hackthelobby/libcaca/examples/gamma.c

125 lines
4.0 KiB
C

/*
* gamma libcaca gamma test program
* Copyright (c) 2006-2012 Sam Hocevar <sam@hocevar.net>
* All Rights Reserved
*
* This program is free software. It comes without any warranty, to
* the extent permitted by applicable law. You can redistribute it
* and/or modify it under the terms of the Do What the Fuck You Want
* to Public License, Version 2, as published by Sam Hocevar. See
* http://www.wtfpl.net/ for more details.
*/
#include "config.h"
#if !defined(__KERNEL__)
# include <stdio.h>
# include <math.h>
#endif
#include "caca.h"
uint32_t buffer[256 * 4];
int main(int argc, char *argv[])
{
caca_event_t ev;
caca_canvas_t *cv, *cw, *mask;
caca_display_t *dp;
caca_dither_t *left, *right;
float gam;
int x;
cv = caca_create_canvas(0, 0);
if(cv == NULL)
{
printf("Can't created canvas\n");
return -1;
}
dp = caca_create_display(cv);
if(dp == NULL)
{
printf("Can't create display\n");
return -1;
}
cw = caca_create_canvas(caca_get_canvas_width(cv), caca_get_canvas_height(cv));
mask = caca_create_canvas(caca_get_canvas_width(cv), caca_get_canvas_height(cv));
for(x = 0; x < 256; x++)
{
buffer[x] = (x << 16) | (x << 8) | (x<< 0);
buffer[x + 256] = (0xff << 16) | (x << 8) | (0x00 << 0);
buffer[x + 512] = (0x00 << 16) | (0xff << 8) | (x << 0);
buffer[x + 768] = (x << 16) | (0x00 << 8) | (0xff << 0);
}
left = caca_create_dither(32, 256, 4, 4 * 256,
0x00ff0000, 0x0000ff00, 0x000000ff, 0x0);
right = caca_create_dither(32, 256, 4, 4 * 256,
0x00ff0000, 0x0000ff00, 0x000000ff, 0x0);
gam = caca_get_dither_gamma(right);
caca_set_display_time(dp, 20000);
for(x = 0; ; x++)
{
int ret = caca_get_event(dp, CACA_EVENT_KEY_PRESS, &ev, 0);
if(ret)
{
if(caca_get_event_key_ch(&ev) == CACA_KEY_LEFT)
gam /= 1.03;
else if(caca_get_event_key_ch(&ev) == CACA_KEY_RIGHT)
gam *= 1.03;
else if(caca_get_event_key_ch(&ev) == CACA_KEY_DOWN)
gam = 1.0;
else if(caca_get_event_key_ch(&ev) == CACA_KEY_ESCAPE)
break;
}
/* Resize the spare canvas, just in case the main one changed */
caca_set_canvas_size(cw, caca_get_canvas_width(cv), caca_get_canvas_height(cv));
caca_set_canvas_size(mask, caca_get_canvas_width(cv), caca_get_canvas_height(cv));
/* Draw the regular dither on the main canvas */
caca_dither_bitmap(cv, 0, 0, caca_get_canvas_width(cv),
caca_get_canvas_height(cv), left, buffer);
/* Draw the gamma-modified dither on the spare canvas */
caca_set_dither_gamma(right, gam);
caca_dither_bitmap(cw, 0, 0, caca_get_canvas_width(cw),
caca_get_canvas_height(cw), right, buffer);
/* Draw something on the mask */
caca_set_color_ansi(mask, CACA_LIGHTGRAY, CACA_BLACK);
caca_clear_canvas(mask);
caca_set_color_ansi(mask, CACA_WHITE, CACA_WHITE);
caca_fill_ellipse(mask, (1.0 + sin(0.05 * (float)x))
* 0.5 * caca_get_canvas_width(mask),
(1.0 + cos(0.05 * (float)x))
* 0.5 * caca_get_canvas_height(mask),
caca_get_canvas_width(mask) / 2,
caca_get_canvas_height(mask) / 2, '#');
/* Blit the spare canvas onto the first one */
caca_blit(cv, 0, 0, cw, mask);
caca_set_color_ansi(cv, CACA_WHITE, CACA_BLUE);
caca_printf(cv, 2, 1,
"gamma=%g - use arrows to change, Esc to quit", gam);
caca_refresh_display(dp);
}
caca_free_dither(left);
caca_free_dither(right);
caca_free_display(dp);
caca_free_canvas(mask);
caca_free_canvas(cw);
caca_free_canvas(cv);
return 0;
}