view test/testcursor.c @ 4216:5b99971a27b4 SDL-1.2

Fixed bug #698 Hans de Goede 2009-02-13 01:10:52 PST Since the new "glitch free" version of pulseaudio (used in Fedora 10 amongst others), the sound of SDL using apps (like a simple playmus call) has been crackling. While looking in to fixing this I noticed that the current pulseaudio code in SDL uses pa_simple. However pa_simple uses a thread to pump pulseaudio events and ipc, given that SDL already has its own thread for audio handling this is clearly suboptimal, leading to unnecessary context switching IPC, etc. Also pa_simple does not allow one to implement the WaitAudio() callback for SDL audiodrivers properly. Given that my work is mostly a rewrite (although some original pieces remain) I'm attaching the new .c and .h file, as that is easier to review then the huge diff. Let me know if you also want the diff. This new version has the following features: -no longer use an additional thread next to the SDL sound thread -do not crackle with glitch free audio -when used with a newer pulse, which does glitch free audio, the total latency is the same as with the alsa driver -proper WaitAudio() implementation, saving another mixlen worth of latency -adds a WaitDone() implementation This patch has been written in consultancy with Lennart Poetering (the pulseaudio author) and has been reviewed by him for correct use of the pa API.
author Sam Lantinga <slouken@libsdl.org>
date Mon, 21 Sep 2009 09:27:08 +0000
parents e7d2858670c1
children
line wrap: on
line source

#include <stdio.h>
#include <stdlib.h>

#include "SDL.h"

/* This is an example 16x16 cursor
	top left :	black
	top right : inverted color or black
	bottom left: white
	bottom right: transparent
	(swap left and right for different endianness)
*/

Uint16 cursor_data[16]={
	0xffff,
	0xffff,
	0xffff,
	0xffff,	

	0xffff,
	0xffff,
	0xffff,
	0xffff,	

	0x0000,
	0x0000,
	0x0000,
	0x0000,

	0x0000,
	0x0000,
	0x0000,
	0x0000
};

Uint16 cursor_mask[16]={
	0xff00,
	0xff00,
	0xff00,
	0xff00,

	0xff00,
	0xff00,
	0xff00,
	0xff00,

	0xff00,
	0xff00,
	0xff00,
	0xff00,

	0xff00,
	0xff00,
	0xff00,
	0xff00
};

/* another test cursor: smaller than 16x16, and with an odd height */

Uint8 small_cursor_data[11] = { 0x00, 0x18, 0x08, 0x38, 0x44, 0x54, 0x44, 0x38, 0x20, 0x20, 0x00 };
Uint8 small_cursor_mask[11] = { 0x3C, 0x3C, 0x3C, 0x7C, 0xC6, 0xC6, 0xC6, 0x7C, 0x78, 0x70, 0x70 };

/* 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 *create_arrow_cursor()
{
  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 (arrow[4+row][col]) {
        case 'X':
          data[i] |= 0x01;
          mask[i] |= 0x01;
          break;
        case '.':
          mask[i] |= 0x01;
          break;
        case ' ':
          break;
      }
    }
  }
  sscanf(arrow[4+row], "%d,%d", &hot_x, &hot_y);
  return SDL_CreateCursor(data, mask, 32, 32, hot_x, hot_y);
}


int main(int argc, char *argv[])
{
	SDL_Surface *screen;
	SDL_bool quit = SDL_FALSE, first_time = SDL_TRUE;
	SDL_Cursor *cursor[3];
	int current;

	/* Load the SDL library */
	if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) {
		fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
		return(1);
	}

	screen = SDL_SetVideoMode(320,200,8,SDL_ANYFORMAT);
	if (screen==NULL) {
		fprintf(stderr, "Couldn't initialize video mode: %s\n",SDL_GetError());
		return(1);
	}

	SDL_FillRect(screen, NULL, 0x664422);

	cursor[0] = SDL_CreateCursor((Uint8 *)cursor_data, (Uint8 *)cursor_mask,
		16, 16, 8, 8);
	if (cursor[0]==NULL) {
		fprintf(stderr, "Couldn't initialize test cursor: %s\n",SDL_GetError());
		SDL_Quit();
		return(1);
	}
	cursor[1] = create_arrow_cursor();
	if (cursor[1]==NULL) {
		fprintf(stderr, "Couldn't initialize arrow cursor: %s\n",SDL_GetError());
		SDL_FreeCursor(cursor[0]);
		SDL_Quit();
		return(1);
	}
	cursor[2] = SDL_CreateCursor(small_cursor_data, small_cursor_mask,
		8, 11, 3, 5);
	if (cursor[2]==NULL) {
		fprintf(stderr, "Couldn't initialize test cursor: %s\n",SDL_GetError());
		SDL_Quit();
		return(1);
	}

	current = 0;
	SDL_SetCursor(cursor[current]);

	while (!quit) {
		SDL_Event	event;
		while (SDL_PollEvent(&event)) {
			switch(event.type) {
				case SDL_MOUSEBUTTONDOWN:
					current = (current + 1)%3;
					SDL_SetCursor(cursor[current]);
					break;
				case SDL_KEYDOWN:
					if (event.key.keysym.sym == SDLK_ESCAPE) {
						quit = SDL_TRUE;
					}
					break;
				case SDL_QUIT:
					quit = SDL_TRUE;
					break;
			}
		}	
		SDL_Flip(screen);
		SDL_Delay(1);
	}

	SDL_FreeCursor(cursor[0]);
	SDL_FreeCursor(cursor[1]);
	SDL_FreeCursor(cursor[2]);

	SDL_Quit();
	return(0);
}