1 files changed, 120 insertions, 0 deletions
diff --git a/src/engine/julia.c b/src/engine/julia.c
new file mode 100644
index 0000000..d471bc8
--- /dev/null
+++ b/src/engine/julia.c
@@ -0,0 +1,120 @@
+#ifdef _plan9_
+#include <u.h>
+#include <stdio.h>
+#include <libc.h>
+#else
+#include <math.h>
+#include <string.h>
+#include <config.h>
+#ifndef NO_MALLOC_H
+#include <malloc.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#endif
+#include <filter.h>
+#include "julia.h"
+#include <config.h>
+#ifdef HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
+#include <filter.h>
+#include <archaccel.h>
+
+
+/*most of code was moved to docalc.c */
+
+#ifdef STATISTICS
+int iters2, guessed2, unguessed2, total2;
+#endif
+void
+init_julia(struct image *img, number_t rangep, number_t range,
+	   number_t xdelta, number_t ystep)
+{
+    int i, j, x, y;
+    register number_t im;
+    unsigned char *addr, **addr1 = img->currlines;
+    for (i = 0; i < img->height; i++) {
+	im = IMIN + (i + 0.5) * ystep;
+	x = (int) (sqrt(rangep - im * im) * xdelta + 0.5);
+	if (!i || i == img->height - 1)
+	    x = 0;
+	addr = addr1[i];
+	y = img->width / 2 - x;
+	if (y < 1)
+	    y = 1;
+	for (j = 0; j < y; j++) {
+	    addr[j] = 1;
+	}
+	y = img->width;
+	j = img->width / 2 + x;
+	if (j >= img->width)
+	    j = img->width - 1;
+	for (j = img->width / 2 + x; j < y; j++) {
+	    addr[j] = 1;
+	}
+    }
+    for (i = 0; i < img->height; i++) {
+	addr = addr1[i];
+	memset_long((char *) addr, NOT_CALCULATED, img->width);
+    }
+}
+
+
+static int requirement(struct filter *f, struct requirements *r)
+{
+    r->nimages = 1;
+    r->flags = 0;
+    r->supportedmask = SMALLITER;
+    return (f->next->action->requirement(f->next, r));
+}
+
+static int initialize(struct filter *f, struct initdata *i)
+{
+    inhermisc(f, i);
+    f->image = i->image;
+    return (1);
+}
+
+static struct filter *getinstance(CONST struct filteraction *a)
+{
+    struct filter *f = createfilter(a);
+    f->name = "Julia generator";
+    return (f);
+}
+
+static void destroyinstance(struct filter *f)
+{
+    free(f);
+}
+
+static int doit(struct filter *f, int flags, int time)
+{
+    /*if(f->image->nimages==2) f->image->flip(f->image); */
+    if (f->fractalc->currentformula->calculate_julia != NULL) {
+	f->fractalc->currentformula->calculate_julia(f->image,
+						     f->fractalc->pre,
+						     f->fractalc->pim);
+	return (CHANGED);
+    }
+#ifdef STATISTICS
+    printf("Total guessed %i, unguessed %i, iterations %i\n", guessed2,
+	   unguessed2, iters2);
+#endif
+
+    return 0;
+}
+
+CONST struct filteraction julia_filter = {
+    "Julia generator",
+    "julia",
+    0,
+    getinstance,
+    destroyinstance,
+    doit,
+    requirement,
+    initialize,
+    convertupgeneric,
+    convertdowngeneric,
+    NULL,
+};