/**
* Copyright © 2014 Mattias Andrée (maandree@member.fsf.org)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <stdio.h>
#include <inttypes.h>
#include <X11/Xlib.h>
#include <X11/extensions/xf86vmode.h>
/**
* The X server display
*/
static Display* display;
/**
* The X screen
*/
static int screen;
/**
* Size of colour curves on the X-axis
*/
static int curve_size;
/**
* Start stage of colour curve control
*
* @param use_screen The screen to use
* @return Zero on success
*/
int blueshift_vidmode_open(int use_screen)
{
int _major, _minor;
uint16_t* r_gamma;
uint16_t* g_gamma;
uint16_t* b_gamma;
/* Get X display */
if ((display = XOpenDisplay(NULL)) == NULL)
{
fprintf(stderr, "Cannot open X display\n");
return 1;
}
/* Check for VidMode extension */
if (XF86VidModeQueryVersion(display, &_major, &_minor) == 0)
{
fprintf(stderr, "VidMode version query failed\n");
XCloseDisplay(display);
return 1;
}
/* Get curve X-axis size */
screen = use_screen;
if (XF86VidModeGetGammaRampSize(display, screen, &curve_size) == 0)
{
fprintf(stderr, "VidMode gamma size query failed\n");
XCloseDisplay(display);
return 1;
}
if (curve_size < 1)
{
fprintf(stderr, "VidMode gamma size query failed\n");
XCloseDisplay(display);
return 1;
}
/* Acquire curve control */
r_gamma = malloc(3 * curve_size * sizeof(uint16_t));
if (r_gamma == NULL)
{
fprintf(stderr, "Out of memory\n");
return 1;
}
g_gamma = r_gamma + curve_size;
b_gamma = g_gamma + curve_size;
if (XF86VidModeGetGammaRamp(display, screen, curve_size, r_gamma, g_gamma, b_gamma) == 0)
{
fprintf(stderr, "VidMode gamma query failed\n");
free(r_gamma);
XCloseDisplay(display);
return 1;
}
free(r_gamma);
return 0;
}
/**
* Gets the current colour curves
*
* @param use_crtc The CRTC to use
* @return {the size of the red curve, *the red curve,
* the size of the green curve, *the green curve,
* the size of the blue curve, *the blue curve}, needs to be free:d
*/
uint16_t* blueshift_vidmode_read(int use_crtc)
{
(void) use_crtc;
/* Read curves */
uint16_t* r_gamma = ((uint16_t*)malloc((3 + 3 * curve_size) * sizeof(uint16_t))) + 1;
uint16_t* g_gamma = r_gamma + curve_size + 1;
uint16_t* b_gamma = g_gamma + curve_size + 1;
if (r_gamma == NULL)
{
fprintf(stderr, "Out of memory\n");
XCloseDisplay(display);
return NULL;
}
if (XF86VidModeGetGammaRamp(display, screen, curve_size, r_gamma, g_gamma, b_gamma) == 0)
{
fprintf(stderr, "VidMode gamma query failed\n");
free(r_gamma);
XCloseDisplay(display);
return NULL;
}
*(r_gamma - 1) = curve_size;
*(g_gamma - 1) = curve_size;
*(b_gamma - 1) = curve_size;
return r_gamma;
}
/**
* Apply stage of colour curve control
*
* @param use_crtcs Mask of CRTC:s to use
* @param r_curve The red colour curve
* @param g_curve The green colour curve
* @param b_curve The blue colour curve
* @return Zero on success
*/
int blueshift_vidmode_apply(uint64_t use_crtcs, uint16_t* r_curve, uint16_t* g_curve, uint16_t* b_curve)
{
(void) use_crtcs;
/* Apply curves */
if (XF86VidModeSetGammaRamp(display, screen, curve_size, r_curve, g_curve, b_curve) == 0)
{
fprintf(stderr, "VidMode gamma control failed\n");
return 1;
}
return 0;
}
/**
* Resource freeing stage of colour curve control
*/
void blueshift_vidmode_close(void)
{
/* Free remaining resources */
XCloseDisplay(display);
}
