Merge pull request #4 from ph1l/stars

stars: add starfield simulator from ph1l/stars

1 files changed, 63 insertions, 0 deletions

diff --git a/modules/stars/stars.c b/modules/stars/stars.c
new file mode 100644
index 0000000..e009714
--- /dev/null
+++ b/modules/stars/stars.c
@@ -0,0 +1,63 @@
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+#include <time.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "draw.h"
+#include "fb.h"
+#include "rototiller.h"
+#include "starslib.h"
+
+/* Copyright (C) 2017 Philip J. Freeman <elektron@halo.nu> */
+
+static void stars(fb_fragment_t *fragment)
+{
+	static int	initialized, z;
+	static struct	universe* u;
+
+	struct		return_point rp;
+	int		x, y, width = fragment->width, height = fragment->height;
+
+	if (!initialized) {
+		z = 128;
+		srand(time(NULL) + getpid());
+
+		// Initialize the stars lib (and pre-add a bunch of stars)
+		new_universe(&u, width, height, z);
+		for(y=0; y<z; y++) {
+			while (process_point(u, &rp) != 0);
+			for(x=0; x<rand()%128; x++){
+				new_point(u);
+			}
+		}
+		initialized = 1;
+	}
+
+	// draw space (or blank the frame, if you prefer)
+	memset(fragment->buf, 0, ((fragment->width << 2) + fragment->stride) * fragment->height);
+
+	// draw stars
+	for (;;) {
+		int ret = process_point( u, &rp  );
+		if (ret==0) break;
+		if (ret==1) draw_pixel(fragment, rp.x+(width/2), rp.y+(height/2),
+				       makergb(0xFF, 0xFF, 0xFF, (float)rp.opacity/OPACITY_MAX)
+				      );
+	}
+
+	// add stars at horizon
+	for (x=0; x<rand()%128; x++) {
+		new_point(u);
+	}
+}
+
+rototiller_renderer_t	stars_renderer = {
+	.render = stars,
+	.name = "stars",
+	.description = "basic starfield",
+	.author = "Philip J Freeman <elektron@halo.nu>",
+	.license = "GPLv2",
+};