view docs/man3/SDL_CreateCursor.3 @ 689:5bb080d35049

Date: Tue, 19 Aug 2003 17:57:00 +0200 From: Stephane Marchesin Subject: Re: [SDL] [patch] MMX alpha blit patches with MMX detection I think everything is correct now. I've done as much testing as I could, but some real-world testing wouldn't hurt, I think. The patch is here : http://icps.u-strasbg.fr/~marchesin/sdl_mmxblit.patch If you do byte-by-byte comparison of the output between C and MMX functions, you'll notice that the results for 555 and 565 RGB alpha blits aren't exactly the same. This is because MMX functions for 555 and 565 RGB have an higher accuracy. If you want the exact same behaviour that's possible by masking the three lower alpha bits in the MMX functions. Just ask ! I removed one MMX function because after I fixed it to match its C equivalent, it revealed to be slower than the C version on a PIII (although a bit faster on an Athlon XP). I've also added MMX and PIII replacements for SDL_memcpy. Those provide some speed up in testvidinfo -benchmark (at least for me, under linux & X11).
author Sam Lantinga <slouken@libsdl.org>
date Fri, 22 Aug 2003 05:51:19 +0000
parents e5bc29de3f0a
children 546f7c1eb755
line wrap: on
line source

.TH "SDL_CreateCursor" "3" "Tue 11 Sep 2001, 23:01" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_CreateCursor\- Creates a new mouse cursor\&.
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBSDL_Cursor *\fBSDL_CreateCursor\fP\fR(\fBUint8 *data, Uint8 *mask, int w, int h, int hot_x, int hot_y\fR);
.SH "DESCRIPTION"
.PP
Create a cursor using the specified \fBdata\fR and \fBmask\fR (in MSB format)\&. The cursor width must be a multiple of 8 bits\&.
.PP
The cursor is created in black and white according to the following: 
.TP 20
\fBData / Mask\fR
\fBResulting pixel on screen\fR
.TP 20
0 / 1
White
.TP 20
1 / 1
Black
.TP 20
0 / 0
Transparent
.TP 20
1 / 0
Inverted color if possible, black if not\&.
.PP
Cursors created with this function must be freed with \fISDL_FreeCursor\fR\&.
.SH "EXAMPLE"
.PP
.nf
\f(CW/* Stolen from the mailing list */
/* Creates a new mouse cursor from an XPM */


/* XPM */
static const char *arrow[] = {
  /* width height num_colors chars_per_pixel */
  "    32    32        3            1",
  /* colors */
  "X c #000000",
  "\&. c #ffffff",
  "  c None",
  /* pixels */
  "X                               ",
  "XX                              ",
  "X\&.X                             ",
  "X\&.\&.X                            ",
  "X\&.\&.\&.X                           ",
  "X\&.\&.\&.\&.X                          ",
  "X\&.\&.\&.\&.\&.X                         ",
  "X\&.\&.\&.\&.\&.\&.X                        ",
  "X\&.\&.\&.\&.\&.\&.\&.X                       ",
  "X\&.\&.\&.\&.\&.\&.\&.\&.X                      ",
  "X\&.\&.\&.\&.\&.XXXXX                     ",
  "X\&.\&.X\&.\&.X                         ",
  "X\&.X X\&.\&.X                        ",
  "XX  X\&.\&.X                        ",
  "X    X\&.\&.X                       ",
  "     X\&.\&.X                       ",
  "      X\&.\&.X                      ",
  "      X\&.\&.X                      ",
  "       XX                       ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "                                ",
  "0,0"
};

static SDL_Cursor *init_system_cursor(const char *image[])
{
  int i, row, col;
  Uint8 data[4*32];
  Uint8 mask[4*32];
  int hot_x, hot_y;

  i = -1;
  for ( row=0; row<32; ++row ) {
    for ( col=0; col<32; ++col ) {
      if ( col % 8 ) {
        data[i] <<= 1;
        mask[i] <<= 1;
      } else {
        ++i;
        data[i] = mask[i] = 0;
      }
      switch (image[4+row][col]) {
        case \&'X\&':
          data[i] |= 0x01;
          k[i] |= 0x01;
          break;
        case \&'\&.\&':
          mask[i] |= 0x01;
          break;
        case \&' \&':
          break;
      }
    }
  }
  sscanf(image[4+row], "%d,%d", &hot_x, &hot_y);
  return SDL_CreateCursor(data, mask, 32, 32, hot_x, hot_y);
}\fR
.fi
.PP
.SH "SEE ALSO"
.PP
\fI\fBSDL_FreeCursor\fP\fR, \fI\fBSDL_SetCursor\fP\fR, \fI\fBSDL_ShowCursor\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:01