Use the prefix 'gamma' for gamma adjustment source files.

1 files changed, 127 insertions, 0 deletions

diff --git a/src/gamma-w32gdi.c b/src/gamma-w32gdi.c
new file mode 100644
index 0000000..d1b6533
--- /dev/null
+++ b/src/gamma-w32gdi.c
@@ -0,0 +1,127 @@
+/* gamma-w32gdi.c -- Windows GDI gamma adjustment source
+   This file is part of Redshift.
+
+   Redshift 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.
+
+   Redshift 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 Redshift.  If not, see <http://www.gnu.org/licenses/>.
+
+   Copyright (c) 2010  Jon Lund Steffensen <jonlst@gmail.com>
+*/
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#define WINVER  0x0500
+#include <windows.h>
+#include <wingdi.h>
+
+#ifdef ENABLE_NLS
+# include <libintl.h>
+# define _(s) gettext(s)
+#else
+# define _(s) s
+#endif
+
+#include "w32gdi.h"
+#include "colorramp.h"
+
+#define GAMMA_RAMP_SIZE  256
+
+
+int
+w32gdi_init(w32gdi_state_t *state, char *args)
+{
+	BOOL r;
+
+	/* Open device context */
+	state->hDC = GetDC(NULL);
+	if (state->hDC == NULL) {
+		fputs(_("Unable to open device context.\n"), stderr);
+		return -1;
+	}
+
+	/* Check support for gamma ramps */
+	int cmcap = GetDeviceCaps(state->hDC, COLORMGMTCAPS);
+	if (cmcap != CM_GAMMA_RAMP) {
+		fputs(_("Display device does not support gamma ramps.\n"),
+		      stderr);
+		return -1;
+	}
+
+	/* Allocate space for saved gamma ramps */
+	state->saved_ramps = malloc(3*GAMMA_RAMP_SIZE*sizeof(WORD));
+	if (state->saved_ramps == NULL) {
+		perror("malloc");
+		ReleaseDC(NULL, state->hDC);
+		return -1;
+	}
+
+	/* Save current gamma ramps so we can restore them at program exit */
+	r = GetDeviceGammaRamp(state->hDC, state->saved_ramps);
+	if (!r) {
+		fputs(_("Unable to save current gamma ramp.\n"), stderr);
+		ReleaseDC(NULL, state->hDC);
+		return -1;
+	}
+
+	return 0;
+}
+
+void
+w32gdi_free(w32gdi_state_t *state)
+{
+	/* Free saved ramps */
+	free(state->saved_ramps);
+
+	/* Release device context */
+	ReleaseDC(NULL, state->hDC);
+}
+
+void
+w32gdi_restore(w32gdi_state_t *state)
+{
+	/* Restore gamma ramps */
+	BOOL r = SetDeviceGammaRamp(state->hDC, state->saved_ramps);
+	if (!r) fputs(_("Unable to restore gamma ramps.\n"), stderr);
+}
+
+int
+w32gdi_set_temperature(w32gdi_state_t *state, int temp, float gamma[3])
+{
+	BOOL r;
+
+	/* Create new gamma ramps */
+	WORD *gamma_ramps = malloc(3*GAMMA_RAMP_SIZE*sizeof(WORD));
+	if (gamma_ramps == NULL) {
+		perror("malloc");
+		return -1;
+	}
+
+	WORD *gamma_r = &gamma_ramps[0*GAMMA_RAMP_SIZE];
+	WORD *gamma_g = &gamma_ramps[1*GAMMA_RAMP_SIZE];
+	WORD *gamma_b = &gamma_ramps[2*GAMMA_RAMP_SIZE];
+
+	colorramp_fill(gamma_r, gamma_g, gamma_b, GAMMA_RAMP_SIZE,
+		       temp, gamma);
+
+	/* Set new gamma ramps */
+	r = SetDeviceGammaRamp(state->hDC, gamma_ramps);
+	if (!r) {
+		fputs(_("Unable to set gamma ramps.\n"), stderr);
+		free(gamma_ramps);
+		return -1;
+	}
+
+	free(gamma_ramps);
+
+	return 0;
+}