/**
* 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 <xcb/xcb.h>
#include <xcb/randr.h>
/**
* The major version of RANDR the program expects
*/
#define RANDR_VERSION_MAJOR 1U
/**
* The minor version of RANDR the program expects
*/
#define RANDR_VERSION_MINOR 3U
/**
* Data structure for CRTC caches
*/
typedef struct blueshift_randr_crtc
{
/**
* Size of colour curves on the X-axis
*/
unsigned int curve_size;
/**
* This entity holds the allocation to the colour curves
*/
xcb_randr_get_crtc_gamma_reply_t* gamma_get_reply;
/**
* Red colour curve
*/
uint16_t* r_curve;
/**
* Green colour curve
*/
uint16_t* g_curve;
/**
* Blue colour curve
*/
uint16_t* b_curve;
/**
* CRT controller
*/
xcb_randr_crtc_t* crtc;
} blueshift_randr_crtc_t;
/**
* Connection to the X server
*/
static xcb_connection_t* connection;
/**
* Used to store errors in
*/
static xcb_generic_error_t* error;
/**
* Screen resources
*/
static xcb_randr_get_screen_resources_current_reply_t* res_reply;
/**
* The first CRTC
*/
static blueshift_randr_crtc_t* crtcs;
/**
* The CRTC after the last CRTC
*/
static blueshift_randr_crtc_t* crtcs_end;
/**
* Start stage of colour curve control
*
* @return Zero on success
*/
int blueshift_randr_open(void)
{
blueshift_randr_crtc_t* crtcs_;
xcb_randr_query_version_cookie_t version_cookie;
xcb_randr_query_version_reply_t* randr_version;
const xcb_setup_t* setup;
xcb_screen_iterator_t iter;
xcb_screen_t* screen;
xcb_randr_get_screen_resources_current_cookie_t res_cookie;
unsigned int crtc_count;
xcb_randr_get_crtc_gamma_size_cookie_t gamma_size_cookie;
xcb_randr_get_crtc_gamma_size_reply_t* gamma_size_reply;
xcb_randr_get_crtc_gamma_cookie_t gamma_get_cookie;
/* Get X connection */
connection = xcb_connect(NULL, NULL /* preferred screen */);
/* Check RANDR protocol version */
version_cookie = xcb_randr_query_version(connection, RANDR_VERSION_MAJOR, RANDR_VERSION_MINOR);
randr_version = xcb_randr_query_version_reply(connection, version_cookie, &error);
if (error || (randr_version == NULL))
{
fprintf(stderr, "RANDR version query returned %i", error ? error->error_code : -1);
xcb_disconnect(connection);
return 1;
}
if (randr_version->major_version != RANDR_VERSION_MAJOR || randr_version->minor_version < RANDR_VERSION_MINOR)
{
fprintf(stderr, "Unsupported RANDR version, got %u.%u, expected %u.%u\n",
randr_version->major_version, randr_version->minor_version,
RANDR_VERSION_MAJOR, RANDR_VERSION_MINOR);
free(randr_version);
xcb_disconnect(connection);
return 1;
}
free(randr_version);
/* Get X resources */
setup = xcb_get_setup(connection);
iter = xcb_setup_roots_iterator(setup);
screen = iter.data;
res_cookie = xcb_randr_get_screen_resources_current(connection, screen->root);
res_reply = xcb_randr_get_screen_resources_current_reply(connection, res_cookie, &error);
if (error)
{
fprintf(stderr, "RANDR screen resource query returned %i\n", error->error_code);
xcb_disconnect(connection);
return 1;
}
/* Get CRTC:s */
crtc_count = res_reply->num_crtcs;
crtcs = malloc(crtc_count * sizeof(blueshift_randr_crtc_t));
crtcs->crtc = xcb_randr_get_screen_resources_current_crtcs(res_reply);
crtcs_end = crtcs + crtc_count;
/* Prepare CRTC:s */
for (crtcs_ = crtcs; crtcs_ != crtcs_end; crtcs_++)
{
/* Set CRTC */
if (crtcs_ != crtcs)
crtcs_->crtc = (crtcs_ - 1)->crtc + 1;
/* Get curve X-axis size */
gamma_size_cookie = xcb_randr_get_crtc_gamma_size(connection, *(crtcs_->crtc));
gamma_size_reply = xcb_randr_get_crtc_gamma_size_reply(connection, gamma_size_cookie, &error);
if (error)
{
fprintf(stderr, "RANDR CRTC gamma size query returned %i\n", error->error_code);
xcb_disconnect(connection);
return 1;
}
crtcs_->curve_size = gamma_size_reply->size;
free(gamma_size_reply);
/* Acquire curve control */
gamma_get_cookie = xcb_randr_get_crtc_gamma(connection, *(crtcs_->crtc));
crtcs_->gamma_get_reply = xcb_randr_get_crtc_gamma_reply(connection, gamma_get_cookie, &error);
if (error)
{
fprintf(stderr, "RANDR CRTC gamma query returned %i\n", error->error_code);
xcb_disconnect(connection);
return 1;
}
crtcs_->r_curve = xcb_randr_get_crtc_gamma_red(crtcs_->gamma_get_reply);
crtcs_->g_curve = xcb_randr_get_crtc_gamma_green(crtcs_->gamma_get_reply);
crtcs_->b_curve = xcb_randr_get_crtc_gamma_blue(crtcs_->gamma_get_reply);
}
return 0;
}
/**
* 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_randr_apply(uint64_t use_crtcs, uint16_t* r_curve, uint16_t* g_curve, uint16_t* b_curve)
{
blueshift_randr_crtc_t* crtcs_ = crtcs;
unsigned int i;
xcb_void_cookie_t gamma_set_cookie;
/* Use CRTC:s */
while (crtcs_ != crtcs_end)
{
/* Check whether we should use the CRTC */
if ((use_crtcs & 1) == 0)
goto next_crtc;
/* Set curves */
for (i = 0; i < crtcs_->curve_size; i++)
{
*(crtcs_->r_curve + i) = *(r_curve + i);
*(crtcs_->g_curve + i) = *(g_curve + i);
*(crtcs_->b_curve + i) = *(b_curve + i);
}
/* Apply curves */
gamma_set_cookie = xcb_randr_set_crtc_gamma_checked(connection, *(crtcs_->crtc), crtcs_->curve_size,
crtcs_->r_curve, crtcs_->g_curve, crtcs_->b_curve);
error = xcb_request_check(connection, gamma_set_cookie);
if (error)
{
fprintf(stderr, "RANDR CRTC control returned %i\n", error->error_code);
return 1;
}
/* Next CRTC */
next_crtc:
crtcs_++;
use_crtcs >>= 1;
}
return 0;
}
/**
* Resource freeing stage of colour curve control
*/
void blueshift_randr_close(void)
{
blueshift_randr_crtc_t* crtcs_;
/* Free CRTC resources */
for (crtcs_ = crtcs; crtcs_ != crtcs_end; crtcs_++)
free(crtcs_->gamma_get_reply);
/* Free remaining resources */
free(crtcs);
free(res_reply);
xcb_disconnect(connection);
}
int main(int argc, char** argv)
{
uint16_t* r_curve = malloc(3 * 256 * sizeof(uint16_t));
uint16_t* g_curve = r_curve + 256;
uint16_t* b_curve = g_curve + 256;
long i;
(void) argc;
(void) argv;
if (blueshift_randr_open())
{
free(r_curve);
return 1;
}
for (i = 0; i < 256; i++)
r_curve[i] = g_curve[i] = b_curve[i] = (int)((float)i / 255.f * (float)((1 << 16) - 1) + 0.f);
if (blueshift_randr_apply(~0, r_curve, g_curve, b_curve))
{
free(r_curve);
return 1;
}
blueshift_randr_close();
free(r_curve);
return 0;
}
