modules/blinds: add simple 80s-aesthetic window blinds

This isn't super interesting but I might just start adding
simplistic overlay style modules for compositing/transition use.

3 files changed, 49 insertions, 1 deletions

diff --git a/src/modules/Makefile.am b/src/modules/Makefile.am
index 28fc7fd..c791bc9 100644
--- a/src/modules/Makefile.am
+++ b/src/modules/Makefile.am
@@ -1 +1 @@
-SUBDIRS = compose drizzle flui2d julia meta2d montage pixbounce plasma plato ray roto rtv snow sparkler spiro stars submit swab swarm
+SUBDIRS = blinds compose drizzle flui2d julia meta2d montage pixbounce plasma plato ray roto rtv snow sparkler spiro stars submit swab swarm
diff --git a/src/modules/blinds/Makefile.am b/src/modules/blinds/Makefile.am
new file mode 100644
index 0000000..c1c1bfa
--- /dev/null
+++ b/src/modules/blinds/Makefile.am
@@ -0,0 +1,3 @@
+noinst_LTLIBRARIES = libblinds.la
+libblinds_la_SOURCES = blinds.c
+libblinds_la_CPPFLAGS = -I@top_srcdir@/src -I@top_srcdir@/src/libs
diff --git a/src/modules/blinds/blinds.c b/src/modules/blinds/blinds.c
new file mode 100644
index 0000000..080b468
--- /dev/null
+++ b/src/modules/blinds/blinds.c
@@ -0,0 +1,45 @@
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "til.h"
+#include "til_fb.h"
+
+/* Copyright (C) 2017-2022 Vito Caputo <vcaputo@pengaru.com> */
+
+#define	NUM_BLINDS	16
+
+/* draw a blind over fragment */
+static inline void draw_blind(til_fb_fragment_t *fragment, unsigned row, float t)
+{
+	unsigned	row_height = fragment->frame_height / NUM_BLINDS;
+	unsigned	height = roundf(t * (float)row_height);
+
+	for (unsigned y = 0; y < height; y++)
+		memset(fragment->buf + ((row * row_height) + y ) * (fragment->pitch >> 2), 0xff, fragment->width * 4);
+}
+
+
+/* draw blinds over the fragment */
+static void blinds_render_fragment(void *context, unsigned ticks, unsigned cpu, til_fb_fragment_t *fragment)
+{
+	static float rr;
+
+	unsigned	row;
+	float		r;
+
+	til_fb_fragment_clear(fragment);
+
+	for (r = rr, row = 0; row < NUM_BLINDS; row++, r += .1)
+		draw_blind(fragment, row, 1.f - fabsf(cosf(r)));
+
+	rr += .01;
+}
+
+
+til_module_t	blinds_module = {
+	.render_fragment = blinds_render_fragment,
+	.name = "blinds",
+	.description = "Retro 80s-inspired window blinds",
+	.author = "Vito Caputo <vcaputo@pengaru.com>",
+};