1 files changed, 66 insertions, 0 deletions
diff --git a/src/engine/edged.c b/src/engine/edged.c
new file mode 100644
index 0000000..918f308
--- /dev/null
+++ b/src/engine/edged.c
@@ -0,0 +1,66 @@
+#ifndef UNSUPPORTED
+static void do_edge(void *data, struct taskinfo *task, int r1, int r2)
+{
+    struct filter *f = (struct filter *) data;
+    int y;
+    unsigned int *pixels = f->image->palette->pixels;
+    register unsigned int black = f->image->palette->pixels[0];
+    register cpixel_t *output, *end;
+    register spixel_t *up, *down, *input;
+    for (y = r1; y < r2; y++) {
+	output = p_add(((cpixel_t *) f->image->currlines[y]), 1);
+	input = ((spixel_t *) f->childimage->currlines[y]) + 1;
+	if (y != 0)
+	    up = ((spixel_t *) f->childimage->currlines[y - 1]) + 2;
+	else
+	    up = ((spixel_t *) f->childimage->currlines[y]) + 2;
+	if (y != f->image->height - 1)
+	    down = ((spixel_t *) f->childimage->currlines[y + 1]) + 2;
+	else
+	    down = ((spixel_t *) f->childimage->currlines[y]) + 2;
+	end =
+	    p_add(((cpixel_t *) f->image->currlines[y]),
+		  f->image->width - 1);
+	p_setp(output, -1, 0);
+	p_setp(output, f->image->width - 2, 0);
+	while (output < end) {
+	    if (input[1] != input[0] || input[0] != up[0]
+		|| input[0] != down[0]) {
+		if (output < end - 2) {
+		    p_set(output, pixels[input[0]]);
+		    p_setp(output, 1, pixels[input[1]]);
+		    p_setp(output, 2, pixels[input[2]]);
+		    p_inc(output, 3);
+		    input += 3;
+		    up += 3;
+		    down += 3;
+		    while (output < end - 1
+			   && (input[0] != up[-1] || input[0] != down[-1]))
+		    {
+			p_set(output, pixels[input[0]]);
+			p_setp(output, 1, pixels[input[1]]);
+			p_inc(output, 2);
+			input += 2;
+			up += 2;
+			down += 2;
+		    }
+		    if (output < end
+			&& (input[-1] != input[0] || up[-2] != input[0]
+			    || down[-2] != input[0])) {
+			p_set(output, pixels[input[0]]);
+			p_inc(output, 1);
+			input++;
+			up++;
+			down++;
+		    }
+		} else
+		    p_set(output, pixels[*input]), p_inc(output, 1),
+			input++, up++, down++;
+	    } else
+		p_set(output, black), p_inc(output, 1), input++, up++,
+		    down++;
+	}
+    }
+}
+#endif
+#undef do_edge