static void
cdisplay_gamma_convert_buffer (GimpColorDisplay *display,
GeglBuffer *buffer,
GeglRectangle *area)
{
CdisplayGamma *gamma = CDISPLAY_GAMMA (display);
GeglBufferIterator *iter;
gdouble one_over_gamma;
one_over_gamma = 1.0 / gamma->gamma;
iter = gegl_buffer_iterator_new (buffer, area, 0,
babl_format ("R'G'B'A float"),
GEGL_ACCESS_READWRITE, GEGL_ABYSS_NONE);
while (gegl_buffer_iterator_next (iter))
{
gfloat *data = iter->data[0];
gint count = iter->length;
while (count--)
{
*data = pow (*data, one_over_gamma); data++;
*data = pow (*data, one_over_gamma); data++;
*data = pow (*data, one_over_gamma); data++;
data++;
}
}
}
static void
cdisplay_gamma_convert_surface (GimpColorDisplay *display,
cairo_surface_t *surface)
{
CdisplayGamma *gamma = CDISPLAY_GAMMA (display);
gint width = cairo_image_surface_get_width (surface);
gint height = cairo_image_surface_get_height (surface);
gint stride = cairo_image_surface_get_stride (surface);
guchar *buf = cairo_image_surface_get_data (surface);
cairo_format_t fmt = cairo_image_surface_get_format (surface);
gint i, j, skip;
gint r, g, b, a;
if (fmt != CAIRO_FORMAT_ARGB32)
return;
/* You will not be using the entire buffer most of the time.
* Hence, the simplistic code for this is as follows:
*
* for (j = 0; j < height; j++)
* {
* for (i = 0; i < width * bpp; i++)
* buf[i] = lookup[buf[i]];
* buf += bpl;
* }
*/
j = height;
skip = stride - 4 * width;
while (j--)
{
i = width;
while (i--)
{
GIMP_CAIRO_ARGB32_GET_PIXEL (buf, r, g, b, a);
r = gamma->lookup[r];
g = gamma->lookup[g];
b = gamma->lookup[b];
GIMP_CAIRO_ARGB32_SET_PIXEL (buf, r, g, b, a);
buf += 4;
}
buf += skip;
}
}
static void
cdisplay_gamma_set_property (GObject *object,
guint property_id,
const GValue *value,
GParamSpec *pspec)
{
CdisplayGamma *gamma = CDISPLAY_GAMMA (object);
switch (property_id)
{
case PROP_GAMMA:
cdisplay_gamma_set_gamma (gamma, g_value_get_double (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static GtkWidget *
cdisplay_gamma_configure (GimpColorDisplay *display)
{
CdisplayGamma *gamma = CDISPLAY_GAMMA (display);
GtkWidget *hbox;
GtkWidget *label;
GtkWidget *spinbutton;
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
label = gtk_label_new_with_mnemonic (_("_Gamma:"));
gtk_box_pack_start (GTK_BOX (hbox), label, FALSE, FALSE, 0);
gtk_widget_show (label);
spinbutton = gimp_prop_spin_button_new (G_OBJECT (gamma), "gamma",
0.1, 1.0, 3);
gtk_box_pack_start (GTK_BOX (hbox), spinbutton, FALSE, FALSE, 0);
gtk_widget_show (spinbutton);
gtk_label_set_mnemonic_widget (GTK_LABEL (label), spinbutton);
return hbox;
}
static void
cdisplay_gamma_convert (GimpColorDisplay *display,
guchar *buf,
gint width,
gint height,
gint bpp,
gint bpl)
{
CdisplayGamma *gamma = CDISPLAY_GAMMA (display);
gint i, j = height;
/* You will not be using the entire buffer most of the time.
* Hence, the simplistic code for this is as follows:
*
* for (j = 0; j < height; j++)
* {
* for (i = 0; i < width * bpp; i++)
* buf[i] = lookup[buf[i]];
* buf += bpl;
* }
*/
width *= bpp;
bpl -= width;
while (j--)
{
i = width;
while (i--)
{
*buf = gamma->lookup[*buf];
buf++;
}
buf += bpl;
}
}