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foxbox/firmware/drivers/lcd-scroll.c
William Wilgus fffae07833 [Bugfix] Scroll engine, backwards scrolling causes display corruption
When a line is over a selected length bi-directional scrolling
is disabled.

In non bidir scrolling the string is copied to a buffer twice with
a space between "scroll text" + "   " + "scroll text"

this is to allow scrolling the line in the forward direction
with minimal extra logic

Note: that is the ONLY direction it is equiped to handle

In the USB screen I observed while switching through the different modes
that sometimes the text was corrupted

turns out you can still have scroll->backwards set to true
which causes offset to go negatve but we never check if offset < 0
in non bidir scrolling mode and happily continue with ever more negative offsets

Change-Id: I210f7880be953d3cc42469828a7ca5fc2b2ab96f
2025-03-09 09:16:07 -04:00

239 lines
7.3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2007 by Michael Sevakis
*
* LCD scroll control functions (API to apps).
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
/* This file is meant to be #included by scroll_engine.c (twice if a remote
* is present) */
#ifndef LCDFN /* Not compiling for remote - define macros for main LCD. */
#define LCDFN(fn) lcd_ ## fn
#define LCDM(ma) LCD_ ## ma
#define MAIN_LCD
#endif
#if !defined(BOOTLOADER)
static struct scrollinfo LCDFN(scroll)[LCDM(SCROLLABLE_LINES)];
struct scroll_screen_info LCDFN(scroll_info) =
{
.scroll = LCDFN(scroll),
.lines = 0,
.ticks = 12,
.delay = HZ/2,
.bidir_limit = 50,
.step = 6,
};
void LCDFN(scroll_stop)(void)
{
for (int i = 0; i < LCDFN(scroll_info).lines; i++)
{
/* inform scroller about end of scrolling */
struct scrollinfo *s = &LCDFN(scroll_info).scroll[i];
s->line = NULL;
s->scroll_func(s);
}
LCDFN(scroll_info).lines = 0;
}
/* Clears scrolling lines that intersect with the area */
void LCDFN(scroll_stop_viewport_rect)(const struct viewport *vp, int x, int y, int width, int height)
{
int i = 0;
while (i < LCDFN(scroll_info).lines)
{
struct scrollinfo *s = &LCDFN(scroll_info).scroll[i];
/* check if the specified area crosses the viewport in some way */
if (s->vp == vp
&& (x < (s->x+s->width) && (x+width) > s->x)
&& (y < (s->y+s->height) && (y+height) > s->y))
{
/* inform scroller about end of scrolling */
s->line = NULL;
s->scroll_func(s);
/* If i is not the last active line in the array, then move
the last item to position i. This compacts
the scroll array at the same time of removing the line */
if ((i + 1) != LCDFN(scroll_info).lines)
{
LCDFN(scroll_info).scroll[i] =
LCDFN(scroll_info).scroll[LCDFN(scroll_info).lines-1];
}
LCDFN(scroll_info).lines--;
}
else
{
i++;
}
}
}
/* Stop all scrolling lines in the specified viewport */
void LCDFN(scroll_stop_viewport)(const struct viewport *vp)
{
LCDFN(scroll_stop_viewport_rect)(vp, 0, 0, vp->width, vp->height);
}
void LCDFN(scroll_speed)(int speed)
{
LCDFN(scroll_info).ticks = scroll_tick_table[speed];
}
void LCDFN(scroll_step)(int step)
{
LCDFN(scroll_info).step = step;
}
void LCDFN(scroll_delay)(int ms)
{
LCDFN(scroll_info).delay = ms / (HZ / 10);
}
void LCDFN(bidir_scroll)(int percent)
{
LCDFN(scroll_info).bidir_limit = percent;
}
/* This renders the scrolling line described by s immediatly.
* This can be called to update a scrolling line if the text has changed
* without waiting for the next scroll tick
*
* Returns true if the text scrolled to the end */
bool LCDFN(scroll_now)(struct scrollinfo *s)
{
int width = s->line_stringsize; /* Calculated by LCDFN puts_scroll_worker() */
/*int width = font_getstringsize(s->linebuffer, NULL, NULL, s->vp->font);*/
bool ended = false;
/* assume s->scroll_func() don't yield; otherwise this buffer might need
* to be mutex'd (the worst case would be minor glitches though) */
static char line_buf[SCROLL_LINE_SIZE];
if (s->bidir)
{ /* scroll bidirectional */
s->line = s->linebuffer;
if (s->offset <= 0) {
/* at beginning of line */
s->offset = 0;
s->backward = false;
ended = true;
}
else if (s->offset >= width - s->width) {
/* at end of line */
s->offset = width - s->width;
s->backward = true;
ended = true;
}
}
else
{
s->backward = false; /* bugfix we only account for forward scrolling here */
snprintf(line_buf, sizeof(line_buf)-1, "%s%s%s",
s->linebuffer, " ", s->linebuffer);
s->line = line_buf;
width += font_getstringsize(" ", NULL, NULL, s->vp->font) * 3;
/* scroll forward the whole time */
if (s->offset >= width) {
s->offset = 0;
ended = true;
}
}
/* Stash and restore these four, so that the scroll_func
* can do whatever it likes without destroying the state */
struct frame_buffer_t *framebuf = s->vp->buffer;
unsigned drawmode;
#if LCD_DEPTH > 1
unsigned fg_pattern, bg_pattern;
fg_pattern = s->vp->fg_pattern;
bg_pattern = s->vp->bg_pattern;
#endif
drawmode = s->vp->drawmode;
s->scroll_func(s);
LCDFN(update_viewport_rect)(s->x, s->y, s->width, s->height);
#if LCD_DEPTH > 1
s->vp->fg_pattern = fg_pattern;
s->vp->bg_pattern = bg_pattern;
#endif
s->vp->drawmode = drawmode;
s->vp->buffer = framebuf;
return ended;
}
static void LCDFN(scroll_worker)(void)
{
int index;
struct scroll_screen_info *si = &LCDFN(scroll_info);
struct viewport *oldvp;
if (global_settings.disable_mainmenu_scrolling
&& get_current_activity() == ACTIVITY_MAINMENU) {
/* No scrolling on the main menu if disabled
(to not break themes with lockscreens) */
return;
}
for ( index = 0; index < si->lines; index++ )
{
struct scrollinfo *s = &si->scroll[index];
/* check pause */
if (TIME_BEFORE(current_tick, s->start_tick)) {
continue;
}
s->start_tick = current_tick;
if (s->backward)
s->offset -= si->step;
else
s->offset += si->step;
/* this runs out of the ui thread, thus we need to
* save and restore the current viewport since the
* ui thread is unaware of the swapped viewports. */
oldvp = LCDFN(set_viewport_ex)(s->vp, 0); /* don't mark the last vp as dirty */
/* put the line onto the display now */
bool makedelay = LCDFN(scroll_now(s));
if (makedelay)
{
#if 0 /* haven't found a case in which this matters .. yet?? --Bilgus */
/* re-calculate stringsize in case the font changed */
s->line_stringsize = font_getstringsize(s->linebuffer, NULL, NULL, s->vp->font);
#endif
s->start_tick += si->delay + si->ticks;
}
#ifdef SIMULATOR /* Bugfix sim won't update screen unless called from active thread */
LCDFN(set_viewport)(oldvp);
#else
LCDFN(set_viewport_ex)(oldvp, 0); /* don't mark the last vp as dirty */
#endif
}
}
#endif /*!BOOTLOADER*/