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|
--- /tmp/config.h.in 2006-12-23 00:00:38.000000000 +0100
+++ gtk+-2.10.6/config.h.in 2006-12-23 00:01:05.632227000 +0100
@@ -253,3 +253,7 @@
/* Define to `int' if <sys/types.h> doesn't define. */
#undef uid_t
+
+/* Define to use integer math rather than floating point where possible. */
+#undef ENABLE_INTEGER_PIXOPS
+
--- /tmp/configure.in 2006-12-23 00:02:16.000000000 +0100
+++ gtk+-2.10.6/configure.in 2006-12-23 00:05:11.172227000 +0100
@@ -203,6 +203,15 @@
[AC_HELP_STRING([--disable-rebuilds],
[disable all source autogeneration rules])],,
[enable_rebuilds=yes])
+AC_ARG_ENABLE(integer-pixops,
+ [AC_HELP_STRING([--enable-integer-pixops],
+ [use integer math where possible])],,
+ [enable_integer_pixops=no])
+
+if test "x$enable_integer_pixops" = "xyes"; then
+ AC_DEFINE(ENABLE_INTEGER_PIXOPS)
+fi
+
AC_ARG_ENABLE(visibility,
[AC_HELP_STRING([--disable-visibility],
[don't use ELF visibility attributes])],,
--- /tmp/pixops.c 2006-12-23 10:04:02.000000000 +0100
+++ gtk+-2.10.6/gdk-pixbuf/pixops/pixops.c 2006-12-23 10:04:21.772227000 +0100
@@ -28,6 +28,10 @@
#define SUBSAMPLE_MASK ((1 << SUBSAMPLE_BITS)-1)
#define SCALE_SHIFT 16
+#ifdef ENABLE_INTEGER_PIXOPS
+#define FRAC 0x10000ULL
+#endif
+
typedef struct _PixopsFilter PixopsFilter;
typedef struct _PixopsFilterDimension PixopsFilterDimension;
@@ -972,6 +976,29 @@
(*pixel_func) (dest, dest_x, dest_channels, dest_has_alpha, src_has_alpha, check_size, color1, color2, r, g, b, a);
}
+#ifdef ENABLE_INTEGER_PIXOPS
+
+static void
+correct_total (int *weights,
+ int n_x,
+ int n_y,
+ int total,
+ unsigned long overall_alpha)
+{
+ int correction = (int)(overall_alpha - total);
+ int i;
+ for (i = n_x * n_y - 1; i >= 0; i--)
+ {
+ if (*(weights + i) + correction >= 0)
+ {
+ *(weights + i) += correction;
+ break;
+ }
+ }
+}
+
+#else
+
static void
correct_total (int *weights,
int n_x,
@@ -998,6 +1025,8 @@
}
}
+#endif
+
static int *
make_filter_table (PixopsFilter *filter)
{
@@ -1026,7 +1055,11 @@
*(pixel_weights + n_x * i + j) = weight;
}
- correct_total (pixel_weights, n_x, n_y, total, filter->overall_alpha);
+#ifdef ENABLE_INTEGER_PIXOPS
+ correct_total (pixel_weights, n_x, n_y, total, overall_alpha * FRAC);
+#else
+ correct_total (pixel_weights, n_x, n_y, total, overall_alpha);
+#endif
}
return weights;
@@ -1178,6 +1211,93 @@
/* Compute weights for reconstruction by replication followed by
* sampling with a box filter
*/
+#ifdef ENABLE_INTEGER_PIXOPS
+
+static void
+tile_make_weights (PixopsFilter *filter, double x_scale_d, double y_scale_d, double overall_alpha_d)
+{
+ int i_offset, j_offset;
+ unsigned long x_scale = x_scale_d * FRAC;
+ unsigned long y_scale = y_scale_d * FRAC;
+ unsigned long overall_alpha = overall_alpha_d * FRAC;
+ unsigned long x_scale_r = FRAC / x_scale;
+ unsigned long y_scale_r = FRAC / y_scale;
+
+ int n_x = ceil(1/x_scale_d + 1);
+ int n_y = ceil(1/y_scale_d + 1);
+
+ filter->x_offset = 0;
+ filter->y_offset = 0;
+ filter->n_x = n_x;
+ filter->n_y = n_y;
+ filter->weights = g_new (int, SUBSAMPLE * SUBSAMPLE * n_x * n_y);
+
+ for (i_offset=0; i_offset<SUBSAMPLE; i_offset++)
+ for (j_offset=0; j_offset<SUBSAMPLE; j_offset++)
+ {
+ int *pixel_weights = filter->weights + ((i_offset*SUBSAMPLE) + j_offset) * n_x * n_y;
+ unsigned long x = j_offset * FRAC / SUBSAMPLE;
+ unsigned long y = i_offset * FRAC / SUBSAMPLE;
+ int i,j;
+ int total = 0;
+
+ for (i = 0; i < n_y; i++)
+ {
+ unsigned long tw, th;
+
+ if (i < y)
+ {
+
+ if (i + FRAC > y)
+ th = MIN(i+FRAC, y + y_scale_r) - y;
+ else
+ th = 0;
+ }
+ else
+ {
+ if (y + FRAC/y_scale > i)
+ th = MIN(i+FRAC, y + y_scale_r) - i;
+ else
+ th = 0;
+ }
+
+ for (j = 0; j < n_x; j++)
+ {
+ int weight;
+
+ if (j < x)
+ {
+ if (j + FRAC > x)
+ tw = MIN(j+FRAC, x + x_scale_r) - x;
+ else
+ tw = 0;
+ }
+ else
+ {
+ if (x + FRAC/x_scale > j)
+ tw = MIN(j+FRAC, x + x_scale_r) - j;
+ else
+ tw = 0;
+ }
+
+ {
+ unsigned long lweight = (tw * x_scale) / FRAC;
+ lweight = (lweight * th) / FRAC;
+ lweight = (lweight * y_scale) / FRAC;
+ lweight = (lweight * overall_alpha) / FRAC;
+ weight = lweight;
+ }
+ total += weight;
+ *(pixel_weights + n_x * i + j) = weight;
+ }
+ }
+
+ correct_total (pixel_weights, n_x, n_y, total, overall_alpha);
+ }
+}
+
+#else
+
static void
tile_make_weights (PixopsFilterDimension *dim,
double scale)
@@ -1216,10 +1336,151 @@
}
}
+#endif
+
/* Compute weights for a filter that, for minification
* is the same as 'tiles', and for magnification, is bilinear
* reconstruction followed by a sampling with a delta function.
*/
+#ifdef ENABLE_INTEGER_PIXOPS
+
+static void
+bilinear_magnify_make_weights (PixopsFilter *filter, double x_scale_d, double y_scale_d, double overall_alpha_d)
+{
+ int i_offset, j_offset;
+ unsigned long *x_weights, *y_weights;
+ int n_x, n_y;
+ unsigned long x_scale = x_scale_d * FRAC;
+ unsigned long y_scale = y_scale_d * FRAC;
+ unsigned long overall_alpha = overall_alpha_d * FRAC;
+ unsigned long x_scale_r = (FRAC / x_scale_d);
+ unsigned long y_scale_r = (FRAC / y_scale_d);
+
+ if (x_scale > FRAC) /* Bilinear */
+ {
+ n_x = 2;
+ filter->x_offset = 0.5 * (1/x_scale_d - 1);
+ }
+ else /* Tile */
+ {
+ n_x = ceil(1.0 + 1.0/x_scale_d);
+ filter->x_offset = 0.0;
+ }
+
+ if (y_scale > FRAC) /* Bilinear */
+ {
+ n_y = 2;
+ filter->y_offset = 0.5 * (1/y_scale_d - 1);
+ }
+ else /* Tile */
+ {
+ n_y = ceil(1.0 + 1.0/y_scale_d);
+ filter->y_offset = 0.0;
+ }
+
+ filter->n_y = n_y;
+ filter->n_x = n_x;
+ filter->weights = g_new (int, SUBSAMPLE * SUBSAMPLE * n_x * n_y);
+
+ x_weights = g_new (unsigned long, n_x);
+ y_weights = g_new (unsigned long, n_y);
+
+ for (i_offset=0; i_offset<SUBSAMPLE; i_offset++)
+ for (j_offset=0; j_offset<SUBSAMPLE; j_offset++)
+ {
+ int *pixel_weights = filter->weights + ((i_offset*SUBSAMPLE) + j_offset) * n_x * n_y;
+ unsigned long x = j_offset * FRAC / SUBSAMPLE;
+ unsigned long y = i_offset * FRAC / SUBSAMPLE;
+ int i,j;
+ int total = 0;
+
+ if (x_scale > FRAC) /* Bilinear */
+ {
+ for (i = 0; i < n_x; i++)
+ {
+ /* x_weights[i] = ((i == 0) ? (1 - x) : x) / x_scale; */
+ unsigned long w = (((i == 0) ? (FRAC - x) : x) * x_scale_r);
+ x_weights[i] = w / FRAC;
+ }
+ }
+ else /* Tile */
+ {
+ /* x
+ * ---------|--.-|----|--.-|------- SRC
+ * ------------|---------|--------- DEST
+ */
+ for (i = 0; i < n_x; i++)
+ {
+ if (i < x)
+ {
+ if (i + 1 > x)
+ x_weights[i] = MIN(FRAC*(i+1), FRAC * x + (((unsigned long long)(FRAC * FRAC)) / (unsigned long)x_scale)) - (x * FRAC);
+ else
+ x_weights[i] = 0;
+ }
+ else
+ {
+ if (x + 1/x_scale > i)
+ x_weights[i] = MIN(FRAC*(i+1), FRAC * x + (((unsigned long long)(FRAC * FRAC)) / (unsigned long)x_scale)) - (i * FRAC);
+ else
+ x_weights[i] = 0;
+ }
+ }
+ }
+
+ if (y_scale > FRAC) /* Bilinear */
+ {
+ for (i = 0; i < n_y; i++)
+ {
+ unsigned long w = ((unsigned long)((i == 0) ? (FRAC - y) : y) * y_scale_r);
+ y_weights[i] = w / FRAC;
+ }
+ }
+ else /* Tile */
+ {
+ /* y
+ * ---------|--.-|----|--.-|------- SRC
+ * ------------|---------|--------- DEST
+ */
+ for (i = 0; i < n_y; i++)
+ {
+ if (i < y)
+ {
+ if (i + 1 > y)
+ y_weights[i] = MIN(FRAC*(i+1), FRAC * y + (FRAC * FRAC / (unsigned long)y_scale)) - (y * FRAC);
+ else
+ y_weights[i] = 0;
+ }
+ else
+ {
+ if (y + 1/y_scale > i)
+ y_weights[i] = MIN(FRAC*(i+1), FRAC * y + (FRAC * FRAC / (unsigned long)y_scale)) - (i * FRAC);
+ else
+ y_weights[i] = 0;
+ }
+ }
+ }
+
+ for (i = 0; i < n_y; i++)
+ for (j = 0; j < n_x; j++)
+ {
+ unsigned long long weight = (x_weights[j] * x_scale) / FRAC;
+ weight = (weight * y_weights[i]) / FRAC;
+ weight = (weight * y_scale) / FRAC;
+ weight = (weight * overall_alpha) / FRAC;
+ *(pixel_weights + n_x * i + j) = (unsigned long)weight;
+ total += (unsigned long)weight;
+ }
+
+ correct_total (pixel_weights, n_x, n_y, total, overall_alpha);
+ }
+
+ g_free (x_weights);
+ g_free (y_weights);
+}
+
+#else
+
static void
bilinear_magnify_make_weights (PixopsFilterDimension *dim,
double scale)
@@ -1283,6 +1544,8 @@
}
}
+#endif
+
/* Computes the integral from b0 to b1 of
*
* f(x) = x; 0 <= x < 1
|
