/**
* libgamma -- Display server abstraction layer for gamma ramp adjustments
* Copyright (C) 2014, 2015 Mattias Andrée (maandree@member.fsf.org)
*
* This library is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef HAVE_LIBGAMMA_METHOD_W32_GDI
# error Compiling gamma-w32-gdi.c without HAVE_LIBGAMMA_METHOD_W32_GDI
#endif
#include "gamma-w32-gdi.h"
#include "libgamma-error.h"
#ifndef WINVER
# define WINVER 0x0500
#endif
#ifdef FAKE_LIBGAMMA_METHOD_W32_GDI
# include "fake-w32-gdi.h"
#else
# include <windows.h>
# include <wingdi.h>
#endif
#include <errno.h>
/**
* The gamma ramp size that devices will always have in Windows GDI.
*
* @see http://msdn.microsoft.com/en-us/library/windows/desktop/dd372194(v=vs.85).aspx
*/
#define GAMMA_RAMP_SIZE 256
/**
* Return the capabilities of the adjustment method.
*
* @param this The data structure to fill with the method's capabilities.
*/
void libgamma_w32_gdi_method_capabilities(libgamma_method_capabilities_t* restrict this)
{
/* Gamma ramps size, depth and support can be queried. */
this->crtc_information = LIBGAMMA_CRTC_INFO_GAMMA_SIZE
| LIBGAMMA_CRTC_INFO_GAMMA_DEPTH;
/* Windows GDI does not support sites or partitions. */
this->default_site_known = 1;
this->multiple_sites = 0;
this->multiple_partitions = 0;
/* Windows GDI does support CRTC:s. */
this->multiple_crtcs = 1;
/* Partitions are not support... */
this->partitions_are_graphics_cards = 0;
/* Windows GDI does not have system restore capabilities. */
this->site_restore = 0;
this->partition_restore = 0;
this->crtc_restore = 0;
/* Ramps sizes are fixed and identical and ramp depth is too. */
this->identical_gamma_sizes = 1;
this->fixed_gamma_size = 1;
this->fixed_gamma_depth = 1;
/* Windows GDI is a real adjustment method that can be faked. */
#ifdef FAKE_LIBGAMMA_METHOD_W32_GDI
/* It is considered real but fake if it is translated to X RandR. */
this->fake = 1;
# ifdef HAVE_LIBGAMMA_METHOD_X_RANDR
this->real = 1;
# else
this->real = 0;
# endif
#else
/* It is real and not fake if we are running on Windows. */
this->fake = 0;
this->real = 1;
#endif
/* Gamma ramp adjustments are persistent. */
this->auto_restore = 0;
}
/**
* Initialise an allocated site state.
*
* @param this The site state to initialise.
* @param site The site identifier, unless it is `NULL` it must a
* `free`:able. One the state is destroyed the library
* will attempt to free it. There you should not free
* it yourself, and it must not be a string constant
* or allocate on the stack. Note however that it will
* not be free:d if this function fails.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_site_initialise(libgamma_site_state_t* restrict this,
char* restrict site)
{
this->partitions_available = 1;
return site != NULL ? LIBGAMMA_NO_SUCH_SITE : 0;
}
/**
* Release all resources held by a site state.
*
* @param this The site state.
*/
void libgamma_w32_gdi_site_destroy(libgamma_site_state_t* restrict this)
{
(void) this;
}
/**
* Restore the gamma ramps all CRTC:s with a site to the system settings.
*
* @param this The site state.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_site_restore(libgamma_site_state_t* restrict this)
{
(void) this;
return errno = ENOTSUP, LIBGAMMA_ERRNO_SET;
}
/**
* Initialise an allocated partition state.
*
* @param this The partition state to initialise.
* @param site The site state for the site that the partition belongs to.
* @param partition The the index of the partition within the site.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_partition_initialise(libgamma_partition_state_t* restrict this,
libgamma_site_state_t* restrict site, size_t partition)
{
DWORD n = 0;
DISPLAY_DEVICE display;
(void) site;
if (partition != 0)
return LIBGAMMA_NO_SUCH_PARTITION;
/* Count CRTC:s by iteration over all possible identifiers
until we reach on that does not exist. */
display.cb = sizeof(DISPLAY_DEVICE);
while (EnumDisplayDevices(NULL, n, &display, 0))
if (n++, n == 0)
return LIBGAMMA_IMPOSSIBLE_AMOUNT;
this->crtcs_available = (size_t)n;
return 0;
}
/**
* Release all resources held by a partition state.
*
* @param this The partition state.
*/
void libgamma_w32_gdi_partition_destroy(libgamma_partition_state_t* restrict this)
{
(void) this;
}
/**
* Restore the gamma ramps all CRTC:s with a partition to the system settings.
*
* @param this The partition state.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_partition_restore(libgamma_partition_state_t* restrict this)
{
(void) this;
return errno = ENOTSUP, LIBGAMMA_ERRNO_SET;
}
/**
* Initialise an allocated CRTC state.
*
* @param this The CRTC state to initialise.
* @param partition The partition state for the partition that the CRTC belongs to.
* @param crtc The the index of the CRTC within the site.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_crtc_initialise(libgamma_crtc_state_t* restrict this,
libgamma_partition_state_t* restrict partition, size_t crtc)
{
DISPLAY_DEVICE display;
HDC context;
(void) partition;
this->data = NULL;
/* Windows's API mandates this... */
display.cb = sizeof(DISPLAY_DEVICE);
/* Get identifier for selected CRTC. */
if (!EnumDisplayDevices(NULL, (DWORD)crtc, &display, 0))
return LIBGAMMA_NO_SUCH_CRTC;
/* Check that the connector is enabled,
* newer versions of Windows will always pass.
* (According to w32's documentation, but that
* that is a load of crap.)*/
if (!(display.StateFlags & DISPLAY_DEVICE_ACTIVE))
return LIBGAMMA_CONNECTOR_DISABLED;
/* Acquire CRTC connection. */
context = CreateDC(TEXT("DISPLAY"), display.DeviceName, NULL, NULL);
if (context == NULL)
return LIBGAMMA_OPEN_CRTC_FAILED;
this->data = context;
return 0;
}
/**
* Release all resources held by a CRTC state.
*
* @param this The CRTC state.
*/
void libgamma_w32_gdi_crtc_destroy(libgamma_crtc_state_t* restrict this)
{
if (this->data)
ReleaseDC(NULL, this->data);
}
/**
* Restore the gamma ramps for a CRTC to the system settings for that CRTC.
*
* @param this The CRTC state.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_crtc_restore(libgamma_crtc_state_t* restrict this)
{
(void) this;
return errno = ENOTSUP, LIBGAMMA_ERRNO_SET;
}
/**
* Read information about a CRTC.
*
* @param this Instance of a data structure to fill with the information about the CRTC.
* @param crtc The state of the CRTC whose information should be read.
* @param fields OR:ed identifiers for the information about the CRTC that should be read
* @return Zero on success, -1 on error. On error refer to the error reports in `this`.
*/
int libgamma_w32_gdi_get_crtc_information(libgamma_crtc_information_t* restrict this,
libgamma_crtc_state_t* restrict crtc, int32_t fields)
{
#define KNOWN_FIELDS (LIBGAMMA_CRTC_INFO_GAMMA_SIZE | LIBGAMMA_CRTC_INFO_GAMMA_DEPTH)
#define _E(FIELD) ((fields & FIELD) ? LIBGAMMA_CRTC_INFO_NOT_SUPPORTED : 0)
(void) crtc;
/* Windows GDI does not support EDID or monitor dimensions. */
this->edid_error = _E(LIBGAMMA_CRTC_INFO_EDID);
this->width_mm_error = _E(LIBGAMMA_CRTC_INFO_WIDTH_MM);
this->height_mm_error = _E(LIBGAMMA_CRTC_INFO_HEIGHT_MM);
this->width_mm_edid_error = _E(LIBGAMMA_CRTC_INFO_WIDTH_MM_EDID);
this->height_mm_edid_error = _E(LIBGAMMA_CRTC_INFO_HEIGHT_MM_EDID);
/* Windows GDI have fixed gamma ramp sizes. */
this->red_gamma_size = GAMMA_RAMP_SIZE;
this->green_gamma_size = GAMMA_RAMP_SIZE;
this->blue_gamma_size = GAMMA_RAMP_SIZE;
this->gamma_size_error = 0;
/* Windows GDI have fixed gamma ramp depth. */
this->gamma_depth = 16;
this->gamma_depth_error = 0;
/* It is possible to query Windows GDI whether the device
have gamma ramp support. It cannot fail. However, I think
the result is incorrect if multiple monitors are active,
so we cannot include this. */
/*
if ((fields & LIBGAMMA_CRTC_INFO_GAMMA_SUPPORT))
this->gamma_support = GetDeviceCaps(crtc->data, COLORMGMTCAPS) == CM_GAMMA_RAMP;
this->gamma_support_error = 0;
*/
this->gamma_support_error = _E(LIBGAMMA_CRTC_INFO_GAMMA_SUPPORT);
/* Windows GDI does not support EDID or connector information. */
this->subpixel_order_error = _E(LIBGAMMA_CRTC_INFO_SUBPIXEL_ORDER);
this->active_error = _E(LIBGAMMA_CRTC_INFO_ACTIVE);
this->connector_name_error = _E(LIBGAMMA_CRTC_INFO_CONNECTOR_NAME);
this->connector_type_error = _E(LIBGAMMA_CRTC_INFO_CONNECTOR_TYPE);
this->gamma_error = _E(LIBGAMMA_CRTC_INFO_GAMMA);
/* There was a failure if and only if unsupport field was requested. */
return (fields & ~KNOWN_FIELDS) ? -1 : 0;
#undef _E
#undef KNOWN_FIELDS
}
/**
* Get the current gamma ramps for a CRTC, 16-bit gamma-depth version.
*
* @param this The CRTC state.
* @param ramps The gamma ramps to fill with the current values.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_crtc_get_gamma_ramps16(libgamma_crtc_state_t* restrict this,
libgamma_gamma_ramps16_t* restrict ramps)
{
#ifdef DEBUG
/* Windows GDI have fixed gamma ramp sizes. */
if ((ramps-> red_size != GAMMA_RAMP_SIZE) ||
(ramps->green_size != GAMMA_RAMP_SIZE) ||
(ramps-> blue_size != GAMMA_RAMP_SIZE))
return LIBGAMMA_WRONG_GAMMA_RAMP_SIZE;
#endif
/* Read current gamma ramps. */
if (!GetDeviceGammaRamp(this->data, ramps->red))
return LIBGAMMA_GAMMA_RAMP_READ_FAILED;
return 0;
}
/**
* Set the gamma ramps for a CRTC, 16-bit gamma-depth version.
*
* @param this The CRTC state.
* @param ramps The gamma ramps to apply.
* @return Zero on success, otherwise (negative) the value of an
* error identifier provided by this library.
*/
int libgamma_w32_gdi_crtc_set_gamma_ramps16(libgamma_crtc_state_t* restrict this,
libgamma_gamma_ramps16_t ramps)
{
#ifdef DEBUG
/* Windows GDI have fixed gamma ramp sizes. */
if ((ramps. red_size != GAMMA_RAMP_SIZE) ||
(ramps.green_size != GAMMA_RAMP_SIZE) ||
(ramps. blue_size != GAMMA_RAMP_SIZE))
return LIBGAMMA_WRONG_GAMMA_RAMP_SIZE;
#endif
/* Apply gamma ramps. */
if (!SetDeviceGammaRamp(this->data, ramps.red))
return LIBGAMMA_GAMMA_RAMP_WRITE_FAILED;
return 0;
}
