers fullfil two requirements. E.g:
=83
1000<=<=2000
To do this I use the following... (10 Replies)
SDL_PixelFormat(3) SDL API Reference SDL_PixelFormat(3)NAME
SDL_PixelFormat - Stores surface format information
STRUCTURE DEFINITION
typedef struct SDL_PixelFormat {
SDL_Palette *palette;
Uint8 BitsPerPixel;
Uint8 BytesPerPixel;
Uint8 Rloss, Gloss, Bloss, Aloss;
Uint8 Rshift, Gshift, Bshift, Ashift;
Uint32 Rmask, Gmask, Bmask, Amask;
Uint32 colorkey;
Uint8 alpha;
} SDL_PixelFormat;
STRUCTURE DATA
palette Pointer to the palette, or NULL if the BitsPerPixel>8
BitsPerPixel The number of bits used to represent each pixel in a surface. Usually 8, 16, 24 or 32.
BytesPerPixel The number of bytes used to represent each pixel in a surface. Usually one to four.
[RGBA]mask Binary mask used to retrieve individual color values
[RGBA]loss Precision loss of each color component (2^[RGBA]loss)
[RGBA]shift Binary left shift of each color component in the pixel value
colorkey Pixel value of transparent pixels
alpha Overall surface alpha value
DESCRIPTION
A SDL_PixelFormat describes the format of the pixel data stored at the pixels field of a SDL_Surface. Every surface stores a SDL_PixelFor-
mat in the format field.
If you wish to do pixel level modifications on a surface, then understanding how SDL stores its color information is essential.
8-bit pixel formats are the easiest to understand. Since its an 8-bit format, we have 8 BitsPerPixel and 1 BytesPerPixel. Since BytesPer-
Pixel is 1, all pixels are represented by a Uint8 which contains an index into palette->colors. So, to determine the color of a pixel in a
8-bit surface: we read the color index from surface->pixels and we use that index to read the SDL_Color structure from surface->for-
mat->palette->colors. Like so:
SDL_Surface *surface;
SDL_PixelFormat *fmt;
SDL_Color *color;
Uint8 index;
.
.
/* Create surface */
.
.
fmt=surface->format;
/* Check the bitdepth of the surface */
if(fmt->BitsPerPixel!=8){
fprintf(stderr, "Not an 8-bit surface.
");
return(-1);
}
/* Lock the surface */
SDL_LockSurface(surface);
/* Get the topleft pixel */
index=*(Uint8 *)surface->pixels;
color=fmt->palette->colors[index];
/* Unlock the surface */
SDL_UnlockSurface(surface);
printf("Pixel Color-> Red: %d, Green: %d, Blue: %d. Index: %d
",
color->r, color->g, color->b, index);
.
.
Pixel formats above 8-bit are an entirely different experience. They are considered to be "TrueColor" formats and the color information is
stored in the pixels themselves, not in a palette. The mask, shift and loss fields tell us how the color information is encoded. The mask
fields allow us to isolate each color component, the shift fields tell us the number of bits to the right of each component in the pixel
value and the loss fields tell us the number of bits lost from each component when packing 8-bit color component in a pixel.
/* Extracting color components from a 32-bit color value */
SDL_PixelFormat *fmt;
SDL_Surface *surface;
Uint32 temp, pixel;
Uint8 red, green, blue, alpha;
.
.
.
fmt=surface->format;
SDL_LockSurface(surface);
pixel=*((Uint32*)surface->pixels);
SDL_UnlockSurface(surface);
/* Get Red component */
temp=pixel&fmt->Rmask; /* Isolate red component */
temp=temp>>fmt->Rshift;/* Shift it down to 8-bit */
temp=temp<<fmt->Rloss; /* Expand to a full 8-bit number */
red=(Uint8)temp;
/* Get Green component */
temp=pixel&fmt->Gmask; /* Isolate green component */
temp=temp>>fmt->Gshift;/* Shift it down to 8-bit */
temp=temp<<fmt->Gloss; /* Expand to a full 8-bit number */
green=(Uint8)temp;
/* Get Blue component */
temp=pixel&fmt->Bmask; /* Isolate blue component */
temp=temp>>fmt->Bshift;/* Shift it down to 8-bit */
temp=temp<<fmt->Bloss; /* Expand to a full 8-bit number */
blue=(Uint8)temp;
/* Get Alpha component */
temp=pixel&fmt->Amask; /* Isolate alpha component */
temp=temp>>fmt->Ashift;/* Shift it down to 8-bit */
temp=temp<<fmt->Aloss; /* Expand to a full 8-bit number */
alpha=(Uint8)temp;
printf("Pixel Color -> R: %d, G: %d, B: %d, A: %d
", red, green, blue, alpha);
.
.
.
SEE ALSO
SDL_Surface, SDL_MapRGB
SDL Tue 11 Sep 2001, 23:01 SDL_PixelFormat(3)