svn commit: r293034 - in head: share/man/man4 sys/dev/syscons/plasma sys/modules/syscons sys/modules/syscons/plasma
Dag-Erling Smørgrav
des at FreeBSD.org
Fri Jan 1 04:04:42 UTC 2016
Author: des
Date: Fri Jan 1 04:04:40 2016
New Revision: 293034
URL: https://svnweb.freebsd.org/changeset/base/293034
Log:
17 years and change after I wrote warp_saver, here's a simple plasma effect
(currently only three circular patterns) which requires quite a bit of
fixed-point arithmetic, including sqrt() and cos(). Happy New Year!
Added:
head/sys/dev/syscons/plasma/
head/sys/dev/syscons/plasma/fp16.c (contents, props changed)
head/sys/dev/syscons/plasma/fp16.h (contents, props changed)
head/sys/dev/syscons/plasma/plasma_saver.c (contents, props changed)
head/sys/modules/syscons/plasma/
head/sys/modules/syscons/plasma/Makefile (contents, props changed)
Modified:
head/share/man/man4/splash.4
head/sys/modules/syscons/Makefile
Modified: head/share/man/man4/splash.4
==============================================================================
--- head/share/man/man4/splash.4 Fri Jan 1 03:59:09 2016 (r293033)
+++ head/share/man/man4/splash.4 Fri Jan 1 04:04:40 2016 (r293034)
@@ -26,7 +26,7 @@
.\"
.\" $FreeBSD$
.\"
-.Dd November 29, 2010
+.Dd December 31, 2015
.Dt SPLASH 4
.Os
.Sh NAME
@@ -130,6 +130,8 @@ the screen will also be powered off.
Animated graphical
.Fx
logo.
+.It Pa plasma_saver.ko
+Draws an animated interference pattern.
.It Pa rain_saver.ko
Draws a shower on the screen.
.It Pa snake_saver.ko
@@ -282,6 +284,14 @@ based on the
code, with some additional inspiration from the
.Pa daemon_saver
code.
+The
+.Pa logo_saver ,
+.Pa plasma_saver ,
+.Pa rain_saver
+and
+.Pa warp_saver
+modules were written by
+.An Dag-Erling Sm\(/orgrav Aq Mt des at FreeBSD.org .
.Sh CAVEATS
Both the splash screen and the screen saver work with
.Xr syscons 4
Added: head/sys/dev/syscons/plasma/fp16.c
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ head/sys/dev/syscons/plasma/fp16.c Fri Jan 1 04:04:40 2016 (r293034)
@@ -0,0 +1,131 @@
+/*-
+ * Copyright (c) 2015 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifdef _KERNEL
+#include <sys/libkern.h>
+#else
+#include <stdio.h>
+#include <strings.h>
+#endif
+
+#include "fp16.h"
+
+/*
+ * Compute the quare root of x, using Newton's method with 2^(log2(x)/2)
+ * as the initial estimate.
+ */
+fp16_t
+fp16_sqrt(fp16_t x)
+{
+ fp16_t y, delta;
+ signed int log2x;
+
+ /* special case */
+ if (x == 0)
+ return (0);
+
+ /* shift toward 0 by half the logarithm */
+ log2x = flsl(x) - 1;
+ if (log2x >= 16) {
+ y = x >> (log2x - 16) / 2;
+ } else {
+#if 0
+ y = x << (16 - log2x) / 2;
+#else
+ /* XXX for now, return 0 for anything < 1 */
+ return (0);
+#endif
+ }
+ while (y > 0) {
+ /* delta = y^2 / 2y */
+ delta = fp16_div(fp16_sub(fp16_mul(y, y), x), y * 2);
+ if (delta == 0)
+ break;
+ y = fp16_sub(y, delta);
+ }
+ return (y);
+}
+
+static fp16_t fp16_cos_table[256] = {
+ 65536, 65534, 65531, 65524, 65516, 65505, 65491, 65475,
+ 65457, 65436, 65412, 65386, 65358, 65327, 65294, 65258,
+ 65220, 65179, 65136, 65091, 65043, 64992, 64939, 64884,
+ 64826, 64766, 64703, 64638, 64571, 64501, 64428, 64353,
+ 64276, 64197, 64115, 64030, 63943, 63854, 63762, 63668,
+ 63571, 63473, 63371, 63268, 63162, 63053, 62942, 62829,
+ 62714, 62596, 62475, 62353, 62228, 62100, 61971, 61839,
+ 61705, 61568, 61429, 61288, 61144, 60998, 60850, 60700,
+ 60547, 60392, 60235, 60075, 59913, 59749, 59583, 59414,
+ 59243, 59070, 58895, 58718, 58538, 58356, 58172, 57986,
+ 57797, 57606, 57414, 57219, 57022, 56822, 56621, 56417,
+ 56212, 56004, 55794, 55582, 55368, 55152, 54933, 54713,
+ 54491, 54266, 54040, 53811, 53581, 53348, 53114, 52877,
+ 52639, 52398, 52155, 51911, 51665, 51416, 51166, 50914,
+ 50660, 50403, 50146, 49886, 49624, 49360, 49095, 48828,
+ 48558, 48288, 48015, 47740, 47464, 47186, 46906, 46624,
+ 46340, 46055, 45768, 45480, 45189, 44897, 44603, 44308,
+ 44011, 43712, 43412, 43110, 42806, 42501, 42194, 41885,
+ 41575, 41263, 40950, 40636, 40319, 40002, 39682, 39362,
+ 39039, 38716, 38390, 38064, 37736, 37406, 37075, 36743,
+ 36409, 36074, 35738, 35400, 35061, 34721, 34379, 34036,
+ 33692, 33346, 32999, 32651, 32302, 31952, 31600, 31247,
+ 30893, 30538, 30181, 29824, 29465, 29105, 28745, 28383,
+ 28020, 27656, 27291, 26925, 26557, 26189, 25820, 25450,
+ 25079, 24707, 24334, 23960, 23586, 23210, 22833, 22456,
+ 22078, 21699, 21319, 20938, 20557, 20175, 19792, 19408,
+ 19024, 18638, 18253, 17866, 17479, 17091, 16702, 16313,
+ 15923, 15533, 15142, 14751, 14359, 13966, 13573, 13179,
+ 12785, 12390, 11995, 11600, 11204, 10807, 10410, 10013,
+ 9616, 9218, 8819, 8421, 8022, 7623, 7223, 6823,
+ 6423, 6023, 5622, 5222, 4821, 4420, 4018, 3617,
+ 3215, 2814, 2412, 2010, 1608, 1206, 804, 402,
+};
+
+/*
+ * Compute the cosine of theta.
+ */
+fp16_t
+fp16_cos(fp16_t theta)
+{
+ unsigned int i;
+
+ i = 1024 * (theta % FP16_2PI) / FP16_2PI;
+ switch (i / 256) {
+ case 0:
+ return (fp16_cos_table[i % 256]);
+ case 1:
+ return (-fp16_cos_table[255 - i % 256]);
+ case 2:
+ return (-fp16_cos_table[i % 256]);
+ case 3:
+ return (fp16_cos_table[255 - i % 256]);
+ default:
+ /* inconceivable! */
+ return (0);
+ }
+}
Added: head/sys/dev/syscons/plasma/fp16.h
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ head/sys/dev/syscons/plasma/fp16.h Fri Jan 1 04:04:40 2016 (r293034)
@@ -0,0 +1,84 @@
+/*-
+ * Copyright (c) 2015 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef FP16_H_INCLUDED
+#define FP16_H_INCLUDED
+
+typedef signed long long fp16_t;
+
+#define ItoFP16(n) ((signed long long)(n) << 16)
+#define FP16toI(n) ((signed long long)(n) >> 16)
+
+#ifndef _KERNEL
+#define FP16toF(n) ((n) / 65536.0)
+#endif
+
+/* add a and b */
+static inline fp16_t
+fp16_add(fp16_t a, fp16_t b)
+{
+
+ return (a + b);
+}
+
+/* subtract b from a */
+static inline fp16_t
+fp16_sub(fp16_t a, fp16_t b)
+{
+
+ return (a - b);
+}
+
+/* multiply a by b */
+static inline fp16_t
+fp16_mul(fp16_t a, fp16_t b)
+{
+
+ return (a * b >> 16);
+}
+
+/* divide a by b */
+static inline fp16_t
+fp16_div(fp16_t a, fp16_t b)
+{
+
+ return ((a << 16) / b);
+}
+
+/* square root */
+fp16_t fp16_sqrt(fp16_t);
+
+#define FP16_2PI 411774
+#define FP16_PI 205887
+#define FP16_PI_2 102943
+#define FP16_PI_4 51471
+
+/* cosine */
+fp16_t fp16_cos(fp16_t);
+
+#endif
Added: head/sys/dev/syscons/plasma/plasma_saver.c
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ head/sys/dev/syscons/plasma/plasma_saver.c Fri Jan 1 04:04:40 2016 (r293034)
@@ -0,0 +1,239 @@
+/*-
+ * Copyright (c) 2015 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ *
+ * To CJA, in appreciation of Nighthawk brunches past and future.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
+#include <sys/syslog.h>
+#include <sys/consio.h>
+#include <sys/fbio.h>
+
+#include <dev/fb/fbreg.h>
+#include <dev/fb/splashreg.h>
+#include <dev/syscons/syscons.h>
+
+#define SAVER_NAME "plasma_saver"
+
+#include "fp16.h"
+
+/*
+ * Preferred video modes
+ */
+static int modes[] = {
+ M_VGA_CG640,
+ M_PC98_PEGC640x480,
+ M_PC98_PEGC640x400,
+ M_VGA_CG320,
+ -1
+};
+
+/*
+ * Display parameters
+ */
+static unsigned char *vid;
+static unsigned int banksize, scrmode, scrw, scrh;
+static unsigned int blanked;
+
+/*
+ * List of foci
+ */
+#define FOCI 3
+static struct {
+ int x, y; /* coordinates */
+ int vx, vy; /* velocity */
+} plasma_foci[FOCI];
+
+/*
+ * Palette
+ */
+static struct {
+ unsigned char r, g, b;
+} plasma_pal[256];
+
+/*
+ * Draw a new frame
+ */
+static void
+plasma_update(video_adapter_t *adp)
+{
+ unsigned int x, y; /* coordinates */
+ signed int dx, dy; /* horizontal / vertical distance */
+ fp16_t sqd, d; /* square of distance and distance */
+ fp16_t m; /* magnitude */
+ unsigned int org, off; /* origin and offset */
+ unsigned int i; /* loop index */
+
+ /* switch to bank 0 */
+ vidd_set_win_org(adp, 0);
+ /* for each scan line */
+ for (y = org = off = 0; y < scrh; ++y) {
+ /* for each pixel on scan line */
+ for (x = 0; x < scrw; ++x, ++off) {
+ /* for each focus */
+ for (i = m = 0; i < FOCI; ++i) {
+ dx = x - plasma_foci[i].x;
+ dy = y - plasma_foci[i].y;
+ sqd = ItoFP16(dx * dx + dy * dy);
+ d = fp16_sqrt(sqd);
+ /* divide by 4 to stretch out the pattern */
+ m = fp16_add(m, fp16_cos(d / 4));
+ }
+ /*
+ * m is now in the range +/- FOCI, but we need a
+ * value between 0 and 255. We scale to +/- 127
+ * and add 127, which moves it into the range [0,
+ * 254].
+ */
+ m = fp16_mul(m, ItoFP16(127));
+ m = fp16_div(m, ItoFP16(FOCI));
+ m = fp16_add(m, ItoFP16(127));
+ /* switch banks if necessary */
+ if (off > banksize) {
+ off -= banksize;
+ org += banksize;
+ vidd_set_win_org(adp, org);
+ }
+ /* plot */
+ vid[off] = FP16toI(m);
+ }
+ }
+ /* now move the foci */
+ for (i = 0; i < FOCI; ++i) {
+ plasma_foci[i].x += plasma_foci[i].vx;
+ if (plasma_foci[i].x < 0) {
+ /* bounce against left wall */
+ plasma_foci[i].vx = -plasma_foci[i].vx;
+ plasma_foci[i].x = -plasma_foci[i].x;
+ } else if (plasma_foci[i].x >= scrw) {
+ /* bounce against right wall */
+ plasma_foci[i].vx = -plasma_foci[i].vx;
+ plasma_foci[i].x = scrw - (plasma_foci[i].x - scrw);
+ }
+ plasma_foci[i].y += plasma_foci[i].vy;
+ if (plasma_foci[i].y < 0) {
+ /* bounce against ceiling */
+ plasma_foci[i].vy = -plasma_foci[i].vy;
+ plasma_foci[i].y = -plasma_foci[i].y;
+ } else if (plasma_foci[i].y >= scrh) {
+ /* bounce against floor */
+ plasma_foci[i].vy = -plasma_foci[i].vy;
+ plasma_foci[i].y = scrh - (plasma_foci[i].y - scrh);
+ }
+ }
+}
+
+/*
+ * Start or stop the screensaver
+ */
+static int
+plasma_saver(video_adapter_t *adp, int blank)
+{
+ int pl;
+
+ if (blank) {
+ /* switch to graphics mode */
+ if (blanked <= 0) {
+ pl = splhigh();
+ vidd_set_mode(adp, scrmode);
+ vidd_load_palette(adp, (unsigned char *)plasma_pal);
+ vidd_set_border(adp, 0);
+ blanked++;
+ vid = (unsigned char *)adp->va_window;
+ banksize = adp->va_window_size;
+ splx(pl);
+ vidd_clear(adp);
+ }
+ /* update display */
+ plasma_update(adp);
+ } else {
+ blanked = 0;
+ }
+ return (0);
+}
+
+/*
+ * Initialize on module load
+ */
+static int
+plasma_init(video_adapter_t *adp)
+{
+ video_info_t info;
+ int i;
+
+ /* select video mode */
+ for (i = 0; modes[i] >= 0; ++i)
+ if (vidd_get_info(adp, modes[i], &info) == 0)
+ break;
+ if (modes[i] < 0) {
+ log(LOG_NOTICE, "%s: no supported video modes\n", SAVER_NAME);
+ return (ENODEV);
+ }
+ scrmode = modes[i];
+ scrw = info.vi_width;
+ scrh = info.vi_height;
+
+ /* initialize the palette */
+ for (i = 0; i < 256; ++i)
+ plasma_pal[i].r = plasma_pal[i].g = plasma_pal[i].b = i;
+
+ /* randomize the foci */
+ for (i = 0; i < FOCI; i++) {
+ plasma_foci[i].x = random() % scrw;
+ plasma_foci[i].y = random() % scrh;
+ plasma_foci[i].vx = random() % 5 - 2;
+ plasma_foci[i].vy = random() % 5 - 2;
+ }
+
+ return (0);
+}
+
+/*
+ * Clean up before module unload
+ */
+static int
+plasma_term(video_adapter_t *adp)
+{
+
+ return (0);
+}
+
+/*
+ * Boilerplate
+ */
+static scrn_saver_t plasma_module = {
+ SAVER_NAME,
+ plasma_init,
+ plasma_term,
+ plasma_saver,
+ NULL
+};
+
+SAVER_MODULE(plasma_saver, plasma_module);
Modified: head/sys/modules/syscons/Makefile
==============================================================================
--- head/sys/modules/syscons/Makefile Fri Jan 1 03:59:09 2016 (r293033)
+++ head/sys/modules/syscons/Makefile Fri Jan 1 04:04:40 2016 (r293034)
@@ -9,6 +9,7 @@ SUBDIR= ${_apm} \
${_fire} \
green \
${_logo} \
+ ${_plasma} \
${_rain} \
${_snake} \
${_star} \
@@ -25,6 +26,7 @@ _daemon= daemon
_dragon= dragon
_fire= fire
_logo= logo
+_plasma= plasma
_rain= rain
_snake= snake
_star= star
Added: head/sys/modules/syscons/plasma/Makefile
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ head/sys/modules/syscons/plasma/Makefile Fri Jan 1 04:04:40 2016 (r293034)
@@ -0,0 +1,8 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../../dev/syscons/plasma
+
+KMOD= plasma_saver
+SRCS= fp16.c plasma_saver.c
+
+.include <bsd.kmod.mk>
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