5 #define SHADOW_OFFSET (BLUR_RADIUS * 4 / 5)
6 #define SHADOW_OPACITY 0.75
14 gaussian (double x, double y, double r)
16 return ((1 / (2 * M_PI * r)) *
17 exp ((- (x * x + y * y)) / (2 * r * r)));
21 create_blur_filter (int radius)
27 filter = g_new0 (ConvFilter, 1);
28 filter->size = radius * 2 + 1;
29 filter->data = g_new (double, filter->size * filter->size);
33 for (y = 0 ; y < filter->size; y++)
35 for (x = 0 ; x < filter->size; x++)
37 sum += filter->data[y * filter->size + x] = gaussian (x - (filter->size >> 1),
38 y - (filter->size >> 1),
43 for (y = 0; y < filter->size; y++)
45 for (x = 0; x < filter->size; x++)
47 filter->data[y * filter->size + x] /= sum;
56 create_shadow (GdkPixbuf *src)
61 static ConvFilter *filter = NULL;
62 int src_rowstride, dest_rowstride;
63 int src_bpp, dest_bpp;
65 guchar *src_pixels, *dest_pixels;
68 filter = create_blur_filter (BLUR_RADIUS);
70 width = gdk_pixbuf_get_width (src) + BLUR_RADIUS * 2 + SHADOW_OFFSET;
71 height = gdk_pixbuf_get_height (src) + BLUR_RADIUS * 2 + SHADOW_OFFSET;
73 dest = gdk_pixbuf_new (gdk_pixbuf_get_colorspace (src),
74 gdk_pixbuf_get_has_alpha (src),
75 gdk_pixbuf_get_bits_per_sample (src),
77 gdk_pixbuf_fill (dest, 0);
78 src_pixels = gdk_pixbuf_get_pixels (src);
79 src_rowstride = gdk_pixbuf_get_rowstride (src);
80 src_bpp = gdk_pixbuf_get_has_alpha (src) ? 4 : 3;
82 dest_pixels = gdk_pixbuf_get_pixels (dest);
83 dest_rowstride = gdk_pixbuf_get_rowstride (dest);
84 dest_bpp = gdk_pixbuf_get_has_alpha (dest) ? 4 : 3;
86 for (y = 0; y < height; y++)
88 for (x = 0; x < width; x++)
90 int sumr = 0, sumg = 0, sumb = 0, suma = 0;
92 for (i = 0; i < filter->size; i++)
94 for (j = 0; j < filter->size; j++)
98 src_y = -(BLUR_RADIUS + SHADOW_OFFSET) + y - (filter->size >> 1) + i;
99 src_x = -(BLUR_RADIUS + SHADOW_OFFSET) + x - (filter->size >> 1) + j;
101 if (src_y < 0 || src_y > gdk_pixbuf_get_height (src) ||
102 src_x < 0 || src_x > gdk_pixbuf_get_width (src))
105 sumr += src_pixels [src_y * src_rowstride +
106 src_x * src_bpp + 0] *
107 filter->data [i * filter->size + j];
108 sumg += src_pixels [src_y * src_rowstride +
109 src_x * src_bpp + 1] *
110 filter->data [i * filter->size + j];
112 sumb += src_pixels [src_y * src_rowstride +
113 src_x * src_bpp + 2] *
114 filter->data [i * filter->size + j];
117 suma += src_pixels [src_y * src_rowstride +
118 src_x * src_bpp + 3] *
119 filter->data [i * filter->size + j];
126 dest_pixels [y * dest_rowstride +
127 x * dest_bpp + 3] = suma * SHADOW_OPACITY;
136 create_shadowed_pixbuf (GdkPixbuf *src)
140 dest = create_shadow (src);
142 gdk_pixbuf_composite (src, dest,
143 BLUR_RADIUS, BLUR_RADIUS,
144 gdk_pixbuf_get_width (src),
145 gdk_pixbuf_get_height (src),
146 BLUR_RADIUS, BLUR_RADIUS, 1.0, 1.0,
147 GDK_INTERP_NEAREST, 255);