sparkler: enable rudimentary threaded rendering

This moves most of the particle system maintenance into the serially
executed sparkler_prepare_frame(), divides the frame into ncpus
fragments, and leaves the draw to occur concurrently.

The drawing must still currently process all particles and simply skips
drawing those falling outside the fragment.

Moving more of the computation out of prepare_frame() and into
render_fragment() is left for future improvements, as it's a bit
complex to do gainfully.

1 files changed, 15 insertions, 7 deletions

diff --git a/src/modules/sparkler/sparkler.c b/src/modules/sparkler/sparkler.c
index 6d8d354..a2210dc 100644
--- a/src/modules/sparkler/sparkler.c
+++ b/src/modules/sparkler/sparkler.c
@@ -58,28 +58,36 @@ static void sparkler_destroy_context(void *context)
 }
 
 
+static void sparkler_prepare_frame(void *context, unsigned ncpus, fb_fragment_t *fragment, rototiller_frame_t *res_frame)
+{
+	sparkler_context_t	*ctxt = context;
+
+	fb_fragment_divide(fragment, ncpus, res_frame->fragments);
+	res_frame->n_fragments = ncpus;
+
+	particles_sim(ctxt->particles);
+	particles_add_particles(ctxt->particles, NULL, &simple_ops, INIT_PARTS / 4);
+	particles_age(ctxt->particles);
+}
+
+
 /* Render a 3D particle system */
 static void sparkler_render_fragment(void *context, fb_fragment_t *fragment)
 {
 	sparkler_context_t	*ctxt = context;
-	uint32_t		*buf = fragment->buf;
-
 
 	fb_fragment_zero(fragment);
-
-	particles_age(ctxt->particles);
 	particles_draw(ctxt->particles, fragment);
-	particles_sim(ctxt->particles);
-	particles_add_particles(ctxt->particles, NULL, &simple_ops, INIT_PARTS / 4);
 }
 
 
 rototiller_module_t	sparkler_module = {
 	.create_context = sparkler_create_context,
 	.destroy_context = sparkler_destroy_context,
+	.prepare_frame = sparkler_prepare_frame,
 	.render_fragment = sparkler_render_fragment,
 	.name = "sparkler",
-	.description = "Particle system with spatial interactions",
+	.description = "Particle system with spatial interactions (threaded (poorly))",
 	.author = "Vito Caputo <vcaputo@pengaru.com>",
 	.license = "GPLv2",
 };