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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 03:13:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 03:13:10 +0000
commit3c57dd931145d43f2b0aef96c4d178135956bf91 (patch)
tree3de698981e9f0cc2c4f9569b19a5f3595e741f6b /devel-docs/tools/shadow.c
parentInitial commit. (diff)
downloadgimp-3c57dd931145d43f2b0aef96c4d178135956bf91.tar.xz
gimp-3c57dd931145d43f2b0aef96c4d178135956bf91.zip
Adding upstream version 2.10.36.upstream/2.10.36
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--devel-docs/tools/shadow.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/devel-docs/tools/shadow.c b/devel-docs/tools/shadow.c
new file mode 100644
index 0000000..cf292c9
--- /dev/null
+++ b/devel-docs/tools/shadow.c
@@ -0,0 +1,149 @@
+#include "shadow.h"
+#include <math.h>
+
+#define BLUR_RADIUS 5
+#define SHADOW_OFFSET (BLUR_RADIUS * 4 / 5)
+#define SHADOW_OPACITY 0.75
+
+typedef struct {
+ int size;
+ double *data;
+} ConvFilter;
+
+static double
+gaussian (double x, double y, double r)
+{
+ return ((1 / (2 * M_PI * r)) *
+ exp ((- (x * x + y * y)) / (2 * r * r)));
+}
+
+static ConvFilter *
+create_blur_filter (int radius)
+{
+ ConvFilter *filter;
+ int x, y;
+ double sum;
+
+ filter = g_new0 (ConvFilter, 1);
+ filter->size = radius * 2 + 1;
+ filter->data = g_new (double, filter->size * filter->size);
+
+ sum = 0.0;
+
+ for (y = 0 ; y < filter->size; y++)
+ {
+ for (x = 0 ; x < filter->size; x++)
+ {
+ sum += filter->data[y * filter->size + x] = gaussian (x - (filter->size >> 1),
+ y - (filter->size >> 1),
+ radius);
+ }
+ }
+
+ for (y = 0; y < filter->size; y++)
+ {
+ for (x = 0; x < filter->size; x++)
+ {
+ filter->data[y * filter->size + x] /= sum;
+ }
+ }
+
+ return filter;
+
+}
+
+static GdkPixbuf *
+create_shadow (GdkPixbuf *src)
+{
+ int x, y, i, j;
+ int width, height;
+ GdkPixbuf *dest;
+ static ConvFilter *filter = NULL;
+ int src_rowstride, dest_rowstride;
+ int src_bpp, dest_bpp;
+
+ guchar *src_pixels, *dest_pixels;
+
+ if (!filter)
+ filter = create_blur_filter (BLUR_RADIUS);
+
+ width = gdk_pixbuf_get_width (src) + BLUR_RADIUS * 2 + SHADOW_OFFSET;
+ height = gdk_pixbuf_get_height (src) + BLUR_RADIUS * 2 + SHADOW_OFFSET;
+
+ dest = gdk_pixbuf_new (gdk_pixbuf_get_colorspace (src),
+ gdk_pixbuf_get_has_alpha (src),
+ gdk_pixbuf_get_bits_per_sample (src),
+ width, height);
+ gdk_pixbuf_fill (dest, 0);
+ src_pixels = gdk_pixbuf_get_pixels (src);
+ src_rowstride = gdk_pixbuf_get_rowstride (src);
+ src_bpp = gdk_pixbuf_get_has_alpha (src) ? 4 : 3;
+
+ dest_pixels = gdk_pixbuf_get_pixels (dest);
+ dest_rowstride = gdk_pixbuf_get_rowstride (dest);
+ dest_bpp = gdk_pixbuf_get_has_alpha (dest) ? 4 : 3;
+
+ for (y = 0; y < height; y++)
+ {
+ for (x = 0; x < width; x++)
+ {
+ int sumr = 0, sumg = 0, sumb = 0, suma = 0;
+
+ for (i = 0; i < filter->size; i++)
+ {
+ for (j = 0; j < filter->size; j++)
+ {
+ int src_x, src_y;
+
+ src_y = -(BLUR_RADIUS + SHADOW_OFFSET) + y - (filter->size >> 1) + i;
+ src_x = -(BLUR_RADIUS + SHADOW_OFFSET) + x - (filter->size >> 1) + j;
+
+ if (src_y < 0 || src_y > gdk_pixbuf_get_height (src) ||
+ src_x < 0 || src_x > gdk_pixbuf_get_width (src))
+ continue;
+
+ sumr += src_pixels [src_y * src_rowstride +
+ src_x * src_bpp + 0] *
+ filter->data [i * filter->size + j];
+ sumg += src_pixels [src_y * src_rowstride +
+ src_x * src_bpp + 1] *
+ filter->data [i * filter->size + j];
+
+ sumb += src_pixels [src_y * src_rowstride +
+ src_x * src_bpp + 2] *
+ filter->data [i * filter->size + j];
+
+ if (src_bpp == 4)
+ suma += src_pixels [src_y * src_rowstride +
+ src_x * src_bpp + 3] *
+ filter->data [i * filter->size + j];
+
+
+ }
+ }
+
+ if (dest_bpp == 4)
+ dest_pixels [y * dest_rowstride +
+ x * dest_bpp + 3] = suma * SHADOW_OPACITY;
+
+ }
+ }
+
+ return dest;
+}
+
+GdkPixbuf *
+create_shadowed_pixbuf (GdkPixbuf *src)
+{
+ GdkPixbuf *dest;
+
+ dest = create_shadow (src);
+
+ gdk_pixbuf_composite (src, dest,
+ BLUR_RADIUS, BLUR_RADIUS,
+ gdk_pixbuf_get_width (src),
+ gdk_pixbuf_get_height (src),
+ BLUR_RADIUS, BLUR_RADIUS, 1.0, 1.0,
+ GDK_INTERP_NEAREST, 255);
+ return dest;
+}